Fang-Fang Yin

Journal article Med Phys · January 2026 BACKGROUND: Medical image analysis has witnessed substantial advancements through recent deep learning (DL) algorithms development. Vision Transformers (ViTs) have emerged as a powerful alternative solution by leveraging self-attention to model both local ... Full text Link to item Cite

Generation, validation, and benchmarking of a commercial independent Monte Carlo calculation beam model for multi-target SRS.

Journal article Z Med Phys · August 2025 BACKGROUND: Dosimetric validation of single isocenter multi-target radiosurgery plans is difficult due to conditions of electronic disequilibrium and the simultaneous irradiation of multiple off-axis lesions dispersed throughout the volume. Here we report ... Full text Link to item Cite

Understanding of FLASH radiotherapy through physical to biological interpretation

Journal article Radiation Medicine and Protection · August 1, 2025 This study presents a unified framework, systematically shows a detailed visual representation and emphasizes the understanding via various key factors throughout physical-chemical-biological stages underlying the irradiation process in FLASH radiotherapy ... Full text Cite

Finite Element Method-Based Hybrid MRI/CBCT Generation to Improve Liver Stereotactic Body Radiation Therapy Targets Localization Accuracy.

Journal article IEEE Trans Radiat Plasma Med Sci · March 2025 Cone-beam CT (CBCT) is commonly used in treatment imaging, but its limited soft tissue contrast presents challenges for liver tumor localization. As a result, indirect localization methods relying on the liver's boundary are commonly utilized, which have l ... Full text Link to item Cite

A neural ordinary differential equation model for visualizing deep neural network behaviors in multi-parametric MRI-based glioma segmentation.

Journal article Med Phys · August 2023 PURPOSE: To develop a neural ordinary differential equation (ODE) model for visualizing deep neural network behavior during multi-parametric MRI-based glioma segmentation as a method to enhance deep learning explainability. METHODS: By hypothesizing that d ... Full text Link to item Cite

Stereotactic Radiosurgery vs Conventional Radiotherapy for Localized Vertebral Metastases of the Spine: Phase 3 Results of NRG Oncology/RTOG 0631 Randomized Clinical Trial.

Journal article JAMA Oncol · June 1, 2023 IMPORTANCE: Spine metastasis can be treated with high-dose radiation therapy with advanced delivery technology for long-term tumor and pain control. OBJECTIVE: To assess whether patient-reported pain relief was improved with stereotactic radiosurgery (SRS) ... Full text Link to item Cite

Uncertainties in the dosimetric heterogeneity correction and its potential effect on local control in lung SBRT.

Journal article Biomed Phys Eng Express · March 7, 2023 Objective. Dose calculation in lung stereotactic body radiation therapy (SBRT) is challenging due to the low density of the lungs and small volumes. Here we assess uncertainties associated with tissue heterogeneities using different dose calculation algori ... Full text Link to item Cite

View-sharing for 4D magnetic resonance imaging with randomized projection-encoding enables improvements of respiratory motion imaging for treatment planning in abdominothoracic radiotherapy.

Journal article Phys Imaging Radiat Oncol · January 2023 BACKGROUND AND PURPOSE: The accuracy and precision of radiation therapy are dependent on the characterization of organ-at-risk and target motion. This work aims to demonstrate a 4D magnetic resonance imaging (MRI) method for improving spatial and temporal ... Full text Link to item Cite

Quantification of lung function on CT images based on pulmonary radiomic filtering.

Journal article Med Phys · November 2022 PURPOSE: To develop a radiomics filtering technique for characterizing spatial-encoded regional pulmonary ventilation information on lung computed tomography (CT). METHODS: The lung volume was segmented on 46 CT images, and a 3D sliding window kernel was i ... Full text Link to item Cite

Input feature design and its impact on the performance of deep learning models for predicting fluence maps in intensity-modulated radiation therapy.

Journal article Phys Med Biol · October 21, 2022 Objective. Deep learning (DL) models for fluence map prediction (FMP) have great potential to reduce treatment planning time in intensity-modulated radiation therapy (IMRT) by avoiding the lengthy inverse optimization process. This study aims to improve th ... Full text Link to item Cite

Fast four-dimensional cone-beam computed tomography reconstruction using deformable convolutional networks.

Journal article Med Phys · October 2022 BACKGROUND: Although four-dimensional cone-beam computed tomography (4D-CBCT) is valuable to provide onboard image guidance for radiotherapy of moving targets, it requires a long acquisition time to achieve sufficient image quality for target localization. ... Full text Link to item Cite

Radiomics: a primer on high-throughput image phenotyping.

Journal article Abdom Radiol (NY) · September 2022 Radiomics is a high-throughput approach to image phenotyping. It uses computer algorithms to extract and analyze a large number of quantitative features from radiological images. These radiomic features collectively describe unique patterns that can serve ... Full text Link to item Cite

Improving liver tumor image contrast and synthesizing novel tissue contrasts by adaptive multiparametric MRI fusion.

Journal article Precis Radiat Oncol · September 2022 PURPOSE: Multiparametric MRI contains rich and complementary anatomical and functional information, which is often utilized separately. This study aims to propose an adaptive multiparametric MRI (mpMRI) fusion method and examine its capability in improving ... Full text Link to item Cite

Impact of image quality on radiomics applications.

Journal article Phys Med Biol · July 22, 2022 Radiomics features extracted from medical images have been widely reported to be useful in the patient specific outcome modeling for variety of assessment and prediction purposes. Successful application of radiomics features as imaging biomarkers, however, ... Full text Link to item Cite

Patient-specific synthetic magnetic resonance imaging generation from cone beam computed tomography for image guidance in liver stereotactic body radiation therapy.

Journal article Precis Radiat Oncol · June 2022 OBJECTIVE: Despite its prevalence, cone beam computed tomography (CBCT) has poor soft-tissue contrast, making it challenging to localize liver tumors. We propose a patient-specific deep learning model to generate synthetic magnetic resonance imaging (MRI) ... Full text Link to item Cite

A geometry-guided multi-beamlet deep learning technique for CT reconstruction.

Journal article Biomed Phys Eng Express · May 13, 2022 Purpose. Previous studies have proposed deep-learning techniques to reconstruct CT images from sinograms. However, these techniques employ large fully-connected (FC) layers for projection-to-image domain transformation, producing large models requiring sub ... Full text Link to item Cite

Patient-specific deep learning model to enhance 4D-CBCT image for radiomics analysis.

Journal article Phys Med Biol · April 1, 2022 Objective.4D-CBCT provides phase-resolved images valuable for radiomics analysis for outcome prediction throughout treatment courses. However, 4D-CBCT suffers from streak artifacts caused by under-sampling, which severely degrades the accuracy of radiomic ... Full text Link to item Cite

Enhancement of 4-D Cone-Beam Computed Tomography (4D-CBCT) Using a Dual-Encoder Convolutional Neural Network (DeCNN).

Journal article IEEE Trans Radiat Plasma Med Sci · February 2022 4D-CBCT is a powerful tool to provide respiration-resolved images for the moving target localization. However, projections in each respiratory phase are intrinsically under-sampled under the clinical scanning time and imaging dose constraints. Images recon ... Full text Link to item Cite

The Effect of Various Dose Normalization Strategies When Implementing Linear Boltzmann Transport Equation Dose Calculation for Lung Stereotactic Body Radiation Therapy Planning.

Journal article Pract Radiat Oncol · 2022 PURPOSE: To explore implications of various plan normalizations when implementing a linear Boltzmann transport equation solver dose calculation algorithm (LBTE) for lung stereotactic body radiation therapy (SBRT). METHODS AND MATERIALS: Eighty-seven plans ... Full text Link to item Cite

Evaluation of two automated treatment planning techniques for multiple brain metastases using a single isocenter.

Journal article J Radiosurg SBRT · 2022 Two automated treatment planning techniques were evaluated for multiple brain metastases using a single isocenter. One technique is knowledge-based planning (KBP) using a stereotactic radiosurgery (SRS) model in Eclipse treatment planning system (TPS); and ... Link to item Cite

Post-Radiotherapy PET Image Outcome Prediction by Deep Learning Under Biological Model Guidance: A Feasibility Study of Oropharyngeal Cancer Application.

Journal article Front Oncol · 2022 PURPOSE: To develop a method of biologically guided deep learning for post-radiation 18FDG-PET image outcome prediction based on pre-radiation images and radiotherapy dose information. METHODS: Based on the classic reaction-diffusion mechanism, a novel bio ... Full text Link to item Cite

Dosimetric variation in preoperative partial breast radiosurgery assessed by deformable image registrations.

Journal article J Radiosurg SBRT · 2022 OBJECTIVE: To assess dosimetric variation caused by breast deformation in breast radiosurgery based on deformable image registration. METHODS: This study included 30 patients who were treated in the prone position for preoperative partial breast radiosurge ... Link to item Cite

Prior image-guided cone-beam computed tomography augmentation from under-sampled projections using a convolutional neural network.

Journal article Quant Imaging Med Surg · December 2021 BACKGROUND: Acquiring sparse-view cone-beam computed tomography (CBCT) is an effective way to reduce the imaging dose. However, images reconstructed by the conventional filtered back-projection method suffer from severe streak artifacts due to the projecti ... Full text Link to item Cite

Artificial intelligence applications in intensity modulated radiation treatment planning: an overview.

Journal article Quant Imaging Med Surg · December 2021 Artificial intelligence (AI) refers to methods that improve and automate challenging human tasks by systematically capturing and applying relevant knowledge in these tasks. Over the past decades, a number of approaches have been developed to address differ ... Full text Link to item Cite

Multi-contrast four-dimensional magnetic resonance imaging (MC-4D-MRI): Development and initial evaluation in liver tumor patients.

Journal article Med Phys · December 2021 PURPOSE: To develop a novel multi-contrast four-dimensional magnetic resonance imaging (MC-4D-MRI) technique that expands single image contrast 4D-MRI to a spectrum of native and synthetic image contrasts and to evaluate its feasibility in liver tumor pati ... Full text Link to item Cite

Assessing the robustness of artificial intelligence powered planning tools in radiotherapy clinical settings-a phantom simulation approach.

Journal article Quant Imaging Med Surg · December 2021 BACKGROUND: Artificial intelligence (AI) based radiotherapy treatment planning tools have gained interest in automating the treatment planning process. It is essential to understand their overall robustness in various clinical scenarios. This is an existin ... Full text Link to item Cite

Insights of an AI agent via analysis of prediction errors: a case study of fluence map prediction for radiation therapy planning.

Journal article Phys Med Biol · November 26, 2021 Purpose.We have previously reported an artificial intelligence (AI) agent that automatically generates intensity-modulated radiation therapy (IMRT) plans via fluence map prediction, by-passing inverse planning. This AI agent achieved clinically comparable ... Full text Link to item Cite

AAPM Task Group 198 Report: An implementation guide for TG 142 quality assurance of medical accelerators.

Journal article Med Phys · October 2021 The charges on this task group (TG) were as follows: (a) provide specific procedural guidelines for performing the tests recommended in TG 142; (b) provide estimate of the range of time, appropriate personnel, and qualifications necessary to complete the t ... Full text Link to item Cite

A comparison of two methodologies for radiotherapy treatment plan optimization and QA for clinical trials.

Journal article J Appl Clin Med Phys · October 2021 BACKGROUND AND PURPOSE: The efficacy of clinical trials and the outcome of patient treatment are dependent on the quality assurance (QA) of radiation therapy (RT) plans. There are two widely utilized approaches that include plan optimization guidance creat ... Full text Link to item Cite

A geometry-guided deep learning technique for CBCT reconstruction.

Journal article Phys Med Biol · July 30, 2021 Purpose.Although deep learning (DL) technique has been successfully used for computed tomography (CT) reconstruction, its implementation on cone-beam CT (CBCT) reconstruction is extremely challenging due to memory limitations. In this study, a novel DL tec ... Full text Link to item Cite

Intrinsic radiomic expression patterns after 20 Gy demonstrate early metabolic response of oropharyngeal cancers.

Journal article Med Phys · July 2021 PURPOSE: This study investigated the prognostic potential of intra-treatment PET radiomics data in patients undergoing definitive (chemo) radiation therapy for oropharyngeal cancer (OPC) on a prospective clinical trial. We hypothesized that the radiomic ex ... Full text Link to item Cite

An artificial intelligence-driven agent for real-time head-and-neck IMRT plan generation using conditional generative adversarial network (cGAN).

Journal article Med Phys · June 2021 PURPOSE: To develop an artificial intelligence (AI) agent for fully automated rapid head-and-neck intensity-modulated radiation therapy (IMRT) plan generation without time-consuming dose-volume-based inverse planning. METHODS: This AI agent was trained via ... Full text Link to item Cite

A generative adversarial network (GAN)-based technique for synthesizing realistic respiratory motion in the extended cardiac-torso (XCAT) phantoms.

Journal article Phys Med Biol · May 31, 2021 Objective. Synthesize realistic and controllable respiratory motions in the extended cardiac-torso (XCAT) phantoms by developing a generative adversarial network (GAN)-based deep learning technique.Methods. A motion generation model was developed using bic ... Full text Link to item Cite

Radiogenomic Analysis of Locally Advanced Lung Cancer Based on CT Imaging and Intratreatment Changes in Cell-Free DNA.

Journal article Radiol Imaging Cancer · April 2021 The radiologic appearance of locally advanced lung cancer may be linked to molecular changes of the disease during treatment, but characteristics of this phenomenon are poorly understood. Radiomics, liquid biopsy of cell-free DNA (cfDNA), and next-generati ... Full text Link to item Cite

An Interpretable Planning Bot for Pancreas Stereotactic Body Radiation Therapy.

Journal article Int J Radiat Oncol Biol Phys · March 15, 2021 PURPOSE: Pancreas stereotactic body radiation therapy (SBRT) treatment planning requires planners to make sequential, time-consuming interactions with the treatment planning system to reach the optimal dose distribution. We sought to develop a reinforcemen ... Full text Link to item Cite

4D radiomics: impact of 4D-CBCT image quality on radiomic analysis.

Journal article Phys Med Biol · February 11, 2021 PURPOSE: To investigate the impact of 4D-CBCT image quality on radiomic analysis and the efficacy of using deep learning based image enhancement to improve the accuracy of radiomic features of 4D-CBCT. MATERIAL AND METHODS: In this study, 4D-CT data from 1 ... Full text Link to item Cite

Evaluation of eddy current distortion and field inhomogeneity distortion corrections in MR diffusion imaging using log-demons DIR method.

Journal article Phys Med Biol · January 29, 2021 To investigate the feasibility of the log-demons deformable image registration (DIR) method to correct eddy current and field inhomogeneity distortions while preserving diffusion tensor information. Diffusion-weighted images (DWIs) are susceptible to disto ... Full text Link to item Cite

Enhancing digital tomosynthesis (DTS) for lung radiotherapy guidance using patient-specific deep learning model.

Journal article Phys Med Biol · January 26, 2021 Digital tomosynthesis (DTS) has been proposed as a fast low-dose imaging technique for image-guided radiation therapy (IGRT). However, due to the limited scanning angle, DTS reconstructed by the conventional FDK method suffers from significant distortions ... Full text Link to item Cite

Slice-stacking T2-weighted MRI for fast determination of internal target volume for liver tumor.

Journal article Quant Imaging Med Surg · January 2021 BACKGROUND: To investigate the feasibility of generating maximum intensity projection (MIP) images to determine internal target volume (ITV) using slice-stacking MRI (SS-MRI) technique. METHODS: Slice-stacking is a technique which applies a multi-slice MRI ... Full text Link to item Cite

Clinical Experience With Machine Learning-Based Automated Treatment Planning for Whole Breast Radiation Therapy.

Journal article Adv Radiat Oncol · 2021 PURPOSE: The machine learning-based automated treatment planning (MLAP) tool has been developed and evaluated for breast radiation therapy planning at our institution. We implemented MLAP for patient treatment and assessed our clinical experience for its p ... Full text Open Access Link to item Cite

Deep Learning-Based Fluence Map Prediction for Pancreas Stereotactic Body Radiation Therapy With Simultaneous Integrated Boost.

Journal article Adv Radiat Oncol · 2021 PURPOSE: Treatment planning for pancreas stereotactic body radiation therapy (SBRT) is a challenging task, especially with simultaneous integrated boost treatment approaches. We propose a deep learning (DL) framework to accurately predict fluence maps from ... Full text Link to item Cite

Outcomes in Patients With 4 to 10 Brain Metastases Treated With Dose-Adapted Single-Isocenter Multitarget Stereotactic Radiosurgery: A Prospective Study.

Journal article Adv Radiat Oncol · 2021 PURPOSE: To examine the effectiveness and safety of single-isocenter multitarget stereotactic radiosurgery using a volume-adapted dosing strategy in patients with 4 to 10 brain metastases. METHODS AND MATERIALS: Adult patients with 4 to 10 brain metastases ... Full text Link to item Cite

RETRACTED: An Encoder-Decoder Based Deep Learning AI agent for Spatial Dose Distribution Prediction: A Study of Complex Head-and-Neck IMRT Application.

Journal article Int J Radiat Oncol Biol Phys · November 1, 2020 This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This abstract has been retracted at the request of the authors. After submitting this abstract the authors realized that th ... Full text Link to item Cite

Automatic detection of pulmonary nodules on CT images with YOLOv3: development and evaluation using simulated and patient data.

Journal article Quant Imaging Med Surg · October 2020 BACKGROUND: To develop a high-efficiency pulmonary nodule computer-aided detection (CAD) method for localization and diameter estimation. METHODS: The developed CAD method centralizes a novel convolutional neural network (CNN) algorithm, You Only Look Once ... Full text Link to item Cite

Automatic detection of pulmonary nodules on CT images with YOLOv3: development and evaluation using simulated and patient data

Journal article Quantitative imaging in medicine and surgery · October 2020 Background To develop a high-efficiency pulmonary nodule computer-aided detection (CAD) method for localization and diameter estimation. Methods The developed CAD method centralizes a novel convolutional neural network (CNN) algorithm, You Only Look Once ( ... Cite

Adaptive respiratory signal prediction using dual multi-layer perceptron neural networks.

Journal article Phys Med Biol · September 14, 2020 To improve the prediction accuracy of respiratory signals by adapting the multi-layer perceptron neural network (MLP-NN) model to changing respiratory signals. We have previously developed an MLP-NN to predict respiratory signals obtained from a real-time ... Full text Link to item Cite

Automatic IMRT planning via static field fluence prediction (AIP-SFFP): a deep learning algorithm for real-time prostate treatment planning.

Journal article Phys Med Biol · September 8, 2020 The purpose of this work was to develop a deep learning (DL) based algorithm, Automatic intensity-modulated radiotherapy (IMRT) Planning via Static Field Fluence Prediction (AIP-SFFP), for automated prostate IMRT planning with real-time planning efficiency ... Full text Link to item Cite

Retrospective quality metrics review of stereotactic radiosurgery plans treating multiple targets using single-isocenter volumetric modulated arc therapy.

Journal article J Appl Clin Med Phys · June 2020 PURPOSE: To characterize key plan quality metrics in multi-target stereotactic radiosurgery (SRS) plans treated using single-isocenter volumetric modulated arc therapy (VMAT) in comparison to dynamic conformal arc (DCA) plans treating single target. To inv ... Full text Link to item Cite

Knowledge-Based Tradeoff Hyperplanes for Head and Neck Treatment Planning.

Journal article Int J Radiat Oncol Biol Phys · April 1, 2020 PURPOSE: To develop a tradeoff hyperplane model to facilitate tradeoff decision-making before inverse planning. METHODS AND MATERIALS: We propose a model-based approach to determine the tradeoff hyperplanes that allow physicians to navigate the clinically ... Full text Link to item Cite

Development of realistic multi-contrast textured XCAT (MT-XCAT) phantoms using a dual-discriminator conditional-generative adversarial network (D-CGAN).

Journal article Phys Med Biol · March 19, 2020 Develop a machine learning-based method to generate multi-contrast anatomical textures in the 4D extended cardiac-torso (XCAT) phantom for more realistic imaging simulations. As a pilot study, we synthesize CT and CBCT textures in the chest region. For tra ... Full text Link to item Cite

Digital phantoms for characterizing inconsistencies among radiomics extraction toolboxes.

Journal article Biomed Phys Eng Express · March 2, 2020 PURPOSE: to develop digital phantoms for characterizing inconsistencies among radiomics extraction methods based on three radiomics toolboxes: CERR (Computational Environment for Radiological Research), IBEX (imaging biomarker explorer), and an in-house ra ... Full text Link to item Cite

Motion robust 4D-MRI sorting based on anatomic feature matching: A digital phantom simulation study.

Journal article Radiat Med Prot · March 2020 PURPOSE: Motion artifacts induced by breathing variations are common in 4D-MRI images. This study aims to reduce the motion artifacts by developing a novel, robust 4D-MRI sorting method based on anatomic feature matching and applicable in both cine and seq ... Full text Link to item Cite

Volumetric cine magnetic resonance imaging (VC-MRI) using motion modeling, free-form deformation and multi-slice undersampled 2D cine MRI reconstructed with spatio-temporal low-rank decomposition.

Journal article Quant Imaging Med Surg · February 2020 BACKGROUND: The purpose of this study is to improve on-board volumetric cine magnetic resonance imaging (VC-MRI) using multi-slice undersampled cine images reconstructed using spatio-temporal k-space data, patient prior 4D-MRI, motion modeling (MM) and fre ... Full text Link to item Cite

A multi-scale framework with unsupervised joint training of convolutional neural networks for pulmonary deformable image registration.

Journal article Phys Med Biol · January 13, 2020 To achieve accurate and fast deformable image registration (DIR) for pulmonary CT, we proposed a Multi-scale DIR framework with unsupervised Joint training of Convolutional Neural Network (MJ-CNN). MJ-CNN contains three models at multi-scale levels for a c ... Full text Link to item Cite

Technical Note: Investigation of the dosimetric impact of stray radiation on the Common Control Unit of the IBA Blue Phantom2.

Journal article J Appl Clin Med Phys · January 2020 PURPOSE: This technical note aims to investigate the dosimetric impact of stray radiation on the Common Control Unit (CCU) of the IBA Blue Phantom2 and the measured beam data. METHODS: Three CCUs of the same model were used for the study. The primary test ... Full text Link to item Cite

Accuracy and efficiency of image-guided radiation therapy (IGRT) for preoperative partial breast radiosurgery.

Journal article J Radiosurg SBRT · 2020 OBJECTIVE: To analyze and evaluate accuracy and efficiency of IGRT process for preoperative partial breast radiosurgery. METHODS: Patients were initially setup with skin marks and 5 steps were performed: (1) Initial orthogonal 2D kV images, (2) pre-treatme ... Open Access Link to item Cite

Dose-Distribution-Driven PET Image-Based Outcome Prediction (DDD-PIOP): A Deep Learning Study for Oropharyngeal Cancer IMRT Application.

Journal article Front Oncol · 2020 PURPOSE: To develop a deep learning-based AI agent, DDD-PIOP (Dose-Distribution-Driven PET Image Outcome Prediction), for predicting 18FDG-PET image outcomes of oropharyngeal cancer (OPC) in response to intensity-modulated radiation therapy (IMRT). METHODS ... Full text Open Access Link to item Cite

NRG Oncology Survey on Practice and Technology Use in SRT and SBRT Delivery.

Journal article Front Oncol · 2020 PURPOSE: To assess stereotactic radiotherapy (SRT)/stereotactic body radiotherapy (SBRT) practices by polling clinics participating in multi-institutional clinical trials. METHODS: The NRG Oncology Medical Physics Subcommittee distributed a survey consisti ... Full text Open Access Link to item Cite

Knowledge Models as Teaching Aid for Training Intensity Modulated Radiation Therapy Planning: A Lung Cancer Case Study.

Journal article Front Artif Intell · 2020 Purpose: Artificial intelligence (AI) employs knowledge models that often behave as a black-box to the majority of users and are not designed to improve the skill level of users. In this study, we aim to demonstrate the feasibility that AI can serve as an ... Full text Link to item Cite

Fluence Map Prediction Using Deep Learning Models - Direct Plan Generation for Pancreas Stereotactic Body Radiation Therapy.

Journal article Front Artif Intell · 2020 Purpose: Treatment planning for pancreas stereotactic body radiation therapy (SBRT) is a difficult and time-consuming task. In this study, we aim to develop a novel deep learning framework to generate clinical-quality plans by direct prediction of fluence ... Full text Open Access Link to item Cite

Augmentation of CBCT Reconstructed From Under-Sampled Projections Using Deep Learning.

Journal article IEEE Trans Med Imaging · November 2019 Edges tend to be over-smoothed in total variation (TV) regularized under-sampled images. In this paper, symmetric residual convolutional neural network (SR-CNN), a deep learning based model, was proposed to enhance the sharpness of edges and detailed anato ... Full text Link to item Cite

Task Group 174 Report: Utilization of [18 F]Fluorodeoxyglucose Positron Emission Tomography ([18 F]FDG-PET) in Radiation Therapy.

Journal article Med Phys · October 2019 The use of positron emission tomography (PET) in radiation therapy (RT) is rapidly increasing in the areas of staging, segmentation, treatment planning, and response assessment. The most common radiotracer is 18 F-fluorodeoxyglucose ([18 F]FDG), a glucose ... Full text Open Access Link to item Cite

Daily edge deformation prediction using an unsupervised convolutional neural network model for low dose prior contour based total variation CBCT reconstruction (PCTV-CNN).

Journal article Biomed Phys Eng Express · October 2019 PURPOSE: Previously we developed a PCTV method to enhance the edge sharpness for low-dose CBCT reconstruction. However, the iterative deformable registration method used for deforming edges from planning-CT to on-board CBCT is time-consuming and user-depen ... Full text Link to item Cite

Modeling of multiple planning target volumes for head and neck treatments in knowledge-based treatment planning.

Journal article Med Phys · September 2019 PURPOSE: The purpose of this study is to develop an accurate and reliable dose volume histogram (DVH) prediction method for external beam radiation therapy plans with multiple planning target volumes (PTVs). MATERIALS AND METHODS: We present a novel DVH pr ... Full text Link to item Cite

LINAC based stereotactic radiosurgery for multiple brain metastases: guidance for clinical implementation.

Journal article Acta Oncol · September 2019 Introduction: Stereotactic radiosurgery (SRS) is a promising treatment option for patients with multiple brain metastases (BM). Recent technical advances have made LINAC based SRS a patient friendly technique, allowing for accurate patient positioning and ... Full text Link to item Cite

Predicting real-time 3D deformation field maps (DFM) based on volumetric cine MRI (VC-MRI) and artificial neural networks for on-board 4D target tracking: a feasibility study.

Journal article Phys Med Biol · August 21, 2019 To predict real-time 3D deformation field maps (DFMs) using Volumetric Cine MRI (VC-MRI) and adaptive boosting and multi-layer perceptron neural network (ADMLP-NN) for 4D target tracking. One phase of a prior 4D-MRI is set as the prior phase, MRIprior. Pri ... Full text Link to item Cite

An Exploratory Radiomics Approach to Quantifying Pulmonary Function in CT Images.

Journal article Sci Rep · August 8, 2019 Contemporary medical imaging is becoming increasingly more quantitative. The emerging field of radiomics is a leading example. By translating unstructured data (i.e., images) into structured data (i.e., imaging features), radiomics can potentially characte ... Full text Open Access Link to item Cite

Low dose cone-beam computed tomography reconstruction via hybrid prior contour based total variation regularization (hybrid-PCTV).

Journal article Quant Imaging Med Surg · July 2019 BACKGROUND: Previously, we developed a prior contour based total variation (PCTV) method to use edge information derived from prior images for edge enhancement in low-dose cone-beam computed tomography (CBCT) reconstruction. However, the accuracy of edge e ... Full text Link to item Cite

A robust deformable image registration enhancement method based on radial basis function.

Journal article Quant Imaging Med Surg · July 2019 BACKGROUND: To develop and evaluate a robust deformable image registration (DIR) enhancement method based on radial basis function (RBF) expansion. METHODS: To improve DIR accuracy using sparsely available measured displacements, it is crucial to estimate ... Full text Open Access Link to item Cite

Probability-based 3D k-space sorting for motion robust 4D-MRI.

Journal article Quant Imaging Med Surg · July 2019 BACKGROUND: Current 4D-MRI techniques are prone to breathing-variation-induced motion artifacts. This study developed a novel method for motion-robust multi-cycle 4D-MRI using probability-based multi-cycle sorting to overcome this deficiency. METHODS: The ... Full text Link to item Cite

A hybrid proton and hyperpolarized gas tagging MRI technique for lung respiratory motion imaging: a feasibility study.

Journal article Phys Med Biol · May 16, 2019 The aim of this work was to develop a novel hybrid 3D hyperpolarized (HP) gas tagging MRI (t-MRI) technique and to evaluate it for lung respiratory motion measurement with comparison to deformable image registrations (DIR) methods. Three healthy subjects u ... Full text Link to item Cite

First clinical retrospective investigation of limited projection CBCT for lung tumor localization in patients receiving SBRT treatment.

Journal article Phys Med Biol · May 8, 2019 To clinically investigate the limited-projection CBCT (LP-CBCT) technology for daily positioning of patients receiving breath-hold lung SBRT radiation treatment and to investigate the feasibility of reconstructing fast 4D-CBCT from 1 min 3D-CBCT scan. Elev ... Full text Link to item Cite

Genetic Single Neuron Anatomy Reveals Fine Granularity of Cortical Axo-Axonic Cells.

Journal article Cell Rep · March 12, 2019 Parsing diverse nerve cells into biological types is necessary for understanding neural circuit organization. Morphology is an intuitive criterion for neuronal classification and a proxy of connectivity, but morphological diversity and variability often pr ... Full text Link to item Cite

A Spatiotemporal-Constrained Sorting Method for Motion-Robust 4D-MRI: A Feasibility Study.

Journal article Int J Radiat Oncol Biol Phys · March 1, 2019 PURPOSE: To develop a spatiotemporal-constrained sorting technique for motion-robust 4 dimensional-magnetic resonance imaging. METHODS AND MATERIALS: This sorting method implemented 2 new approaches for 4-dimensional imaging: (1) an optimized sparse k-spac ... Full text Link to item Cite

Evaluation of dosimetric uncertainty caused by MR geometric distortion in MRI-based liver SBRT treatment planning.

Journal article J Appl Clin Med Phys · February 2019 PURPOSE: MRI-based treatment planning is a promising technique for liver stereotactic-body radiation therapy (SBRT) treatment planning to improve target volume delineation and reduce radiation dose to normal tissues. MR geometric distortion, however, is a ... Full text Open Access Link to item Cite

Association of pre-treatment radiomic features with lung cancer recurrence following stereotactic body radiation therapy.

Journal article Phys Med Biol · January 8, 2019 The purpose of this work was to investigate the potential relationship between radiomic features extracted from pre-treatment x-ray CT images and clinical outcomes following stereotactic body radiation therapy (SBRT) for non-small-cell lung cancer (NSCLC). ... Full text Open Access Link to item Cite

The effect of setup uncertainty on optimal dosimetric margin in LINAC-based stereotactic radiosurgery with dynamic conformal arc technique.

Journal article J Radiosurg SBRT · 2019 PURPOSE: To estimate the combined effect of setup uncertainty on optimal dosimetric margin by analyzing the dose distribution and biological effect in LINAC-based stereotactic radiosurgery (SRS) with dynamic conformal arc (DCA) technique. METHODS: SRS trea ... Link to item Cite

Impact of Esophageal Motion on Dosimetry and Toxicity With Thoracic Radiation Therapy.

Journal article Technol Cancer Res Treat · 2019 PURPOSE: To investigate the impact of intra- and inter-fractional esophageal motion on dosimetry and observed toxicity in a phase I dose escalation study of accelerated radiotherapy with concurrent chemotherapy for locally advanced lung cancer. METHODS AND ... Full text Open Access Link to item Cite

Data clustering based on Langevin annealing with a self-consistent potential

Journal article Quarterly of Applied Mathematics · January 1, 2019 This paper introduces a novel data clustering algorithm based on Langevin dynamics, where the associated potential is constructed directly from the data. To introduce a self-consistent potential, we adopt the potential model from the established Quantum Cl ... Full text Open Access Cite

Knowledge-Based Statistical Inference Method for Plan Quality Quantification.

Journal article Technol Cancer Res Treat · January 1, 2019 AIM: The aim of the study is to develop a geometrically adaptive and statistically robust plan quality inference method. METHODS AND MATERIALS: We propose a knowledge-based plan quality inference method that references to similar plans in the historical da ... Full text Open Access Link to item Cite

Goal-Driven Beam Setting Optimization for Whole-Breast Radiation Therapy.

Journal article Technol Cancer Res Treat · January 1, 2019 PURPOSE: To develop an automated optimization program to generate optimal beam settings for whole-breast radiation therapy driven by clinically oriented goals. MATERIALS AND METHODS: Forty patients were retrospectively included in this study. Each patient' ... Full text Open Access Link to item Cite

Automatic Planning of Whole Breast Radiation Therapy Using Machine Learning Models.

Journal article Front Oncol · 2019 Purpose: To develop an automatic treatment planning system for whole breast radiation therapy (WBRT) based on two intensity-modulated tangential fields, enabling near-real-time planning. Methods and Materials: A total of 40 WBRT plans from a single institu ... Full text Open Access Link to item Cite

Incorporating Case-Based Reasoning for Radiation Therapy Knowledge Modeling: A Pelvic Case Study.

Journal article Technol Cancer Res Treat · January 1, 2019 Knowledge models in radiotherapy capture the relation between patient anatomy and dosimetry to provide treatment planning guidance. When treatment schemes evolve, existing models struggle to predict accurately. We propose a case-based reasoning framework d ... Full text Open Access Link to item Cite

The effect of MLC leaf width in single-isocenter multi-target radiosurgery with volumetric modulated arc therapy.

Journal article J Radiosurg SBRT · 2019 PURPOSE: Single-isocenter multi-target (SIMT) volumetric modulated arc therapy (VMAT) is primarily limited to linear accelerators utilizing 2.5 mm leaf width MLCs. We explore feasibility of applying this technique to linear accelerators utilizing MLCs with ... Open Access Link to item Cite

An investigation of machine learning methods in delta-radiomics feature analysis.

Journal article PLoS One · 2019 PURPOSE: This study aimed to investigate the effectiveness of using delta-radiomics to predict overall survival (OS) for patients with recurrent malignant gliomas treated by concurrent stereotactic radiosurgery and bevacizumab, and to investigate the effec ... Full text Open Access Link to item Cite

An initial investigation of hyperpolarized gas tagging magnetic resonance imaging in evaluating deformable image registration-based lung ventilation.

Journal article Med Phys · December 2018 BACKGROUND: Deformable image registration (DIR)-based lung ventilation mapping is attractive due to its simplicity, and also challenging due to its susceptibility to errors and uncertainties. In this study, we explored the use of 3D Hyperpolarized (HP) gas ... Full text Link to item Cite

Association of Interim FDG-PET Imaging During Chemoradiation for Squamous Anal Canal Carcinoma With Recurrence.

Journal article Int J Radiat Oncol Biol Phys · November 15, 2018 PURPOSE: Imaging parameters from 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) before and after chemoradiation therapy (CRT) for anal canal cancer correlate with clinical outcomes. This prospective, hypothesis-generating pilot study inv ... Full text Link to item Cite

Spatial-temporal variability of radiomic features and its effect on the classification of lung cancer histology.

Journal article Phys Med Biol · November 8, 2018 The purpose of this research was to study the sensitivity of Computed Tomography (CT) radiomic features to motion blurring and signal-to-noise ratios (SNR), and investigate its downstream effect regarding the classification of non-small cell lung cancer (N ... Full text Open Access Link to item Cite

Effect of machine learning methods on predicting NSCLC overall survival time based on Radiomics analysis.

Journal article Radiat Oncol · October 5, 2018 BACKGROUND: To investigate the effect of machine learning methods on predicting the Overall Survival (OS) for non-small cell lung cancer based on radiomics features analysis. METHODS: A total of 339 radiomic features were extracted from the segmented tumor ... Full text Open Access Link to item Cite

Lung IMRT planning with automatic determination of beam angle configurations.

Journal article Phys Med Biol · July 6, 2018 Beam angle configuration is a major planning decision in intensity modulated radiation treatment (IMRT) that has a significant impact on dose distributions and thus quality of treatment, especially in complex planning cases such as those for lung cancer tr ... Full text Link to item Cite

Iterative inversion of deformation vector fields with feedback control.

Journal article Med Phys · July 2018 PURPOSE: Often, the inverse deformation vector field (DVF) is needed together with the corresponding forward DVF in four-dimesional (4D) reconstruction and dose calculation, adaptive radiation therapy, and simultaneous deformable registration. This study a ... Full text Link to item Cite

A Novel method to generate on-board 4D MRI using prior 4D MRI and on-board kV projections from a conventional LINAC for target localization in liver SBRT.

Journal article Med Phys · July 2018 PURPOSE: On-board MRI can provide superb soft tissue contrast for improving liver SBRT localization. However, the availability of on-board MRI in clinics is extremely limited. On the contrary, on-board kV imaging systems are widely available on radiotherap ... Full text Link to item Cite

Low dose CBCT reconstruction via prior contour based total variation (PCTV) regularization: a feasibility study.

Journal article Phys Med Biol · April 19, 2018 PURPOSE: compressed sensing reconstruction using total variation (TV) tends to over-smooth the edge information by uniformly penalizing the image gradient. The goal of this study is to develop a novel prior contour based TV (PCTV) method to enhance the edg ... Full text Link to item Cite

Improving Quality and Consistency in NRG Oncology Radiation Therapy Oncology Group 0631 for Spine Radiosurgery via Knowledge-Based Planning.

Journal article Int J Radiat Oncol Biol Phys · March 15, 2018 PURPOSE: To use knowledge-based planning (KBP) as a method of producing high-quality, consistent, protocol-compliant treatment plans in a complex setting of spine stereotactic body radiation therapy on NRG Oncology Radiation Therapy Oncology Group (RTOG) 0 ... Full text Link to item Cite

Application of the 4-D XCAT Phantoms in Biomedical Imaging and Beyond.

Journal article IEEE Trans Med Imaging · March 2018 The four-dimensional (4-D) eXtended CArdiac-Torso (XCAT) series of phantoms was developed to provide accurate computerized models of the human anatomy and physiology. The XCAT series encompasses a vast population of phantoms of varying ages from newborn to ... Full text Link to item Cite

Image acquisition optimization of a limited-angle intrafraction verification (LIVE) system for lung radiotherapy.

Journal article Med Phys · January 2018 PURPOSE: Limited-angle intrafraction verification (LIVE) has been previously developed for four-dimensional (4D) intrafraction target verification either during arc delivery or between three-dimensional (3D)/IMRT beams. Preliminary studies showed that LIVE ... Full text Link to item Cite

Principal component reconstruction (PCR) for cine CBCT with motion learning from 2D fluoroscopy.

Journal article Med Phys · January 2018 PURPOSE: This work aims to generate cine CT images (i.e., 4D images with high-temporal resolution) based on a novel principal component reconstruction (PCR) technique with motion learning from 2D fluoroscopic training images. METHODS: In the proposed PCR m ... Full text Link to item Cite

An Ensemble Approach to Knowledge-Based Intensity-Modulated Radiation Therapy Planning.

Journal article Front Oncol · 2018 Knowledge-based planning (KBP) utilizes experienced planners' knowledge embedded in prior plans to estimate optimal achievable dose volume histogram (DVH) of new cases. In the regression-based KBP framework, previously planned patients' anatomical features ... Full text Open Access Link to item Cite

Assessment of concurrent stereotactic radiosurgery and bevacizumab treatment of recurrent malignant gliomas using multi-modality MRI imaging and radiomics analysis.

Journal article J Radiosurg SBRT · 2018 PURPOSE: To assess the response and predict the overall survival (OS) of recurrent malignant gliomas (MG) patients treated with concurrent BVZ/SRS using multi-modality MRI imaging and radiomics analysis.Methods and materials: SRS was delivered in a single ... Link to item Cite

Dosimetric Characterization of an Intensity-modulated X-Ray Brachytherapy System.

Journal article J Med Phys · 2018 PURPOSE: An intensity-modulated X-ray brachytherapy system is being developed for various clinical applications. This new system makes it possible for clinical staff to control energy as well as dose rate for different tumor sites according to their sizes ... Full text Link to item Cite

Accelerating volumetric cine MRI (VC-MRI) using undersampling for real-time 3D target localization/tracking in radiation therapy: a feasibility study.

Journal article Phys Med Biol · December 14, 2017 PURPOSE: To accelerate volumetric cine MRI (VC-MRI) using undersampled 2D-cine MRI to provide real-time 3D guidance for gating/target tracking in radiotherapy. METHODS: 4D-MRI is acquired during patient simulation. One phase of the prior 4D-MRI is selected ... Full text Link to item Cite

Clinical Study of Orthogonal-View Phase-Matched Digital Tomosynthesis for Lung Tumor Localization.

Journal article Technol Cancer Res Treat · December 2017 BACKGROUND AND PURPOSE: Compared to cone-beam computed tomography, digital tomosynthesis imaging has the benefits of shorter scanning time, less imaging dose, and better mechanical clearance for tumor localization in radiation therapy. However, for lung tu ... Full text Link to item Cite

Characterization of Water-Clear Polymeric Gels for Use as Radiotherapy Bolus.

Journal article Technol Cancer Res Treat · December 2017 Our purpose was to investigate polymeric gels for use as a highly transparent radiotherapy bolus and determine the relevant physical and dosimetric properties. We first quantified tensile properties (maximum stress, strain, and Young modulus) for various p ... Full text Link to item Cite

Development of a Computerized 4-D MRI Phantom for Liver Motion Study.

Journal article Technol Cancer Res Treat · December 2017 PURPOSE: To develop a 4-dimensional computerized magnetic resonance imaging phantom with image textures extracted from real patient scans for liver motion studies. METHODS: The proposed phantom was developed based on the current version of 4-dimensional ex ... Full text Link to item Cite

Dosimetric Analysis of Microscopic Disease in SBRT for Lung Cancers.

Journal article Technol Cancer Res Treat · December 2017 OBJECTIVE: The objective of this study is to theoretically and experimentally evaluate the dosimetry in the microscopic disease regions surrounding the tumor under stereotactic body radiation therapy of lung cancer. METHODS: For simplicity, the tumor was c ... Full text Link to item Cite

Outlier identification in radiation therapy knowledge-based planning: A study of pelvic cases.

Journal article Med Phys · November 2017 PURPOSE: The purpose of this study was to apply statistical metrics to identify outliers and to investigate the impact of outliers on knowledge-based planning in radiation therapy of pelvic cases. We also aimed to develop a systematic workflow for identify ... Full text Link to item Cite

Biopsy of enlarging lesions after stereotactic radiosurgery for brain metastases frequently reveals radiation necrosis.

Journal article Neuro Oncol · October 1, 2017 BACKGROUND: Stereotactic radiosurgery (SRS) offers excellent local control for brain metastases (BM) with low rates of toxicity. Radiation necrosis (RN) may occur after treatment and is challenging to distinguish from local recurrence (LR). We evaluated en ... Full text Link to item Cite

AAPM-RSS Medical Physics Practice Guideline 9.a. for SRS-SBRT.

Journal article J Appl Clin Med Phys · September 2017 The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8,000 members and is the princi ... Full text Link to item Cite

Respiratory signal prediction based on adaptive boosting and multi-layer perceptron neural network.

Journal article Phys Med Biol · August 3, 2017 To improve the prediction accuracy of respiratory signals using adaptive boosting and multi-layer perceptron neural network (ADMLP-NN) for gated treatment of moving target in radiation therapy. The respiratory signals acquired using a real-time position ma ... Full text Link to item Cite

Accelerated Brain DCE-MRI Using Iterative Reconstruction With Total Generalized Variation Penalty for Quantitative Pharmacokinetic Analysis: A Feasibility Study.

Journal article Technol Cancer Res Treat · August 2017 PURPOSE: To investigate the feasibility of using undersampled k-space data and an iterative image reconstruction method with total generalized variation penalty in the quantitative pharmacokinetic analysis for clinical brain dynamic contrast-enhanced magne ... Full text Link to item Cite

Exploring the Margin Recipe for Online Adaptive Radiation Therapy for Intermediate-Risk Prostate Cancer: An Intrafractional Seminal Vesicles Motion Analysis.

Journal article Int J Radiat Oncol Biol Phys · June 1, 2017 PURPOSE: To provide a benchmark for seminal vesicle (SV) margin selection to account for intrafractional motion and to investigate the effectiveness of 2 motion surrogates in predicting intrafractional SV coverage. METHODS AND MATERIALS: Fifteen prostate p ... Full text Link to item Cite

Reducing scan angle using adaptive prior knowledge for a limited-angle intrafraction verification (LIVE) system for conformal arc radiotherapy.

Journal article Phys Med Biol · May 7, 2017 The purpose of this study is to develop an adaptive prior knowledge guided image estimation technique to reduce the scan angle needed in the limited-angle intrafraction verification (LIVE) system for 4D-CBCT reconstruction. The LIVE system has been previou ... Full text Link to item Cite

Quantitative Approach to Failure Mode and Effect Analysis for Linear Accelerator Quality Assurance.

Journal article Int J Radiat Oncol Biol Phys · May 1, 2017 PURPOSE: To determine clinic-specific linear accelerator quality assurance (QA) TG-142 test frequencies, to maximize physicist time efficiency and patient treatment quality. METHODS AND MATERIALS: A novel quantitative approach to failure mode and effect an ... Full text Link to item Cite

Retrospective four-dimensional magnetic resonance imaging with image-based respiratory surrogate: a sagittal-coronal-diaphragm point of intersection motion tracking method.

Journal article J Med Imaging (Bellingham) · April 2017 A four-dimensional magnetic resonance imaging (4-D-MRI) technique with Sagittal-Coronal-Diaphragm Point-of-Intersection (SCD-PoI) as a respiratory surrogate is proposed. To develop an image-based respiratory surrogate, the SCD-PoI motion tracking method is ... Full text Link to item Cite

Estimating 4D-CBCT from prior information and extremely limited angle projections using structural PCA and weighted free-form deformation for lung radiotherapy.

Journal article Med Phys · March 2017 PURPOSE: To investigate the feasibility of using structural-based principal component analysis (PCA) motion-modeling and weighted free-form deformation to estimate on-board 4D-CBCT using prior information and extremely limited angle projections for potenti ... Full text Link to item Cite

Four-dimensional diffusion-weighted MR imaging (4D-DWI): a feasibility study.

Journal article Med Phys · February 2017 PURPOSE: Diffusion-weighted Magnetic Resonance Imaging (DWI) has been shown to be a powerful tool for cancer detection with high tumor-to-tissue contrast. This study aims to investigate the feasibility of developing a four-dimensional DWI technique (4D-DWI ... Full text Link to item Cite

Impact of moving target on measurement accuracy in 3D and 4D PET imaging-a phantom study.

Journal article Adv Radiat Oncol · 2017 PURPOSE: The purpose of this study was to evaluate the impact of tumor motion on maximum standardized uptake value (SUVmax) and metabolic tumor volume (MTV) measurements in both 3-dimensional and respiratory-correlated, 4-dimensional positron emission tomo ... Full text Link to item Cite

An in-house protocol for improved flood field calibration of TrueBeam FFF cine imaging.

Journal article J Appl Clin Med Phys · January 2017 PURPOSE: TrueBeams equipped with the 40 × 30 cm2 Electronic Portal Imaging Devices (EPIDs) are prone to image saturation at the image center when used with flattening filter free (FFF) photon energies. While cine imaging during treatment may not saturate b ... Full text Link to item Cite

Single fraction stereotactic radiosurgery for multiple brain metastases.

Journal article Adv Radiat Oncol · 2017 INTRODUCTION: Due to the neurocognitive side effects of whole brain radiation therapy (WBRT), stereotactic radiosurgery (SRS) is being used with increasing frequency. The use of SRS is expanding for patients with multiple (>4) brain metastases (BM). This s ... Full text Open Access Link to item Cite

Markerless Four-Dimensional-Cone Beam Computed Tomography Projection-Phase Sorting Using Prior Knowledge and Patient Motion Modeling: A Feasibility Study.

Journal article Cancer Transl Med · 2017 AIM: During cancer radiotherapy treatment, on-board four-dimensional-cone beam computed tomography (4D-CBCT) provides important patient 4D volumetric information for tumor target verification. Reconstruction of 4D-CBCT images requires sorting of acquired p ... Open Access Link to item Cite

Sensitivity of 3D Dose Verification to Multileaf Collimator Misalignments in Stereotactic Body Radiation Therapy of Spinal Tumor.

Journal article Technol Cancer Res Treat · December 2016 PURPOSE: This study aimed to detect the sensitivity of Delt 4 on ordinary field multileaf collimator misalignments, system misalignments, random misalignments, and misalignments caused by gravity of the multileaf collimator in stereotactic body radiation t ... Full text Link to item Cite

A probability-based multi-cycle sorting method for 4D-MRI: A simulation study.

Journal article Med Phys · December 2016 PURPOSE: To develop a novel probability-based sorting method capable of generating multiple breathing cycles of 4D-MRI images and to evaluate performance of this new method by comparing with conventional phase-based methods in terms of image quality and tu ... Full text Link to item Cite

Comparisons of volumetric modulated arc therapy (VMAT) quality assurance (QA) systems: sensitivity analysis to machine errors.

Journal article Radiat Oncol · November 7, 2016 BACKGROUND: In volumetric modulated arc therapy (VMAT), gantry angles, dose rate and the MLC positions vary with the radiation delivery. The quality assurance (QA) system should be able to catch the planning and machine errors. The aim of this study was to ... Full text Open Access Link to item Cite

Assessment of Treatment Response With Diffusion-Weighted MRI and Dynamic Contrast-Enhanced MRI in Patients With Early-Stage Breast Cancer Treated With Single-Dose Preoperative Radiotherapy: Initial Results.

Journal article Technol Cancer Res Treat · October 2016 Single-dose preoperative stereotactic body radiotherapy is a novel radiotherapy technique for the early-stage breast cancer, and the treatment response pattern of this technique needs to be investigated on a quantitative basis. In this work, dynamic contra ... Full text Link to item Cite

Simultaneous 4D-CBCT reconstruction with sliding motion constraint.

Journal article Med Phys · October 2016 PURPOSE: Current approaches using deformable vector field (DVF) for motion-compensated 4D-cone beam CT (CBCT) reconstruction typically utilize an isotropically smoothed DVF between different respiration phases. Such isotropically smoothed DVF does not work ... Full text Link to item Cite

Re-examining TG-142 recommendations in light of modern techniques for linear accelerator based radiosurgery.

Journal article Med Phys · October 2016 PURPOSE: The recent development of multifocal stereotactic radiosurgery (SRS) using a single isocenter volumetric modulated arc theory (VMAT) technique warrants a re-examination of the quality assurance (QA) tolerances for routine mechanical QA recommended ... Full text Link to item Cite

Diode-based transmission detector for IMRT delivery monitoring: a validation study.

Journal article J Appl Clin Med Phys · September 8, 2016 The purpose of this work was to evaluate the potential of a new transmission detector for real-time quality assurance of dynamic-MLC-based radiotherapy. The accuracy of detecting dose variation and static/dynamic MLC position deviations was measured, as we ... Full text Open Access Link to item Cite

Diode-based transmission detector for IMRT delivery monitoring: a validation study.

Journal article J Appl Clin Med Phys · September 2016 The purpose of this work was to evaluate the potential of a new transmission detector for real-time quality assurance of dynamic-MLC-based radiotherapy. The accuracy of detecting dose variation and static/dynamic MLC position deviations was measured, as we ... Full text Link to item Cite

Evaluation of the effect of transcytolemmal water exchange analysis for therapeutic response assessment using DCE-MRI: a comparison study.

Journal article Phys Med Biol · July 7, 2016 This study compares the shutter-speed (SS) and the Tofts models as used in assessing therapeutic response in a longitudinal DCE-MRI experiment. Sixteen nu/nu mice with implanted colorectal adenocarcinoma cell line (LS-174T) were randomly assigned into trea ... Full text Link to item Cite

Scatter Reduction and Correction for Dual-Source Cone-Beam CT Using Prepatient Grids.

Journal article Technol Cancer Res Treat · June 2016 PURPOSE: Scatter significantly limits the application of the dual-source cone-beam computed tomography by inducing scatter artifacts and degrading contrast-to-noise ratio, Hounsfield-unit accuracy, and image uniformity. Although our previously developed in ... Full text Link to item Cite

A Technique for Generating Volumetric Cine-Magnetic Resonance Imaging.

Journal article Int J Radiat Oncol Biol Phys · June 1, 2016 PURPOSE: The purpose of this study was to develop a techique to generate on-board volumetric cine-magnetic resonance imaging (VC-MRI) using patient prior images, motion modeling, and on-board 2-dimensional cine MRI. METHODS AND MATERIALS: One phase of a 4- ... Full text Link to item Cite

Dynamic fractal signature dissimilarity analysis for therapeutic response assessment using dynamic contrast-enhanced MRI.

Journal article Med Phys · March 2016 PURPOSE: To develop a dynamic fractal signature dissimilarity (FSD) method as a novel image texture analysis technique for the quantification of tumor heterogeneity information for better therapeutic response assessment with dynamic contrast-enhanced (DCE) ... Full text Link to item Cite

An efficient calculation method for pharmacokinetic parameters in brain permeability study using dynamic contrast-enhanced MRI.

Journal article Magn Reson Med · February 2016 PURPOSE: To develop an efficient method for calculating pharmacokinetic (PK) parameters in brain DCE-MRI permeability studies. METHODS: A linear least-squares fitting algorithm based on a derivative expression of the two-compartment PK model was proposed t ... Full text Link to item Cite

On the sensitivity of TG-119 and IROC credentialing to TPS commissioning errors.

Journal article J Appl Clin Med Phys · January 8, 2016 We investigate the sensitivity of IMRT commissioning using the TG-119 C-shape phantom and credentialing with the IROC head and neck phantom to treatment planning system commissioning errors. We introduced errors into the various aspects of the commissionin ... Full text Open Access Link to item Cite

Accuracy of respiratory motion measurement of 4D-MRI: A comparison between cine and sequential acquisition.

Journal article Med Phys · January 2016 PURPOSE: The authors have recently developed a cine-mode T2*/T1-weighted 4D-MRI technique and a sequential-mode T2-weighted 4D-MRI technique for imaging respiratory motion. This study aims at investigating which 4D-MRI image acquisition mode, cine or seque ... Full text Link to item Cite

On the sensitivity of TG-119 and IROC credentialing to TPS commissioning errors.

Journal article J Appl Clin Med Phys · January 2016 We investigate the sensitivity of IMRT commissioning using the TG-119 C-shape phantom and credentialing with the IROC head and neck phantom to treatment planning system commissioning errors. We introduced errors into the various aspects of the commissionin ... Full text Link to item Cite

Novel Technologies for Improved Treatment Outcome and Patient Safety in Cancer Radiotherapy.

Journal article Biomed Res Int · 2016 Full text Link to item Cite

Atlas-guided prostate intensity modulated radiation therapy (IMRT) planning.

Journal article Phys Med Biol · September 21, 2015 An atlas-based IMRT planning technique for prostate cancer was developed and evaluated. A multi-dose atlas was built based on the anatomy patterns of the patients, more specifically, the percent distance to the prostate and the concaveness angle formed by ... Full text Link to item Cite

T2-weighted four dimensional magnetic resonance imaging with result-driven phase sorting.

Journal article Med Phys · August 2015 PURPOSE: T2-weighted MRI provides excellent tumor-to-tissue contrast for target volume delineation in radiation therapy treatment planning. This study aims at developing a novel T2-weighted retrospective four dimensional magnetic resonance imaging (4D-MRI) ... Full text Link to item Cite

Dosimetric verification of lung cancer treatment using the CBCTs estimated from limited-angle on-board projections.

Journal article Med Phys · August 2015 PURPOSE: Lung cancer treatment is susceptible to treatment errors caused by interfractional anatomical and respirational variations of the patient. On-board treatment dose verification is especially critical for the lung stereotactic body radiation therapy ... Full text Link to item Cite

Utilizing knowledge from prior plans in the evaluation of quality assurance.

Journal article Phys Med Biol · June 21, 2015 Increased interest regarding sensitivity of pre-treatment intensity modulated radiotherapy and volumetric modulated arc radiotherapy (VMAT) quality assurance (QA) to delivery errors has led to the development of dose-volume histogram (DVH) based analysis. ... Full text Link to item Cite

TH-CD-207-09: Retrospective 4D-MRI with a Novel Image-Based Surrogate: A Sagittal-Coronal-Diaphragm Point of Intersection (SCD-PoI) Motion Tracking Method.

Journal article Med Phys · June 2015 PURPOSE: The unreliable stability of internal respiratory surrogates and inconvenience of external respiratory surrogates for current retrospective 4D-MRI techniques largely affects the image quality of 4D-MRI. This study aims at developing image-based sur ... Full text Link to item Cite

TH-CD-204-10: Probability-Driven Sorting Method for Reconstructing Variation-Independent 4D-MRI.

Journal article Med Phys · June 2015 PURPOSE: To develop a novel probability-driven sorting method that inherently incorporates breathing variations in the sorting process and 4D reconstruction. METHODS: The probability-driven sorting method has two key steps: (a) determination of multiple pr ... Full text Link to item Cite

TH-CD-204-09: Physiological Modeling of Lung Motion Based On Hyperpolarized Gas Tagging MRI.

Journal article Med Phys · June 2015 PURPOSE: To model the respiratory motion of lung based on the physiological ground truth measured with hyperpolarized (HP) gas tagging magnetic resonance imaging (MRI). METHODS: A novel 4D model was established to investigate the respiratory motion of lung ... Full text Link to item Cite

WE-AB-BRA-11: Development of Physiological-Based Virtual Thorax Phantoms for Evaluation of Deformable Image Registration.

Journal article Med Phys · June 2015 PURPOSE: To develop a methodology of constructing physiological-based virtual thorax phantom based on hyperpolarized (HP) gas tagging MRI for evaluating deformable image registration (DIR). METHODS: Three healthy subjects were imaged at both the end-of-inh ... Full text Link to item Cite

WE-AB-BRA-03: Displacement Vector Field (DVF) Error Correction Using Sparsely Distributed Ground-Truth Displacement Vectors.

Journal article Med Phys · June 2015 PURPOSE: This study aims to develop a technique capable of reducing errors in deformable image registration (DIR) by integrating information of sparsely distributed ground-truth displacement vectors into a dense DVF. METHODS: An in-house developed lung mot ... Full text Link to item Cite

SU-E-J-223: A BOLD Contrast Imaging Sequence to Evaluate Oxygenation Changes Due to Breath Holding for Breast Radiotherapy: A Pilot Study.

Journal article Med Phys · June 2015 PURPOSE: To develop a robust MRI sequence to measure BOLD breath hold induced contrast in context of breast radiotherapy. METHODS: Two sequences were selected from prior studies as candidates to measure BOLD contrast attributable to breath holding within t ... Full text Link to item Cite

SU-D-BRA-01: Therapeutic Response Assessment Using a Novel Gray Level Local Power Matrix (GLLPM) in DCE-MRI Texture Analysis: Feasibility Study.

Journal article Med Phys · June 2015 PURPOSE: Most current DCE-MRI texture analysis methods focus on the spatial information of chosen contrast-enhanced MR volumes or pharmacokinetic (PK) parameter maps, and the temporal information is not well included. This work proposed a novel texture mat ... Full text Link to item Cite

TU-AB-303-06: Does Online Adaptive Radiation Therapy Mean Zero Margin for Intermediate-Risk Prostate Cancer? An Intra-Fractional Seminal Vesicles Motion Analysis.

Journal article Med Phys · June 2015 PURPOSE: To provide benchmark for seminal vesicles (SVs) margin selection to account for intra-fractional motion; and to investigate the effectiveness of two motion surrogates in predicting intra-fractional SV underdosage. METHODS: 9 prostate SBRT patients ... Full text Link to item Cite

SU-E-T-690: Sensitivity Analysis to Machine Error: Comparisons of VMAT QA Systems.

Journal article Med Phys · June 2015 PURPOSE: In VMAT delivery, the gantry angles, dose rate and the MLC positions are all modulated. It is therefore necessary to perform pre-treatment QA to detect any possible errors either in the plan or machine delivery system. Previously we developed a QA ... Full text Link to item Cite

Flattening filter-free accelerators: a report from the AAPM Therapy Emerging Technology Assessment Work Group.

Journal article J Appl Clin Med Phys · May 8, 2015 This report describes the current state of flattening filter-free (FFF) radiotherapy beams implemented on conventional linear accelerators, and is aimed primarily at practicing medical physicists. The Therapy Emerging Technology Assessment Work Group of th ... Full text Open Access Link to item Cite

A Monte Carlo simulation framework for electron beam dose calculations using Varian phase space files for TrueBeam Linacs.

Journal article Med Phys · May 2015 PURPOSE: To develop a framework for accurate electron Monte Carlo dose calculation. In this study, comprehensive validations of vendor provided electron beam phase space files for Varian TrueBeam Linacs against measurement data are presented. METHODS: In t ... Full text Link to item Cite

Preliminary clinical evaluation of a 4D-CBCT estimation technique using prior information and limited-angle projections.

Journal article Radiother Oncol · April 2015 BACKGROUND AND PURPOSE: A technique has been previously reported to estimate high-quality 4D-CBCT using prior information and limited-angle projections. This study is to investigate its clinical feasibility through both phantom and patient studies. MATERIA ... Full text Link to item Cite

Quantitative comparison of automatic and manual IMRT optimization for prostate cancer: the benefits of DVH prediction.

Journal article J Appl Clin Med Phys · March 8, 2015 A recent publication indicated that the patient anatomical feature (PAF) model was capable of predicting optimal objectives based on past experience. In this study, the benefits of IMRT optimization using PAF-predicted objectives as guidance for prostate w ... Full text Open Access Link to item Cite

Standardized beam bouquets for lung IMRT planning.

Journal article Phys Med Biol · March 7, 2015 The selection of the incident angles of the treatment beams is a critical component of intensity modulated radiation therapy (IMRT) planning for lung cancer due to significant variations in tumor location, tumor size and patient anatomy. We investigate the ... Full text Link to item Cite

From active shape model to active optical flow model: a shape-based approach to predicting voxel-level dose distributions in spine SBRT.

Journal article Phys Med Biol · March 7, 2015 Prediction of achievable dose distribution in spine stereotactic body radiation therapy (SBRT) can help in designing high-quality treatment plans to maximally protect spinal cords and to effectively control tumours. Dose distributions at spinal cords are p ... Full text Link to item Cite

Four dimensional magnetic resonance imaging with retrospective k-space reordering: a feasibility study.

Journal article Med Phys · February 2015 PURPOSE: Current four dimensional magnetic resonance imaging (4D-MRI) techniques lack sufficient temporal/spatial resolution and consistent tumor contrast. To overcome these limitations, this study presents the development and initial evaluation of a new s ... Full text Link to item Cite

Dosimetric comparison of preoperative single-fraction partial breast radiotherapy techniques: 3D CRT, noncoplanar IMRT, coplanar IMRT, and VMAT.

Journal article J Appl Clin Med Phys · January 8, 2015 The purpose of this study was to compare dosimetric parameters of treatment plans among four techniques for preoperative single-fraction partial breast radiotherapy in order to select an optimal treatment technique. The techniques evaluated were noncoplana ... Full text Link to item Cite

Impact of dose calculation accuracy during optimization on lung IMRT plan quality.

Journal article J Appl Clin Med Phys · January 8, 2015 The purpose of this study was to evaluate the effect of dose calculation accuracy and the use of an intermediate dose calculation step during the optimization of intensity-modulated radiation therapy (IMRT) planning on the final plan quality for lung cance ... Full text Link to item Cite

Defining the optimal planning target volume in image-guided stereotactic radiosurgery of brain metastases: results of a randomized trial.

Journal article Int J Radiat Oncol Biol Phys · January 1, 2015 PURPOSE: To identify an optimal margin about the gross target volume (GTV) for stereotactic radiosurgery (SRS) of brain metastases, minimizing toxicity and local recurrence. METHODS AND MATERIALS: Adult patients with 1 to 3 brain metastases less than 4 cm ... Full text Link to item Cite

Quality assurance for online adapted treatment plans: benchmarking and delivery monitoring simulation.

Journal article Med Phys · January 2015 PURPOSE: An important challenge facing online adaptive radiation therapy is the development of feasible and efficient quality assurance (QA). This project aimed to validate the deliverability of online adapted plans and develop a proof-of-concept online de ... Full text Link to item Cite

Dosimetric comparison of preoperative single-fraction partial breast radiotherapy techniques: 3D CRT, noncoplanar IMRT, coplanar IMRT, and VMAT

Journal article Journal of Applied Clinical Medical Physics · January 1, 2015 The purpose of this study was to compare dosimetric parameters of treatment plans among four techniques for preoperative single-fraction partial breast radiotherapy in order to select an optimal treatment technique. The techniques evaluated were noncoplana ... Cite

An active optical flow model for dose prediction in spinal sbrt plans

Journal article Lecture Notes in Computational Vision and Biomechanics · January 1, 2015 Accurate dose predication is critical to spinal stereotactic body radiation therapy (SBRT). It enables radiation oncologists and planners to design treatment plans that maximally protect spinal cord while effectively controlling surrounding tumors. Spinal ... Full text Cite

Quantitative comparison of automatic and manual IMRT optimization for prostate cancer: The benefits of DVH prediction

Journal article Journal of Applied Clinical Medical Physics · January 1, 2015 A recent publication indicated that the patient anatomical feature (PAF) model was capable of predicting optimal objectives based on past experience. In this study, the benefits of IMRT optimization using PAF-predicted objectives as guidance for prostate w ... Full text Cite

Is diaphragm motion a good surrogate for liver tumor motion?

Journal article Int J Radiat Oncol Biol Phys · November 15, 2014 PURPOSE: To evaluate the relationship between liver tumor motion and diaphragm motion. METHODS AND MATERIALS: Fourteen patients with hepatocellular carcinoma (10 of 14) or liver metastases (4 of 14) undergoing radiation therapy were included in this study. ... Full text Link to item Cite

A hardware investigation of robotic SPECT for functional and molecular imaging onboard radiation therapy systems.

Journal article Med Phys · November 2014 PURPOSE: To construct a robotic SPECT system and to demonstrate its capability to image a thorax phantom on a radiation therapy flat-top couch, as a step toward onboard functional and molecular imaging in radiation therapy. METHODS: A robotic SPECT imaging ... Full text Link to item Cite

BM-17 * FINAL RESULTS OF A RANDOMIZED TRIAL TO IDENTIFY THE OPTIMAL PLANNING TARGET VOLUME IN IMAGE-GUIDED STEREOTACTIC RADIOSURGERY OF BRAIN METASTASES

Journal article Neuro-Oncology · November 1, 2014 Full text Cite

Investigation of sagittal image acquisition for 4D-MRI with body area as respiratory surrogate.

Journal article Med Phys · October 2014 PURPOSE: The authors have recently developed a novel 4D-MRI technique for imaging organ respiratory motion employing cine acquisition in the axial plane and using body area (BA) as a respiratory surrogate. A potential disadvantage associated with axial ima ... Full text Link to item Cite

On the feasibility of polyurethane based 3D dosimeters with optical CT for dosimetric verification of low energy photon brachytherapy seeds.

Journal article Med Phys · July 2014 PURPOSE: To investigate the feasibility of and challenges yet to be addressed to measure dose from low energy (effective energy <50 keV) brachytherapy sources (Pd-103, Cs-131, and I-125) using polyurethane based 3D dosimeters with optical CT. METHODS: The ... Full text Link to item Cite

Review of treatment assessment using DCE-MRI in breast cancer radiation therapy.

Journal article World J Methodol · June 26, 2014 As a noninvasive functional imaging technique, dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is being used in oncology to measure properties of tumor microvascular structure and permeability. Studies have shown that parameters derived from ... Full text Link to item Cite

Stereotactic body radiotherapy: a critical review for nonradiation oncologists.

Journal article Cancer · April 1, 2014 Stereotactic body radiotherapy (SBRT) involves the treatment of extracranial primary tumors or metastases with a few, high doses of ionizing radiation. In SBRT, tumor kill is maximized and dose to surrounding tissue is minimized, by precise and accurate de ... Full text Link to item Cite

Four-dimensional magnetic resonance imaging using axial body area as respiratory surrogate: initial patient results.

Journal article Int J Radiat Oncol Biol Phys · March 15, 2014 PURPOSE: To evaluate the feasibility of a retrospective binning technique for 4-dimensional magnetic resonance imaging (4D-MRI) using body area (BA) as a respiratory surrogate. METHODS AND MATERIALS: Seven patients with hepatocellular carcinoma (4 of 7) or ... Full text Link to item Cite

Incorporating single-side sparing in models for predicting parotid dose sparing in head and neck IMRT.

Journal article Med Phys · February 2014 PURPOSE: Sparing of single-side parotid gland is a common practice in head-and-neck (HN) intensity modulated radiation therapy (IMRT) planning. It is a special case of dose sparing tradeoff between different organs-at-risk. The authors describe an improved ... Full text Link to item Cite

A limited-angle intrafraction verification (LIVE) system for radiation therapy.

Journal article Med Phys · February 2014 PURPOSE: Currently, no 3D or 4D volumetric x-ray imaging techniques are available for intrafraction verification of target position during actual treatment delivery or in-between treatment beams, which is critical for stereotactic radiosurgery (SRS) and st ... Full text Link to item Cite

Evaluating radiation-induced white matter changes in patients treated with stereotactic radiosurgery using diffusion tensor imaging: a pilot study.

Journal article Technol Cancer Res Treat · February 2014 Stereotactic radiosurgery (SRS) has been an effective treatment method for brain tumors; however, few data are available regarding radiation-induced white matter (WM) damage by SRS. In this work, diffusion tensor imaging (DTI) was used to investigate WM ch ... Full text Link to item Cite

Dynamic electron arc radiotherapy (DEAR): a feasibility study.

Journal article Phys Med Biol · January 20, 2014 Compared to other radiation therapy modalities, clinical electron beam therapy has remained practically unchanged for the past few decades even though electron beams with multiple energies are widely available on most linacs. In this paper, we present the ... Full text Link to item Cite

Onboard functional and molecular imaging: a design investigation for robotic multipinhole SPECT.

Journal article Med Phys · January 2014 PURPOSE: Onboard imaging-currently performed primarily by x-ray transmission modalities-is essential in modern radiation therapy. As radiation therapy moves toward personalized medicine, molecular imaging, which views individual gene expression, may also b ... Full text Link to item Cite

Dosimetric effects of rotational offsets in stereotactic body radiation therapy (SBRT) for lung cancer.

Journal article Med Dosim · 2014 To quantitatively evaluate dosimetric effects of rotational offsets in stereotactic body radiation therapy (SBRT) for lung cancer. Overall, 11 lung SBRT patients (8 female and 3 male; mean age: 75.0 years) with medially located tumors were included. Treatm ... Full text Link to item Cite

Dosimetric comparison of 3D conformal, IMRT, and V-MAT techniques for accelerated partial-breast irradiation (APBI).

Journal article Med Dosim · 2014 The purpose is to dosimetrically compare the following 3 delivery techniques: 3-dimensional conformal radiation therapy (3D-CRT), intensity-modulated arc therapy (IMRT), and volumetric-modulated arc therapy (V-MAT) in the treatment of accelerated partial-b ... Full text Link to item Cite

Stereotactic ablative body radiotherapy (SABR) for effective palliation of metastases: factors affecting local control.

Journal article J Radiosurg SBRT · 2014 We analyzed factors associated with inferior local control following stereotactic ablative body radiotherapy (SABR) for palliation of metastases. We reviewed records of patients receiving SABR for metastases at Duke University from 2006-2010. Biologically ... Link to item Cite

RTOG 0631 phase 2/3 study of image guided stereotactic radiosurgery for localized (1-3) spine metastases: phase 2 results.

Journal article Pract Radiat Oncol · 2014 Featured Publication PURPOSE: The phase 2 component of Radiation Therapy Oncology Group (RTOG) 0631 assessed the feasibility and safety of spine radiosurgery (SRS) for localized spine metastases in a cooperative group setting. METHODS AND MATERIALS: Patients with 1-3 spine met ... Full text Link to item Cite

Uncertainties of 4-dimensional computed tomography-based tumor motion measurement for lung stereotactic body radiation therapy.

Journal article Pract Radiat Oncol · 2014 Featured Publication PURPOSE: To evaluate how well tumor motion measured prior to treatment based on 4-dimensional computer tomography (4DCT) reflects actual tumor motion during beam-on throughout the course of treatment. METHODS AND MATERIALS: Twenty-three patients who had lu ... Full text Link to item Cite

A technique for estimating 4D-CBCT using prior knowledge and limited-angle projections.

Journal article Med Phys · December 2013 PURPOSE: To develop a technique to estimate onboard 4D-CBCT using prior information and limited-angle projections for potential 4D target verification of lung radiotherapy. METHODS: Each phase of onboard 4D-CBCT is considered as a deformation from one sele ... Full text Link to item Cite

Modeling the dosimetry of organ-at-risk in head and neck IMRT planning: an intertechnique and interinstitutional study.

Journal article Med Phys · December 2013 PURPOSE: To build a statistical model to quantitatively correlate the anatomic features of structures and the corresponding dose-volume histogram (DVH) of head and neck (HN) Tomotherapy (Tomo) plans. To study if the model built upon one intensity modulated ... Full text Link to item Cite

A line-source method for aligning on-board and other pinhole SPECT systems.

Journal article Med Phys · December 2013 PURPOSE: In order to achieve functional and molecular imaging as patients are in position for radiation therapy, a robotic multipinhole SPECT system is being developed. Alignment of the SPECT system-to the linear accelerator (LINAC) coordinate frame and to ... Full text Link to item Cite

Generation of virtual monochromatic CBCT from dual kV∕MV beam projections.

Journal article Med Phys · December 2013 PURPOSE: To develop a novel on-board imaging technique which allows generation of virtual monochromatic (VM) cone-beam CT (CBCT) with a selected energy from combined kilovoltage (kV)∕megavoltage (MV) beam projections. METHODS: With the current orthogonal k ... Full text Link to item Cite

Strategies for automatic online treatment plan reoptimization using clinical treatment planning system: a planning parameters study.

Journal article Med Phys · November 2013 PURPOSE: Adaptive radiation therapy for prostate cancer using online reoptimization provides an improved control of interfractional anatomy variations. However, the clinical implementation of online reoptimization is currently limited by the low efficiency ... Full text Link to item Cite

Evaluation of the effect of respiratory and anatomical variables on a Fourier technique for markerless, self-sorted 4D-CBCT.

Journal article Phys Med Biol · October 21, 2013 A novel technique based on Fourier transform theory has been developed that directly extracts respiratory information from projections without the use of external surrogates. While the feasibility has been demonstrated with three patients, a more extensive ... Full text Link to item Cite

A novel technique for VMAT QA with EPID in cine mode on a Varian TrueBeam linac.

Journal article Phys Med Biol · October 7, 2013 Volumetric modulated arc therapy (VMAT) is a relatively new treatment modality for dynamic photon radiation therapy. Pre-treatment quality assurance (QA) is necessary and many efforts have been made to apply electronic portal imaging device (EPID)-based IM ... Full text Link to item Cite

Single institution's dosimetry and IGRT analysis of prostate SBRT.

Journal article Radiat Oncol · September 13, 2013 BACKGROUND AND PURPOSE: To report single institution's IGRT and dosimetry analysis on the 37 Gy/5 fraction prostate SBRT clinical trial. MATERIALS/METHODS: The IRB (Duke University Medical Center) approved clinical trial has treated 28 patients with stage ... Full text Link to item Cite

A knowledge-based approach to improving and homogenizing intensity modulated radiation therapy planning quality among treatment centers: an example application to prostate cancer planning.

Journal article Int J Radiat Oncol Biol Phys · September 1, 2013 Featured Publication PURPOSE: Intensity modulated radiation therapy (IMRT) treatment planning can have wide variation among different treatment centers. We propose a system to leverage the IMRT planning experience of larger institutions to automatically create high-quality pla ... Full text Link to item Cite

Adaptive stereotactic body radiation therapy planning for lung cancer.

Journal article Int J Radiat Oncol Biol Phys · September 1, 2013 Featured Publication PURPOSE: To investigate the dosimetric effects of adaptive planning on lung stereotactic body radiation therapy (SBRT). METHODS AND MATERIALS: Forty of 66 consecutive lung SBRT patients were selected for a retrospective adaptive planning study. CBCT images ... Full text Link to item Cite

In reply to Kumar et al.

Journal article Int J Radiat Oncol Biol Phys · September 1, 2013 Full text Link to item Cite

Radiotherapy and radiosurgery for tumors of the central nervous system.

Journal article Surg Oncol Clin N Am · July 2013 Featured Publication In this article, the application of radiotherapy, alone and in combination with surgery and chemotherapy, in the treatment of metastases to the brain (the most common malignant brain lesion), primary malignant gliomas (the most common malignant primary bra ... Full text Link to item Cite

Respiration-phase-matched digital tomosynthesis imaging for moving target verification: a feasibility study.

Journal article Med Phys · July 2013 PURPOSE: To develop a respiration-phase-matched digital tomosynthesis (DTS) technique to monitor moving targets, and to evaluate its accuracy for various imaging parameters and anatomical characteristics. METHODS: Previously developed 3D-DTS techniques, re ... Full text Link to item Cite

SU-E-T-143: Dosimetric Characteristics of TrueBeam STx System with High Definition Multi-Leaf Collimator: Commissioning of Stereotactic Radiosurgery.

Journal article Med Phys · June 2013 IntroductionDosimetric characteristics of one TrueBeam STx treatment unit with a 120-leaf high definition multileaf collimator (HD120MLC) are systematically measured for commissioning of stereotactic radiosurgery (SRS). Due to limited data available, it is ... Full text Link to item Cite

TU-G-134-01: 4D-MRI Using Body Area as Internal Respiratory Surrogate: Initial Patient Results.

Journal article Med Phys · June 2013 PURPOSE: We have previously developed a novel 4D-MRI technique using body area (BA) as internal respiratory surrogate. This study is to demonstrate our initial patient results via validating the accuracy of tumor motion measurements and the improvement of ... Full text Link to item Cite

TH-C-141-07: T2-Weighted 4D-MRI with Combined Phase and Amplitude Sorting.

Journal article Med Phys · June 2013 PURPOSE: T2-weighted MR provides excellent delineation of malignant liver lesions due to its superior tumor-to-tissue contrast. This study aims to develop a novel T2-weighted retrospective 4D-MRI technique for imaging organ/tumor respiratory motion with im ... Full text Link to item Cite

WE-C-116-07: Tumor Enhancement Using Deformable Image Registration for Four-Dimensional Magnetic Resonance Imaging (4D-MRI): A Feasibility Study.

Journal article Med Phys · June 2013 PURPOSE: We have previously developed a 4D-MRI technique using the fast imaging sequence employing steady-state acquisition (FIESTA) sequence, which has suboptimal tumor-to-tissue contrast-to-noise ratio (CNR) due to its T2*/T1 weighting. This study invest ... Full text Link to item Cite

WE-G-134-04: Four-Dimensional Dual Cone-Beam CT (4D-DCBCT): Preliminary Experimental Results.

Journal article Med Phys · June 2013 PURPOSE: One of the major challenges for clinical implementation of 4D-CBCT is long scan time. This study aims to develop a 4D-DCBCT technique to improve the efficiency of 4D imaging (for motion management in radiation therapy). METHODS: A bench-top DCBCT ... Full text Link to item Cite

WE-A-500-01: Quality Control of Lung SBRT: Minimizing Uncertainties From Simulation to Treatment.

Journal article Med Phys · June 2013 Stringent quality control is critical to the success of lung SBRT. However, uncertainties exist in each step of the lung SBRT procedure. Characterization of organ motion using 4DCT may not present true tumor motion excursion due to its low temporal resolut ... Full text Link to item Cite

TH-C-137-11: Dose-Guided Automatic IMRT Planning: A Feasibility Study.

Journal article Med Phys · June 2013 PURPOSE: To develop and evaluate an automatic planning technique for prostate cancer utilizing prior expert plan's dose as guidance. METHODS: A plan atlas was created using 10 expert prostate IMRT plans covering a variety of typical anatomical configuratio ... Full text Link to item Cite

SU-D-500-06: On-Board Robotic Multi-Pinhole SPECT System for Prone Breast Imaging.

Journal article Med Phys · June 2013 PURPOSE: To investigate a novel Single Photon Emission Computed Tomography (SPECT) system for on-board molecular and functional imaging in partial breast radiation therapy of prone patients. METHODS: Computer-simulation studies were performed for on-board ... Full text Link to item Cite

Spiral computed tomography phase-space source model in the BEAMnrc/EGSnrc Monte Carlo system: implementation and validation.

Journal article Phys Med Biol · April 21, 2013 Featured Publication Currently, the BEAMnrc/EGSnrc Monte Carlo (MC) system does not provide a spiral CT source model for the simulation of spiral CT scanning. We developed and validated a spiral CT phase-space source model in the BEAMnrc/EGSnrc system. The spiral phase-space s ... Full text Link to item Cite

Quality requirements for stereotactic body radiation therapy (SBRT) in multi-institutional clinical trials

Journal article Ifmbe Proceedings · April 16, 2013 Featured Publication Clinical evidence have shown SBRT to be a tolerable, efficacious, and promising non-invasive therapy. Randomized prospective studies comparing surgery vs. SBRT in early-stage lung cancer are proposed to further investigate the relative survival, quality of ... Full text Cite

Quantification and minimization of uncertainties of internal target volume for stereotactic body radiation therapy of lung cancer.

Journal article Int J Radiat Oncol Biol Phys · February 1, 2013 Featured Publication PURPOSE: To quantify uncertainties in delineating an internal target volume (ITV) and to understand how these uncertainties may be individually minimized for stereotactic body radiation therapy (SBRT) of early stage non-small cell lung cancer (NSCLC). METH ... Full text Link to item Cite

A dual cone-beam CT system for image guided radiotherapy: initial performance characterization.

Journal article Med Phys · February 2013 Featured Publication PURPOSE: The purpose of this study is to evaluate the performance of a recently developed benchtop dual cone-beam computed tomography (CBCT) system with two orthogonally placed tube∕detector sets. METHODS: The benchtop dual CBCT system consists of two orth ... Full text Link to item Cite

Investigation of sliced body volume (SBV) as respiratory surrogate.

Journal article J Appl Clin Med Phys · January 7, 2013 Featured Publication The purpose of this study was to evaluate the sliced body volume (SBV) as a respiratory surrogate by comparing with the real-time position management (RPM) in phantom and patient cases. Using the SBV surrogate, breathing signals were extracted from unsorte ... Full text Open Access Link to item Cite

Improving Tumor-to-Tissue CNR of 4D-MRI Using Deformable Image Registration.

Journal article Pract Radiat Oncol · 2013 Full text Link to item Cite

Implementation of remote 3-dimensional image guided radiation therapy quality assurance for radiation therapy oncology group clinical trials.

Journal article Int J Radiat Oncol Biol Phys · January 1, 2013 Featured Publication PURPOSE: To report the process and initial experience of remote credentialing of three-dimensional (3D) image guided radiation therapy (IGRT) as part of the quality assurance (QA) of submitted data for Radiation Therapy Oncology Group (RTOG) clinical trial ... Full text Link to item Cite

Investigation of sliced body volume (SBV) as respiratory surrogate

Journal article Journal of Applied Clinical Medical Physics · January 1, 2013 Featured Publication The purpose of this study was to evaluate the sliced body volume (SBV) as a respiratory surrogate by comparing with the real-time position management (RPM) in phantom and patient cases. Using the SBV surrogate, breathing signals were extracted from unsorte ... Full text Cite

Implementing and integrating a clinically driven electronic medical record for radiation oncology in a large medical enterprise.

Journal article Front Oncol · 2013 PURPOSE/OBJECTIVE: While our department is heavily invested in computer-based treatment planning, we historically relied on paper-based charts for management of Radiation Oncology patients. In early 2009, we initiated the process of conversion to an electr ... Full text Link to item Cite

Interleaved acquisition for cross scatter avoidance in dual cone-beam CT.

Journal article Med Phys · December 2012 Featured Publication PURPOSE: Cone-beam x-ray imaging with flat panel detectors is used for target localization in image guided radiation therapy. This imaging includes cone-beam computed tomography (CBCT) and planar imaging. Use of two orthogonal x-ray systems could reduce im ... Full text Link to item Cite

Commissioning and dosimetric characteristics of TrueBeam system: composite data of three TrueBeam machines.

Journal article Med Phys · November 2012 Featured Publication PURPOSE: A TrueBeam linear accelerator (TB-LINAC) is designed to deliver traditionally flattened and flattening-filter-free (FFF) beams. Although it has been widely adopted in many clinics for patient treatment, limited information is available related to ... Full text Link to item Cite

Quantitative analysis of the factors which affect the interpatient organ-at-risk dose sparing variation in IMRT plans.

Journal article Med Phys · November 2012 Featured Publication PURPOSE: The authors present an evidence-based approach to quantify the effects of an array of patient anatomical features of the planning target volumes (PTVs) and organs-at-risk (OARs) and their spatial relationships on the interpatient OAR dose sparing ... Full text Link to item Cite

Stereotactic body radiotherapy treatment of extracranial metastases.

Journal article Nat Rev Clin Oncol · November 2012 Featured Publication Radiotherapy is an integral treatment for patients with metastatic cancer, although it is usually reserved for palliation of pain, dyspnoea, oedema, bleeding and neurological symptoms. However, the administration of high-precision radiotherapy, termed ster ... Full text Link to item Cite

Reproducibility of tumor motion probability distribution function in stereotactic body radiation therapy of lung cancer.

Journal article Int J Radiat Oncol Biol Phys · November 1, 2012 Featured Publication PURPOSE: To evaluate the reproducibility of tumor motion probability distribution function (PDF) in stereotactic body radiation therapy (SBRT) of lung cancer using cine megavoltage (MV) images. METHODS AND MATERIALS: Cine MV images of 20 patients acquired ... Full text Link to item Cite

Implementation of dual-energy technique for virtual monochromatic and linearly mixed CBCTs.

Journal article Med Phys · October 2012 Featured Publication PURPOSE: To implement dual-energy imaging technique for virtual monochromatic (VM) and linearly mixed (LM) cone beam CTs (CBCTs) and to demonstrate their potential applications in metal artifact reduction and contrast enhancement in image-guided radiation ... Full text Link to item Cite

Feasibility study of a synchronized-moving-grid (SMOG) system to improve image quality in cone-beam computed tomography (CBCT).

Journal article Med Phys · August 2012 Featured Publication PURPOSE: To evaluate the feasibility of a synchronized moving grid (SMOG) system to remove scatter artifacts, improve the contrast-to-noise ratio (CNR), and reduce image lag artifacts in cone-beam CT (CBCT). METHODS: The SMOG system proposed here uses a ra ... Full text Link to item Cite

Imaging system QA of a medical accelerator, Novalis Tx, for IGRT per TG 142: our 1 year experience.

Journal article J Appl Clin Med Phys · July 5, 2012 Featured Publication American Association of Physicists in Medicine (AAPM) task group (TG) 142 has recently published a report to update recommendations of the AAPM TG 40 report and add new recommendations concerning medical accelerators in the era of image-guided radiation th ... Full text Open Access Link to item Cite

SU-E-J-209: A Simple Method to Minimize Uncertainty in ITV Delineation: Phantom Verification.

Journal article Med Phys · June 2012 PURPOSE: Irregular breathing causes variation in delineation of internal target volume (ITV), which is typically generated in the maximum intensity projection (MIP) images [1]. Previous studies have shown that MIP-based ITV can underestimate true tumor ran ... Full text Link to item Cite

SU-E-J-145: Implementing 4D XCAT Phantom for 4D Radiotherapy Research.

Journal article Med Phys · June 2012 PURPOSE: To characterize and implement the 4D Integrated Extended Cardiac Torso (XCAT) digital phantom for 4D radiotherapy (RT) application. METHODS: A computer program was developed to facilitate the characterization and implementation of the 4D XCAT phan ... Full text Link to item Cite

TU-E-BRB-04: Adaptive Stereotactic-Body Radiation Therapy (SBRT) Planning for Lung Cancer.

Journal article Med Phys · June 2012 PURPOSE: Tumor shrinkage during lung SBRT has been reported. Adaptive SBRT planning can potentially escalate dose to the target and mitigate dose to surrounding tissues. In this study, we investigated dosimetric effects of adaptive lung SBRT planning using ... Full text Link to item Cite

MO-A-213AB-04: Verification of 4D Dose Delivery Using 4D Digital Human Phantom.

Journal article Med Phys · June 2012 PURPOSE: At present, techniques of 4D dose verification in radiation therapy for lung cancers associated with respiratory motion are very limited, due to either lack of patient anatomy or breathing information. The aim of this study is to develop a 4D dose ... Full text Link to item Cite

SU-D-218-02: 4D-MRI Based on Body Area (BA) Surrogate and Sagittal Image Acquisition.

Journal article Med Phys · June 2012 PURPOSE: 4D-MRI based on body area (BA) surrogate using axial image acquisition has been demonstrated. Since respiratory motion mostly occurs in the superior-inferior (SI) direction, it is expected that sagittal acquisition may provide more robust and accu ... Full text Link to item Cite

SU-E-J-32: Evaluation of the Dosimetric Accuracy of Stereotactic Radiosurgery with Cone-Beam Computed Tomography Localization.

Journal article Med Phys · June 2012 PURPOSE: To evaluate the dosimetric accuracy of stereotactic radiosurgery (SRS) with cone-beam computed tomography (CBCT) guided patient localization. METHODS: A Novalis TX linear accelerator with high definition multileaf collimator (HDMLC) was used for S ... Full text Link to item Cite

SU-E-T-104: Commissioning and Dosimetric Characteristics of TrueBeam System: Composite Data of Three TrueBeam Machines.

Journal article Med Phys · June 2012 INTRODUCTION: A TrueBeam linear accelerator (TB-LINAC) is designed to deliver standard flattened and flattening-filter-free (FFF) beams. In our institute, three TB-LINAC units are installed. In this work, composite data of the three units and multi-unit co ... Full text Link to item Cite

MO-D-BRB-09: Treatment Delivery QA for Online Adaptive Radiation Therapy Based on Dynamic Machine Information (DMI): A Feasibility Study.

Journal article Med Phys · June 2012 PURPOSE: To implement a quality assurance (QA) system for the treatment delivery of online adaptive radiation therapy utilizing Dynamic Machine Information (DMI). MATERIALS AND METHODS: DMI provides the expected/actual MLC leaf-positions, delivered MU, and ... Full text Link to item Cite

SU-E-T-559: Evaluation of Flatening Filter Free (FFF) Beams in Radiotherapy of Head and Neck Cancer.

Journal article Med Phys · June 2012 PURPOSE: To investigate th applicability of the flattening filter free (FFF) to fractionated radiotherapy of head and neck cancer. METHODS: Twelve patients previously treated with IMRT were selected. A SIB protocol was chosen so that 66/54 Gy were prescrib ... Full text Link to item Cite

Stereotactic radiotherapy for malignancies involving the trigeminal and facial nerves.

Journal article Technol Cancer Res Treat · June 2012 Featured Publication Involvement of a cranial nerve caries a poor prognosis for many malignancies. Recurrent or residual disease in the trigeminal or facial nerve after primary therapy poses a challenge due to the location of the nerve in the skull base, the proximity to the b ... Full text Link to item Cite

Target localization using scanner-acquired SPECT data.

Journal article J Appl Clin Med Phys · May 10, 2012 Featured Publication Target localization using single photon emission computed tomography (SPECT) and planar imaging is being investigated for guiding radiation therapy delivery. Previous studies on SPECT-based localization have used computer-simulated or hybrid images with si ... Full text Open Access Link to item Cite

Dosimetric comparison of treatment plans based on free breathing, maximum, and average intensity projection CTs for lung cancer SBRT.

Journal article Med Phys · May 2012 Featured Publication PURPOSE: To determine whether there is a CT dataset may be more favorable for planning and dose calculation by comparing dosimetric characteristics between treatment plans calculated using free breathing (FB), maximum and average intensity projection (MIP ... Full text Link to item Cite

Comparison of 3D conformal breast radiation treatment plans using the anisotropic analytical algorithm and pencil beam convolution algorithm.

Journal article Radiother Oncol · May 2012 Featured Publication PURPOSE: To investigate (1) dosimetric differences between plans calculated using the anisotropic analytical algorithm (AAA) and pencil beam convolution (PBC) algorithm, (2) the plan quality achieved using AAA compared to PBC based on dosimetric parameters ... Full text Link to item Cite

Volumetric-modulated arc therapy: effective and efficient end-to-end patient-specific quality assurance.

Journal article Int J Radiat Oncol Biol Phys · April 1, 2012 Featured Publication PURPOSE: To explore an effective and efficient end-to-end patient-specific quality-assurance (QA) protocol for volumetric modulated arc radiotherapy (VMAT) and to evaluate the suitability of a stationary radiotherapy QA device (two-dimensional [2D] ion cha ... Full text Link to item Cite

Development and clinical evaluation of a three-dimensional cone-beam computed tomography estimation method using a deformation field map.

Journal article Int J Radiat Oncol Biol Phys · April 1, 2012 Featured Publication PURPOSE: To develop a three-dimensional (3D) cone-beam computed tomography (CBCT) estimation method using a deformation field map, and to evaluate and optimize the efficiency and accuracy of the method for use in the clinical setting. METHODS AND MATERIALS ... Full text Link to item Cite

Accelerating phase contrast MR angiography by simplified skipped phase encoding and edge deghosting with array coil enhancement.

Journal article Med Phys · March 2012 Featured Publication PURPOSE: The aim of this work is to investigate the feasibility of accelerating phase contrast magnetic resonance angiography (PC-MRA) by the fast imaging method of simplified skipped phase encoding and edge deghosting with array coil enhancement (S-SPEED- ... Full text Link to item Cite

A novel technique for markerless, self-sorted 4D-CBCT: feasibility study.

Journal article Med Phys · March 2012 Featured Publication PURPOSE: Four-dimensional CBCT (4D-CBCT) imaging in the treatment room can provide verification of moving targets, facilitating the potential for margin reduction and consequent dose escalation. Reconstruction of 4D-CBCT images requires correlation of resp ... Full text Link to item Cite

Lipiodol: a potential direct surrogate for cone-beam computed tomography image guidance in radiotherapy of liver tumor.

Journal article Int J Radiat Oncol Biol Phys · February 1, 2012 Featured Publication PURPOSE: To investigate the feasibility of using lipiodol as a direct surrogate for target localization using cone-beam CT (CBCT) image guidance in radiotherapy (RT) of patients with unresectable liver tumors after transarterial chemoembolization. METHODS ... Full text Link to item Cite

DOSE DEPENDENCE OF RADIATION-INDUCED ERECTILE DYSFUNCTION IN AN ANIMAL MODEL

Journal article JOURNAL OF SEXUAL MEDICINE · February 1, 2012 Link to item Cite

Imaging system QA of a medical accelerator, Novalis Tx, for IGRT per TG 142: Our 1 year experience

Journal article Journal of Applied Clinical Medical Physics · January 1, 2012 Featured Publication American Association of Physicists in Medicine (AAPM) task group (TG) 142 has recently published a report to update recommendations of the AAPM TG 40 report and add new recommendations concerning medical accelerators in the era of image-guided radiation th ... Full text Cite

Target localization using scanner-acquired SPECT data

Journal article Journal of Applied Clinical Medical Physics · January 1, 2012 Featured Publication Target localization using single photon emission computed tomography (SPECT) and planar imaging is being investigated for guiding radiation therapy delivery. Previous studies on SPECT-based localization have used computer-simulated or hybrid images with si ... Full text Cite

Development of a 4D dosimetry simulation system in radiotherapy

Journal article International Journal of Biomedical Engineering and Technology · January 1, 2012 Featured Publication 4D CT image sets are used to encode patient-organ motion and to calculate the dose delivered during each respiratory phase. The dose-per-phase is summarised to the total dose via deformable registration. The system incorporates the actual beam parameters a ... Full text Cite

Establishing a framework to implement 4D XCAT phantom for 4D radiotherapy research.

Journal article J Cancer Res Ther · 2012 Featured Publication AIMS: To establish a framework to implement the 4D integrated extended cardiac torso (XCAT) digital phantom for 4D radiotherapy (RT) research. MATERIALS AND METHODS: A computer program was developed to facilitate the characterization and implementation of ... Full text Link to item Cite

Four-dimensional magnetic resonance imaging (4D-MRI) using image-based respiratory surrogate: a feasibility study.

Journal article Med Phys · December 2011 Featured Publication PURPOSE: Four-dimensional computed tomography (4D-CT) has been widely used in radiation therapy to assess patient-specific breathing motion for determining individual safety margins. However, it has two major drawbacks: low soft-tissue contrast and an exce ... Full text Link to item Cite

RTOG 0631 Phase II/III Study of Image-Guided Stereotactic Radiosurgery for Localized (1-3) Spine Metastases: Phase II Results.

Journal article Int J Radiat Oncol Biol Phys · October 1, 2011 PURPOSE: The phase II component of RTOG 0631 assessed the feasibility and safety of spine radiosurgery (SRS) for localized spine metastases in a cooperative group setting. MATERIALS AND METHODS: Patients with 1-3 spine metastasis with a Numerical Rating Pa ... Full text Link to item Cite

RTOG 0631 Phase II/III Study of Image-guided Stereotactic Radiosurgery for Localized Spine Metastases: Phase II Results

Journal article International Journal of Radiation Oncology*Biology*Physics · October 2011 Full text Cite

Contour based respiratory motion analysis for free breathing CT.

Journal article Comput Biol Med · October 2011 Featured Publication We propose a method to quantify superior-inferior (SI) motion of a rigid target using the 3D contour from free-breathing CT (FBCT). The technique utilizes similarity between 2D contours (Jaccard Index) and a population based density function for probabilit ... Full text Link to item Cite

Fourier Transform (FT) Techniques for Markerless 4D Cone-beam CT (4D-CBCT) Sorting: Comparison between Phase vs. Magnitude

Journal article International Journal of Radiation Oncology*Biology*Physics · October 2011 Full text Cite

Correlation between External Surrogate Motion and Lung Tumor Motion: From a Statistical Point of View

Journal article International Journal of Radiation Oncology*Biology*Physics · October 2011 Full text Cite

A Dual-Isocenter Technique for Image Guidance of Prone-Breast Radiation Therapy

Journal article International Journal of Radiation Oncology*Biology*Physics · October 2011 Full text Cite

Radiation-induced erectile dysfunction using prostate-confined modern radiotherapy in a rat model.

Journal article J Sex Med · August 2011 Featured Publication INTRODUCTION: The mechanisms of radiation-induced erectile dysfunction (ED) are unclear, as clinical studies are limited, and previous animal models were based on wide-field irradiation, which does not model current radiotherapy (RT) techniques. AIMS: To p ... Full text Link to item Cite

Potential underestimation of the internal target volume (ITV) from free-breathing CBCT.

Journal article Med Phys · August 2011 Featured Publication PURPOSE: Localization prior to delivery of SBRT to free-breathing patients is performed by aligning the planning internal target volume (ITV) from 4DCT with an on-board free-breathing cone-beam CT (FB-CBCT) image. The FB-CBCT image is assumed to also gener ... Full text Link to item Cite

Evaluation of integrated respiratory gating systems on a Novalis Tx system.

Journal article J Appl Clin Med Phys · April 4, 2011 Featured Publication The purpose of this study was to investigate the accuracy of motion tracking and radiation delivery control of integrated gating systems on a Novalis Tx system. The study was performed on a Novalis Tx system, which is equipped with Varian Real-time Positio ... Full text Open Access Link to item Cite

Crescent artifacts in cone-beam CT.

Journal article Med Phys · April 2011 Featured Publication PURPOSE: In image-guided radiation therapy, cone-beam CT has been adopted for three-dimensional target localization in the treatment room. In many of these cone-beam CT images, dark and light crescent artifacts can be seen. This study investigates potentia ... Full text Link to item Cite

Adaptive prostate IGRT combining online re-optimization and re-positioning: a feasibility study.

Journal article Phys Med Biol · March 7, 2011 Featured Publication In prostate radiation therapy, inter-fractional organ motion/deformation has posed significant challenges on reliable daily dose delivery. To correct for this issue, off-line re-optimization and online re-positioning have been used clinically. In this pape ... Full text Link to item Cite

A planning quality evaluation tool for prostate adaptive IMRT based on machine learning.

Journal article Med Phys · February 2011 Featured Publication PURPOSE: To ensure plan quality for adaptive IMRT of the prostate, we developed a quantitative evaluation tool using a machine learning approach. This tool generates dose volume histograms (DVHs) of organs-at-risk (OARs) based on prior plans as a reference ... Full text Link to item Cite

Feasibility study of an intensity-modulated radiation model for the study of erectile dysfunction.

Journal article J Sex Med · February 2011 Featured Publication INTRODUCTION: Preclinical studies of radiotherapy (RT) induced erectile dysfunction (ED) have been limited by radiation toxicity when using large fields. AIM: To develop a protocol of rat prostate irradiation using techniques mimicking the current clinical ... Full text Link to item Cite

Computed tomography dose index and dose length product for cone-beam CT: Monte Carlo simulations.

Journal article J Appl Clin Med Phys · January 19, 2011 Featured Publication Dosimetry in kilovoltage cone beam computed tomography (CBCT) is a challenge due to the limitation of physical measurements. To address this, we used a Monte Carlo (MC) method to estimate the CT dose index (CTDI) and the dose length product (DLP) for a com ... Full text Open Access Link to item Cite

Evaluation of motion measurement using cine MRI for image guided stereotactic body radiotherapy on a new phantom platform.

Journal article J Radiosurg SBRT · 2011 The objective of this study is to investigate accuracy of motion tracking of cine magnetic resonance imaging (MRI) for image-guided stereotactic body radiotherapy. A phantom platform was developed in this work to fulfill the goal. The motion phantom consis ... Link to item Cite

Adaptive radiation therapy: technical components and clinical applications.

Journal article Cancer J · 2011 Featured Publication In current standard radiation therapy process, patient anatomy is represented by the snapshot of computed tomographic images at the simulation for treatment planning. However, patient anatomy during the treatment course is not static, and the changes can b ... Full text Link to item Cite

Dosimetric comparison of 6 MV and 15 MV single arc rapidarc to helical TomoTherapy for the treatment of pancreatic cancer.

Journal article Med Dosim · 2011 Featured Publication We conducted a planning study to compare Varian's RapidArc (RA) and helical TomoTherapy (HT) for the treatment of pancreatic cancer. Three intensity-modulated radiotherapy (IMRT) plans were generated for 8 patients with pancreatic cancer: one using HT with ... Full text Link to item Cite

Digital tomosynthesis for respiratory gated liver treatment: clinical feasibility for daily image guidance.

Journal article Int J Radiat Oncol Biol Phys · January 1, 2011 Featured Publication PURPOSE: Breath-hold (BH) treatment minimizes internal target volumes (ITV) when treating sites prone to motion. Digital tomosynthesis (DTS) imaging has advantages over cone-beam CT (CBCT) for BH imaging: BH-DTS scan can be completed during a single breath ... Full text Link to item Cite

Evaluation of integrated respiratory gating systems on a Novalis Tx system

Journal article Journal of Applied Clinical Medical Physics · January 1, 2011 Featured Publication The purpose of this study was to investigate the accuracy of motion tracking and radiation delivery control of integrated gating systems on a Novalis Tx system. The study was performed on a Novalis Tx system, which is equipped with Varian Real-time Positio ... Full text Cite

Computed tomography dose index and dose length product for cone-beam CT: Monte Carlo simulations of a commercial system

Journal article Journal of Applied Clinical Medical Physics · January 1, 2011 Featured Publication Dosimetry in kilovoltage cone beam computed tomography (CBCT) is a challenge due to the limitation of physical measurements. To address this, we used a Monte Carlo (MC) method to estimate the CT dose index (CTDI) and the dose length product (DLP) for a com ... Full text Cite

Response to comment on: A planning quality evaluation tool for prostate adaptive IMRT based on machine learning' Med. Phys. 38, 719 (2011)

Journal article Medical Physics · January 1, 2011 Featured Publication Full text Cite

Apparatus-dependent dosimetric differences in spine stereotactic body radiotherapy.

Journal article Technol Cancer Res Treat · December 2010 Featured Publication The purpose of this investigation was to study apparatus-dependent dose distribution differences specific to spine stereotactic body radiotherapy (SBRT) treatment planning. This multi-institutional study was performed evaluating an image-guided robotic rad ... Full text Link to item Cite

Regional SPECT imaging using sampling principles and multiple pinholes

Journal article IEEE Nuclear Science Symposium Conference Record · December 1, 2010 Featured Publication There may be many SPECT imaging applications in which a small region is primarily of interest. One such case is imaging in the radiation therapy treatment room, as the patient is on the treatment table in position for radiation therapy. This onboard imagin ... Full text Cite

Maximum intensity projection (MIP) imaging using slice-stacking MRIa).

Journal article Med Phys · November 2010 Featured Publication PURPOSE: To evaluate the feasibility of acquiring maximum intensity projection (MIP) images using a novel slice-stacking MRI (SS-MRI) technique. METHODS: The proposed technique employed a steady state acquisition sequence to image multiple axial slices. At ... Full text Link to item Cite

Impact of volumetric modulated arc therapy technique on treatment with partial breast irradiation.

Journal article Int J Radiat Oncol Biol Phys · September 1, 2010 Featured Publication PURPOSE: To investigate the technical feasibility of volumetric modulated arc therapy (V-MAT) in the delivery of partial breast irradiation (PBI). METHODS AND MATERIALS: V-MAT and the standard, three-dimensional conformal radiotherapy (3D-CRT), were compar ... Full text Link to item Cite

Direction-dependent localization errors in SPECT images.

Journal article Med Phys · September 2010 Featured Publication PURPOSE: Single photon emission computed tomography (SPECT) is being investigated for imaging inside radiation therapy treatment rooms to localize biological targets. Here, computer simulations were used to analyze locational and directional dependencies i ... Full text Link to item Cite

Effects of breathing variation on gating window internal target volume in respiratory gated radiation therapya).

Journal article Med Phys · August 2010 Featured Publication PURPOSE: To investigate the effects of breathing variation on gating window internal target volume(ITVGW) in respiratory gated radiation therapy. METHOD AND MATERIALS: Two-dimensional dynamic MRI (dMRI) of lung motion was acquired in ten volunteers and eig ... Full text Link to item Cite

Stereotactic body radiation therapy: the report of AAPM Task Group 101.

Journal article Med Phys · August 2010 Featured Publication Task Group 101 of the AAPM has prepared this report for medical physicists, clinicians, and therapists in order to outline the best practice guidelines for the external-beam radiation therapy technique referred to as stereotactic body radiation therapy (SB ... Full text Link to item Cite

Arc-modulated radiation therapy based on linear models.

Journal article Phys Med Biol · July 7, 2010 Featured Publication This paper reports an inverse arc-modulated radiation therapy planning technique based on linear models. It is implemented with a two-step procedure. First, fluence maps for 36 fixed-gantry beams are generated using a linear model-based intensity-modulated ... Full text Link to item Cite

Kilovoltage cone-beam CT: comparative dose and image quality evaluations in partial and full-angle scan protocols.

Journal article Med Phys · July 2010 Featured Publication PURPOSE: To assess imaging dose of partial and full-angle kilovoltage CBCT scan protocols and to evaluate image quality for each protocol. METHODS: The authors obtained the CT dose index (CTDI) of the kilovoltage CBCT protocols in an on-board imager by ion ... Full text Link to item Cite

Increased nucleolar localization of SpiA3G in classically but not alternatively activated macrophages.

Journal article FEBS Lett · June 3, 2010 Macrophages play a key role in innate immune response to pathogens and in tissue homeostasis, inflammation and repair. A serpin A3G (SpiA3G) is highly induced in classically activated macrophages. We show increased localization of SpiA3G in the nucleolus a ... Full text Link to item Cite

Estimation of computed tomography dose index in cone beam computed tomography: MOSFET measurements and Monte Carlo simulations.

Journal article Health Phys · May 2010 Featured Publication To address the lack of accurate dose estimation method in cone beam computed tomography (CBCT), we performed point dose metal oxide semiconductor field-effect transistor (MOSFET) measurements and Monte Carlo (MC) simulations. A Varian On-Board Imager (OBI) ... Full text Link to item Cite

6D image guidance for spinal non-invasive stereotactic body radiation therapy: Comparison between ExacTrac X-ray 6D with kilo-voltage cone-beam CT.

Journal article Radiother Oncol · April 2010 Featured Publication PURPOSE: To investigate setup discrepancies measured with ExacTrac X-ray 6 degree-of-freedom (6D) and cone-beam computed tomography (CBCT) for patients under treatments of stereotactic body radiation therapy (SBRT). MATERIALS AND METHODS: In this work, pha ... Full text Link to item Cite

Radiotherapy treatment plans with RapidArc for prostate cancer involving seminal vesicles and lymph nodes.

Journal article Int J Radiat Oncol Biol Phys · March 1, 2010 Featured Publication PURPOSE: Dosimetric results and treatment delivery efficiency of RapidArc plans to those of conventional intensity-modulated radiotherapy (IMRT) plans were compared using the Eclipse treatment planning system for high-risk prostate cancer. MATERIALS AND ME ... Full text Link to item Cite

Estimation of absorbed doses from paediatric cone-beam CT scans: MOSFET measurements and Monte Carlo simulations.

Journal article Radiat Prot Dosimetry · March 2010 Featured Publication The purpose of this study was to establish a dose estimation tool with Monte Carlo (MC) simulations. A 5-y-old paediatric anthropomorphic phantom was computed tomography (CT) scanned to create a voxelised phantom and used as an input for the abdominal cone ... Full text Link to item Cite

Accelerating non-contrast-enhanced MR angiography with inflow inversion recovery imaging by skipped phase encoding and edge deghosting (SPEED).

Journal article J Magn Reson Imaging · March 2010 Featured Publication PURPOSE: To accelerate non-contrast-enhanced MR angiography (MRA) with inflow inversion recovery (IFIR) with a fast imaging method, Skipped Phase Encoding and Edge Deghosting (SPEED). MATERIALS AND METHODS: IFIR imaging uses a preparatory inversion pulse t ... Full text Link to item Cite

Point/counterpoint. The traditional L-shaped gantry for radiotherapy linear accelerators will soon become obsolete.

Journal article Med Phys · February 2010 Featured Publication Full text Link to item Cite

Slow gantry rotation acquisition technique for on-board four-dimensional digital tomosynthesis.

Journal article Med Phys · February 2010 Featured Publication PURPOSE: Four-dimensional cone-beam computed tomography (4D CBCT) has been investigated for motion imaging in the radiotherapy treatment room. The drawbacks of 4D CBCT are long scan times and high imaging doses. The aims of this study were to develop and i ... Full text Link to item Cite

A methodology for selecting the beam arrangement to reduce the intensity-modulated radiation therapy (IMRT) dose to the SPECT-defined functioning lung.

Journal article Phys Med Biol · January 21, 2010 Featured Publication Macroaggregated albumin single-photon emission computed tomography (MAA-SPECT) provides a map of the spatial distribution of lung perfusion. Our previous work developed a methodology to use SPECT guidance to reduce the dose to the functional lung in IMRT p ... Full text Link to item Cite

Similarities between static and rotational intensity-modulated plans.

Journal article Phys Med Biol · January 7, 2010 Featured Publication The aim of this study was to explore similarities between intensity-modulated radiotherapy (IMRT) and intensity-modulated arc therapy (IMAT) techniques in the context of the number of multi-leaf collimator (MLC) segments required to achieve plan objectives ... Full text Link to item Cite

SU-DD-A3-05: On-Board SPECT: Localization Study Using Scanner-Acquired Data

Journal article Medical Physics · 2010 Cite

Dosimetry challenges for implementing emerging technologies.

Journal article J Phys Conf Ser · 2010 Featured Publication During the last 10 years, radiation therapy technologies have gone through major changes, mainly related introduction of sophisticated delivery and imaging techniques to improve the target localization accuracy and dose conformity. While implementation of ... Full text Link to item Cite

Radiation dose from cone beam CT in a pediatric phantom: risk estimation of cancer incidence.

Journal article AJR Am J Roentgenol · January 2010 Featured Publication OBJECTIVE: The objective of our study was to measure absorbed doses and calculate effective dose (ED) from cone beam CT (CBCT) with metal oxide semiconductor field effect transistor (MOSFET) detectors in an anthropomorphic phantom and to estimate the risk ... Full text Link to item Cite

On-line adaptive radiation therapy: feasibility and clinical study.

Journal article J Oncol · 2010 Featured Publication The purpose of this paper is to evaluate the feasibility and clinical dosimetric benefit of an on-line, that is, with the patient in the treatment position, Adaptive Radiation Therapy (ART) system for prostate cancer treatment based on daily cone-beam CT i ... Full text Open Access Link to item Cite

Patient specific quality assurance: Transition from IMRT to IMAT

Journal article Journal of Physics Conference Series · January 1, 2010 Featured Publication The purpose of this study was to test a patient-specific quality assurance (QA) protocol for intensity-modulated arc radiotherapy (IMAT), and to evaluate the use of an intensity-modulated stationary radiotherapy QA device (2D ion chamber array). Thirty-nin ... Full text Cite

ExacTrac X-ray 6 degree-of-freedom image-guidance for intracranial non-invasive stereotactic radiotherapy: comparison with kilo-voltage cone-beam CT.

Journal article Radiother Oncol · December 2009 Featured Publication BACKGROUND AND PURPOSE: To compare the residual setup errors measured with ExacTrac X-ray 6 degree-of-freedom (6D) and cone-beam computed tomography (CBCT) for a head phantom and patients receiving intracranial non-invasive fractionated stereotactic radiot ... Full text Link to item Cite

Volumetric arc intensity-modulated therapy for spine body radiotherapy: comparison with static intensity-modulated treatment.

Journal article Int J Radiat Oncol Biol Phys · December 1, 2009 Featured Publication PURPOSE: This clinical study evaluates the feasibility of using volumetric arc-modulated treatment (VMAT) for spine stereotactic body radiotherapy (SBRT) to achieve highly conformal dose distributions that spare adjacent organs at risk (OAR) with reduced t ... Full text Link to item Cite

A positioning QA procedure for 2D/2D (kV/MV) and 3D/3D (CT/CBCT) image matching for radiotherapy patient setup.

Journal article J Appl Clin Med Phys · October 6, 2009 Featured Publication A positioning QA procedure for Varian's 2D/2D (kV/MV) and 3D/3D (planCT/CBCT) matching was developed. The procedure was to check: (1) the coincidence of on-board imager (OBI), portal imager (PI), and cone beam CT (CBCT)'s isocenters (digital graticules) to ... Full text Open Access Link to item Cite

Development of a neuro-fuzzy technique for automated parameter optimization of inverse treatment planning.

Journal article Radiat Oncol · September 25, 2009 Featured Publication BACKGROUND: Parameter optimization in the process of inverse treatment planning for intensity modulated radiation therapy (IMRT) is mainly conducted by human planners in order to create a plan with the desired dose distribution. To automate this tedious pr ... Full text Open Access Link to item Cite

Tradeoffs of integrating real-time tracking into IGRT for prostate cancer treatment.

Journal article Phys Med Biol · September 7, 2009 Featured Publication This study investigated the integration of the Calypso real-time tracking system, based on implanted ferromagnetic transponders and a detector array, into the current process for image-guided radiation treatment (IGRT) of prostate cancer at our institution ... Full text Link to item Cite

Task Group 142 report: quality assurance of medical accelerators.

Journal article Med Phys · September 2009 Featured Publication The task group (TG) for quality assurance of medical accelerators was constituted by the American Association of Physicists in Medicine's Science Council under the direction of the Radiation Therapy Committee and the Quality Assurance and Outcome Improveme ... Full text Link to item Cite

American Society of Radiation Oncology recommendations for documenting intensity-modulated radiation therapy treatments.

Journal article Int J Radiat Oncol Biol Phys · August 1, 2009 Featured Publication Despite the widespread use of intensity-modulated radiation therapy (IMRT) for approximately a decade, a lack of adequate guidelines for documenting these treatments persists. Proper IMRT treatment documentation is necessary for accurate reconstruction of ... Full text Link to item Cite

Advances in technology for intracranial stereotactic radiosurgery.

Journal article Technol Cancer Res Treat · August 2009 Featured Publication Stereotactic radiosurgery (SRS) refers to a single radiation treatment delivering a high dose to an intra-cranial target localized in three-dimensions by CT and/or MRI imaging. Traditionally, immobilization of the patient's head has been achieved using a r ... Full text Link to item Cite

Comparison of online IGRT techniques for prostate IMRT treatment: adaptive vs repositioning correction.

Journal article Med Phys · May 2009 Featured Publication This study compares three online image guidance techniques (IGRT) for prostate IMRT treatment: bony-anatomy matching, soft-tissue matching, and online replanning. Six prostate IMRT patients were studied. Five daily CBCT scans from the first week were acqui ... Full text Link to item Cite

On-board SPECT for localizing functional targets: a simulation study.

Journal article Med Phys · May 2009 Featured Publication Single photon emission computed tomography (SPECT) was investigated for imaging on-board radiation therapy machines in order to localize functional and molecular targets. A computer-simulated female NCAT phantom was positioned supine on a flat-top treatmen ... Full text Link to item Cite

Ice as a water-equivalent solid medium for brachytherapy dosimetric measurements.

Journal article Radiat Environ Biophys · April 2009 Featured Publication Precise positioning of source and dosimeters is essential in the experimental determination of dosimetric characteristics of brachytherapy sources. Various near-water equivalent solid phantoms have been used to achieve the necessary precision in the positi ... Full text Link to item Cite

Stereotactic body radiotherapy for lesions of the spine and paraspinal regions.

Journal article Int J Radiat Oncol Biol Phys · April 1, 2009 Featured Publication PURPOSE: To describe our experience and clinical strategy for stereotactic body radiotherapy (SBRT) of spinal lesions. METHODS AND MATERIALS: Thirty-two patients with 33 spinal lesions underwent computed tomography-based simulation while free breathing. Gr ... Full text Link to item Cite

Tracking brachytherapy sources using emission imaging with one flat panel detector.

Journal article Med Phys · April 2009 Featured Publication This work proposes to use the radiation from brachytherapy sources to track their dwell positions in three-dimensional (3D) space. The prototype device uses a single flat panel detector and a BB tray. The BBs are arranged in a defined pattern. The shadow o ... Full text Link to item Cite

Comparing digital tomosynthesis to cone-beam CT for position verification in patients undergoing partial breast irradiation.

Journal article Int J Radiat Oncol Biol Phys · March 1, 2009 Featured Publication PURPOSE: To evaluate digital tomosynthesis (DTS) technology for daily positioning of patients receiving accelerated partial breast irradiation (APBI) and to compare the positioning accuracy of DTS to three-dimensional cone-beam computed tomography (CBCT). ... Full text Link to item Cite

Refinement of treatment setup and target localization accuracy using three-dimensional cone-beam computed tomography for stereotactic body radiotherapy.

Journal article Int J Radiat Oncol Biol Phys · February 1, 2009 Featured Publication PURPOSES: To quantitatively compare two-dimensional (2D) orthogonal kV with three-dimensional (3D) cone-beam CT (CBCT) for target localization; and to assess intrafraction motion with kV images in patients undergoing stereotactic body radiotherapy (SBRT). ... Full text Link to item Cite

Impact of collimator leaf width and treatment technique on stereotactic radiosurgery and radiotherapy plans for intra- and extracranial lesions.

Journal article Radiat Oncol · January 21, 2009 Featured Publication BACKGROUND: This study evaluated the dosimetric impact of various treatment techniques as well as collimator leaf width (2.5 vs 5 mm) for three groups of tumors -- spine tumors, brain tumors abutting the brainstem, and liver tumors. These lesions often pre ... Full text Open Access Link to item Cite

Impact of collimator leaf width and treatment technique on stereotactic radiosurgery and radiotherapy plans for intra- and extracranial lesions

Journal article Radiation Oncology · January 21, 2009 Featured Publication Background: This study evaluated the dosimetric impact of various treatment techniques as well as collimator leaf width (2.5 vs 5 mm) for three groups of tumors - spine tumors, brain tumors abutting the brainstem, and liver tumors. These lesions often pres ... Full text Cite

Efficient multiple acquisitions by Skipped Phase Encoding and Edge Deghosting (SPEED) using shared spatial information.

Journal article Magn Reson Med · January 2009 Featured Publication The fast MRI method of Skipped Phase Encoding and Edge Deghosting (SPEED) is further developed to accelerate multiple acquisitions. In a single acquisition, SPEED first acquires three sparse ghosted edge maps with an undersampling factor of N/3, which are ... Full text Link to item Cite

Clinical evaluation of positioning verification using digital tomosynthesis and bony anatomy and soft tissues for prostate image-guided radiotherapy.

Journal article Int J Radiat Oncol Biol Phys · January 1, 2009 Featured Publication PURPOSE: To evaluate on-board digital tomosynthesis (DTS) for patient positioning vs. two-dimensional (2D) radiography and three-dimensional cone beam (CBCT). METHODS AND MATERIALS: A total of 92 image sessions from 9 prostate cancer patients were analyzed ... Full text Link to item Cite

A positioning QA procedure for 2D/2D (kV/MV) and 3D/3D (CT/CBCT) image matching for radiotherapy patient setup

Journal article Journal of Applied Clinical Medical Physics · January 1, 2009 Featured Publication A positioning QA procedure for Varian's 2D/2D (kV/MV) and 3D/3D (planCT/CBCT) matching was developed. The procedure was to check: (1) the coincidence of on-board imager (OBI), portal imager (PI), and cone beam CT (CBCT)'s isocenters (digital graticules) to ... Full text Cite

Analysis of image quality for real-time target tracking using simultaneous kV-MV imaging.

Journal article Med Phys · December 2008 Featured Publication Real-time tracking can provide high accuracy localization for a moving target and minimize the effect of motion. Simultaneous kV-MV imaging has been proposed as a real-time tracking technique by utilizing the existing kV on-board imager (OBI) and the MV el ... Full text Link to item Cite

Decision fusion of machine learning models to predict radiotherapyinduced lung pneumonitis

Journal article Proceedings 7th International Conference on Machine Learning and Applications Icmla 2008 · December 1, 2008 Featured Publication Combining different machine learning models (decision fusion) has been shown to be an effective method for estimating the underlying physical mechanism by allowing the models to reinforce each other when consensus exists, or, conversely, negate each other ... Full text Cite

Combining multiple models to generate consensus: application to radiation-induced pneumonitis prediction.

Journal article Med Phys · November 2008 Featured Publication The fusion of predictions from disparate models has been used in several fields to obtain a more realistic and robust estimate of the "ground truth" by allowing the models to reinforce each other when consensus exists, or, conversely, negate each other whe ... Full text Link to item Cite

Dosimetric characteristics of novalis Tx system with high definition multileaf collimator.

Journal article Med Phys · October 2008 Featured Publication A new Novalis Tx system equipped with a high definition multileaf collimator (HDMLC) recently became available to perform both image-guided radiosurgery and conventional radiotherapy. It is capable of delivering a highly conformal radiation dose with three ... Full text Link to item Cite

On-board four-dimensional digital tomosynthesis: first experimental results.

Journal article Med Phys · August 2008 Featured Publication The purpose of this study is to propose four-dimensional digital tomosynthesis (4D-DTS) for on-board analysis of motion information in three dimensions. Images of a dynamic motion phantom were reconstructed using acquisition scan angles ranging from 20 deg ... Full text Link to item Cite

A novel digital tomosynthesis (DTS) reconstruction method using a deformation field map.

Journal article Med Phys · July 2008 Featured Publication We developed a novel digital tomosynthesis (DTS) reconstruction method using a deformation field map to optimally estimate volumetric information in DTS images. The deformation field map is solved by using prior information, a deformation model, and new pr ... Full text Link to item Cite

Evaluation of an electron Monte Carlo dose calculation algorithm for electron beam.

Journal article J Appl Clin Med Phys · June 23, 2008 Featured Publication The electron Monte Carlo (eMC) dose calculation algorithm of the Eclipse treatment planning system is based heavily upon Monte Carlo simulation of the linac head and modeling of the linac beam characteristics with minimal measurement of beam data. Commissi ... Full text Open Access Link to item Cite

[Characteristics and affecting factors of denitrifying phosphorus removal in two-sludge sequencing batch reactor].

Journal article Huan Jing Ke Xue · June 2008 Featured Publication The characteristics of denitrifying phosphorus removal in a lab-scale two-sludge anaerobic-anoxic/nitrification SBR (A2 NSBR) system were studied fed with domestic wastewater. The influence of some key operation parameters, like C/P, C/N, and HRT, were exa ... Link to item Cite

Fast reconstruction of digital tomosynthesis using on-board images.

Journal article Med Phys · May 2008 Featured Publication Digital tomosynthesis (DTS) is a method to reconstruct pseudo three-dimensional (3D) volume images from two-dimensional x-ray projections acquired over limited scan angles. Compared with cone-beam computed tomography, which is frequently used for 3D image ... Full text Link to item Cite

The application of distance transformation on parameter optimization of inverse planning in intensity-modulated radiation therapy.

Journal article J Appl Clin Med Phys · April 16, 2008 Featured Publication In inverse planning for intensity-modulated radiation therapy (IMRT), the dose specification and related weighting factor of an objective function for involved organs is usually predefined by a single value and then iteratively optimized, subject to a set ... Full text Open Access Link to item Cite

The investigation on the location effect of external markers in respiratory-gated radiotherapy.

Journal article J Appl Clin Med Phys · April 16, 2008 Featured Publication PURPOSE: To investigate the effect of the marker placement on the correlation relationship between the motions of external markers and the internal target under different breathing patterns for several lung cancer patients. METHOD AND MATERIAL: To monitor ... Full text Open Access Link to item Cite

The impact of respiratory motion and treatment technique on stereotactic body radiation therapy for liver cancer.

Journal article Med Phys · April 2008 Featured Publication Stereotactic body radiation therapy (SBRT), which delivers a much higher fractional dose than conventional treatment in only a few fractions, is an effective treatment for liver metastases. For patients who are treated under free-breathing conditions, howe ... Full text Link to item Cite

Integration of cone-beam CT in stereotactic body radiation therapy.

Journal article Technol Cancer Res Treat · April 2008 Featured Publication This report describes the technique and initial experience using cone beam CT (CBCT) for localization of treatment targets in patients undergoing stereotactic body radiation therapy (SBRT). Patients selected for SBRT underwent 3-D or 4-D CT scans in a cust ... Full text Link to item Cite

Assessment of the residual error in soft tissue setup in patients undergoing partial breast irradiation: results of a prospective study using cone-beam computed tomography.

Journal article Int J Radiat Oncol Biol Phys · March 15, 2008 Featured Publication PURPOSE: On-board cone-beam computed tomography (CBCT) provides soft tissue information that may improve setup accuracy in patients undergoing accelerated partial breast irradiation (APBI). We used CBCT to assess the residual error in soft tissue after two ... Full text Link to item Cite

On-line re-optimization of prostate IMRT plans for adaptive radiation therapy.

Journal article Phys Med Biol · February 7, 2008 Featured Publication For intermediate and high risk prostate cancer, both the prostate gland and seminal vesicles are included in the clinical target volume. Internal motion patterns of these two organs vary, presenting a challenge for adaptive treatment. Adaptive techniques s ... Full text Link to item Cite

Automatic registration between reference and on-board digital tomosynthesis images for positioning verification.

Journal article Med Phys · February 2008 Featured Publication The authors developed a hybrid multiresolution rigid-body registration technique to automatically register reference digital tomosynthesis (DTS) images with on-board DTS images to guide patient positioning in radiation therapy. This hybrid registration tec ... Full text Link to item Cite

Clinical assessment and characterization of a dual tube kilovoltage X-ray localization system in the radiotherapy treatment room.

Journal article J Appl Clin Med Phys · January 13, 2008 Featured Publication INTRODUCTION: Although flat-panel based X-ray imaging has been well tested in diagnostic radiology, its use as an image-guided-radiotherapy (IGRT) system in a treatment room is new and requires systematic assessment. MATERIALS AND METHODS: BrainLab Novalis ... Full text Open Access Link to item Cite

Using patient data similarities to predict radiation pneumonitis via a self-organizing map.

Journal article Phys Med Biol · January 7, 2008 Featured Publication This work investigates the use of the self-organizing map (SOM) technique for predicting lung radiation pneumonitis (RP) risk. SOM is an effective method for projecting and visualizing high-dimensional data in a low-dimensional space (map). By projecting p ... Full text Link to item Cite

Evaluation of Image Enhancement Method on Target Registration Using Cone Beam CT in Radiation Therapy.

Journal article Clin Med Oncol · 2008 Featured Publication An intensity based six-degree image registration algorithm between cone-beam CT (CBCT) and planning CT has been developed for image-guided radiation therapy (IGRT). CT images of an anthropomorphic chest phantom were acquired using conventional CT scanner a ... Full text Link to item Cite

Use of the BrainLAB ExacTrac X-Ray 6D system in image-guided radiotherapy.

Journal article Med Dosim · 2008 Featured Publication The ExacTrac X-Ray 6D image-guided radiotherapy (IGRT) system will be described and its performance evaluated. The system is mainly an integration of 2 subsystems: (1) an infrared (IR)-based optical positioning system (ExacTrac) and (2) a radiographic kV x ... Full text Link to item Cite

Comparison of radiation doses between cone beam CT and multi detector CT: TLD measurements.

Journal article Radiat Prot Dosimetry · 2008 Featured Publication In recent years, wide beam computed tomography (CT) technique has become standard in radiation oncology whereas there is little information about radiation dose assessments for the technique. A point dose measurement method was employed to assess the radia ... Full text Link to item Cite

A phantom study on target localization accuracy using cone-beam computed tomography.

Journal article Clin Med Oncol · 2008 Featured Publication The purpose of this study is to evaluate the 3-dimensional target localization accuracy of cone-beam computed tomography (CBCT) using an on-board imager (OBI). An anthropomorphic pelvis phantom was used to simulate a range of offsets in the three translati ... Full text Link to item Cite

Response to comments by Dr. Luijik and Dr. Schippers

Journal article Medical Physics · January 1, 2008 Featured Publication Full text Cite

Evaluation of an electron Monte Carlo dose calculation algorithm for electron beams

Journal article Journal of Applied Clinical Medical Physics · January 1, 2008 Featured Publication The electron Monte Carlo (eMC) dose calculation algorithm of the Eclipse treatment planning system is based heavily upon Monte Carlo simulation of the linac head and modeling of the linac beam characteristics with minimal measurement of beam data. Commissi ... Full text Cite

An on-line adaptive radiation therapy system for intensity modulated radiation therapy: An application of multi-objective optimization

Journal article Journal of Industrial and Management Optimization · January 1, 2008 Featured Publication Radiation therapy (RT) is a non-invasive and highly ekective treatment option for Prostate cancer. The goal is to deliver the prescription dose to the tumor (prostate) while minimizing the damages to the surrounding healthy organs namely bladder, rectum, a ... Full text Cite

Application of distance transformation on parameter optimization of inverse planning in intensity-modulated radiation therapy

Journal article Journal of Applied Clinical Medical Physics · January 1, 2008 Featured Publication In inverse planning for intensity-modulated radiation therapy (IMRT), the dose specification and related weighting factor of an objective function for involved organs is usually predefined by a single value and then iteratively optimized, subject to a set ... Full text Cite

Investigation of the location effect of external markers in respiratory-gated radiotherapy

Journal article Journal of Applied Clinical Medical Physics · January 1, 2008 Featured Publication In 7 lung and breast cancer patients, we investigated the location effect of external markers on the correlation between the motions of external markers and of an internal target under various breathing patterns. Our department developed a tumor tracking s ... Full text Cite

Clinical assessment and characterization of a dual tube kilovoltage X-ray localization system in the radiotherapy treatment room

Journal article Journal of Applied Clinical Medical Physics · January 1, 2008 Featured Publication Although flat-panel kilovoltage X-ray imaging devices have been well tested for clinical use in diagnostic radiology, their use as a part of an image-guided radiation therapy (IGRT) system in a treatment room is new and requires systematic assessment. We u ... Full text Cite

The impact of advanced technologies on treatment deviations in radiation treatment delivery.

Journal article Int J Radiat Oncol Biol Phys · December 1, 2007 Featured Publication PURPOSE: To assess the impact of new technologies on deviation rates in radiation therapy (RT). METHODS AND MATERIALS: Treatment delivery deviations in RT were prospectively monitored during a time of technology upgrade. In January 2003, our department had ... Full text Link to item Cite

Cone-beam CT localization of internal target volumes for stereotactic body radiotherapy of lung lesions.

Journal article Int J Radiat Oncol Biol Phys · December 1, 2007 Featured Publication PURPOSE: In this study, we investigate a technique of matching internal target volumes (ITVs) in four-dimensional (4D) simulation computed tomography (CT) to the composite target volume in free-breathing on-board cone-beam (CB) CT. The technique is illustr ... Full text Link to item Cite

On-board patient positioning for head-and-neck IMRT: comparing digital tomosynthesis to kilovoltage radiography and cone-beam computed tomography.

Journal article Int J Radiat Oncol Biol Phys · October 1, 2007 Featured Publication PURPOSE: High-precision intensity-modulated radiotherapy demands high patient positioning accuracy. On-board digital tomosynthesis (DTS) provides three-dimensional (3D) image guidance for daily positioning with a lower imaging dose, faster acquisition, and ... Full text Link to item Cite

Investigation of the support vector machine algorithm to predict lung radiation-induced pneumonitis.

Journal article Med Phys · October 2007 Featured Publication The purpose of this study is to build and test a support vector machine (SVM) model to predict for the occurrence of lung radiation-induced Grade 2+ pneumonitis. SVM is a sophisticated statistical technique capable of separating the two categories of patie ... Full text Link to item Cite

Accelerating reconstruction of reference digital tomosynthesis using graphics hardware.

Journal article Med Phys · October 2007 Featured Publication The successful implementation of digital tomosynthesis (DTS) for on-board image guided radiation therapy (IGRT) requires fast DTS image reconstruction. Both target and reference DTS image sets are required to support an image registration application for I ... Full text Link to item Cite

The management of imaging dose during image-guided radiotherapy: report of the AAPM Task Group 75.

Journal article Med Phys · October 2007 Featured Publication Radiographic image guidance has emerged as the new paradigm for patient positioning, target localization, and external beam alignment in radiotherapy. Although widely varied in modality and method, all radiographic guidance techniques have one thing in com ... Full text Link to item Cite

Minimizing image noise in on-board CT reconstruction using both kilovoltage and megavoltage beam projections.

Journal article Med Phys · September 2007 Featured Publication We studied a recently proposed aggregated CT reconstruction technique which combines the complementary advantages of kilovoltage (kV) and megavoltage (MV) x-ray imaging. Various phantoms were imaged to study the effects of beam orientations and geometry of ... Full text Link to item Cite

A neural network model to predict lung radiation-induced pneumonitis.

Journal article Med Phys · September 2007 Featured Publication A feed-forward neural network was investigated to predict the occurrence of lung radiation-induced Grade 2+ pneumonitis. The database consisted of 235 patients with lung cancer treated using radiotherapy, of whom 34 were diagnosed with Grade 2+ pneumonitis ... Full text Link to item Cite

Evaluation of three types of reference image data for external beam radiotherapy target localization using digital tomosynthesis (DTS).

Journal article Med Phys · August 2007 Featured Publication Digital tomosynthesis (DTS) is a fast, low-dose three-dimensional (3D) imaging approach which yields slice images with excellent in-plane resolution, though low plane-to-plane resolution. A stack of DTS slices can be reconstructed from a single limited-ang ... Full text Link to item Cite

Comparison of similarity measures for rigid-body CT/Dual X-ray image registrations.

Journal article Technol Cancer Res Treat · August 2007 Featured Publication A set of experiments were conducted to evaluate six similarity measures for intensity-based rigid-body 3D/2D image registration. Similarity measure is an index that measures the similarity between a digitally reconstructed radiograph (DRR) and an x-ray pla ... Full text Link to item Cite

Predicting lung radiotherapy-induced pneumonitis using a model combining parametric Lyman probit with nonparametric decision trees.

Journal article Int J Radiat Oncol Biol Phys · July 15, 2007 Featured Publication PURPOSE: To develop and test a model to predict for lung radiation-induced Grade 2+ pneumonitis. METHODS AND MATERIALS: The model was built from a database of 234 lung cancer patients treated with radiotherapy (RT), of whom 43 were diagnosed with pneumonit ... Full text Link to item Cite

Self-consistent tumor control probability and normal tissue complication probability models based on generalized EUDa).

Journal article Med Phys · July 2007 Featured Publication Traditional methods to compute the tumor control probability (TCP) or normal tissue complication probability (NTCP) typically require a heterogeneous radiation dose distribution to be converted into a simple uniform dose distribution with an equivalent bio ... Full text Link to item Cite

Application of circumferencial myocardial function maps of tissue Doppler in patients with acute myocardial infarction

Journal article Chinese Journal of Medical Imaging Technology · July 1, 2007 Featured Publication Objective: A circumferencial functional map (CFM) of tissue Doppler imaging (TDI) was applied in patients with coronary artery disease (CAD) and the accuracy of CFM in assessment of ischemic region in patients with acute myocardial infarction (AMI) was eva ... Cite

A model for optimizing adenoviral delivery in human cancer gene therapy trials.

Journal article Hum Gene Ther · June 2007 Featured Publication Optimization of adenoviral delivery to the target volume is required for adenovirus-mediated cancer gene therapy to reach its maximal potential. The purpose of these studies was to develop a model of gene expression to improve adenovirus-mediated cancer ge ... Full text Link to item Cite

Reduction of organ motion by combined cardiac gating and respiratory gating.

Journal article Int J Radiat Oncol Biol Phys · May 1, 2007 Featured Publication PURPOSE: To investigate whether the effect of organ motion can be further reduced with the application of a cardiac gating technique, together with respiratory gating. METHODS AND MATERIALS: Axial and coronal images through the heart and liver were continu ... Full text Link to item Cite

Evaluation of an artificial intelligence guided inverse planning system: clinical case study.

Journal article Radiother Oncol · April 2007 Featured Publication PURPOSE: An artificial intelligence (AI) guided method for parameter adjustment of inverse planning was implemented on a commercial inverse treatment planning system. For evaluation purpose, four typical clinical cases were tested and the results from both ... Full text Link to item Cite

SU‐FF‐I‐37: An Adaptive Simultaneous Algebraic Reconstruction Technique

Journal article Medical Physics · January 1, 2007 Purpose: To improve the computational efficiency of Algebraic Reconstruction Technique (ART), and suppress the “stripping” artifacts due to ART like ray‐by‐ray update, especially in cone‐beam reconstruction. Method and Materials: Inspired by Adaptive ART ( ... Full text Cite

SU‐EE‐A3‐06: Onboard SPECT: Functional‐Image‐Based Target Localization

Journal article Medical Physics · January 1, 2007 Purpose: To investigate clinical feasibility for functional‐image‐based target localization via onboard single photon emission computed tomography (onboard SPECT). Specifically, to understand lesion visibility and signal‐to‐noise ratio (SNR) of onboard SPE ... Full text Cite

TH‐D‐M100E‐07: Determining the Geometric and Dosimetric Accuracy of MRI Based IMRT Treatment Plan for Patients with Prostate, Brain, and Head and Neck Cancers

Journal article Medical Physics · January 1, 2007 Purpose: To determine the geometric and dosimetric accuracy of MRI‐based IMRT treatment plan for patients with prostate, brain, and head and neck cancers. Methods and Material: CT simulation images were obtained for prostate, brain and head and neck cancer ... Full text Cite

MO‐D‐M100F‐01: Emerging Techniques Using Digital Tomosynthesis

Journal article Medical Physics · January 1, 2007 In‐room radiolographic imaging systems is being rapidly implemented in routine clinical operations for target localization. A typical system consists of a kV x‐ray source and an amorphous‐silicon flat panel detector mounted orthogonally to the MV‐beam axis ... Full text Cite

SU‐FF‐T‐419: Time‐Delay Measurement of Phase Gated Treatment with a Varian Real‐Time Position Management System Using Computed Radiography

Journal article Medical Physics · January 1, 2007 Purpose: Respiratory gating systems have been developed to reduce treatment uncertainty caused by organ motions related to respiration. The time‐delay between when the gating signal is triggered and when the beam is turned on may affect the actual radiatio ... Full text Cite

MO‐SAMS‐AUD‐01: Daily Localization — I: Kilovolt Imaging

Journal article Medical Physics · January 1, 2007 As high‐precision 3‐D conformal radiation therapy and intensity‐modulated radiation therapy have become standard practice, radiographic imaging using kilovoltage (kV) x‐ray sources has been rapidly implemented for in‐room target localization and patient po ... Full text Cite

Advanced radiation therapy technologies in the treatment of rectal and anal cancer: intensity-modulated photon therapy and proton therapy.

Journal article Clin Colorectal Cancer · January 2007 Featured Publication Intensity-modulated photon radiation therapy (RT; IMRT) and proton therapy are advanced radiation technologies that permit improved conformation of radiation dose to target structures while limiting irradiation of surrounding normal tissues. Application of ... Full text Link to item Cite

Dosimetric feasibility of cone-beam CT-based treatment planning compared to CT-based treatment planning.

Journal article Int J Radiat Oncol Biol Phys · December 1, 2006 Featured Publication PURPOSE: Cone-beam computed tomography (CBCT) images are currently used for positioning verification. However, it is yet unknown whether CBCT could be used in dose calculation for replanning in adaptive radiation therapy. This study investigates the dosime ... Full text Link to item Cite

A methodology for using SPECT to reduce intensity-modulated radiation therapy (IMRT) dose to functioning lung.

Journal article Int J Radiat Oncol Biol Phys · December 1, 2006 Featured Publication PURPOSE: Single photon emission computed tomography (SPECT) provides a map of the spatial distribution of lung perfusion. Thus, SPECT guidance can be used to divert dose away from higher-functioning lung, potentially reducing lung toxicity. We present a me ... Full text Link to item Cite

A quality assurance program for the on-board imager®.

Journal article Med Phys · November 2006 Featured Publication To develop a quality assurance (QA) program for the On-Board Imager (OBI) system and to summarize the results of these QA tests over extended periods from multiple institutions. Both the radiographic and cone-beam computed tomography (CBCT) mode of operati ... Full text Link to item Cite

The correlation evaluation of a tumor tracking system using multiple external markers.

Journal article Med Phys · November 2006 Featured Publication The purpose of this study is to evaluate the correlations between external markers and internal targets for radiation therapy of lung cancer patients. Using an infrared camera system coupled with a clinical simulator, the simultaneous motions of multiple e ... Full text Link to item Cite

Digital tomosynthesis with an on-board kilovoltage imaging device.

Journal article Int J Radiat Oncol Biol Phys · May 1, 2006 Featured Publication PURPOSE: To generate on-board digital tomosynthesis (DTS) and reference DTS images for three-dimensional image-guided radiation therapy (IGRT) as an alternative to conventional portal imaging or on-board cone-beam computed tomography (CBCT). METHODS AND MA ... Full text Link to item Cite

Postoperative radiosurgery for malignant spinal tumors.

Journal article Neurosurgery · May 2006 Featured Publication OBJECTIVE: Although, as a primary therapy, radiosurgery for spinal tumors is becoming more common in clinical practice and is associated with encouraging clinical results, we wanted to evaluate outcomes after radiosurgery in a series of postoperative patie ... Full text Link to item Cite

Physics and imaging for targeting of oligometastases.

Journal article Semin Radiat Oncol · April 2006 Featured Publication Oligometastases refer to metastases that are limited in number and location and are amenable to regional treatment. The majority of these metastases appear in the brain, lung, liver, and bone. Although the focus of interest in the past within radiation onc ... Full text Link to item Cite

A technique of using gated-CT images to determine internal target volume (ITV) for fractionated stereotactic lung radiotherapy.

Journal article Radiother Oncol · February 2006 Featured Publication BACKGROUND AND PURPOSE: To develop and evaluate a technique and procedure of using gated-CT images in combination with PET image to determine the internal target volume (ITV), which could reduce the planning target volume (PTV) with adequate target coverag ... Full text Link to item Cite

Adaptive prediction of internal target motion using external marker motion: a technical study.

Journal article Phys Med Biol · January 7, 2006 Featured Publication An adaptive prediction approach was developed to infer internal target position by external marker positions. First, a prediction model (or adaptive neural network) is developed to infer target position from its former positions. For both internal target a ... Full text Link to item Cite

Towards four dimensional (4D) dosimetry for radiation-therapy.

Journal article J Phys Conf Ser · 2006 Featured Publication Full text Link to item Cite

A technique for on-board CT reconstruction using both kilovoltage and megavoltage beam projections for 3D treatment verification.

Journal article Med Phys · September 2005 Featured Publication The technologies with kilovoltage (kV) and megavoltage (MV) imaging in the treatment room are now available for image-guided radiation therapy to improve patient setup and target localization accuracy. However, development of strategies to efficiently and ... Full text Link to item Cite

Time delay measurement for linac based treatment delivery in synchronized respiratory gating radiotherapy.

Journal article Med Phys · May 2005 Featured Publication A time delay in a respiratory gating system could cause an unexpected phase mismatch for synchronized gating radiotherapy. This study presents a method of identifying and measuring the time delay in a gating system. Various port films were taken for a moti ... Full text Link to item Cite

Effects of x-ray and CT image enhancements on the robustness and accuracy of a rigid 3D/2D image registration.

Journal article Med Phys · April 2005 Featured Publication A rigid body three-dimensional/two-dimensional (3D/2D) registration method has been implemented using mutual information, gradient ascent, and 3D texturemap-based digitally reconstructed radiographs. Nine combinations of commonly used x-ray and computed to ... Full text Link to item Cite

Dosimetric study using different leaf-width MLCs for treatment planning of dynamic conformal arcs and intensity-modulated radiosurgery.

Journal article Med Phys · February 2005 Featured Publication This paper systematically studied the dosimetric difference between a 3 mm micro multileaf collimator (MLC), a 5 mm MLC, and a 10 mm MLC for stereotactic radiosurgery using the Brainscan treatment planning system. Thirty-four cases treated with the dynamic ... Full text Link to item Cite

WE‐D‐T‐6E‐02: A Clinical Planning Tool for Optimization of Intensity Modulated Radiotherapy Parameters

Journal article Medical Physics · January 1, 2005 Purpose: To develop a clinical tool that incorporates novel strategies to optimize all involved parameters in IMRT treatment planning: (a) the number of beams, (b) beam orientations, and (c) fluence maps. Method and Materials: An IMRT planning tool was dev ... Full text Cite

SU‐FF‐T‐61: A Pseudo‐Tangential IMRT Technique for the Whole Large Left Breast Radiation Therapy Using Helios/Eclipse System

Journal article Medical Physics · January 1, 2005 Purpose: A pseudo‐tangential IMRT (PT‐IMRT) technique was developed to achieve high dose uniformity for the whole large left breast (separations >24 cm and volumes > 1200cc) radiation therapy and to reduce the early and late skin and subcutaneous reactions ... Full text Cite

SU‐FF‐T‐190: Daily Quality Assurance (QA) Procedure of On‐Board Imager (OBI)

Journal article Medical Physics · January 1, 2005 Purpose: Developed a daily QA procedure for checking; 1) the accuracy of the imager isocenter and 2) the auto couch motion accuracy of the On‐Board Imager (OBI) device developed by Varian. This QA procedure will assure that the imager isocenter matches the ... Full text Cite

SU‐FF‐T‐212: Quality Assurance (QA) Procedure of On‐Board Imager (OBI) for Portal Imaging

Journal article Medical Physics · January 1, 2005 Purpose: On‐board imager (OBI) has been implemented to improve the in‐room patient positioning. It is therefore important to establish quality assurance (QA) procedure to ensure proper functionality and operational accuracy. This report presents monthly OB ... Full text Cite

Adaptive algebraic reconstruction technique.

Journal article Med Phys · December 2004 Featured Publication Algebraic reconstruction techniques (ART) are iterative procedures for reconstructing objects from their projections. It is proven that ART can be computationally efficient by carefully arranging the order in which the collected data are accessed during th ... Full text Link to item Cite

Image-guided procedures for intensity-modulated spinal radiosurgery. Technical note.

Journal article J Neurosurg · November 2004 Featured Publication Radiosurgery for brain tumors has been well established in the radiation oncology and neurosurgery fields. Radiosurgery of extracranial tumors such as those involving the spine is, however, still in the early stage because of difficulties in patient immobi ... Link to item Cite

A novel needle-based miniature x-ray generating system.

Journal article Phys Med Biol · October 21, 2004 Featured Publication The basic concept, design and performance of a novel needle-based x-ray system for medical applications are reported. The main principle of the system is based on a two-stage production of x-rays. The system comprises a conventional x-ray tube with an Ag a ... Full text Link to item Cite

Novalis radiosurgery for metastatic spine tumors.

Journal article Neurosurg Clin N Am · October 2004 Featured Publication It is logical to anticipate that the field of spinal radiosurgery will evolve in a fashion similar to that seen for intracranial radiosurgery. Given the frequency of various pathologic entities that affect the spine, including those that have proven to be ... Full text Link to item Cite

Image-guided radiosurgery of head and neck cancers.

Journal article Otolaryngol Head Neck Surg · June 2004 Featured Publication OBJECTIVES: Radiosurgery precisely delivers a single high dose or a few fractionated doses of radiation to a localized tumor via the stereotactic approach. Some head and neck sites are suitable for radiosurgery since there is minimal or no organ motion. Th ... Full text Link to item Cite

A quantitative method for measuring gene expression magnitude and volume delivered by gene therapy vectors.

Journal article Mol Ther · April 2004 Featured Publication This study describes a quantitative method to measure the magnitude and distribution of gene expression following local delivery of an adenoviral vector containing the human sodium iodide symporter (hNIS) reporter gene into the canine prostate. Following s ... Full text Link to item Cite

The evolving role of stereotactic radiosurgery and stereotactic radiation therapy for patients with spine tumors.

Journal article J Neurooncol · 2004 Featured Publication Traditional management strategies for patients with spinal tumors have undergone considerable changes during the last 15 years. Significant improvements in digital imaging, computer processing, and treatment planning have provided the basis for the applica ... Full text Link to item Cite

A phantom study on the positioning accuracy of the Novalis Body system.

Journal article Med Phys · December 2003 Featured Publication A phantom study was conducted to investigate inherent positioning accuracy of an image-guided patient positioning system-the Novalis Body system for three-dimensional (3-D) conformal radiotherapy. This positioning system consists of two infrared (IR) camer ... Full text Link to item Cite

AI-guided parameter optimization in inverse treatment planning.

Journal article Phys Med Biol · November 7, 2003 Featured Publication An artificial intelligence (AI)-guided inverse planning system was developed to optimize the combination of parameters in the objective function for intensity-modulated radiation therapy (IMRT). In this system, the empirical knowledge of inverse planning w ... Full text Link to item Cite

Fuzzy logic guided inverse treatment planning.

Journal article Med Phys · October 2003 Featured Publication A fuzzy logic technique was applied to optimize the weighting factors in the objective function of an inverse treatment planning system for intensity-modulated radiation therapy (IMRT). Based on this technique, the optimization of weighting factors is guid ... Full text Link to item Cite

GENIS: gene expression of sodium iodide symporter for noninvasive imaging of gene therapy vectors and quantification of gene expression in vivo.

Journal article Mol Ther · September 2003 Featured Publication With the goal of optimizing adenovirus-mediated suicide gene therapy for prostate cancer, we have developed a method based on the human sodium iodide symporter (hNIS) that allows for noninvasive monitoring of adenoviral vectors and quantification of gene e ... Full text Link to item Cite

Point dose verification for intensity modulated radiosurgery using Clarkson's method.

Journal article Med Phys · August 2003 Featured Publication In clinical radiation physics chart checking, the dose calculation results generated by computer treatment planning software are usually verified by an independent computerized monitor unit calculation routine, or by "hand calculation" using percent depth ... Full text Link to item Cite

Image-guided and intensity-modulated radiosurgery for patients with spinal metastasis.

Journal article Cancer · April 15, 2003 Featured Publication BACKGROUND: Radiosurgery can deliver a single, large radiation dose to a localized tumor using a stereotactic approach and hence, requires accurate and precise delivery of radiation to the target. Of the extracranial organ targets, the spine is considered ... Full text Link to item Cite

A technique of intensity-modulated radiosurgery (IMRS) for spinal tumors.

Journal article Med Phys · December 2002 Featured Publication This study is to demonstrate the feasibility of spinal radiosurgery using an image-guided intensity-modulated radiosurgical (IMRS) procedure. A dedicated Novalis shaped beam surgery unit equipped with a built-in micro-multileaf collimator (mMLC) with a sin ... Full text Link to item Cite

Radiosurgical treatment for Ewing's sarcoma of the lumbar spine: case report.

Journal article Spine (Phila Pa 1976) · November 1, 2002 Featured Publication STUDY DESIGN: Case report. OBJECTIVES: The objective of this study was to document the long-term follow-up of a single case. SUMMARY OF BACKGROUND DATA: Radiosurgery is potentially a useful therapeutic option for spinal tumors. The authors present the unus ... Full text Link to item Cite

Accuracy of inhomogeneity correction in photon radiotherapy from CT scans with different settings.

Journal article Phys Med Biol · September 7, 2002 Featured Publication We report an investigation on the accuracy of inhomogeneity correction in photon radiotherapy from CT scans with different settings. Specifically, the dosimetric differences from different CT scan parameters (kV, mAs) to phantoms and from different Hounsfi ... Full text Link to item Cite

Dosimetric characteristics of Novalis shaped beam surgery unit.

Journal article Med Phys · August 2002 Featured Publication The dosimetric characteristics of a new dedicated radiosurgical treatment unit are systematically measured in terms of its percent depth dose, beam profile, and relative scatter factor. High-resolution diode detector, mini-ion-chamber detector, and convent ... Full text Link to item Cite

A three-dimensional deformable model for segmentation of human prostate from ultrasound images.

Journal article Med Phys · October 2001 Featured Publication Segmentation of human prostate from ultrasound (US) images is a crucial step in radiation therapy, especially in real-time planning for US image-guided prostate seed implant. This step is critical to determine the radioactive seed placement and to ensure t ... Full text Link to item Cite

Extracranial radiosurgery: immobilizing liver motion in dogs using high-frequency jet ventilation and total intravenous anesthesia.

Journal article Int J Radiat Oncol Biol Phys · January 1, 2001 Featured Publication PURPOSE: Extracranial radiosurgery requires control of organ motion. The purpose of this study is to quantitatively determine the extent of liver motion in anesthetized dogs with continuous i.v. propofol infusion with or without muscle relaxants and high-f ... Full text Link to item Cite

Adaptive portal CT reconstruction: a simulation study.

Journal article Med Phys · October 2000 Featured Publication In radiotherapy, radiation treatment beams contain valuable information for patient setup verification. These beams may be used for portal CT reconstruction. However, direct use of the beam data for reconstruction may yield inadequate CT images simply beca ... Full text Link to item Cite

Optimization of inverse treatment planning using a fuzzy weight function.

Journal article Med Phys · April 2000 Featured Publication A fuzzy approach has been applied to inverse treatment planning optimization in radiation therapy. The proposed inverse-planning algorithm optimizes both the intensity-modulated beam (IMB) and the normal tissue prescription. In the IMB optimization, we dev ... Full text Link to item Cite

Soft optimization with fuzzy weight function

Journal article IEEE International Conference on Fuzzy Systems · December 1, 1999 Featured Publication We describe a new class of optimization method based on the theory of classic minimum using a fuzzy weight function. The technique is applied to the problem of normal tissue prescription optimization in conformal radiotherapy. The performance of the new al ... Cite

Treatment field shape verification using elliptic Fourier transform.

Journal article Med Phys · November 1999 Featured Publication An automated field shape correlation technique based on elliptic Fourier transform (EFT) is developed to verify the radiation treatment field in digital portal images. In this method, the edge of the treatment field is initially extracted from the portal i ... Full text Link to item Cite

Structures of yeast vesicle trafficking proteins.

Journal article Protein Sci · November 1999 Featured Publication In protein transport between organelles, interactions of v- and t-SNARE proteins are required for fusion of protein-containing vesicles with appropriate target compartments. Mammalian SNARE proteins have been observed to interact with NSF and SNAP, and yea ... Full text Link to item Cite

Two-dimensional direction-based interpolation with local centered moments

Journal article Graphical Models and Image Processing · January 1, 1999 Featured Publication Interpolation is generally needed to visualize medical images from a limited number of sliced tomographic images such as CT. In this paper, a novel gray-scale image interpolation method, for interpolating two-dimensional images accurately and efficiently, ... Full text Cite

Variation method for inverse treatment planning

Journal article Medical Physics · January 1, 1999 Featured Publication A new inverse planning method based on the theory of variation is developed for the computation of beam intensities that produce highly conformal dose distributions to the target volume that have an arbitrary complex geometry. It is shown that the objectiv ... Full text Cite

MR image-guided portal verification for brain treatment field.

Journal article Int J Radiat Oncol Biol Phys · February 1, 1998 Featured Publication PURPOSE: To investigate a method for the generation of digitally reconstructed radiographs directly from MR images (DRR-MRI) to guide a computerized portal verification procedure. METHODS AND MATERIALS: Several major steps were developed to perform an MR i ... Full text Link to item Cite

Oncologic image compression using both wavelet and masking techniques.

Journal article Med Phys · December 1997 Featured Publication A new algorithm has been developed to compress oncologic images using both wavelet transform and field masking methods. A compactly supported wavelet transform is used to decompose the original image into high- and low-frequency subband images. The region- ... Full text Link to item Cite

Two-dimensional refinement scheme of direction-based interpolation with discrete orthogonal polynomial decomposition

Journal article Proceedings of SPIE the International Society for Optical Engineering · December 1, 1997 Featured Publication In this paper, a novel direction-based interpolation approach with discrete orthogonal polynomial decomposition is introduced. A 2D digital image is usually regarded as a sampling of an underlying 2D continuous function, which is called an image field. Whe ... Cite

Automated extraction of pelvic features in portal and simulation images

Journal article Proceedings of SPIE the International Society for Optical Engineering · December 1, 1996 Featured Publication A new approach, a pyramid template matching as guided by a snake, is developed for the extraction of pelvic features in both portal and simulation images. Initially, the treatment field edge was extracted using a Canny edge detector. A template modeled usi ... Full text Cite

The effect of detector size to the broadening of the penumbra--a computer simulated study.

Journal article Med Phys · August 1996 Featured Publication The effect of detector size to the broadening of the measured beam penumbra has been a subject of numerous studies. Based on measured data, linear and quadratic curves have been proposed to describe the relationship between the measured penumbra width, bet ... Full text Link to item Cite

An observer study for direct comparison of clinical efficacy of electronic to film portal images.

Journal article Int J Radiat Oncol Biol Phys · July 15, 1996 Featured Publication PURPOSE: To directly compare clinical efficacy of electronic to film portal images. METHODS AND MATERIALS: An observer study was designed to compare clinical efficacy of electronic to film portal images acquired using a liquid matrix ion-chamber electronic ... Full text Link to item Cite

Portal image feature extraction by hierarchical region processing technique

Journal article Proceedings of the IEEE International Conference on Systems Man and Cybernetics · December 1, 1995 Featured Publication We describe in this paper a novel hierarchical region processing technique for the extraction of features from portal images. Feature extraction is an essential component in the computerized registration of portal images for radiation treatment verificatio ... Cite

Physical penumbra change of beam profile due to film digitization.

Journal article Med Phys · June 1995 Featured Publication Full text Link to item Cite

A technique of automating compensator design for lung inhomogeneity correction using an electron portal imaging device.

Journal article Med Phys · November 1994 Featured Publication A technique of automating compensator design for lung inhomogeneity correction using an electron portal imaging device (EPID) has been investigated. This technique utilizes exit-radiation information as detected by an EPID to determine the thickness of the ... Full text Link to item Cite

Input/output characteristics of a matrix ion-chamber electronic portal imaging device.

Journal article Med Phys · September 1994 Featured Publication The input/output characteristics of a matrix liquid ion-chamber electronic portal imaging device (EPID) are investigated to elucidate the imaging properties of EPIDs. The radiation input to the detector, represented by dose rate, and the pixel value output ... Full text Link to item Cite

Computerized detection of masses in digital mammograms: automated alignment of breast images and its effect on bilateral-subtraction technique.

Journal article Med Phys · March 1994 Featured Publication An automated technique for the alignment of right and left breast images has been developed for use in the computerized analysis of bilateral breast images. In this technique, the breast region is first identified in each digital mammogram by use of histog ... Full text Link to item Cite

Effect of case selection on the performance of computer-aided detection schemes.

Journal article Med Phys · February 1994 Featured Publication The choice of clinical cases used to train and test a computer-aided diagnosis (CAD) scheme can affect the test results (i.e., error rate). In this study, we deliberately modified the components of our testing database to study the effects of this modifica ... Full text Link to item Cite

Computerized detection of masses in digital mammograms: investigation of feature-analysis techniques.

Journal article J Digit Imaging · February 1994 Featured Publication Mammographic screening of asymptomatic women has shown effectiveness in the reduction of breast cancer mortality. We are developing a computerized scheme for the detection of mammographic masses as an aid to radiologists in mammographic screening programs. ... Full text Link to item Cite

Comparison of bilateral-subtraction and single-image processing techniques in the computerized detection of mammographic masses.

Journal article Invest Radiol · June 1993 Featured Publication RATIONALE AND OBJECTIVES: Identification of regions as possible masses on digitized screen film mammograms is an important initial step in the computerized detection of breast carcinomas. Possible masses may be initially extracted using criteria based on o ... Full text Link to item Cite

Evaluation of imaging properties of a laser film digitizer.

Journal article Phys Med Biol · January 1992 Featured Publication In this paper we provide a quantitative assessment of the basic imaging properties of a laser film digitizer. The characteristic curve of the digitizer was determined in terms of the relationship between input optical density and output pixel value. Spatia ... Full text Link to item Cite

Direct comparison of conventional and computed radiography with a dual-image recording technique.

Journal article Radiographics · March 1991 Featured Publication To compare the image quality of computed radiographic (CR) with conventional screen-film images, the authors used a dual-image recording technique. Images were simultaneously acquired with a conventional screen-film combination and a storage-phosphor imagi ... Full text Link to item Cite

Computerized detection of masses in digital mammograms: analysis of bilateral subtraction images.

Journal article Med Phys · 1991 Featured Publication A computerized scheme is being developed for the detection of masses in digital mammograms. Based on the deviation from the normal architectural symmetry of the right and left breasts, a bilateral subtraction technique is used to enhance the conspicuity of ... Full text Link to item Cite

Data compression: effect on diagnostic accuracy in digital chest radiography.

Journal article Radiology · January 1991 Featured Publication High-resolution digital images make up very large data sets that are relatively slow to transmit and expensive to store. Data compression techniques are being developed to address this problem, but significant image deterioration can occur at high compress ... Full text Link to item Cite

Comparison of imaging properties of a computed radiography system and screen-film systems.

Journal article Med Phys · 1991 Featured Publication To compare the diagnostic quality of images obtained with a computed radiography (CR) system based on storage phosphor technology with that obtained with conventional screen-film systems, a dual-image recording technique was devised. With this technique, a ... Full text Link to item Cite

Development of a 'smart' workstation for use in mammography

Journal article Proceedings of SPIE the International Society for Optical Engineering · January 1, 1991 Featured Publication We are developing various computer-vision schemes for the detection of masses and microcalcifications in digital mammograms (1-7). However, for the effective and efficient implementation of computer-aided diagnosis (CAD), appropriate man-machine interfaces ... Cite

Computer-vision system for the detection and characterization of masses for use in mammographic screening programs

Journal article Proceedings of SPIE the International Society for Optical Engineering · January 1, 1991 Featured Publication Studies have shown that early detection of breast cancer through periodic mammographic screening of asymptomatic women could reduce breast cancer mortality by 30-50%. However, screening yields a high volume of mammograms requiring interpretation. In additi ... Cite

Investigation of methods for the computerized detection and analysis of mammographic masses

Journal article Proceedings of SPIE the International Society for Optical Engineering · December 1, 1990 Featured Publication At present, mammography is the most effective method for the early detection of breast cancer. Detection and classification of masses in mammograms are among the most important and difficult tasks performed by radiologists. Various studies have indicated t ... Cite

Evaluation of basic imaging properties of a new digital chest system

Journal article Proceedings of SPIE the International Society for Optical Engineering · July 1, 1990 Featured Publication A prototype digital chest system, which uses storage phosphor technology and has the advantages over existing computed radiography systems (CR) of compactness and immediate image display, is being evaluated in our laboratory. We evaluated the imaging prope ... Full text Cite

Measurement of the presampling modulation transfer function of film digitizers using a curve fitting technique.

Journal article Med Phys · 1990 Featured Publication A curve fitting technique combined with an angulated slit image has been developed for the measurement of the presampling modulation transfer function (MTF) of film digitizers. The noisy line spread functions (LSFs) acquired from an angulated slit image ar ... Full text Link to item Cite

Pulmonary nodules: computer-aided detection in digital chest images.

Journal article Radiographics · January 1990 Featured Publication Currently, radiologists fail to detect pulmonary nodules in up to 30% of cases with actually positive findings. Diagnoses may be missed due to camouflaging effects of anatomic background, subjective and varying decision criteria, or distractions in clinica ... Full text Link to item Cite

Image-processing techniques used in the computer-aided detection of radiographic lesions in anatomic background

Journal article Proceedings of SPIE the International Society for Optical Engineering · June 27, 1988 Full text Cite

Is a single isocenter sufficient for volumetric modulated arc therapy radiosurgery when multiple itracranial metastases are spatially dispersed?

Journal article Med Dosim Previous work demonstrated improved dosimetry of single isocenter volumetric modulated arc therapy (VMAT) of multiple intracranial targets when they are located ≤ 4cm from isocenter because of narrower multileaf collimators (MLCs). In follow-up, we sought ... Full text Link to item Cite

Radiosurgery treatment planning using conformal arc informed volumetric modulated arc therapy.

Journal article Med Dosim Linac based radiosurgery to multiple metastases is commonly planned with volumetric modulated arc therapy (VMAT) as it effectively achieves high conformality to complex target arrangements. However, as the number of targets increases, VMAT can struggle to ... Full text Link to item Cite