Scholars@Duke
Mark Oldham

Mark Oldham

Professor of Radiation Oncology
Radiation Oncology
mark.oldham@duke.edu
Box 3295 Med Ctr, Durham, NC
04214 Duke South Clinics, Duke South Clinics, Durham, NC 27710

Selected Publications

Clinical applicability of Linac-integrated CBCT based NIPAM 3D dosimetry: a dual-institutional investigation.

Journal Article Phys Med Biol · July 16, 2024 Objective.To develop and benchmark a novel 3D dose verification technique consisting of polymer gel dosimetry (PGD) with cone-beam-CT (CBCT) readout through a two-institution study. The technique has potential for wide and robust applicability through reli ... Full text Link to item Cite

Validation of complex radiotherapy techniques using polymer gel dosimetry.

Journal Article Phys Med Biol · March 20, 2024 Modern radiotherapy delivers highly conformal dose distributions to irregularly shaped target volumes while sparing the surrounding normal tissue. Due to the complex planning and delivery techniques, dose verification and validation of the whole treatment ... Full text Link to item Cite

Clinical Applications and Monte Carlo Validation of a fully integrated 3D dosimetry system

Conference Journal of Physics: Conference Series · January 1, 2024 A comprehensive 3D dosimetry system consisting of the ClearView™ 3D dosimeter, VistaScan™ optical CT scanner, and VistaAce™ analysis software is commercially available and has the potential to be a strong verification tool with widespread applications. The ... Full text Cite

Single-fraction Radiation Treatment Dose Response in a Genetically Engineered Mouse Model of Medulloblastoma.

Journal Article Radiat Res · December 1, 2023 Medulloblastoma is the most common malignant brain tumor of children. Although standard of care radiotherapy for pediatric medulloblastoma (PM) can lead to long-term remission or cure in many patients, it can also cause life-long cognitive impairment and o ... Full text Link to item Cite

Investigation of a 3D dosimetry system utilizing radio-chromic gel and telecentric optical-CT readout.

Journal Article Med Phys · September 2023 BACKGROUND: Sophisticated modern radiation therapy treatments require comprehensive validation in 3D. PURPOSE: Investigation and characterization of a novel 3D dosimetry system consisting of ClearView radiochromic gel dosimeters (commercially available fro ... Full text Link to item Cite

The Effect of Atm Loss on Radiosensitivity of a Primary Mouse Model of Pten-Deleted Brainstem Glioma.

Journal Article Cancers (Basel) · September 17, 2022 Diffuse midline gliomas arise in the brainstem and other midline brain structures and cause a large proportion of childhood brain tumor deaths. Radiation therapy is the most effective treatment option, but these tumors ultimately progress. Inhibition of th ... Full text Link to item Cite

Evaluation of a method to measure fluorescent cell burden in complex culture systems.

Journal Article Biomed Phys Eng Express · April 27, 2022 Purpose. This work introduces and evaluates a method for accurate in-vitro measurement of fluorescent cell burden in complex 3D-culture conditions.Methods.The Fluorescent Cell Burden (FCB) method was developed to analyze the burden of 4T1 mCherry-expressin ... Full text Link to item Cite

An investigation of kV mini-GRID spatially fractionated radiation therapy: dosimetry and preclinical trial.

Journal Article Phys Med Biol · February 18, 2022 Objective. To develop and characterize novel methods of extreme spatially fractionated kV radiation therapy (including mini-GRID therapy) and to evaluate efficacy in the context of a pre-clinical mouse study.Approach. Spatially fractionated GRIDs were prec ... Full text Link to item Cite

Development of a practical clinical application of NIPAM kV-CBCT dosimetry

Conference Journal of Physics: Conference Series · January 24, 2022 We report our progress towards developing a clinical application of NIPAM kV-CBCT dosimetry. The goal is to develop a practical kV-MV isocenter verification test for which the measurement and analysis can be carried out quickly (within an hour), and that e ... Full text Cite

Preface

Conference Journal of Physics: Conference Series · January 24, 2022 Full text Cite

Feasibility of a Novel 3D Dosimetry System for Commissioning of Single Isocenter Multitarget SRS Treatment

Conference INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS · 2022 Cite

Sensitization of Endothelial Cells to Ionizing Radiation Exacerbates Delayed Radiation Myelopathy in Mice.

Journal Article Radiat Res · November 1, 2021 Delayed radiation myelopathy is a rare, but significant late side effect from radiation therapy that can lead to paralysis. The cellular and molecular mechanisms leading to delayed radiation myelopathy are not completely understood but may be a consequence ... Full text Link to item Cite

Report of AAPM Task Group 155: Megavoltage photon beam dosimetry in small fields and non-equilibrium conditions.

Journal Article Med Phys · October 2021 Small-field dosimetry used in advance treatment technologies poses challenges due to loss of lateral charged particle equilibrium (LCPE), occlusion of the primary photon source, and the limited choice of suitable radiation detectors. These challenges great ... Full text Link to item Cite

A method for generating intensity-modulated radiation therapy fields for small animal irradiators utilizing 3D-printed compensator molds.

Journal Article Med Phys · September 2020 Featured Publication PURPOSE: The purpose of this study was to investigate the feasibility of using fused deposition modeling (FDM) three-dimensional (3D) printer to generate radiation compensators for high-resolution (~1 mm) intensity-modulated radiation therapy (IMRT) for sm ... Full text Link to item Cite

Comprehensive radiation and imaging isocenter verification using NIPAM kV-CBCT dosimetry.

Journal Article Med Phys · March 2020 PURPOSE: To develop and demonstrate a comprehensive method to directly measure radiation isocenter uncertainty and coincidence with the cone-beam computed tomography (kV-CBCT) imaging coordinate system that can be carried out within a typical quality assur ... Full text Link to item Cite

An investigation of a novel reusable radiochromic sheet for 2D dose measurement.

Journal Article Med Phys · December 2019 PURPOSE: Radiochromic film remains a useful and versatile clinical dosimetry tool. Current film options are single use. Here, we introduce a novel prototype two-dimensional (2D) radiochromic sheet, which optically clears naturally at room temperature after ... Full text Link to item Cite

Evaluation of UVA emission from x-ray megavoltage-irradiated tissues and phantoms.

Journal Article Phys Med Biol · November 21, 2019 RECA (Radiotherapy enhanced with Cherenkov photo-activation) is a proposed treatment where the anti-cancer drug psoralen is photo-activated in situ by UVA (Ultraviolet A, 320-400 nm) Cherenkov light (CL) produced directly by the treatment beam itself. In t ... Full text Link to item Cite

Feasibility of radiosurgery dosimetry using NIPAM 3D dosimeters and x-ray CT

Conference Journal of Physics: Conference Series · August 29, 2019 We investigated the feasibility of using N-isopropylacrylamide (NIPAM) dosimeters with x-ray CT to verify radiosurgery dose. Dosimeters were prepared at one facility and shipped to a second facility for irradiation. A simulation CT was acquired and plans p ... Full text Cite

Preface

Conference Journal of Physics: Conference Series · August 29, 2019 Full text Cite

Welcome Message

Conference Journal of Physics: Conference Series · August 29, 2019 Full text Cite

Preliminary characterization of the Duke Integrated-Lens Optical-CT scanner (DIOS)

Conference Journal of Physics: Conference Series · August 29, 2019 The present study investigates a cost effective and practical non-telecentric optical-CT scanner developed for 3D dosimetry, the Duke Integrated-Lens Optical-CT scanner (DIOS). The DIOS system includes an upgraded light-collimating tank (the LC-tank) made ... Full text Cite

Preliminary investigation of a reusable radiochromic sheet for radiation dosimetry

Conference Journal of Physics: Conference Series · August 29, 2019 This work investigates a novel reusable radiochromic sheet developed as an economic film substitute or as a radiochromic bolus. The radiation-induced optical density (OD) change of the sheet is read-out with a commercial flat-bed optical scanner. An optimi ... Full text Cite

SRS and SBRT and advanced dosimetry: Duke experiences

Conference Journal of Physics: Conference Series · August 29, 2019 Stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) are among the most demanding of radiation therapy techniques in terms of requirements for high accuracy and conformality of treatment delivery. Compared to conventional treatmen ... Full text Cite

Delivered Dose Distribution Visualized Directly With Onboard kV-CBCT: Proof of Principle.

Journal Article Int J Radiat Oncol Biol Phys · April 1, 2019 Featured Publication PURPOSE: To demonstrate proof of principle of visualizing delivered 3-dimensional (3D) dose distribution using kilovoltage (kv) cone beam computed tomography (CBCT) mounted onboard a linear accelerator. We apply this technique as a unique end-to-end verifi ... Full text Link to item Cite

Executive summary of AAPM Report Task Group 113: Guidance for the physics aspects of clinical trials.

Journal Article J Appl Clin Med Phys · September 2018 Featured Publication The charge of AAPM Task Group 113 is to provide guidance for the physics aspects of clinical trials to minimize variability in planning and dose delivery for external beam trials involving photons and electrons. Several studies have demonstrated the import ... Full text Link to item Cite

Development and Preliminary Evaluation of a Murine Model of Chronic Radiation-Induced Proctitis.

Journal Article Int J Radiat Oncol Biol Phys · August 1, 2018 PURPOSE: Radiotherapy (RT) is commonly used to treat most pelvic malignancies. While treatment is often effective, curative radiation doses to the rectum can result in chronic radiation-induced proctitis, which is characterized by diarrhea, tenesmus, and/o ... Full text Link to item Cite

Technical Note: On maximizing Cherenkov emissions from medical linear accelerators.

Journal Article Med Phys · July 2018 PURPOSE: Cherenkov light during MV radiotherapy has recently found imaging and therapeutic applications but is challenged by relatively low fluence. Our purpose is to investigate the feasibility of increasing Cherenkov light production during MV radiothera ... Full text Link to item Cite

In Reply to Pratx and Kapp.

Journal Article Int J Radiat Oncol Biol Phys · June 1, 2018 Full text Link to item Cite

Enhancing Radiation Therapy Through Cherenkov Light-Activated Phototherapy.

Journal Article Int J Radiat Oncol Biol Phys · March 1, 2018 PURPOSE: This work investigates a new approach to enhance radiotherapy through a photo therapeutic agent activated by Cherenkov light produced from the megavoltage photon beam. The process is termed Radiotherapy Enhanced with Cherenkov photo-Activation (RE ... Full text Open Access Link to item Cite

A precision 3D conformal treatment technique in rats: Application to whole-brain radiotherapy with hippocampal avoidance.

Journal Article Med Phys · November 2017 PURPOSE: To develop and validate three-dimensional (3D) conformal hippocampal sparing whole-brain radiation therapy (HA-WBRT) for Wistar rats utilizing precision 3D-printed immobilization and micro-blocks. This technique paves the way for future preclinica ... Full text Link to item Cite

Development of a 3D remote dosimetry protocol compatible with MRgIMRT.

Journal Article Med Phys · November 2017 Featured Publication PURPOSE: To develop a novel remote 3D dosimetry protocol to verify Magnetic Resonance-guided Radiation Therapy (MRgRT) treatments. The protocol was applied to investigate the accuracy of TG-119 IMRT irradiations delivered by the MRIdian® system (ViewRay® , ... Full text Link to item Cite

Enhancing Radiation Therapy Through Cherenkov Light-Activated Phototherapy from Clinical Megavoltage Treatment Beams

Conference International Journal of Radiation Oncology*Biology*Physics · October 2017 Full text Cite

Noninvasive measurement of tissue blood oxygenation with Cerenkov imaging during therapeutic radiation delivery.

Journal Article Opt Lett · August 15, 2017 Tumor tissue oxygenation significantly affects the outcome of radiotherapy. Real-time monitoring of tumor hypoxia is highly desirable for effective radiotherapy, and is the basis for improved treatment because hypoxic tumor cells are more resistant to radi ... Full text Open Access Link to item Cite

A prototype optical-CT system for PRESAGE 3D dosimeter readout

Conference Journal of Physics: Conference Series · June 5, 2017 This work introduces the Duke Integrated-lens Optical Scanner (DIOS), a prototype optical-CT system designed for convenient and low-cost readout of PRESAGE 3D dosimeters. A key novelty of the DIOS is the incorporation of a multi-purpose light-collimating t ... Full text Cite

Characterization of novel preclinical dose distributions for micro irradiator

Conference Journal of Physics: Conference Series · June 5, 2017 This work explores and demonstrates the feasibility of utilizing new 3D printing techniques to implement advanced micro radiation therapy for pre-clinical small animal studies. 3D printed blocks and compensators were designed and printed from a strong x-ra ... Full text Cite

Treatment planning and 3D dose verification of whole brain radiation therapy with hippocampal avoidance in rats

Conference Journal of Physics: Conference Series · June 5, 2017 Despite increasing use of stereotactic radiosurgery, whole brain radiotherapy (WBRT) continues to have a therapeutic role in a selected subset of patients. Selectively avoiding the hippocampus during such treatment (HA-WBRT) emerged as a strategy to reduce ... Full text Cite

How feasible is remote 3D dosimetry for MR guided Radiation Therapy (MRgRT)?

Conference Journal of Physics: Conference Series · June 5, 2017 To develop and apply a remote dosimetry protocol with PRESAGE® radiochromic plastic and optical-CT readout in the validation of MRI guided radiation therapy (MRgRT) treatments (MRIdian® by ViewRay®). Through multi-institutional collaboration we performed P ... Full text Cite

Innovation and the future of advanced dosimetry: 2D to 5D

Conference Journal of Physics: Conference Series · June 5, 2017 Recent years have witnessed a remarkable evolution in the techniques, capabilities and applications of 3D dosimetry. Initially the goal was simple: to innovate new techniques capable of comprehensively measuring and verifying exquisitely intricate dose dis ... Full text Cite

Utilizing a diagnostic kV imaging system for x-ray psoralen activated cancer therapy (X-PACT)

Journal Article Biomedical Physics and Engineering Express · May 25, 2017 X-ray psoralen activated cancer therapy (X-PACT) is a new therapeutic approach that has been shown to induce tumor cell apoptosis and cytotoxicity in vitro, and slow tumor growth in BALB/c mice with syngeneic 4T1 tumors. X-PACT is accomplished by injection ... Full text Cite

Three-Dimensional Dosimetric Validation of a Magnetic Resonance Guided Intensity Modulated Radiation Therapy System.

Journal Article Int J Radiat Oncol Biol Phys · April 1, 2017 PURPOSE: To validate the dosimetric accuracy of a commercially available magnetic resonance guided intensity modulated radiation therapy (MRgIMRT) system using a hybrid approach: 3-dimensional (3D) measurements and Monte Carlo calculations. METHODS AND MAT ... Full text Link to item Cite

Radiochromic 3D Detectors

Chapter · January 1, 2017 This chapter focuses on the development and the state-of-the-art of a suite of full-three dimensional (3D) dosimetry techniques that can provide a more comprehensive solution to the problem of verification of complex radiation therapy (RT) treatments and 3 ... Full text Cite

TH-CD-BRA-02: 3D Remote Dosimetry for MRI-Guided Radiation Therapy: A Hybrid Approach.

Journal Article Med Phys · June 2016 PURPOSE: To validate the dosimetric accuracy of a commercially available MR-IGRT system using a combination of 3D dosimetry measurements (with PRESAGE(R) radiochromic plastic and optical-CT readout) and an in-house developed GPU-accelerated PENELOPE Monte- ... Full text Link to item Cite

TH-CD-BRA-11: Implementation and Evaluation of a New 3D Dosimetry Protocol for Validating MRI Guided Radiation Therapy Treatments.

Journal Article Med Phys · June 2016 PURPOSE: To develop, evaluate and apply a novel high-resolution 3D remote dosimetry protocol for validation of MRI guided radiation therapy treatments (MRIdian by ViewRay™). We demonstrate the first application of the protocol (including two small but requ ... Full text Link to item Cite

SU-F-T-10: Validation of ELP Dosimetry Using PRESAGE Dosimeter: Feasibility Test and Practical Considerations.

Conference Med Phys · June 2016 PURPOSE: To validate the use of a PRESAGE dosimeter as a method to quantitatively measure dose distributions of injectable brachytherapy based on elastin-like polypeptide (ELP) nanoparticles. PRESAGE is a solid, transparent polyurethane-based dosimeter who ... Full text Link to item Cite

WE-FG-BRA-01: Cancer Treatment Utilizing Photo-Activation of Psoralen with KV X-Rays.

Journal Article Med Phys · June 2016 PURPOSE: This work investigates X-PACT (X-ray Psoralen Activated Cancer Therapy): a new approach for the treatment of cancer. X-PACT utilizes psoralen, a potent anti-cancer therapeutic with immunogenic anti-cancer potential. Psoralen therapies have been li ... Full text Link to item Cite

TU-FG-BRC-04: Opportunities for Medical Physics Contributions to Radiation Immunotherapy.

Journal Article Med Phys · June 2016 There is substantial current interest in the potential of radiation therapy for synergizing with novel immunotherapies to transform irradiated tumor into an immunogenic hub with capacity to ignite a powerful and adaptive longterm anti-cancer response. Inte ... Full text Link to item Cite

MO-DE-BRA-02: SIMAC: A Simulation Tool for Teaching Linear Accelerator Physics.

Journal Article Med Phys · June 2016 PURPOSE: The first goal of this work is to develop software that can simulate the physics of linear accelerators (linac). The second goal is to show that this simulation tool is effective in teaching linac physics to medical physicists and linac service en ... Full text Link to item Cite

SU-C-204-06: Monte Carlo Dose Calculation for Kilovoltage X-Ray-Psoralen Activated Cancer Therapy (X-PACT): Preliminary Results.

Journal Article Med Phys · June 2016 PURPOSE: X-PACT is an experimental cancer therapy where kV x-rays are used to photo-activate anti-cancer therapeutics through phosphor intermediaries (phosphors that absorb x-rays and re-radiate as UV light). Clinical trials in pet dogs are currently under ... Full text Link to item Cite

TH-CD-201-05: Characterization of a Novel Light-Collimating Tank Optical-CT System for 3D Dosimetry.

Journal Article Med Phys · June 2016 PURPOSE: Comprehensive 3D dosimetry is highly desirable for advanced clinical QA, but costly optical readout techniques have hindered widespread implementation. Here, we present the first results from a cost-effective Integrated-lens Dry-tank Optical Scann ... Full text Link to item Cite

SU-F-T-507: Modeling Cerenkov Emissions From Medical Linear Accelerators: A Monte Carlo Study.

Journal Article Med Phys · June 2016 PURPOSE: Cerenkov emissions are a natural byproduct of MV radiotherapy but are typically ignored as inconsequential. However, Cerenkov photons may be useful for activation of drugs such as psoralen. Here, we investigate Cerenkov radiation from common radio ... Full text Link to item Cite

TH-EF-207A-06: High-Resolution Optical-CT/ECT Imaging of Unstained Mice Femur, Brain, Spleen, and Tumor.

Journal Article Med Phys · June 2016 PURPOSE: Optical transmission and emission computed tomography (optical-CT/ECT) provides high-resolution 3D attenuation and emission maps in unsectioned large (∼1cm(3) ) ex vivo tissue samples at a resolution of 12.9µm(3) per voxel. Here we apply optical-C ... Full text Link to item Cite

SU-G-IeP4-08: Initial Investigations of Up-Converting Nanoparticles (UCNP) for 3D Tissue Imaging in Optical-ECT.

Journal Article Med Phys · June 2016 PURPOSE: Near-IR absorptive up-converting nanoparticles (UCNPs) is a novel contrast for optical-ECT that allows auto-fluorescence-free 3D imaging of labeled cells in a matrix of large (∼1cm(3) ) unsectioned normal tissue. This has the potential to image sm ... Full text Link to item Cite

TU-FG-BRC-00: Radiation and Immunotherapy: How to Ignite Long Term Anti-Cancer Response.

Journal Article Med Phys · June 2016 There is substantial current interest in the potential of radiation therapy for synergizing with novel immunotherapies to transform irradiated tumor into an immunogenic hub with capacity to ignite a powerful and adaptive longterm anti-cancer response. Inte ... Full text Link to item Cite

WE-AB-BRB-02: Methods and Applications of 3D Radiochromic Dosimetry.

Journal Article Med Phys · June 2016 Despite widespread IMRT treatments at modern radiation therapy clinics, precise dosimetric commissioning of an IMRT system remains a challenge. In the most recent report from the Radiological Physics Center (RPC), nearly 20% of institutions failed an end-t ... Full text Link to item Cite

Optical-CT 3D Dosimetry Using Fresnel Lenses with Minimal Refractive-Index Matching Fluid.

Journal Article PLoS One · 2016 Telecentric optical computed tomography (optical-CT) is a state-of-the-art method for visualizing and quantifying 3-dimensional dose distributions in radiochromic dosimeters. In this work a prototype telecentric system (DFOS-Duke Fresnel Optical-CT Scanner ... Full text Open Access Link to item Cite

X-Ray Psoralen Activated Cancer Therapy (X-PACT).

Journal Article PLoS One · 2016 This work investigates X-PACT (X-ray Psoralen Activated Cancer Therapy): a new approach for the treatment of solid cancer. X-PACT utilizes psoralen, a potent anti-cancer therapeutic with current application to proliferative disease and extracorporeal photo ... Full text Open Access Link to item Cite

WE-EF-BRA-11: Precision Partial-Tumor Irradiation of Dorsal Rodent Mammary Tumors.

Journal Article Med Phys · June 2015 PURPOSE: To introduce a pre-clinical treatment technique on a micro-irradiator to treat specific volumes of dorsal mammary tumors in BALB/c mice while sparing lungs and spine. This technique facilitates pre-clinical investigation of tumor response to sub-o ... Full text Link to item Cite

TH-AB-204-02: Preliminary Study of Up-Converting Nanocrystal (UCNC) Imaging in Optical-ECT.

Journal Article Med Phys · June 2015 PURPOSE: Optical-emission computed tomography (optical- ECT) enables high-resolution 3D imaging of emission in optically cleared tissues on the order of 1 cm(3). This work demonstrates capabilities of optical-ECT to quantify the red fluorescent protein (RF ... Full text Link to item Cite

SU-E-T-353: Effects of Time and Temperature On a Potential Reusable 3D Dosimeter.

Journal Article Med Phys · June 2015 PURPOSE: Preliminary studies of a novel, optically-clearing PRESAGE 3D dosimeter formulation (Presage-RU) demonstrated potential reusability. This study investigates the effects of time and temperature on the accuracy and reusability of Presage-RU, and rep ... Full text Link to item Cite

SU-E-T-675: Remote Dosimetry with a Novel PRESAGE Formulation.

Journal Article Med Phys · June 2015 PURPOSE: 3D-gel dosimetry provides high-resolution treatment validation; however, scanners aren't widely available. In remote dosimetry, dosimeters are shipped out from a central base institution to a remote site for irradiation, then shipped back for scan ... Full text Link to item Cite

SU-E-T-341: DVH-Based Comparison of True 3D Measurements to a Delta4 System.

Conference Med Phys · June 2015 PURPOSE: Delta4 dosimetric software can be used to calculate DVH-based metrics for patient-specific quality assurance from measurements made by a Delta4 QA device. This study investigates the effectiveness of a novel transform method that transposes measur ... Full text Link to item Cite

SU-D-213-05: Design, Evaluation and First Applications of a Off-Site State-Of-The-Art 3D Dosimetry System.

Journal Article Med Phys · June 2015 PURPOSE: To design, construct and commission a prototype in-house three dimensional (3D) dose verification system for stereotatic body radiotherapy (SBRT) verification at an off-site partner institution. To investigate the potential of this system to achie ... Full text Link to item Cite

SU-E-T-93: Activation of Psoralen at Depth Using Kilovoltage X-Rays: Physics Considerations in Implementing a New Teletherapy Paradigm.

Journal Article Med Phys · June 2015 PURPOSE: Psoralen is a UV-light activated anti-cancer biotherapeutic used for treating skin lesions (PUVA) and advanced cutaneous T-cell lymphoma (ECP). To date psoralen has not been used to treat deep seated tumors due to difficulty in generating UV-light ... Full text Link to item Cite

Investigations into the feasibility of optical-CT 3D dosimetry with minimal use of refractively matched fluids.

Journal Article Med Phys · May 2015 PURPOSE: In optical-CT, the use of a refractively matched polyurethane solid-tank in place of a fluid bath has the potential to greatly increase practical convenience, reduce cost, and possibly improve the efficacy of flood corrections. This work investiga ... Full text Link to item Cite

An investigation of PRESAGE® 3D dosimetry for IMRT and VMAT radiation therapy treatment verification.

Journal Article Phys Med Biol · March 21, 2015 The purpose of this work was to characterize three formulations of PRESAGE(®) dosimeters (DEA-1, DEA-2, and DX) and to identify optimal readout timing and procedures for accurate in-house 3D dosimetry. The optimal formulation and procedure was then applied ... Full text Link to item Cite

Investigating the accuracy of microstereotactic-body-radiotherapy utilizing anatomically accurate 3D printed rodent-morphic dosimeters.

Journal Article Med Phys · February 2015 PURPOSE: Sophisticated small animal irradiators, incorporating cone-beam-CT image-guidance, have recently been developed which enable exploration of the efficacy of advanced radiation treatments in the preclinical setting. Microstereotactic-body-radiation- ... Full text Link to item Cite

Utility and validation of biomechanical deformable image registration in low-contrast images.

Journal Article Pract Radiat Oncol · 2015 PURPOSE: The application of a biomechanical deformable image registration algorithm has been demonstrated to overcome the potential limitations in the use of intensity-based algorithms on low-contrast images that lack prominent features. Because validation ... Full text Link to item Cite

Verification of micro-beam irradiation

Conference Journal of Physics: Conference Series · January 1, 2015 Micro-beam Radiation Therapy (MRT) is an experimental radiation therapy with provocative experimental data indicating potential for improved efficacy in some diseases. Here we demonstrated a comprehensive micro-beam verification method utilizing high resol ... Full text Cite

Radiochromic 3D Detectors

Conference Journal of Physics: Conference Series · January 1, 2015 Radiochromic materials exhibit a colour change when exposed to ionising radiation. Radiochromic film has been used for clinical dosimetry for many years and increasingly so recently, as films of higher sensitivities have become available. The two principle ... Full text Cite

Characterization of a reusable PRESAGE® 3D dosimeter

Conference Journal of Physics: Conference Series · January 1, 2015 This study investigates a reusable PRESAGE® 3D dosimeter (Presage-RU), which would improve cost-effectiveness and facilitate wider implementation of comprehensive, high resolution 3D dosimetry. Small (1x1x4.5 cm) and large (8 cm diameter, 4.5 cm length) sa ... Full text Cite

Investigation of a low-cost optical-CT system with minimal refractive index-matching fluid

Conference Journal of Physics: Conference Series · January 1, 2015 Optical computed tomography (optical-CT) is a method for visualizing 3dimensional dose distributions in radiochromic dosimeters. Projection images are acquired by collimating a visible light point source into parallel-beam geometry and imaging differential ... Full text Cite

Treatment Planning and Delivery of Whole Brain Irradiation with Hippocampal Avoidance in Rats.

Journal Article PLoS One · 2015 BACKGROUND: Despite the clinical benefit of whole brain radiotherapy (WBRT), patients and physicians are concerned by the long-term impact on cognitive functioning. Many studies investigating the molecular and cellular impact of WBRT have used rodent model ... Full text Link to item Cite

Deformable Dose Reconstruction With Biomechanical Registration: Validation in Low-Contrast Images

Conference International Journal of Radiation Oncology*Biology*Physics · September 2014 Full text Cite

An investigation of a PRESAGE® in vivo dosimeter for brachytherapy.

Journal Article Phys Med Biol · July 21, 2014 Determining accurate in vivo dosimetry in brachytherapy treatment with high dose gradients is challenging. Here we introduce, investigate, and characterize a novel in vivo dosimeter and readout technique with the potential to address this problem. A cylind ... Full text Link to item Cite

On the feasibility of comprehensive high-resolution 3D remote dosimetry.

Journal Article Med Phys · July 2014 PURPOSE: This study investigates the feasibility of remote high-resolution 3D dosimetry with the PRESAGE®/Optical-CT system. In remote dosimetry, dosimeters are shipped out from a central base institution to a remote institution for irradiation, then shipp ... 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

TH-C-BRF-01: The Promise and Potential Pitfalls of Deformable Image Registration in Clinical Practice.

Journal Article Med Phys · June 2014 Accurate and robust deformable image registration (DIR) is a key enabling technique in the clinical realization of two approaches for advancing radiation therapy treatment efficacy: adaptive radiation therapy and treatment response assessment. Currently th ... Full text Link to item Cite

SU-C-BRE-04: Microbeam-Radiation-Therapy (MRT): Characterizing a Novel MRT Device Using High Resolution 3D Dosimetry.

Journal Article Med Phys · June 2014 PURPOSE: The feasibility of MRT has recently been demonstrated utilizing a new technology of Carbon-Nano-Tube(CNT) field emission x-ray sources. This approach can deliver very high dose(10's of Gy) in narrow stripes(sub-mm) of radiation which enables the s ... Full text Link to item Cite

SU-E-T-294: Simulations to Investigate the Feasibility of 'dry' Optical-CT Imaging for 3D Dosimetry.

Journal Article Med Phys · June 2014 PURPOSE: To perform simulations investigating the feasibility of "dry" optical-CT, and determine optimal design and scanning parameters for a novel dry tank telecentric optical-CT 3D dosimetry system. Such a system would have important advantages in terms ... Full text Link to item Cite

SU-F-BRF-13: Investigating the Feasibility of Accurate Dose Measurement in a Deforming Radiochromic Dosimeter.

Journal Article Med Phys · June 2014 PURPOSE: Presage-Def, a deformable radiochromic 3D dosimeter, has been previously shown to have potential for validating deformable image registration algorithms. This work extends this effort to investigate the feasibility of using Presage-Def to validate ... Full text Link to item Cite

WE-F-16A-04: Micro-Irradiator Treatment Verification with High-Resolution 3D-Printed Rodent-Morphic Dosimeters.

Journal Article Med Phys · June 2014 PURPOSE: Pre-clinical micro-radiation therapy studies often utilize very small beams (∼0.5-5mm), and require accurate dose delivery in order to effectively investigate treatment efficacy. Here we present a novel high-resolution absolute 3D dosimetry proced ... Full text Link to item Cite

SU-A-BRF-01: Education Council Symposium: Online Education in Medical Physics.

Journal Article Med Phys · June 2014 Online education is rapidly becoming an important means of communicating content in educational activities across a broad spectrum of fields, including medical physics. We are currently at a point of broad change in educational strategies and methodologies ... Full text Link to item Cite

SU-E-J-164: An Investigation of a Low-Cost 'dry' Optical-CT Scanning System for 3D Dosimetry.

Journal Article Med Phys · June 2014 PURPOSE: To characterize and explore the efficacy of a novel low-cost, lowfluid, broad-beam optical-CT system for 3D-dosimetry in radiochromic Presage dosimeters. Leading current optical-CT systems incorporate expensive glass-based telecentric lens technol ... Full text Link to item Cite

TU-C-BRE-05: Clinical Implications of AAA Commissioning Errors and Ability of Common Commissioning ' Credentialing Procedures to Detect Them.

Journal Article Med Phys · June 2014 PURPOSE: To test the ability of the TG-119 commissioning process and RPC credentialing to detect errors in the commissioning process for a commercial Treatment Planning System (TPS). METHODS: We introduced commissioning errors into the commissioning proces ... Full text Link to item Cite

SU-E-J-80: Interplay Effect Between VMAT Intensity Modulation and Tumor Motion in Hypofractioned Lung Treatment, Investigated with 3D Pressage Dosimeter.

Journal Article Med Phys · June 2014 PURPOSE: To demonstrate an embedded tissue equivalent presage dosimeter for measuring 3D doses in moving tumors and to study the interplay effect between the tumor motion and intensity modulation in hypofractioned Volumetric Modulated Arc Therapy(VMAT) lun ... Full text Link to item Cite

TH-C-19A-05: Evaluation of a New Reusable 3D Dosimeter.

Journal Article Med Phys · June 2014 PURPOSE: PRESAGE is a radiochromic plastic which has demonstrated strong potential for high resolution single-use 3D dosimetry. This study evaluates a new PRESAGE formulation (Presage-RU) in which the radiochromic response is reversible (the dosimeter opti ... Full text Link to item Cite

SU-E-T-472: A Multi-Dimensional Measurements Comparison to Analyze a 3D Patient Specific QA Tool.

Conference Med Phys · June 2014 PURPOSE: To quantitatively evaluate a 3D patient specific QA tool using 2D film and 3D Presage dosimetry. METHODS: A brain IMRT case was delivered to Delta4, EBT2 film and Presage plastic dosimeter. The film was inserted in the solid water slabs at 7.5cm d ... Full text Link to item Cite

Evaluation of a New Reusable 3D Dosimeter

Conference MEDICAL PHYSICS · June 1, 2014 Link to item Cite

ALS-associated mutation FUS-R521C causes DNA damage and RNA splicing defects.

Journal Article J Clin Invest · March 2014 Autosomal dominant mutations of the RNA/DNA binding protein FUS are linked to familial amyotrophic lateral sclerosis (FALS); however, it is not clear how FUS mutations cause neurodegeneration. Using transgenic mice expressing a common FALS-associated FUS m ... Full text Link to item Cite

A comprehensive investigation of the accuracy and reproducibility of a multitarget single isocenter VMAT radiosurgery technique.

Journal Article Med Phys · December 2013 PURPOSE: Recent trends in stereotactic radiosurgery use multifocal volumetric modulated arc therapy (VMAT) plans to simultaneously treat several distinct targets. Conventional verification often involves low resolution measurements in a single plane, a cyl ... Full text Link to item Cite

Investigating end-to-end accuracy of image guided radiation treatment delivery using a micro-irradiator.

Journal Article Phys Med Biol · November 7, 2013 There is significant interest in delivering precisely targeted small-volume radiation treatments, in the pre-clinical setting, to study dose-volume relationships with tumour control and normal tissue damage. For these studies it is vital that image guidanc ... Full text Link to item Cite

On the need for comprehensive validation of deformable image registration, investigated with a novel 3-dimensional deformable dosimeter.

Journal Article Int J Radiat Oncol Biol Phys · October 1, 2013 PURPOSE: To introduce and evaluate a novel deformable 3-dimensional (3D) dosimetry system (Presage-Def/Optical-CT) and its application toward investigating the accuracy of dose deformation in a commercial deformable image registration (DIR) package. METHOD ... Full text Link to item Cite

SU-D-108-03: Evaluation of the Feasibility of a Novel Radiochromic Dosimetry System for In-Vivo Dose Verification in Organs at Risk in HDR Intracavitary Gynecological Brachytherapy.

Journal Article Med Phys · June 2013 PURPOSE: To evaluate the feasibility of a novel radiochromic dosimetry system for in-vivo dose verification in organs at risk in HDR intracavitary gynecological brachytherapy. METHODS: Novel, small cylindrical PRESAGE dosimeters (4mm in diameter by 20mm in ... Full text Link to item Cite

SU-E-T-353: Feasibility of 3D Dosimetry for Prostate LDR: Monte Carlo Simulations of Pd-103,I-125, and Cs-131 Seeds in Deformable PRESAGE.

Journal Article Med Phys · June 2013 PURPOSE: Recent innovations in 3D dosimetry include deformable polyurethane dosimeters (PRESAGE) and high resolution optical CT (∼50 microns). These developments enable 3D dosimetry in deformation conditions present during prostate LDR brachytherapy. Howev ... Full text Link to item Cite

WE-E-108-09: An Investigation of the Feasibility of Rodentmorphic 3D Dosimeters for Verification of Precision Micro-Irradiator Treatment.

Journal Article Med Phys · June 2013 PURPOSE: To evaluate the feasibility of novel rodentmorphic 3D dosimeters for comprehensive high-resolution verification of the treatment accuracy of a state-of-the-art micro-irradiator equipped with on-line cone-beam-CT guidance. METHODS: Anatomically acc ... Full text Link to item Cite

SU-E-T-53: An Investigation of the Dosimetric Characteristics of a Novel Radiochromic 3D Dosimeter.

Journal Article Med Phys · June 2013 PURPOSE: A new formulation of PRESAGE has been developed with potential for increased dose sensitivity and post irradiation temporal stability. DEA-PRESAGE differs from conventional PRESAGE by incorporating a methoxy group adjacent to the methine and N,N d ... Full text Link to item Cite

SU-D-144-07: Preliminary Characterization of Microbeam Radiation Using Very High Resolution 3D Dosimetry.

Journal Article Med Phys · June 2013 PURPOSE: Compact microbeam radiation therapy (MRT) recently became feasible through the development of carbon-nanotube based distributed x-ray array technology. This work investigates the feasibility of novel highresolution 3D dosimetry techniques (50μm is ... Full text Link to item Cite

SU-E-T-40: Is Accurate 3D Dosimetry Possible When Using Optical-CT Readout with Low (or Without) Refractive Index Matching Fluids?

Journal Article Med Phys · June 2013 PURPOSE: Achieving accurate optical-CT 3D dosimetry without the use of viscous refractive index (RI) matching fluids would greatly increase convenience. This work evaluates various potential 'dry-scan' optical-CT configurations (including parallel, point, ... Full text Link to item Cite

MO-F-108-11: 3D Verification for Multifocal Single Isocenter SRS.

Journal Article Med Phys · June 2013 PURPOSE: Recent trends in SRS use multifocal VMAT plans to simultaneously treat several, distinct targets. Conventional verification often involves low resolution measurements in a single plane, cylinder, or intersecting planes of diodes or ion chambers. T ... Full text Link to item Cite

MO-D-141-09: An Investigation of the Feasibility of Volumetric Imaging of Fluorescent Bio-Markers Using Optical-ECT.

Journal Article Med Phys · June 2013 PURPOSE: Toptical-ECT is a technique with potential for high resolution 3D imaging of the distribution of fluoresent biomarkers (including reporter proteins like GFP) in un-sectioned tissue samples. Accurate optical-ECT data is only feasible if the biomark ... Full text Link to item Cite

SU-C-105-03: Progress Toward the Development of a Deformable Anthropomorphic 3D Dosimetric Phantom.

Journal Article Med Phys · June 2013 PURPOSE: Previous work has demonstrated that Presage-Def, a deformable, polyurethane-based radiochromic 3D dosimeter, has strong potential for validating deformable image registration algorithms by tracking optically measured radiation patterns from the de ... Full text Link to item Cite

On the feasibility of optical-CT imaging in media of different refractive index.

Journal Article Med Phys · May 2013 PURPOSE: Achieving accurate optical-CT 3D dosimetry without the use of viscous refractive index (RI) matching fluids would greatly increase convenience. METHODS: Software has been developed to simulate optical-CT 3D dosimetry for a range of scanning config ... Full text Link to item Cite

Towards comprehensive characterization of Cs-137 Seeds using PRESAGE® dosimetry with optical tomography.

Conference J Phys Conf Ser · 2013 We describe a method to directly measure the radial dose and anisotropy functions of brachytherapy sources using polyurethane based dosimeters read out with optical CT. We measured the radial dose and anisotropy functions for a Cs-137 source using a PRESAG ... Full text Link to item Cite

Comprehensive quality assurance for base of skull IMRT.

Conference J Phys Conf Ser · 2013 Six base of skull IMRT treatment plans were delivered to Presage dosimeters within the RPC Head and Neck Phantom for quality assurance (QA) verification. Isotropic 2mm 3D data were acquired by optical-CT scanning with the DLOS system (Duke Large Optical-CT ... Full text Link to item Cite

Preliminary investigation and application of a novel deformable PRESAGE® dosimeter.

Conference J Phys Conf Ser · 2013 Deformable 3D dosimeters have potential applications in validating deformable dose mapping algorithms. This study evaluates a novel deformable PRESAGE® dosimeter and its application toward validating the deformable algorithm employed by VelocityAI. The def ... Full text Link to item Cite

Customising PRESAGE® for diverse applications.

Conference J Phys Conf Ser · 2013 PRESAGE® is a solid radiochromic dosimeter consisting of a polyurethane matrix, a triarylmethane leuco dye, and a trihalomethane initiator. Varying the composition and/or relative amounts of these constituents can affect the dose sensitivity, post-irradiat ... Full text Link to item Cite

Evaluation of a clinically intuitive quality assurance method.

Conference J Phys Conf Ser · 2013 There is a pressing need for clinically intuitive quality assurance methods that report metrics of relevance to the likely impact on tumor control of normal tissue injury. This paper presents a preliminary investigation into the accuracy of a novel "transf ... Full text Link to item Cite

How accurate is image guided radiation therapy (IGRT) delivered with a micro-irradiator?

Conference J Phys Conf Ser · 2013 There is significant interest in delivering precisely targeted small-volume radiation treatments, in the pre-clinical setting, to study dose-volume relationships with tumor control and normal tissue damage. In this work we investigate the IGRT targeting ac ... Full text Link to item Cite

The effect of motion on IMRT - looking at interplay with 3D measurements.

Conference J Phys Conf Ser · 2013 Six base of skull IMRT treatment plans were delivered to 3D dosimeters within the RPC Head and Neck Phantom for QA verification. Isotropic 2mm 3D data was obtained using the DLOS-PRESAGE system and compared to an Eclipse (Varian) treatment plan. Normalized ... Full text Link to item Cite

Investigating the reproducibility of a complex multifocal radiosurgery treatment.

Conference J Phys Conf Ser · 2013 Stereotactic radiosurgery has become a widely used technique to treat solid tumors and secondary metastases of the brain. Multiple targets can be simultaneously treated with a single isocenter in order to reduce the set-up time to improve patient comfort a ... Full text Link to item Cite

Journal of Physics: Conference Series - Preface

Journal Article Journal of Physics: Conference Series · January 1, 2013 Full text Cite

Feasibility of using PRESAGE® for relative 3D dosimetry of small proton fields.

Journal Article Phys Med Biol · November 21, 2012 Small field dosimetry is challenging due to the finite size of the conventional detectors that underestimate the dose distribution. With the fast development of the dynamic proton beam delivery system, it is essential to find a dosimeter which can be used ... Full text Link to item Cite

A quality assurance method that utilizes 3D dosimetry and facilitates clinical interpretation.

Journal Article Int J Radiat Oncol Biol Phys · October 1, 2012 PURPOSE: To demonstrate a new three-dimensional (3D) quality assurance (QA) method that provides comprehensive dosimetry verification and facilitates evaluation of the clinical significance of QA data acquired in a phantom. Also to apply the method to inve ... Full text Link to item Cite

Commissioning a CT-compatible LDR tandem and ovoid applicator using Monte Carlo calculation and 3D dosimetry.

Journal Article Med Phys · July 2012 PURPOSE: To determine the geometric and dose attenuation characteristics of a new commercially available CT-compatible LDR tandem and ovoid (T&O) applicator using Monte Carlo calculation and 3D dosimetry. METHODS: For geometric characterization, we quantif ... Full text Link to item Cite

Submerged RadBall® deployments in Hanford Site hot cells containing 137CsCl capsules.

Journal Article Health Phys · July 2012 The overall objective of this study was to demonstrate that a new technology, known as RadBall®, could locate submerged radiological hazards. RadBall® is a novel, passive, radiation detection device that provides a 3-D visualization of radiation from areas ... Full text Link to item Cite

SU-D-213AB-05: Commissioning a CT Compatible LDR T&O Applicator Using Analytical Calculation with ID and 3D Dosimetry.

Journal Article Med Phys · June 2012 PURPOSE: To determine the characteristics of a new commercially available CT-compatible LDR Tandem and Ovoid (T&O) applicator using 3D dosimetry. METHODS: We characterized source attenuation through the asymmetric gold shielding in the buckets by measuring ... Full text Link to item Cite

TU-E-BRB-09: Validation of Multi-Focal Stereotactic Radiosurgery with Volumetric Modulated Arc Therapy with High-Resolution 3D Dosimetry.

Journal Article Med Phys · June 2012 PURPOSE: Volumetric modulated arc therapy (VMAT) enables stereotactic radiosurgery (SRS) treatment for multiple lesions with a single isocenter setup. Dosimetry verification is highly challenging however, and the purpose of this study is to validate this n ... Full text Link to item Cite

WE-E-BRB-04: Quantitative Dose Tracking Enabled Through a Novel Deformable 3D Dosimeter.

Journal Article Med Phys · June 2012 PURPOSE: To evaluate and investigate the feasibility of a new method for validating dose tracking algorithms in deforming tissues using a novel deformable 3D dosimeter. METHODS: A novel deformable 3D Presage dosimeter is reported consisting of a stretchy p ... Full text Link to item Cite

SU-E-T-108: 3D Measurement of Neutron Dose from a Novel Neutron Imaging Technique.

Journal Article Med Phys · June 2012 PURPOSE: We have been developing a fast-neutron spectroscopic technique to quantitatively image the distribution of elements in the body using quasi-monochromatic neutron beams. Previously, we demonstrated the ability of the technique to quantify specific ... Full text Link to item Cite

SU-E-T-93: High Dynamic Range Scanning for Optical-CT in 3D Dosimetry.

Journal Article Med Phys · June 2012 PURPOSE: The recent emergence of powerful, fast and high-resolution 3D dosimetry techniques brings exciting potential to radically strengthen the foundations of quality-assurance in radiation therapy, and hence treatment efficacy. This work presents a new ... Full text Link to item Cite

Locating, quantifying and characterising radiation hazards in contaminated nuclear facilities using a novel passive non-electrical polymer based radiation imaging device.

Journal Article J Radiol Prot · June 2012 This paper provides a summary of recent trials which took place at the US Department of Energy Oak Ridge National Laboratory (ORNL) during December 2010. The overall objective for the trials was to demonstrate that a newly developed technology could be use ... Full text Link to item Cite

Locating radiation hazards and sources within contaminated areas by implementing a reverse ray tracing technique in the RadBall™ technology.

Journal Article Health Phys · February 2012 RadBall™ is a novel technology that can locate unknown radioactive hazards within contaminated areas, hot cells, and gloveboxes. The device consists of a colander-like outer tungsten collimator that houses a radiation-sensitive polymer semisphere. The coll ... Full text Link to item Cite

Commissioning a small-field biological irradiator using point, 2D, and 3D dosimetry techniques.

Journal Article Med Phys · December 2011 PURPOSE: To commission a small-field biological irradiator, the XRad225Cx from Precision x-Ray, Inc., for research use. The system produces a 225 kVp x-ray beam and is equipped with collimating cones that produce both square and circular radiation fields r ... Full text Link to item Cite

Investigation of Proton Beam Dose Distributions with 3D Dosimetry

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

Commissioning and benchmarking a 3D dosimetry system for clinical use.

Journal Article Med Phys · August 2011 PURPOSE: A 3D dosimetry system is described which consists of two parts: a radiochromic plastic dosimeter PRESAGE (which responds to absorbed dose with a linear change in optical-density) and the Duke large-field-of-view optical-CT scanner (DLOS). The DLOS ... Full text Link to item Cite

A method to correct for stray light in telecentric optical-CT imaging of radiochromic dosimeters.

Journal Article Phys Med Biol · July 21, 2011 Radiochromic plastic and gel materials have recently emerged which can yield 3D dose information over clinical volumes in high resolution. These dosimeters can provide a much more comprehensive verification of complex radiation therapy treatments than can ... Full text Link to item Cite

A method to correct for spectral artifacts in optical-CT dosimetry.

Journal Article Phys Med Biol · June 7, 2011 The recent emergence of radiochromic dosimeters with low inherent light-scattering presents the possibility of fast 3D dosimetry using broad-beam optical computed tomography (optical-CT). Current broad beam scanners typically employ either a single or a pl ... Full text Link to item Cite

Dosimetry tools and techniques for IMRT.

Journal Article Med Phys · March 2011 Intensity modulated radiation therapy (IMRT) poses a number of challenges for properly measuring commissioning data and quality assurance (QA) radiation dose distributions. This report provides a comprehensive overview of how dosimeters, phantoms, and dose ... Full text Link to item Cite

MO‐G‐BRB‐02: Commissioning a Small Animal Irradiator Using 2D and 3D Dosimetry Techniques

Conference Medical Physics · January 1, 2011 Purpose: To commission and characterize a novel small animal irradiator, the XRad225cx from Precision X‐Ray Inc. This system is capable of delivering both square and circular fields ranging in size from 1mm to 40mm. The combination of very small field size ... Full text Cite

SU‐E‐T‐133: A Method to Improve the Accuracy of Optical‐CT 3D Dosimetry by Correcting for Stray Light

Conference Medical Physics · January 1, 2011 Purpose: Radiochromic plastics have recently emerged which can yield 3D dose information over clinical volumes in high resolution. These dosimeters require a fast, accurate read‐out, and broad beam optical‐Computed‐Tomography (optical‐CT) systems have show ... Full text Cite

TU‐E‐BRA‐02: How Should We Verify Complex Radiation Therapy Treatments ?

Conference Medical Physics · January 1, 2011 The critical importance of comprehensive treatment verification to patient safety is a topic of major current interest. The increase in complexity of modern treatments has created a direct need for correspondingly more sophisticated and comprehensive verif ... Full text Cite

WE‐E‐BRB‐08: Commissioning and Benchmarking a 3D Dosimetry System for Clinical Use

Conference Medical Physics · January 1, 2011 Purpose: To commission and benchmark a 3D dosimetry system for clinical use, in particular, for verification and commissioning of complex radiation treatments like VMAT, IMRT and gated treatments. The system is composed of two parts: a radiochromic plastic ... Full text Cite

TU‐C‐BRB‐01: A Method to Determine Measured Dose‐Volume‐Histograms (DVH) in Patient from 3D Dose Measurement in Phantom

Conference Medical Physics · January 1, 2011 Purpose: Three‐dimensional (3D) dosimetry systems are rapidly improving, and provide vastly more data and comprehensive QA than can be achieved with conventional dosimetry systems. New challenges emerge including how best to utilize this data. Here we pres ... Full text Cite

SU‐E‐T‐88: 3D Dosimetry for Small Irregular Proton Fields Using a New PRESAGE® Dosimeter

Conference Medical Physics · January 1, 2011 Purpose: Small field dosimetry is challenging that impacts patient specific QA in proton beam therapy due to detector size, aperture scattering and disequilibrium. Therefore, it is urgent to develop an accurate and efficient method to quantify the uncertai ... Full text Cite

SU‐E‐T‐363: Investigation of PRESAGE® Dosimeters for Proton Therapy

Conference Medical Physics · January 1, 2011 Purpose: To evaluate a formulation of PRESAGE® intended for proton therapy and to use it to compare measurements with calculations for a spot scanning pencil proton beam and a passively scattered proton beam.Methods: Two 7.5 cm high by 9.5 cm diameter cyli ... Full text Cite

SU‐E‐T‐99: A Patient Specific QA Protocol for Verification of 4D Dosimetry

Conference Medical Physics · January 1, 2011 Purpose: Presently, there is no patient specific dosimetric QA for radiation treatment of moving targets. Here we present a patient specific QA protocol for verification of 4D dosimetry delivered to a moving target in SBRT of lung and liver tumors. Methods ... Full text Cite

Preliminary Investigation of the Dosimetric Properties of 'RadGel'.

Journal Article J Phys Conf Ser · 2011 A preliminary investigation into the efficacy of a new 3D dosimetry material, RadGel™, for verification of radiation therapy dose distributions is presented. Small volumes of RadGel™ were found to exhibit a linear, reproducible response to dose. A gradual ... Full text Link to item Cite

Initial experience with optical-CT scanning of RadBall Dosimeters.

Journal Article J Phys Conf Ser · December 7, 2010 Featured Publication The RadBall dosimeter is a novel device for providing 3-D information on the magnitude and distribution of contaminant sources of unknown radiation in a given hot cell, glovebox, or contaminated room. The device is presently under evaluation by the Nationa ... Full text Link to item Cite

Dose Verification of Stereotactic Radiosurgery Treatment for Trigeminal Neuralgia with Presage 3D Dosimetry System.

Journal Article J Phys Conf Ser · December 7, 2010 Featured Publication Achieving adequate verification and quality-assurance (QA) for radiosurgery treatment of trigeminal-neuralgia (TGN) is particularly challenging because of the combination of very small fields, very high doses, and complex irradiation geometries (multiple g ... Full text Link to item Cite

Three-Dimensional Dosimetry of a Beta-Emitting Radionuclide Using PRESAGE Dosimeters.

Journal Article J Phys Conf Ser · December 7, 2010 Featured Publication Three-dimensional dose distributions from liquid brachytherapy were measured using PRESAGE(®) dosimeters. The dosimeters were exposed to Y-90 for 5.75 days and read by optical tomography. The distributions are consistent with estimates from beta dose kerne ... Full text Link to item Cite

On the Feasibility of Verification of 3D Dosimetry Near Brachytherapy Sources Using PRESAGE/Optical-CT.

Journal Article J Phys Conf Ser · December 7, 2010 PURPOSE: The feasibility of using the PRESAGE/Optical-CT system for 3D dosimetry verification around a brachytherapy source is investigated. METHOD AND MATERIALS: Brachytherapy dose distributions were obtained by irradiation of cylindrical PRESAGE volumes ... Full text Link to item Cite

RadBall technology testing for hot cell characterization

Journal Article Decommissioning, Decontamination, and Reutilization Topical Meeting 2010, DD and R 2010 · December 1, 2010 Cite

A comprehensive method for optical-emission computed tomography.

Journal Article Phys Med Biol · July 21, 2010 Featured Publication Optical-computed tomography (CT) and optical-emission computed tomography (ECT) are recent techniques with potential for high-resolution multi-faceted 3D imaging of the structure and function in unsectioned tissue samples up to 1-4 cc. Quantitative imaging ... Full text Link to item Cite

Investigation into the feasibility of using PRESAGE/optical-CT dosimetry for the verification of gating treatments.

Journal Article Phys Med Biol · April 21, 2010 Featured Publication This work presents an investigation into the use of PRESAGE dosimeters with an optical-CT scanner as a 3D dosimetry system for quantitative verification of respiratory-gated treatments. The CIRS dynamic thorax phantom was modified to incorporate a moving P ... Full text Link to item Cite

Polymer gel dosimetry.

Journal Article Phys Med Biol · March 7, 2010 Featured Publication Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-d ... Full text Link to item Cite

Toward acquiring comprehensive radiosurgery field commissioning data using the PRESAGE/optical-CT 3D dosimetry system.

Journal Article Phys Med Biol · March 7, 2010 Featured Publication Achieving accurate small field dosimetry is challenging. This study investigates the utility of a radiochromic plastic PRESAGE read with optical-CT for the acquisition of radiosurgery field commissioning data from a Novalis Tx system with a high-definition ... Full text Link to item Cite

TU‐E‐201C‐08: A Comprehensive Method for Optical ‐ Emission Computed Tomography

Conference Medical Physics · January 1, 2010 Purpose: Optical‐CT and optical‐ECT are techniques with unique capability for high‐resolution 3D imaging of structure and function in tissue samples up to 4cc. In particular, 3D vasculature structure and distribution of fluorescent bio‐markers (e.g. green‐ ... Full text Cite

TU‐E‐201C‐06: Imaging the Biological Structure and Characteristics of Model Tumors Using Optical Computed Transmission and Emission Tomography

Conference Medical Physics · January 1, 2010 Purpose: To obtain the first co‐registered high resolution 3D images of an intact xenograft tumor showing (i) the vasculature network labeled with an absorbing vasculature contrast agent, and imaged with optical‐CT (ii) the distribution of red‐fluorescent‐ ... Full text Cite

SU‐GG‐T‐363: 3D Dosimetric Verification of Ir‐192 HDR Brachytherapy Source Irradiation

Conference Medical Physics · January 1, 2010 Purpose: Experimental verification of brachytherapy dose distributions, especially closer than 1 cm from the source, is very difficult with current dosimetry tools. PRESAGE, a 3D radio‐chromic plastic, has already shown promise in the realm of high energy ... Full text Cite

TU‐C‐BRA‐01: Memorial to Lester Skaggs

Conference Medical Physics · January 1, 2010 Memorial to Lester Skaggs. © 2010, American Association of Physicists in Medicine. All rights reserved. ... Full text Cite

SU‐GG‐T‐371: Measurement of Dose to Pacemakers and Other Implantable Medical Devices

Conference Medical Physics · January 1, 2010 Purpose: Radiotherapy can adversely impair the function of implantable devices such as pacemakers and implantable cardioverter‐defibrillators. Tolerable dose limits are manufacturer dependent, complicating protocol standardization for radiotherapy clinics. ... Full text Cite

SU‐GG‐T‐362: Is Distance‐Dependent Energy Correction Needed for Dosimetric Measurements Surrounding Brachytherapy Sources?

Conference Medical Physics · January 1, 2010 Purpose: The answer depends on both the dosimeter's energy response and energy spectrum at distance (point of measurement) from the source. The latter is object of this study. Method and Materials: The spectra in water were calculated with Monte Carlo code ... Full text Cite

Preliminary commissioning investigations with the DMOS-RPC optical-CT Scanner.

Journal Article J Phys Conf Ser · 2010 Featured Publication A midsized broad beam Optical-CT scanner is being developed for collaborative research between Duke and the Radiological Physics Center (RPC). The Duke Midsized Optical-CT Scanner (DMOS-RPC) is designed to be compatible with several of the RPC phantoms, in ... Full text Link to item Cite

An investigation into a new re-useable 3D radiochromic dosimetry material, Presage.

Journal Article J Phys Conf Ser · January 1, 2010 Featured Publication PURPOSE: To investigate the dosimetric properties of a new Presage formulation which exhibits a reversible color change on exposure to radiation. Presage(REU) offers the intriguing possibility of the first re-useable 3D dosimetry material. METHOD AND MATER ... Full text Link to item Cite

Fast, large field-of-view, telecentric optical-CT scanning system for 3D radiochromic dosimetry.

Journal Article J Phys Conf Ser · January 1, 2010 Featured Publication We describe initial experiences with an in-house, fast, large field-of-view optical-CT telecentric scanner (the Duke Large field of view Optical-CT Scanner (DLOS)). The DLOS system is designed to enable telecentric optical-CT imaging of dosimeters up to 24 ... Full text Link to item Cite

Achieving accurate radiochromic optical-CT imaging when using a polychromatic light source.

Journal Article J Phys Conf Ser · 2010 Featured Publication Optical-CT performed with a broad spectrum light source can lead to inaccurate reconstructed attenuation coefficients (and hence dose) due to 'spectral warping' as the beam passes through the dosimeter. Some wavelengths will be attenuated more strongly tha ... Full text Link to item Cite

A 'quad-phantom' film dosimeter for use as a multi-planar verification tool for PRESAGE/optical-CT.

Journal Article J Phys Conf Ser · 2010 Featured Publication INTRODUCTION: To develop and characterize the accuracy and reproducibility of a quad-phantom dosimeter which will serve as an independent verification tool during commissioning of a PRESAGE/optical-CT 3D dosimetry system. METHODS: A 16cm × 12cm cylindrical ... Full text Link to item Cite

RadBall Technology Testing and MCNP Modeling of the Tungsten Collimator.

Journal Article J Phys Conf Ser · 2010 The United Kingdom's National Nuclear Laboratory (NNL) has developed a remote, non-electrical, radiation-mapping device known as RadBall(™), which can locate and quantify radioactive hazards within contaminated areas of the nuclear industry. RadBall(™) con ... Full text Link to item Cite

ScanSim: A tool for simulating optical-CT imaging.

Journal Article J Phys Conf Ser · 2010 A software tool has been developed that can simulate image formation in a variety of optical-CT scanning configurations. The formalism of the simulation is introduced, including two main modes: a diverging point source mode, and a converging broad beam mod ... Full text Link to item Cite

Dosimetry challenges for implementing emerging technologies.

Journal Article J Phys Conf Ser · 2010 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

RadBall Technology Testing in the Savannah River Site's Health Physics Instrument Calibration Laboratory.

Journal Article J Phys Conf Ser · 2010 The United Kingdom's National Nuclear Laboratory (NNL) has developed a radiation-mapping device that can locate and quantify radioactive hazards within contaminated areas of the nuclear industry. The device, known as RadBall(™), consists of a colander-like ... Full text Link to item Cite

Chairman's introduction and welcome message

Journal Article Journal of Physics: Conference Series · January 1, 2010 Full text Cite

Normal Tissue Sparing with Patient-specific Margins in IMRT Boost Plans for Cervical Cancer

Conference International Journal of Radiation Oncology*Biology*Physics · November 2009 Full text Cite

Investigation of the feasibility of relative 3D dosimetry in the Radiologic Physics Center Head and Neck IMRT phantom using presage/optical-CT.

Journal Article Med Phys · July 2009 Featured Publication This study presents the application of the Presage/optical-CT 3D dosimetry system for relative dosimetry in the Radiologic Physics Center (RPC) Head and Neck (H&N) IMRT phantom. Performance of the system was evaluated by comparison with the "gold-standard" ... Full text Link to item Cite

SU‐FF‐J‐103: Concepts for Normal Tissue Sparing with Patient‐Specific Margins in IMRT Boost Treatments for Cervix

Conference Medical Physics · January 1, 2009 Purpose: This concept study quantifies the potential for normal tissue sparing in IMRT boost plans for cervical cancer by employing patient‐specific margins. Various PTV expansion margins are evaluated, including best‐case and standard‐case scenarios, whic ... Full text Cite

TU‐E‐304A‐06: A 3D Solution for Advanced Photon Arc Therapy Quality Assurance

Conference Medical Physics · January 1, 2009 Purpose: Recently, radiation treatment technology has out‐paced the advances in QA technology, and a critical gap has been created within the arc motion delivery systems such as Rapid Arc®, High Art®, and VMAT®. Gantry position, speed and MU rate create ex ... Full text Cite

TH‐D‐BRB‐03: The Application of a Novel Three Dimensional Dosimetry System to the Acquisition of Commissioning Data of Small Photon Fields

Conference Medical Physics · January 1, 2009 Purpose: To investigate the application of a radiochromic plastic 3D dosimeter to the measurement of commissioning data in radiosurgery fields. Method and Materials: In order to measure total scatter factors, a single cylinder of a radiochromic plastic (PR ... Full text Cite

SU‐FF‐I‐153: First Experience of High Resolution 3D Optical‐CT Scanning of An Anthropomorphic, Leuco‐Dye Doped, Radiochromic Plastic Dosimeter

Conference Medical Physics · January 1, 2009 Purpose: To investigate feasibility of high‐resolution three dimensional (3D) optical‐CT scanning of an anthropomorphic leuco‐dye doped radiochromic plastic dosimeter. Method and Materials: An anthropomorphic head phantom made out of PRESAGE™ (a leuco‐dye‐ ... Full text Cite

SU‐FF‐T‐482: Extension of An Informatics Architecture to Compare and Analyze 3D Dosimetric Data

Conference Medical Physics · January 1, 2009 Purpose: Novel 3D dosimetry techniques illustrate the urgent clinical need for tools for the comparison and visualization of dose data from various dosimeters. We present results from a collaborative effort to develop clinically useful methods to view, com ... Full text Cite

A comprehensive evaluation of the PRESAGE/optical-CT 3D dosimetry system.

Journal Article Med Phys · January 2009 Featured Publication This work presents extensive investigations to evaluate the robustness (intradosimeter consistency and temporal stability of response), reproducibility, precision, and accuracy of a relatively new 3D dosimetry system comprising a leuco-dye doped plastic 3D ... Full text Link to item Cite

Investigating the Feasibility of 3D Dosimetry in the RPC IMRT H&N Phantom.

Journal Article J Phys Conf Ser · 2009 Featured Publication An urgent requirement for 3D dosimetry has been recognized because of high failure rate (~25%) in RPC credentialing, which relies on point and 2D dose measurements. Comprehensive 3D dosimetry is likely to resolve more errors and improve IMRT quality assura ... Full text Link to item Cite

An Investigation into the Robustness of Optical-CT Dosimetry of a Radiochromic Dosimeter Compatible with the RPC Head-and-Neck Phantom.

Journal Article J Phys Conf Ser · January 1, 2009 Featured Publication The potential of the PRESAGE™/Optical-CT system as a comprehensive 3D dosimetry tool has been demonstrated. The current study focused on detailed characterization of robustness (intra-dosimeter uniformity and temporal stability) and reproducibility (inter- ... Full text Link to item Cite

Improving the quantitative accuracy of optical-emission computed tomography by incorporating an attenuation correction: application to HIF1 imaging.

Journal Article Phys Med Biol · October 7, 2008 Featured Publication Optical computed tomography (optical-CT) and optical-emission computed tomography (optical-ECT) are new techniques for imaging the 3D structure and function (including gene expression) of whole unsectioned tissue samples. This work presents a method of imp ... Full text Link to item Cite

An investigation of the accuracy of an IMRT dose distribution using two- and three-dimensional dosimetry techniques.

Journal Article Med Phys · May 2008 Featured Publication Complex dose delivery techniques like intensity-modulated radiation therapy (IMRT) require dose measurement in three dimensions for comprehensive validation. Previously, we demonstrated the feasibility of the "PRESAGE/optical-computed tomography (CT)" syst ... Full text Link to item Cite

TU‐FF‐A4‐03: Improving the Accuracy of Optical‐Emission‐CT Imaging Through Application of a Non‐Uniform Attenuation Correction

Conference Medical Physics · January 1, 2008 Purpose: Optical computed tomography (optical‐CT) and emission tomography (optical‐ECT) are new techniques with demonstrated potential for imaging structure and function (including gene expression) in unsectioned tissue samples. This work presents the firs ... Full text Cite

SU‐GG‐T‐438: Rind Radiosurgery: Investigation of a Novel Radiation Therapy Technique for the Treatment of Intracranial Lesions

Conference Medical Physics · January 1, 2008 Purpose: Rind radiosurgery is a highly modulated technique that aims to treat the proliferative disease of ring‐enhancing intracranial lesions, and to reduce the dose to normal brain tissue when compared with conventional radiosurgery. This study aims to q ... Full text Cite

TU‐D‐AUD C‐02: An Investigation of the Consistency and Robustness of the PRESAGE/optical‐CT 3D Dosimetry System

Conference Medical Physics · January 1, 2008 Purpose: The potential of the PRESAGE™/Optical‐CT system as a comprehensive 3D dosimetry tool has been demonstrated. Detailed characterization of intra‐dosimeter uniformity, temporal stability, inter‐dosimeter reproducibility and robustness have yet to be ... Full text Cite

SU‐GG‐J‐28: An Investigation of Intra and Inter‐Fraction Motion in Cervical Cancer Patients

Conference Medical Physics · January 1, 2008 Purpose: To quantify the intra‐fraction motion of the cervix at various time points during a course of external beam radiation therapy. Also to develop patient‐specific PTV margins that can account for the observed intra‐fraction motion for cervix patients ... Full text Cite

TU‐FF‐A2‐06: The Verification of Respiratory‐Gated Radiation Treatments Using 3D Dosimetry Techniques

Conference Medical Physics · January 1, 2008 Purpose: This work investigates the feasibility of verifying respiratory gated treatments using a new 3D dosimetry system consisting of a radiochromic plastic (PRESAGE™) with optical‐CT readout. Method and Materials: Three identical PRESAGE™ dosimeters (5c ... Full text Cite

SU‐GG‐T‐153: Scaling the Prescription Dose: How Accurate Is the Varian Delivery System?

Conference Medical Physics · January 1, 2008 Purpose: The prescribed dose of an IMRT treatment plan may need to be scaled without changing any other parameters of the plan (e.g. relative fluence‐maps). Examples include changing the prescription as ordered by the physician, or rescaling the dose to av ... Full text Cite

SU‐GG‐T‐135: Evaluation of PRESAGE/optical‐CT 3D Dosimetry for Commissioning a Linac for IMRT

Conference Medical Physics · January 1, 2008 Purpose: PRESAGE is a novel radiochromic plastic which, in combination with optical‐CT imaging, has been shown to have outstanding potential for high‐resolution three‐dimensional (3D) dosimetry. Here, the first application of PRESAGE/optical‐CT to commissi ... Full text Cite

Fast, high-resolution 3D dosimetry utilizing a novel optical-CT scanner incorporating tertiary telecentric collimation.

Journal Article Med Phys · January 2008 Featured Publication This study introduces a charge coupled device (CCD) area detector based optical-computed tomography (optical-CT) scanner for comprehensive verification of radiation dose distributions recorded in nonscattering radiochromic dosimeters. Defining characterist ... Full text Link to item Cite

Optical clearing of unsectioned specimens for three-dimensional imaging via optical transmission and emission tomography.

Journal Article J Biomed Opt · 2008 Featured Publication Optical computed tomography (optical-CT) and optical emission computed tomography (optical-ECT) are new techniques that enable unprecedented high-resolution 3-D multimodal imaging of tissue structure and function. Applications include imaging macroscopic g ... Full text Link to item Cite

An implantable MOSFET dosimeter for the measurement of radiation dose in tissue during cancer therapy

Journal Article IEEE Sensors Journal · January 1, 2008 This paper describes the functionality, radiation characteristics, and clinical implementation of an implantable MOSFET radiation detector (dosimeter). The dosimeter is powered by radio frequency telemetry eliminating the need for a power source inside the ... Full text 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

Functional imaging in bulk tissue specimens using optical emission tomography: fluorescence preservation during optical clearing.

Journal Article Phys Med Biol · April 21, 2007 Featured Publication Optical emission computed tomography (optical-ECT) is a technique for imaging the three-dimensional (3D) distribution of fluorescent probes in biological tissue specimens with high contrast and spatial resolution. In optical-ECT, functional information can ... Full text Link to item Cite

Radiation sensitive films and gels

Chapter · January 1, 2007 Radiographic film is the dosimeter of choice for a wide range of therapeutic and diagnostic applications in radiation-therapy departments. It is particularly useful for qualitative measurements of ionising radiation beams (e.g. high and low energy x-rays a ... Full text Cite

Three-dimensional imaging of whole rodent organs using optical computed and emission tomography.

Journal Article J Biomed Opt · 2007 Featured Publication We explore the potential of optical computed tomography (optical-CT) and optical emission computed tomography (optical-ECT) in a new area-whole organ imaging. The techniques are implemented on an in-house prototype benchtop system with improved image quali ... Full text Link to item Cite

SU‐FF‐T‐98: Characterization of Buildup Effects in OneDosePlus MOSFET‐Based Dosimeters

Conference Medical Physics · January 1, 2007 Purpose: Evaluate the buildup cap used on OneDosePlus™ MOSFET dosimeters and study the field size, angular, and SSD dependency. Method and Materials: OneDosePlus (ODP) dosimeters are single use, pre‐calibrated MOSFETs used to measure entrance patient dose. ... Full text Cite

WE‐E‐AUD‐03: Characterization of a Novel, Fast, In‐House, CCD‐Based Optical‐CT Scanner for 3D Dosimetry in Radiochromic Dosimeters

Conference Medical Physics · January 1, 2007 Purpose: Practical tools for comprehensive three‐dimensional (3D) dosimetry are urgently needed. Here we evaluate a novel, in‐house, second‐generation optical‐computed tomography (optical‐CT) scanner for 3D‐dosimetry in PRESAGE™ dosimeters. Primary advanta ... Full text Cite

SU‐FF‐T‐208: Evaluation of a New Radiochromic Film/Flatbed Scanner System for Planar Clinical Dosimetry

Conference Medical Physics · January 1, 2007 Purpose: To assess the accuracy and practicality of using GAFCHROMIC® EBT Film in combination with an Epson flat‐bed scanner for the verification of advanced treatment techniques in radiation therapy. The combination of EBT with flat‐bed scanner may repres ... Full text Cite

WE‐E‐AUD‐04: Radiation Characteristics and Hypo‐Fractionation Dose Response for the DVS Implantable MOSFET Dosimeter

Conference Medical Physics · January 1, 2007 Purpose: Evaluation of the radiation characteristics and performance of the DVS® implantable MOSFET dosimeter for typical and hypo‐fractionated protocols. Method and Materials: The commercially available DVS is calibrated for use in the range of 150–250 cG ... Full text Cite

Quality assurance in 3D dosimetry by optical-CT.

Journal Article J Phys Conf Ser · December 1, 2006 Featured Publication Full text Link to item Cite

A dual-purpose CCD based micro-optical-CT scanning system.

Journal Article J Phys Conf Ser · December 1, 2006 Featured Publication Full text Link to item Cite

PRESAGETM - Development and optimization studies of a 3D radiochromic plastic dosimeter-Part 2

Journal Article Journal of Physics: Conference Series · December 1, 2006 In a previous paper we described the evaluation of seven different transparent plastics as dosimeter matrices along with six different leuco dyes as the radiochromic agent. Here we present the evaluation of the dosimeter sensitivity and post irradiation st ... Full text Cite

Investigation of the dosimetric characteristics of PRESAGETM

Journal Article Journal of Physics: Conference Series · December 1, 2006 In this work we perform a detailed investigation of the fundamental dosimetric characteristics of PRESAGETM, to determine its potential for dosimetry. A common problem encountered when attempting to evaluate a new material, is how to efficiently evaluate t ... Full text Cite

Simple 3D validation experiments for PRESAGETM/optical-CT dosimetry

Journal Article Journal of Physics: Conference Series · December 1, 2006 Detailed studies of the basic dosimetric properties of small volumes of PRESAGETM have confirmed its promise as a new material with enhanced properties for 3D dosimetry. PRESAGETM is a transparent polyurethane material containing a radiochromic leucodye. P ... Full text Cite

2726

Conference International Journal of Radiation Oncology*Biology*Physics · November 2006 Full text Cite

2875

Conference International Journal of Radiation Oncology*Biology*Physics · November 2006 Full text Cite

2885

Conference International Journal of Radiation Oncology*Biology*Physics · November 2006 Full text Cite

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Conference International Journal of Radiation Oncology*Biology*Physics · November 2006 Full text Cite

A practical three-dimensional dosimetry system for radiation therapy.

Journal Article Med Phys · October 2006 Featured Publication There is a pressing need for a practical three-dimensional (3D) dosimetry system, convenient for clinical use, and with the accuracy and resolution to enable comprehensive verification of the complex dose distributions typical of modern radiation therapy. ... Full text Link to item Cite

Three-dimensional imaging of xenograft tumors using optical computed and emission tomography.

Journal Article Med Phys · September 2006 Featured Publication The physical basis and preliminary applications of optical computed tomography (optical-CT) and optical emission computed tomography (optical-ECT) are introduced, as new techniques with potential to provide unique 3D information on a variety of aspects of ... Full text Link to item Cite

Characterization of a new radiochromic three-dimensional dosimeter.

Journal Article Med Phys · May 2006 Featured Publication The development of intensity-modulated radiotherapy (IMRT) has created a clear need for a dosimeter that can accurately and conveniently measure dose distributions in three dimensions to assure treatment quality. PRESAGE is a new three dimensional (3D) dos ... 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

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

TH‐C‐ValB‐04: Evaluation of the Quality of 3D‐3D Mutual Information (MI) Shared Between Reference and On‐Board DTS Images

Conference Medical Physics · January 1, 2006 Purpose: Digital tomosynthesis (DTS) is a fast, low‐dose method for reconstructing 3‐D slices from 2‐D cone‐beam x‐ray projection data acquired with limited source angulation (e.g., 40°). We previously developed a method for reconstructing reference DTS (R ... Full text Cite

3D dosimetry by optical-CT scanning.

Journal Article J Phys Conf Ser · 2006 Featured Publication The need for an accurate, practical, low-cost 3D dosimetry system is becoming ever more critical as modern dose delivery techniques increase in complexity and sophistication. A recent report from the Radiological Physics Center (RPC) (1), revealed that 38% ... Full text Link to item Cite

IMRT verification using a radiochromic/optical-CT dosimetry system.

Journal Article J Phys Conf Ser · 2006 Featured Publication 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

SU‐FF‐T‐230: Evaluation of the Performance of An Optical CT Scanner

Conference Medical Physics · January 1, 2006 Purpose: Optical CT technology has received much attention recently in the areas of 3D gel dosimetry and biological imaging, owing to its uniqueness in offering high contrast 3D images for optically transparent objects. In this work we evaluate the perform ... Full text Cite

WE‐D‐330A‐02: Optical‐Computed‐and Emmission Tomography: Applications in Cancer Research

Conference Medical Physics · January 1, 2006 Purpose: This work explores the potential of optical‐computed and emission‐tomography (OCT/OET), when coupled with optical clearing techniques, for imaging aspects of biological structure and function for cancer research. OCT/OET are the optical analogues ... Full text Cite

SU‐FF‐T‐89: An Exploration of New Formulations for PRESAGETM 3D Dosimetry

Conference Medical Physics · January 1, 2006 Purpose: Presage is a new radiochromic material with substantial promise as a practical and convenient 3D dosimeter. Here we investigate new formulations of PRESAGETM to determine formulations that have high sensitivity, high stability, and/or are amenable ... Full text Cite

SU‐FF‐T‐219: Evaluation of a Practical and Low Cost Gafchromic Film/flat‐Bed Scanner Combination for Planar Dosimetry

Conference Medical Physics · January 1, 2006 Purpose: To assess the accuracy and practicality of using GAFCHROMIC® EBT Film in combination with an Epson flat‐bed scanner for the verification of advanced treatment techniques in radiation therapy. EBT is a new type of Gafchromic film with high sensitiv ... Full text Cite

WE‐D‐330A‐01: 3D Optical Imaging of Tumor Microvasculature and Viable Cell Distribution

Conference Medical Physics · January 1, 2006 Purpose: The ability to image 3D global structure (e.g. microvasculature) and function (e.g. gene expression) in whole unsectioned tumors, in high‐resolution and with high‐contrast, is of significant present interest in cancer research. We have developed n ... Full text Cite

TU‐C‐224C‐02: A Practical and Accurate 3D Dosimetry System for Radiation Therapy

Conference Medical Physics · January 1, 2006 Purpose: At present, clinical dosimeters are limited to point or planar measurement, and hence do not provide the comprehensive 3D information ideal for verification of advanced delivery techniques. In this work we present a clinically viable 3D dosimetry ... Full text Cite

Assessment of Setup Accuracy for Prostate Radiotherapy using On-board Imaging and Cone Beam Computed Tomography

Conference International Journal of Radiation Oncology*Biology*Physics · October 2005 Full text Cite

Online Digital Tomosynthesis (DTS): A Novel Technique for Improving Target Localization in Radiation Therapy

Conference International Journal of Radiation Oncology*Biology*Physics · October 2005 Full text Cite

Intrafraction Organ Motion of the Normal Cervix

Conference International Journal of Radiation Oncology*Biology*Physics · October 2005 Full text Cite

A Novel Method of Imaging Unperturbed Tumor Vasculature in 3D

Conference International Journal of Radiation Oncology*Biology*Physics · October 2005 Full text Cite

PRESAGE - A Promising New Material for 3D Dosimetry

Conference International Journal of Radiation Oncology*Biology*Physics · October 2005 Full text Cite

Combining Cardiac/Respiratory Gating to Minimize the Organ Motion Effect

Conference International Journal of Radiation Oncology*Biology*Physics · October 2005 Full text Cite

Initial application of digital tomosynthesis with on-board imaging in radiation oncology

Journal Article Progress in Biomedical Optics and Imaging - Proceedings of SPIE · August 25, 2005 We present preliminary investigations that examine the feasibility of incorporating digital tomosynthesis into radiation oncology practice with the use of kilovoltage on-board imagers (OBI). Modern radiation oncology linear accelerators now include hardwar ... Full text Cite

Cone-beam-CT guided radiation therapy: technical implementation.

Journal Article Radiother Oncol · June 2005 Featured Publication BACKGROUND AND PURPOSE: X-ray volumetric imaging system (XVI) mounted on a linear accelerator is available for image guidance applications. In preparation for clinical implementation, phantom and patient imaging studies were conducted to determine the irra ... Full text Link to item Cite

Cone-beam-CT guided radiation therapy: A model for on-line application.

Journal Article Radiother Oncol · June 2005 Featured Publication BACKGROUND AND PURPOSE: This paper presents efficient and generalized processes for the clinical application of on-line X-ray volumetric cone-beam CT imaging (XVI) to improve the accuracy of patient set-up in radiation therapy. XVI image-guided therapy is ... Full text Link to item Cite

Optical-CT imaging of complex 3D dose distributions.

Journal Article J Phys Conf Ser · April 2005 Featured Publication The limitations of conventional dosimeters restrict the comprehensiveness of verification that can be performed for advanced radiation treatments presenting an immediate and substantial problem for clinics attempting to implement these techniques. In essen ... Full text Link to item Cite

Predicting radiotherapy-induced cardiac perfusion defects.

Journal Article Med Phys · January 2005 Featured Publication The purpose of this work is to compare the efficacy of mathematical models in predicting the occurrence of radiotherapy-induced left ventricular perfusion defects assessed using single-photon emission computed tomography (SPECT). The basis of this study is ... Full text Link to item Cite

WE‐D‐T‐617‐01: Characterization of a New 3D Dosimetric Material “PRESAGE” TM

Conference Medical Physics · January 1, 2005 Purpose: A pressing goal of modern radiation dosimetry is the development of effective and convenient three‐dimensional (3D) dosimetry systems that can measure and verify complex dose distributions. 3D dosimetry materials do exist but improvements would be ... Full text Cite

SU‐FF‐T‐257: The Study of the Dosimetric Properties of ‘RadGel’, a New Dosimeter for Three‐Dimensional Gel Dosimetry

Conference Medical Physics · January 1, 2005 Purpose: The development of advanced radiation treatment techniques such as IMRT has prompted an immediate need for a dosimetry system that can provide accurate and convenient measurement of complex three‐dimensional (3D) dose distributions. Gel dosimetry ... Full text Cite

SU‐FF‐J‐30: Quantification of Normal Organ Motion Due to the Respiratory and Cardiac Cycles

Conference Medical Physics · January 1, 2005 Purpose: To quantify the degree of normal organ motion due to the respiratory and cardiac cycles. Better definition of such motion may be useful in defining field margins and in assessing the utility of gating technologies. Method and Materials: Four healt ... Full text Cite

WE‐E‐T‐6E‐01: Multidimensional Dosimetry Without Film Processors

Conference Medical Physics · January 1, 2005 Introduction: Radiographic film has been a mainstay for quality assurance procedures within radiation oncology departments. Prior to 3D conformal therapy, treatments were planned using kilovoltage portal films (simulator films). After the introduction of 3 ... Full text Cite

WE‐E‐J‐6C‐01: TOMAS, a Tool for Organ Motion AnalysiS

Conference Medical Physics · January 1, 2005 Purpose: On line cone‐beam x‐ray CT is a promising technique for image‐guided‐radiation‐therapy (IGRT) by virtue of its ability to provide soft tissue contrast in 3D. IGRT enables correction for inter‐fraction set‐up error and organ motion, which can impro ... Full text Cite

SU‐FF‐J‐57: Digital Tomosynthesis for Verification of Radiation Therapy Positioning: Preliminary Results From a Kilovoltage On‐Board Imaging System

Conference Medical Physics · January 1, 2005 Purpose: This study introduces a new radiation therapy target localization technique using online digital tomosynthesis (DTS), a method for reconstructing 3‐D slices from 2‐D projection data acquired with limited source motion. By separating the visualizat ... Full text Cite

WE‐D‐I‐609‐05: Optical Imaging of Tumor Microvasculature in 3D

Conference Medical Physics · January 1, 2005 Purpose: Great interest exists at present in determining methods to image and understand tumor micro‐vasculature structure and how it can be perturbed by a variety of agents, including radiation and anti‐angiogenic drug therapies. Present methods including ... Full text Cite

Optical-CT gel-dosimetry. II: Optical artifacts and geometrical distortion.

Journal Article Med Phys · May 2004 Featured Publication There is a clear need for technology that enables accurate, high-resolution, three-dimensional (3D) measurement of intricate dose distributions associated with modern radiation treatments. A potential candidate has emerged in the form of water-equivalent " ... Full text Link to item Cite

Evaluation of a 2D diode array for IMRT quality assurance.

Journal Article Radiother Oncol · February 2004 Featured Publication BACKGROUND AND PURPOSE: The QA of intensity modulated radiotherapy (IMRT) dosimetry is a laborious task. The goal of this work is to evaluate the dosimetric characteristics of a new 2D diode array (MapCheck from Sun Nuclear Corporation, Melbourne, Florida) ... Full text Link to item Cite

Optical-CT scanning of polymer gels.

Journal Article J Phys Conf Ser · 2004 Featured Publication The application of optical-CT scanning to achieve accurate high-resolution 3D dosimetry is a subject of current interest. The purpose of this paper is to provide a brief overview of past research and achievements in optical-CT polymer gel dosimetry, and to ... Full text Link to item Cite

Optical-CT gel-dosimetry I: basic investigations.

Journal Article Med Phys · April 2003 Featured Publication Comprehensive verification of the intricate dose distributions associated with advanced radiation treatments is now an immediate and substantial problem. The task is challenging using traditional dosimeters because of restrictions to point measurements (io ... Full text Link to item Cite

Practical aspects of in situ 16O (gamma,n) 15O activation using a conventional medical accelerator for the purpose of perfusion imaging.

Journal Article Med Phys · August 2001 Featured Publication We report investigations into the feasibility of generating radioactive oxygen (15O, a positron emitter, with half-life 2.05 min) using a tuned Elekta SL25 accelerator, for the end purpose of imaging tumor perfusion. 15O is produced by the "gamma, neutron, ... Full text Link to item Cite

High resolution gel-dosimetry by optical-CT and MR scanning.

Journal Article Med Phys · July 2001 Featured Publication The increased intricacy of Intensity-Modulated-Radiation-Therapy (IMRT) delivery has created the need for a high-resolution 3D-dosimetry (three-dimensional) system capable of measuring and verifying the complex delivery. Present clinical methods are inadeq ... Full text Link to item Cite

Radiation physics and applications in therapeutic medicine

Journal Article Physics Education · January 1, 2001 Radiation therapy is an example of the successful application of advanced physics to the treatment of human disease leading to improved quality of life and even cure for many patients. The German physicist William Roentgen (1845–1923), who discovered x-ray ... Full text Cite

An investigation comparing optical CT with MR scanning for polymer gel dosimetry

Journal Article Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings · December 1, 2000 An overview is given of an optical scanning system and a preliminary study that compares, for the same gel samples, MR with optical scanning. The comparison has two parts: calibration methods and accuracy; and noise and resolution in dosimetric images. A n ... Cite

Rind-therapy: A new approach to treatment and management of larger brain lesions

Journal Article Annual International Conference of the IEEE Engineering in Medicine and Biology - Proceedings · December 1, 2000 A new technique for the treatment and management of larger brain lesions is presented. The technique, so called rind-therapy, achieves boosting the dose to rapidly proliferating tumour tissue at the periphery of the lesion. This technique boosts the periph ... Cite

Radiation dosimetry using polymer gels: methods and applications.

Journal Article Br J Radiol · September 2000 Featured Publication New, complex radiotherapy delivery techniques require dosimeters that are able to measure complex three-dimensional dose distributions accurately and with good spatial resolution. Polymer gel is an emerging new dosimeter being applied to these challenges. ... Full text Link to item Cite

Noise in polymer gel measurements using MRI.

Journal Article Med Phys · August 2000 Featured Publication With the development of conformal radiotherapy, particularly intensity modulated radiation therapy (IMRT), there is a clear need for multidimensional dosimeters. A commercial polymerizing gel, BANG-2 gel (MGS Research, Inc., Guilford, CT), has recently bee ... Full text Link to item Cite

Optimized MR imaging for polyacrylamide gel dosimetry.

Journal Article Phys Med Biol · April 2000 Featured Publication Polyacrylamide gels are a powerful tool to measure radiation dose by quantifying the NMR T2 relaxation times of the irradiated gel. The exploitation of these radiation sensitive gels in clinical radiotherapy requires accurate mapping of T2 values. This pap ... Full text Link to item Cite

Dose mapping of inhomogeneities positioned in radiosensitive polymer gels

Journal Article Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment · December 1, 1999 A gel matrix (gelatin), infused with acrylamide monomer and a crosslinking agent has been used as a three-dimensional dosimeter of X- and γ-rays as used in radiotherapy. Magnetic resonance imaging is used to create a parameter map of transverse relaxation ... Full text Cite

Experimental 3D dosimetry around a high-dose-rate clinical 192Ir source using a polyacrylamide gel (PAG) dosimeter.

Journal Article Phys Med Biol · October 1999 Featured Publication It is well known that the experimental dosimetry of brachytherapy sources presents a challenge. Depending on the particular-dosimeter used, measurements can suffer from poor spatial resolution (ion chambers), lack of 3D information (film) or errors due to ... Full text Link to item Cite

Comparison of intensity-modulated tomotherapy with stereotactically guided conformal radiotherapy for brain tumors.

Journal Article Int J Radiat Oncol Biol Phys · September 1, 1999 Featured Publication PURPOSE: Intensity-modulated radiotherapy (IMRT) offers the potential to more closely conform dose distributions to the target, and spare organs at risk (OAR). Its clinical value is still being defined. The present study aims to compare IMRT with stereotac ... Full text Link to item Cite

Beam-orientation customization using an artificial neural network.

Journal Article Phys Med Biol · September 1999 Featured Publication A methodology for the constrained customization of coplanar beam orientations in radiotherapy treatment planning using an artificial neural network (ANN) has been developed. The geometry of the patients, with cancer of the prostate, was modelled by reducin ... Full text Link to item Cite

Dynamics of polymerization in polyacrylamide gel (PAG) dosimeters: (I) ageing and long-term stability.

Journal Article Phys Med Biol · August 1999 Featured Publication Few quantitative data are available on the kinetics of polymerization reactions in polymer gel (PAG) dosimeters and their long-term stability. Post-irradiation polymerization reactions have been found to continue for several weeks, posing questions regardi ... Full text Link to item Cite

A comparison of coplanar four-field techniques for conformal radiotherapy of the prostate.

Journal Article Radiother Oncol · June 1999 Featured Publication BACKGROUND AND PURPOSE: Conformal radiotherapy of the prostate is an increasingly common technique, but the optimal choice of beam configuration remains unclear. This study systematically compares a number of coplanar treatment plans for four-field irradia ... Full text Link to item Cite

Is it possible to optimize a radiotherapy treatment plan?

Journal Article Int J Radiat Oncol Biol Phys · February 1, 1999 Featured Publication Full text Link to item Cite

Constrained customization of non-coplanar beam orientations in radiotherapy of brain tumours.

Journal Article Phys Med Biol · February 1999 Featured Publication A methodology for the constrained customization of non-coplanar beam orientations in radiotherapy treatment planning has been developed and tested on a cohort of five patients with tumours of the brain. The methodology employed a combination of single and ... Full text Link to item Cite

A comparison of conventional and conformal radiotherapy of the oesophagus: work in progress.

Journal Article Br J Radiol · October 1998 Featured Publication A retrospective treatment planning study was carried out in five patients to assess the effectiveness of conformal radiotherapy of the oesophagus. A two-phase conventional treatment plan was created for each patient, with a prescribed dose of 55 Gy. This p ... Full text Link to item Cite

Improving calibration accuracy in gel dosimetry.

Journal Article Phys Med Biol · October 1998 Featured Publication A new method of calibrating gel dosimeters (applicable to both Fricke and polyacrylamide gels) is presented which has intrinsically higher accuracy than current methods, and requires less gel. Two test-tubes of gel (inner diameter 2.5 cm, length 20 cm) are ... Full text Link to item Cite

A case study comparing the relative benefit of optimizing beam weights, wedge angles, beam orientations and tomotherapy in stereotactic radiotherapy of the brain.

Journal Article Phys Med Biol · August 1998 Featured Publication A treatment-planning case study has been performed on a patient with a medium-sized, convex brain tumour. The study involved the application of advanced treatment-plan optimization techniques to improve on the dose distribution of the 'standard plan' used ... Full text Link to item Cite

Improvements in prostate radiotherapy from the customization of beam directions.

Journal Article Med Phys · July 1998 Featured Publication A methodology for optimizing the beam directions in radiotherapy treatment planning has been developed and tested on a cohort of twelve prostate patients. An optimization algorithm employing a an objective cost function was used, based on beam's-eye-view v ... Full text Link to item Cite

An investigation into the dosimetry of a nine-field tomotherapy irradiation using BANG-gel dosimetry.

Journal Article Phys Med Biol · May 1998 Featured Publication BANG-gel dosimetry offers the potential for measuring the dose delivered by a radiotherapy treatment technique, in three dimensions, with high spatial resolution and good accuracy. The ability to measure comprehensively a 3D dose distribution is a major ad ... Full text Link to item Cite

Methods for transferring patient and plan data between radiotherapy treatment planning systems.

Journal Article Br J Radiol · July 1997 Featured Publication The effectiveness of conformal radiotherapy can ultimately only be assessed by the use of clinical trials. As large multicentre clinical trials become more widespread, methods of transferring patient and plan data between radiotherapy treatment planning sy ... Full text Link to item Cite

Intensity-modulated radiotherapy by means of static tomotherapy: a planning and verification study.

Journal Article Med Phys · June 1997 Featured Publication There is currently much research interest in developing, evaluating, and verifying intensity-modulation techniques. Of particular interest is how well the delivery of intensity-modulated profiles can be simulated by planning algorithms, and how accurately ... Full text Link to item Cite

Advanced methods for delivering conformal therapy and dose planning techniques

Journal Article Physica Medica · January 1, 1997 Highly-conformal dose-distributions can be created by the superposition of many radiation fields from different directions, each with its intensity spatially modulated. One class of treatment technique, sometimes referred to as tomotherapy, involves creati ... Cite

Methods for transferring patient and plan data between radiotherapy treatment planning systems

Journal Article British Journal of Radiology · 1997 The effectiveness of conformai radiotherapy can ultimately only be assessed by the use of clinical trials. As large multicentre clinical trials become more widespread, methods of transferring patient and plan data between radiotherapy treatment planning sy ... Cite

A method to study the characteristics of 3D dose distributions created by superposition of many intensity-modulated beams delivered via a slit aperture with multiple absorbing vanes.

Journal Article Phys Med Biol · October 1996 Featured Publication Highly conformal dose distributions can be created by the superposition of many radiation fields from different directions, each with its intensity spatially modulated by the method known as tomotherapy. At the planning stage, the intensity of radiation of ... Full text Link to item Cite

The optimisation of wedge filters in radiotherapy of the prostate.

Journal Article Radiother Oncol · December 1995 Featured Publication A treatment plan optimisation algorithm has been applied to 12 patients with early prostate cancer in order to determine the optimum beam-weights and wedge angles for a standard conformal three-field treatment technique. The optimisation algorithm was base ... Full text Link to item Cite

Comparison of treatment techniques for conformal radiotherapy of the prostate using dose-volume histograms and normal tissue complication probabilities.

Journal Article Radiother Oncol · October 1995 Featured Publication The aim of this study was to evaluate the relative merits of the coplanar field arrangements most frequently used for conformal radiotherapy of the prostate using dose-volume histograms and normal tissue complication probabilities (NTCPs). Twelve patients ... Full text Link to item Cite

The optimization and inherent limitations of 3D conformal radiotherapy treatment plans of the prostate.

Journal Article Br J Radiol · August 1995 Featured Publication This paper describes the applications of an inverse planning optimization algorithm to the real clinical problem of prostate cancer. The algorithm has been designed to compute optimized beam-weights taking full account of three-dimensional spatial informat ... Full text Link to item Cite

A comparison of conventional 'forward planning' with inverse planning for 3D conformal radiotherapy of the prostate.

Journal Article Radiother Oncol · June 1995 Featured Publication A radiotherapy treatment plan optimisation algorithm has been applied to 48 prostate plans and the results compared with those of an experienced human planner. Twelve patients were used in the study, and 3-, 4-, 6- and 8-field plans (with standard coplanar ... Full text Link to item Cite