Scholars@Duke
Nimmi Ramanujam

Nimmi Ramanujam

Robert W. Carr, Jr., Distinguished Professor of Biomedical Engineering
Biomedical Engineering
Box 90281, 1427 FCIEMAS, Durham, NC 27708-0281
367 Gross Hall, 140 Science Drive, Durham, NC 27708

Selected Publications

Usability of Speculum-Compatible Injection Devices for Administering Ethyl Cellulose-Ethanol Ablation to Treat Cervical Neoplasia in Low- and Middle-Income Countries.

Journal Article Annals of biomedical engineering · October 2025 PurposeCurrent treatments for cervical neoplasia are often inaccessible in low- and middle-income countries (LMICs), which contributes to high cervical cancer mortality. We previously developed a low-cost ablative therapy using ethanol mixed with ... Full text Cite

Automated Image Clarity Detection for the Improvement of Colposcopy Imaging with Multiple Devices.

Journal Article Biomed Signal Process Control · February 2025 UNLABELLED: The proportion of women dying from cervical cancer in middle- and low-income countries is over 60%, twice that of their high-income counterparts. A primary screening strategy to eliminate this burden is cervix visualization and application of 3 ... Full text Link to item Cite

Development of Image Pre-processing Toolbox to Boost Cervical Cancer Detection

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · January 1, 2025 Globally, inequitable resources and access cause cervical cancer remain the fourth leading cause of death in women. Risk stratification with human papilloma virus (HPV) screening is fundamental in identifying vulnerable populations. Visual inspection with ... Full text Cite

Multi-probe Metabolic Fluorescence Microscopy Captures Poor Tumor Immunogenicity

Conference Optical Molecular Probes Imaging and Drug Delivery Omp 2025 in Proceedings Optica Biophotonics Congress 2025 Part of Optica Biophotonics Congress Optics in the Life Sciences · January 1, 2025 Visualizing complex tumor-immune metabolic interactions is imperative to understanding cancer progression. Cocultures of 4T1 tumor cells and CD8+ T cells were imaged for glucose uptake and mitochondrial metabolism. Results point to poor immunogenic tumor p ... Full text Cite

Biomedical Engineering for Global Health Cancer, Inequity, and Technology

Book · July 31, 2024 Explore the fundamentals of biomedical engineering technologies with this thought-provoking introduction, framed around modern-day global cancer inequities. ... Cite

Evaluating Tumor Hypoxia Radiosensitization Via Electron Paramagnetic Resonance Oxygen Imaging (EPROI).

Journal Article Mol Imaging Biol · June 2024 PURPOSE: Tumor hypoxia contributes to aggressive phenotypes and diminished therapeutic responses to radiation therapy (RT) with hypoxic tissue being 3-fold less radiosensitive than normoxic tissue. A major challenge in implementing hypoxic radiosensitizers ... Full text Link to item Cite

Impact of Injection-Based Delivery Parameters on Local Distribution Volume of Ethyl-Cellulose Ethanol Gel in Tissue and Tissue Mimicking Phantoms.

Journal Article IEEE transactions on bio-medical engineering · May 2024 ObjectiveLocal drug delivery aims to minimize systemic toxicity by preventing off-target effects; however, injection parameters influencing depot formation of injectable gels have yet to be thoroughly studied. We explored the effects of needle cha ... Full text Cite

A color-based tumor segmentation method for clinical ex vivo breast tissue assessment utilizing a multi-contrast brightfield imaging strategy.

Journal Article J Biophotonics · May 2024 We demonstrate an automated two-step tumor segmentation method leveraging color information from brightfield images of fresh core needle biopsies of breast tissue. Three different color spaces (HSV, CIELAB, YCbCr) were explored for the segmentation task. B ... Full text Link to item Cite

A Multiplexed Quantitative Spectroscopy Method to Measure Spectrally Overlapping Metabolic Fluorophores

Conference Novel Optical Materials and Applications Noma 2024 in Proceedings Advanced Photonics Congress 2024 Part of Optica Advanced Photonics Congress · January 1, 2024 We have developed and validated an in vivo quantitative spectroscopy method to measure spectrally overlapping fluorophores relevant to cancer metabolism using an inverse Monte Carlo algorithm and linear spectral unmixing. ... Cite

Metabolic Imaging as a Tool to Characterize Chemoresistance and Guide Therapy in Triple-Negative Breast Cancer (TNBC).

Journal Article Molecular cancer research : MCR · October 2023 After an initial response to chemotherapy, tumor relapse is frequent. This event is reflective of both the spatiotemporal heterogeneities of the tumor microenvironment as well as the evolutionary propensity of cancer cell populations to adapt to variable c ... Full text Cite

In Vivo Evaluation of Safety and Efficacy of Ethyl Cellulose-Ethanol Tissue Ablation in a Swine Cervix Model.

Journal Article Bioengineering (Basel, Switzerland) · October 2023 Current therapies for treating cervical dysplasia are often inaccessible in low and middle-income countries (LMICs), highlighting the need for novel low-cost therapies that can be delivered at the point of care. Ethanol ablation is a low-cost therapy desig ... Full text Cite

Feasibility and Outcome of Training Field Workers to Use the Transvaginal Colposcope for Point of Care Diagnosis and Management of Precancerous Cervical Lesions

Journal Article Indian Journal of Gynecologic Oncology · March 1, 2023 Background: Screening programs in low-middle-income countries have high attrition rates during referral and treatment. Portable colposcopes can decrease costs, reduce referral rates and improve compliance with treatment especially if performed at primary c ... Full text Cite

Community-Centered Design Thinking as a Scalable Stem Learning Intervention

Journal Article Advances in Engineering Education · January 1, 2023 Background: Through the human-centered design process (HCD), students, referred to as learners, can use a personal lens to contextualize engineering concepts and solve real-world problems (Goldman and Kabayadondo 2016). The Ignite program, created by the C ... Full text Open Access Cite

Adaptive Design of Fluorescence Imaging Systems for Custom Resolution, Fields of View, and Geometries.

Journal Article BME frontiers · January 2023 Objective and Impact Statement: We developed a generalized computational approach to design uniform, high-intensity excitation light for low-cost, quantitative fluorescence imaging of in vitro, ex vivo, and in vivo samples with a single device. I ... Full text Cite

In Vivo Metabolic Imaging Reveals Mitochondrial Membrane Potential Reprogramming During Residual Disease Following Chemotherapy

Conference Optical Molecular Probes Imaging and Drug Delivery Omp 2023 · January 1, 2023 We performed intravital fluorescent microscopy in preclinical models of disease regression in Triple Negative Breast Cancer to compare dynamic, long-term in vivo changes across three major metabolic axes in chemotherapy-resistant and chemotherapy-sensitive ... Cite

Development of a multi-scale platform to quantify metabolic heterogeneity in vivo

Conference Optical Molecular Probes Imaging and Drug Delivery Omp 2023 · January 1, 2023 We developed an approach to quantify intratumoral metabolic heterogeneity of in vivo tumor models by leveraging a computationally designed multi-scale microscope and a suite of exogenous fluorescent contrast agents to provide functional and structural info ... Cite

Can portable Colposcopes Replace Standard-of-care Colposcopes? A Crossover Trial of Two Portable Colposcopes with a Standard-of-Care Video Colposcope.

Journal Article Asian Pacific journal of cancer prevention : APJCP · December 2022 BackgroundScreen positive women need to be triaged by colposcopy which is a major challenge in low-middle income countries. Portable colposcopes may overcome many challenges, reduce referrals and enable a single visit approach. This study assessed ... Full text Cite

Development of a multimodal mobile colposcope for real-time cervical cancer detection.

Journal Article Biomedical optics express · October 2022 Cervical cancer remains a leading cause of cancer death among women in low-and middle-income countries. Globally, cervical cancer prevention programs are hampered by a lack of resources, infrastructure, and personnel. We describe a multimodal mobile colpos ... Full text Cite

In vivo metabolic imaging identifies lipid vulnerability in a preclinical model of Her2+/Neu breast cancer residual disease and recurrence.

Journal Article NPJ Breast Cancer · September 26, 2022 Recurrent cancer cells that evade therapy is a leading cause of death in breast cancer patients. This risk is high for women showing an overexpression of human epidermal growth factor receptor 2 (Her2). Cells that persist can rely on different substrates f ... Full text Link to item Cite

Ethanol Ablation Therapy Drives Immune-Mediated Antitumor Effects in Murine Breast Cancer Models.

Journal Article Cancers (Basel) · September 25, 2022 Ethanol ablation is a minimally invasive, cost-effective method of destroying tumor tissue through an intratumoral injection of high concentrations of cytotoxic alcohol. Ethyl-cellulose ethanol (ECE) ablation, a modified version of ethanol ablation, contai ... Full text Link to item Cite

A Spectroscopic Technique to Simultaneously Characterize Fatty Acid Uptake, Mitochondrial Activity, Vascularity, and Oxygen Saturation for Longitudinal Studies In Vivo.

Journal Article Metabolites · April 19, 2022 Aggressive breast cancer has been shown to shift its metabolism towards increased lipid catabolism as the primary carbon source for oxidative phosphorylation. In this study, we present a technique to longitudinally monitor lipid metabolism and oxidative ph ... Full text Link to item Cite

KeyLoop: Mechanical Retraction of the Abdominal Wall for Gasless Laparoscopy.

Journal Article Surg Innov · February 2022 Background. Despite favorable outcomes of laparoscopic surgery in high-income countries, its implementation in low- and middle-income countries (LMICs) is challenging given a shortage of consumable supplies, high cost, and risk of power outages. To overcom ... Full text Link to item Cite

[18F]Fluoro-DCP, a first generation PET radiotracer for monitoring protein sulfenylation in vivo.

Journal Article Redox biology · February 2022 Redox metabolism plays essential functions in the pathology of cancer and many other diseases. While several radiotracers for imaging redox metabolism have been developed, there are no reports of radiotracers for in vivo imaging of protein oxidation. Here ... Full text Cite

Evaluation of Women's Empowerment in a Community-Based Human Papillomavirus Self-Sampling Social Entrepreneurship Program (Hope Project) in Peru: A Mixed-Method Study.

Journal Article Frontiers in public health · January 2022 IntroductionUnderstanding community women's relational and financial empowerment in social entrepreneurship could be the key to scaling up community-based human papillomavirus (HPV) self-sampling programs in low- and middle-income countries. The H ... Full text Cite

Cervical Cancer-Related Knowledge, Attitudes, Practices and Self-Screening Acceptance Among Patients, Employees, and Social Media Followers of Major Brazilian Hospital.

Journal Article Cancer control : journal of the Moffitt Cancer Center · January 2022 BackgroundBrazil has a high burden of cervical cancer, even though it is preventable, traceable and treatable. Hence, this study evaluated levels of knowledge, attitudes and practices (KAP) related to cervical cancer screening and diagnosis and ac ... Full text Cite

Multicontrast Pocket Colposcopy Cervical Cancer Diagnostic Algorithm for Referral Populations.

Journal Article BME frontiers · January 2022 Objective and Impact Statement. We use deep learning models to classify cervix images-collected with a low-cost, portable Pocket colposcope-with biopsy-confirmed high-grade precancer and cancer. We boost classification performance on a screened-posi ... Full text Cite

Minimally invasive ethyl cellulose ethanol ablation in domesticated cats with naturally occurring head and neck cancers: Six cats.

Journal Article Veterinary and comparative oncology · September 2021 It is difficult to retain tumoricidal doses of ethanol in large or unencapsulated tumours without causing intoxication or damaging surrounding tissue. Ethyl cellulose-ethanol ablation (ECEA) overcomes this limitation by trapping ethanol intratumorally. To ... Full text Cite

Optimizing ethyl cellulose-ethanol delivery towards enabling ablation of cervical dysplasia.

Journal Article Sci Rep · August 19, 2021 In low-income countries, up to 80% of women diagnosed with cervical dysplasia do not return for follow-up care, primarily due to treatment being inaccessible. Here, we describe development of a low-cost, portable treatment suitable for such settings. It is ... Full text Link to item Cite

An Accessible Laparoscope for Surgery in Low- and Middle- Income Countries.

Journal Article Ann Biomed Eng · July 2021 Laparoscopic surgery is the standard of care in high-income countries for many procedures in the chest and abdomen. It avoids large incisions by using a tiny camera and fine instruments manipulated through keyhole incisions, but it is generally unavailable ... Full text Link to item Cite

Resetting the tumor microenvironment to favor anti-tumor immunity after local ablation.

Conference Journal of Clinical Oncology · May 20, 2021 2561 Background: Percutaneous tumor ablation is a non-surgical method of tumor destruction that leaves necrotic tumor debris in situ. Tumor associated antigens released after ablation have the potential to initiate a systemic ant ... Full text Cite

Digital Health Strategies for Cervical Cancer Control in Low- and Middle-Income Countries: Systematic Review of Current Implementations and Gaps in Research.

Journal Article Journal of medical Internet research · May 2021 BackgroundNearly 90% of deaths due to cervical cancer occur in low- and middle-income countries (LMICs). In recent years, many digital health strategies have been implemented in LMICs to ameliorate patient-, provider-, and health system-level chal ... Full text Cite

Policy Considerations to Promote Equitable Cervical Cancer Screening and Treatment in Peru.

Journal Article Annals of global health · January 2021 BackgroundCervical cancer is one of the leading causes of death among Peruvian women. Women seeking screening or treatment services experience delays in receiving screening results provided at community clinics or district hospitals, and lack suff ... Full text Cite

Digital Health Strategies for Cervical Cancer Control in Low- and Middle-Income Countries: Systematic Review of Current Implementations and Gaps in Research (Preprint)

Journal Article · August 17, 2020 BACKGROUNDNearly 90% of deaths due to cervical cancer occur in low- and middle-income countries (LMICs). In recent years, many digital health strategies have been implemented in LMICs to ... Full text Cite

Understanding Factors Governing Distribution Volume of Ethyl Cellulose-Ethanol to Optimize Ablative Therapy in the Liver.

Journal Article IEEE transactions on bio-medical engineering · August 2020 ObjectiveEthanol ablation, the injection of ethanol to induce necrosis, was originally used to treat hepatocellular carcinoma, with survival rates comparable to surgery. However, efficacy is limited due to leakage into surrounding tissue. To reduc ... Full text Cite

Combining multiple contrasts for improving machine learning-based classification of cervical cancers with a low-cost point-of-care Pocket colposcope.

Conference Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference · July 2020 We apply feature-extraction and machine learning methods to multiple sources of contrast (acetic acid, Lugol's iodine and green light) from the white Pocket Colposcope, a low-cost point of care colposcope for cervical cancer screening. We combine features ... Full text Cite

Optical Technologies for Improving Healthcare in Low-Resource Settings: introduction to the feature issue.

Journal Article Biomedical optics express · June 2020 This feature issue of Biomedical Optics Express presents a cross-section of interesting and emerging work of relevance to optical technologies in low-resource settings. In particular, the technologies described here aim to address challenges to meet ... Full text Cite

Leveraging surface Hsp90 expression for rapid-on-site breast cancer diagnostics

Conference Optics Infobase Conference Papers · January 1, 2020 We developed a portable, low-cost, handheld fluorescent microscope to perform rapid heat shock protein 90 (Hsp90) molecular imaging. The source of non-specific signal and diffusion kinetics of the probe is studied. ... Cite

In vivo metabolic imaging reveals mitochondrial membrane potential reprogramming following Her2-targeted therapy and dormant disease

Conference Optics Infobase Conference Papers · January 1, 2020 We performed in intravital fluorescent microscopy in a preclinical cancer dormancy model to capture key changes in mitochondrial activity associated with Her2 treated breast cancer both acutely and in a residual disease state. ... Cite

Development of Algorithms for Automated Detection of Cervical Pre-Cancers With a Low-Cost, Point-of-Care, Pocket Colposcope.

Journal Article IEEE Trans Biomed Eng · August 2019 GOAL: In this paper, we propose methods for (1) automatic feature extraction and classification for acetic acid and Lugol's iodine cervigrams and (2) methods for combining features/diagnosis of different contrasts in cervigrams for improved performance. ME ... Full text Link to item Cite

Optical Imaging of Glucose Uptake and Mitochondrial Membrane Potential to Characterize Her2 Breast Tumor Metabolic Phenotypes.

Journal Article Molecular cancer research : MCR · July 2019 With the large number of women diagnosed and treated for breast cancer each year, the importance of studying recurrence has become evident due to most deaths from breast cancer resulting from tumor recurrence following therapy. To mitigate this, cellular a ... Full text Cite

Simultaneous in vivo optical quantification of key metabolic and vascular endpoints reveals tumor metabolic diversity in murine breast tumor models.

Journal Article J Biophotonics · April 2019 Therapeutically exploiting vascular and metabolic endpoints becomes critical to translational cancer studies because altered vascularity and deregulated metabolism are two important cancer hallmarks. The metabolic and vascular phenotypes of three sibling b ... Full text Link to item Cite

Exploiting heat shock protein expression to develop a non-invasive diagnostic tool for breast cancer.

Journal Article Sci Rep · March 5, 2019 Leveraging the unique surface expression of heat shock protein 90 (Hsp90) in breast cancer provides an exciting opportunity to develop rapid diagnostic tests at the point-of-care setting. Hsp90 has previously been shown to have elevated expression levels a ... Full text Link to item Cite

Portable Pocket colposcopy performs comparably to standard-of-care clinical colposcopy using acetic acid and Lugol's iodine as contrast mediators: an investigational study in Peru.

Journal Article BJOG · September 2018 OBJECTIVE: Our goal was to develop a tele-colposcopy platform for primary-care clinics to improve screening sensitivity and access. Specifically, we developed a low-cost, portable Pocket colposcope and evaluated its performance in a tertiary healthcare cen ... Full text Open Access Link to item Cite

Near-simultaneous quantification of glucose uptake, mitochondrial membrane potential, and vascular parameters in murine flank tumors using quantitative diffuse reflectance and fluorescence spectroscopy.

Journal Article Biomed Opt Express · July 1, 2018 The shifting metabolic landscape of aggressive tumors, with fluctuating oxygenation conditions and temporal changes in glycolysis and mitochondrial metabolism, is a critical phenomenon to study in order to understand negative treatment outcomes. Recently, ... Full text Link to item Cite

Assessing effects of pressure on tumor and normal tissue physiology using an automated self-calibrated, pressure-sensing probe for diffuse reflectance spectroscopy.

Journal Article J Biomed Opt · May 2018 Diffuse reflectance spectroscopy (DRS) represents a quantitative, noninvasive, nondestructive means of assessing vascular oxygenation, vascularity, and structural properties. However, it is known that such measurements can be influenced by the effects of p ... Full text Link to item Cite

Metaboloptics: Visualization of the tumor functional landscape via metabolic and vascular imaging.

Journal Article Sci Rep · March 8, 2018 Many cancers adeptly modulate metabolism to thrive in fluctuating oxygen conditions; however, current tools fail to image metabolic and vascular endpoints at spatial resolutions needed to visualize these adaptations in vivo. We demonstrate a high-resolutio ... Full text Link to item Cite

An integrated strategy for improving contrast, durability, and portability of a Pocket Colposcope for cervical cancer screening and diagnosis.

Journal Article PLoS One · 2018 INTRODUCTION: We have previously developed a portable Pocket Colposcope for cervical cancer screening in resource-limited settings. In this manuscript we report two different strategies (cross-polarization and an integrated reflector) to improve image cont ... Full text Link to item Cite

Image processing and machine learning techniques to automate diagnosis of Lugol's iodine cervigrams for a low-cost point-of-care digital colposcope

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · January 1, 2018 The world health organization recommends visual inspection with acetic acid (VIA) and/or Lugol's Iodine (VILI) for cervical cancer screening in low-resource settings. Human interpretation of diagnostic indicators for visual inspection is qualitative, subje ... Full text Cite

Optimizing fluorescently-tethered Hsp90 inhibitor dose for maximal specific uptake by breast tumors

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · January 1, 2018 Despite improvements in surgical resection, 20-40% of patients undergoing breast conserving surgery require at least one additional re-excision. Leveraging the unique surface expression of heat shock protein 90 (Hsp90), a chaperone protein involved in seve ... Full text Cite

Non-invasive, simultaneous quantification of vascular oxygenation, glucose uptake and mitochondria membrane potential in a flank tumor model

Conference Optics Infobase Conference Papers · January 1, 2018 For the first time, we performed simultaneous in vivo spectroscopy of tissue hemoglobin, 2-NBDG, and TMRE in a preclinical model, to successfully capture vascular and metabolic parameters in vivo in solid tumors. ... Full text Cite

Preventing over treatment through smart health technologies

Conference Optics Infobase Conference Papers · January 1, 2018 The cost of cancer care in the U.S. was $125 billion in 2010 and is projected to increase to $175 billion by 2020. Total spending on cancer care is driven by the cost to treat an individual patient and the number of patients treated. For example, sipuleuce ... Full text Cite

Clinical evaluation of a portable pocket colposcope for cervical cancer screening in the United States, Perú, and Tanzania

Conference 2017 IEEE Healthcare Innovations and Point of Care Technologies Hi Poct 2017 · December 19, 2017 Cervical cancer is the second leading cause of cancer related deaths for women worldwide, despite being both preventable and treatable if detected early enough. The burden of disease persists in part due to a lack of access to early diagnostics and the fac ... Full text Cite

Distinct Angiogenic Changes during Carcinogenesis Defined by Novel Label-Free Dark-Field Imaging in a Hamster Cheek Pouch Model.

Journal Article Cancer Res · December 15, 2017 There remain gaps in knowledge concerning how vascular morphology evolves during carcinogenesis. In this study, we imaged neovascularization by label-free dark-field microscopy of a 7,12-Dimethylbenz[a]anthracene (DMBA)-induced hamster cheek pouch model of ... Full text Link to item Cite

Leveraging ectopic Hsp90 expression to assay the presence of tumor cells and aggressive tumor phenotypes in breast specimens.

Journal Article Sci Rep · December 13, 2017 Hsp90 has been studied extensively as a therapeutic target in breast cancer in pre-clinical and clinical trials, demonstrating a variety of roles in metastatic progression. The evidence to date suggests a compelling opportunity to leverage attributes of Hs ... Full text Link to item Cite

Near-simultaneous intravital microscopy of glucose uptake and mitochondrial membrane potential, key endpoints that reflect major metabolic axes in cancer.

Journal Article Sci Rep · October 23, 2017 While the demand for metabolic imaging has increased in recent years, simultaneous in vivo measurement of multiple metabolic endpoints remains challenging. Here we report on a novel technique that provides in vivo high-resolution simultaneous imaging of gl ... Full text Link to item Cite

Development of enhanced ethanol ablation as an alternative to surgery in treatment of superficial solid tumors.

Journal Article Sci Rep · August 18, 2017 While surgery is at the foundation of cancer treatment, its access is limited in low-income countries. Here, we describe development of a low-cost alternative therapy based on intratumoral ethanol injection suitable for resource-limited settings. Although ... Full text Link to item Cite

Design and preliminary analysis of a vaginal inserter for speculum-free cervical cancer screening

Dataset · May 5, 2017 Abstract: Cervical cancer screening usually requires use of a speculum to provide a clear view of the cervix. The speculum is one potential barrier to screening due to fear of pain, discomfort and embarrassment. The aim of this paper is to present and demo ... Full text Cite

International Image Concordance Study to Compare a Point-of-Care Tampon Colposcope With a Standard-of-Care Colposcope.

Journal Article J Low Genit Tract Dis · April 2017 OBJECTIVE: Barriers to cervical cancer screening in low-resource settings include lack of accessible, high-quality services, high cost, and the need for multiple visits. To address these challenges, we developed a low-cost, intravaginal, optical cervical i ... Full text Open Access Link to item Cite

Miniature spectral imaging device for wide-field quantitative functional imaging of the morphological landscape of breast tumor margins.

Journal Article J Biomed Opt · February 1, 2017 We have developed a portable, breast margin assessment probe leveraging diffuse optical spectroscopy to quantify the morphological landscape of breast tumor margins during breast conserving surgery. The approach presented here leverages a custom-made 16-ch ... Full text Link to item Cite

Design and preliminary analysis of a vaginal inserter for speculum-free cervical cancer screening.

Journal Article PLoS One · 2017 OBJECTIVE: Cervical cancer screening usually requires use of a speculum to provide a clear view of the cervix. The speculum is one potential barrier to screening due to fear of pain, discomfort and embarrassment. The aim of this paper is to present and dem ... Full text Link to item Cite

Imaging of 2-NBDG and TMRE reveals glucose uptake and mitochondrial membrane potential in dorsal window chamber models

Conference Optics Infobase Conference Papers · January 1, 2017 For the first time, we performed simultaneous in vivo microscopic imaging of 2-NBDG and TMRE in a preclinical model, to successfully capture glucose and mitochondrial membrane potential on the same tissue site at one time. ... Full text Cite

Oxygen and Perfusion Kinetics in Response to Fractionated Radiation Therapy in FaDu Head and Neck Cancer Xenografts Are Related to Treatment Outcome.

Journal Article Int J Radiat Oncol Biol Phys · October 1, 2016 PURPOSE: To test whether oxygenation kinetics correlate with the likelihood for local tumor control after fractionated radiation therapy. METHODS AND MATERIALS: We used diffuse reflectance spectroscopy to noninvasively measure tumor vascular oxygenation an ... Full text Link to item Cite

Algorithms for differentiating between images of heterogeneous tissue across fluorescence microscopes.

Journal Article Biomed Opt Express · September 1, 2016 Fluorescence microscopy can be used to acquire real-time images of tissue morphology and with appropriate algorithms can rapidly quantify features associated with disease. The objective of this study was to assess the ability of various segmentation algori ... Full text Link to item Cite

Dark field optical imaging reveals vascular changes in an inducible hamster cheek pouch model during carcinogenesis.

Journal Article Biomedical optics express · September 2016 In this study, we propose a low-cost cross-polarized dark field microscopy system for in vivo vascular imaging to detect head and neck cancer. A simple-to-use Gabor-filter-based image processing technique was developed to objectively and automatical ... Full text Cite

Rapid staining and imaging of subnuclear features to differentiate between malignant and benign breast tissues at a point-of-care setting.

Journal Article J Cancer Res Clin Oncol · July 2016 PURPOSE: Histopathology is the clinical standard for tissue diagnosis; however, it requires tissue processing, laboratory personnel and infrastructure, and a highly trained pathologist to diagnose the tissue. Optical microscopy can provide real-time diagno ... Full text Link to item Cite

Correlation of breast tissue histology and optical signatures to improve margin assessment techniques.

Journal Article J Biomed Opt · June 1, 2016 Optical spectroscopy is sensitive to morphological composition and has potential applications in intraoperative margin assessment. Here, we evaluate ex vivo breast tissue and corresponding quantified hematoxylin & eosin images to correlate optical scatteri ... Full text Link to item Cite

WE-FG-201-01: Patient Centric Technologies for Diagnosis of Breast and Cervical Cancer.

Journal Article Medical physics · June 2016 Many low- and middle-income countries lack the resources and services to manage cancer, from screening and diagnosis to radiation therapy planning, treatment and quality assurance. The challenges in upgrading or introducing the needed services are enormous ... Full text Cite

Label-free vascular imaging in a spontaneous hamster cheek pouch carcinogen model for pre-cancer detection (Conference Presentation)

Conference Optical Biopsy XIV: Toward Real-Time Spectroscopic Imaging and Diagnosis · April 26, 2016 Full text Cite

Handbook of biomedical optics

Book · April 19, 2016 Biomedical optics holds tremendous promise to deliver effective, safe, non- or minimally invasive diagnostics and targeted, customizable therapeutics. Handbook of Biomedical Optics provides an in-depth treatment of the field, including coverage of applicat ... Cite

Portable system for wide-field, sub-millimeter functional imaging of the morphological landscape of breast tumor margins

Conference Optics Infobase Conference Papers · April 18, 2016 We have developed a portable, breast margin assessment probe (BMAP) that surgeons can use to evaluate the breast tumor margin status during surgery. The approach presented here leverages a custom16-channel photodiode array raster-scanning-based system with ... Full text Cite

Structured Illumination Microscopy and a Quantitative Image Analysis for the Detection of Positive Margins in a Pre-Clinical Genetically Engineered Mouse Model of Sarcoma.

Dataset · 2016 Intraoperative assessment of surgical margins is critical to ensuring residual tumor does not remain in a patient. Previously, we developed a fluorescence structured illumination microscope (SIM) system with a single-shot field of view (FOV) of 2.1 × 1.6 m ... Full text Open Access Link to item Cite

A Fluorescence-Guided Laser Ablation System for Removal of Residual Cancer in a Mouse Model of Soft Tissue Sarcoma.

Journal Article Theranostics · 2016 The treatment of soft tissue sarcoma (STS) generally involves tumor excision with a wide margin. Although advances in fluorescence imaging make real-time detection of cancer possible, removal is limited by the precision of the human eye and hand. Here, we ... Full text Open Access Link to item Cite

Hyperspectral imaging of glucose uptake, mitochondrial membrane potential, and vascular oxygenation differentiates breast cancers with distinct metastatic potential in vivo

Conference Optics Infobase Conference Papers · January 1, 2016 We performed in vivo hyperspectral imaging in a preclinical cancer model to capture key metabolic endpoints (glucose uptake, mitochondrial membrane potential, and vascular oxygenation) to successfully distinguish metastatic and non-metastatic tumors. ... Full text Cite

Integrated dual-modal microscope for imaging of key metabolic and vascular endpoints in preclinical cancer models

Conference Optics Infobase Conference Papers · January 1, 2016 We have developed and utilized a wide field, high resolution microscope to capture multiple key metabolic and vascular endpoints to different indolent from metastatic disease. ... Full text Cite

A quantitative microscopic approach to predict local recurrence based on in vivo intraoperative imaging of sarcoma tumor margins.

Journal Article Int J Cancer · November 15, 2015 The goal of resection of soft tissue sarcomas located in the extremity is to preserve limb function while completely excising the tumor with a margin of normal tissue. With surgery alone, one-third of patients with soft tissue sarcoma of the extremity will ... Full text Link to item Cite

Micro-anatomical quantitative optical imaging: toward automated assessment of breast tissues.

Journal Article Breast cancer research : BCR · August 2015 IntroductionPathologists currently diagnose breast lesions through histologic assessment, which requires fixation and tissue preparation. The diagnostic criteria used to classify breast lesions are qualitative and subjective, and inter-observer di ... Full text Cite

Light for Life: International Year of Light 2015.

Journal Article Journal of biomedical optics · June 2015 Full text Cite

Data from: Design of a novel low cost point of care tampon (POCkeT) colposcope for use in resource limited settings

Dataset · May 15, 2015 Current guidelines by WHO for cervical cancer screening in low- and middle-income countries involves visual inspection with acetic acid (VIA) of the cervix, followed by treatment during the same visit or a subsequent visit with cryotherapy if a suspicious ... Cite

Data for manuscript "A Quantitative Diffuse Reflectance Imaging (QDRI) System for Comprehensive Surveillance of the Morphological Landscape in Breast Tumor Margins"

Dataset · March 3, 2015 This repository contains the clinical patient data, along with representative images and mat files, of the data for the manuscript submitted to PLOS ONE entitled "A Quantitative Diffuse Reflectance Imaging (QDRI) System for Comprehensive Surveillance of th ... Open Access Cite

Chromophore based analyses of steady-state diffuse reflectance spectroscopy: current status and perspectives for clinical adoption.

Journal Article Journal of biophotonics · January 2015 Diffuse reflectance spectroscopy is a rapidly growing technology in the biophotonics community where it has shown promise in its ability to classify different tissues. In the steady-state domain a wide spectrum of clinical applications is supported with th ... Full text Cite

Non-invasive, simultaneous quantification of vascular oxygenation and glucose uptake in tissue.

Journal Article PloS one · January 2015 We report the development of non-invasive, fiber-based diffuse optical spectroscopy for simultaneously quantifying vascular oxygenation (SO2) and glucose uptake in solid tumors in vivo. Glucose uptake was measured using a fluorescent glucose analog, 2-[N-( ... Full text Cite

A Quantitative Diffuse Reflectance Imaging (QDRI) System for Comprehensive Surveillance of the Morphological Landscape in Breast Tumor Margins.

Journal Article PLoS One · 2015 In an ongoing effort to address the clear clinical unmet needs surrounding breast conserving surgery (BCS), our group has developed a next-generation multiplexed optical-fiber-based tool to assess breast tumor margin status during initial surgeries. Specif ... Full text Link to item Cite

Design of a Novel Low Cost Point of Care Tampon (POCkeT) Colposcope for Use in Resource Limited Settings.

Journal Article PLoS One · 2015 INTRODUCTION: Current guidelines by WHO for cervical cancer screening in low- and middle-income countries involves visual inspection with acetic acid (VIA) of the cervix, followed by treatment during the same visit or a subsequent visit with cryotherapy if ... Full text Open Access Link to item Cite

Assessment of the sensitivity and specificity of tissue-specific-based and anatomical-based optical biomarkers for rapid detection of human head and neck squamous cell carcinoma.

Journal Article Oral Oncol · September 2014 OBJECTIVES: We propose the use of morphological optical biomarkers for rapid detection of human head and neck squamous cell carcinoma (HNSCC) by leveraging the underlying tissue characteristics in aerodigestive tracts. MATERIALS AND METHODS: Diffuse reflec ... Full text Link to item Cite

Measuring tumor cycling hypoxia and angiogenesis using a side-firing fiber optic probe.

Journal Article J Biophotonics · July 2014 Hypoxia and angiogenesis can significantly influence the efficacy of cancer therapy and the behavior of surviving tumor cells. There is a growing demand for technologies to measure tumor hypoxia and angiogenesis temporally in vivo to enable advances in dru ... Full text Link to item Cite

Optical monitoring of glucose demand and vascular delivery in a preclinical murine model

Conference Progress in Biomedical Optics and Imaging Proceedings of SPIE · January 1, 2014 Targeted therapies such as PI3K inhibition can affect tumor vasculature, and hence delivery of imaging agents like FDG, while independently modifying intrinsic glucose demand. Therefore, it is important to identify whether perceived changes in glucose upta ... Full text Cite

Delivery-corrected imaging of fluorescently-labeled glucose reveals distinct metabolic phenotypes in murine breast cancer.

Journal Article PLoS One · 2014 When monitoring response to cancer therapy, it is important to differentiate changes in glucose tracer uptake caused by altered delivery versus a true metabolic shift. Here, we propose an optical imaging method to quantify glucose uptake and correct for in ... Full text Link to item Cite

Preface

Chapter · January 1, 2014 Full text Cite

One-Photon Autofluorescence Microscopy

Chapter · January 1, 2014 Autofluorescence from cells has been detected and utilized by scientists for well over 100 years for a variety of applications. The need for fluorescence as a noninvasive tool for cell studies was spurred by advances in optical microscopy, fueling the need ... Full text Cite

Optimization of illumination frequency and preclinical validation of a wide-field structured illumination microscope designed for imaging in situ tumor margins

Journal Article CLEO Applications and Technology CLEO at 2013 · November 19, 2013 We present a widefield structured illumination microscope for imaging surgical tumor margins in situ. The impact of frequency and turbidity on optical section thickness and SNR was characterized to determine the optimal imaging frequency. © OSA 2013. ... Cite

Abstract C86: Tethered Hsp90 inhibitors carrying optical or radioiodinated probes reveal selective internalization of ectopic Hsp90 in malignant breast tumor cells.

Conference Molecular Cancer Therapeutics · November 1, 2013 AbstractHsp90 inhibitors have demonstrated unusual selectivity for tumor cells despite its ubiquitous expression. This phenomenon has remained unexplained but could be influenced by ectopically expressed Hsp ... Full text Cite

Optical and radioiodinated tethered Hsp90 inhibitors reveal selective internalization of ectopic Hsp90 in malignant breast tumor cells.

Journal Article Chem Biol · September 19, 2013 Inhibitors of heat-shock protein 90 (Hsp90) have demonstrated an unusual selectivity for tumor cells despite its ubiquitous expression. This phenomenon has remained unexplained, but could be influenced by ectopically expressed Hsp90 in tumors. In this work ... Full text Link to item Cite

Monitoring of cycling hypoxia and angiogenesis in FaDu head and neck tumors using a side-firing sensor

Journal Article Progress in Biomedical Optics and Imaging Proceedings of SPIE · May 27, 2013 Many studies have found that hypoxia, particularly cycling hypoxia (CH), can lead to enhanced tumor metastasis and resistance to radiation and chemotherapy. It was also reported that tumor total hemoglobin content (THb), which is directly related to tumor ... Full text Cite

Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Approach for tuning algorithm parameters

Journal Article Progress in Biomedical Optics and Imaging Proceedings of SPIE · May 27, 2013 The combination of fluorescent contrast agents with microscopy is a powerful technique to obtain real time images of tissue histology without the need for fixing, sectioning, and staining. The potential of this technology lies in the identification of robu ... Full text Cite

Data set for "Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Application to the detection of residual disease in tumor margins"

Other · March 12, 2013 This is data that is published in the article "Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Application to the detection of residual disease in tumor margins". ... Open Access Cite

Data set for "Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Application to the detection of residual disease in tumor margins"

Dataset · March 12, 2013 This is data that is published in the article "Quantitative segmentation of fluorescence microscopy images of heterogeneous tissue: Application to the detection of residual disease in tumor margins". ... Open Access Cite

Radiation induces aerobic glycolysis through reactive oxygen species.

Journal Article Radiother Oncol · March 2013 BACKGROUND AND PURPOSE: Although radiation induced reoxygenation has been thought to increase radiosensitivity, we have shown that its associated oxidative stress can have radioprotective effects, including stabilization of the transcription factor hypoxia ... Full text Link to item Cite

Rapid determination of oxygen saturation and vascularity for cancer detection.

Journal Article PLoS One · 2013 A rapid heuristic ratiometric analysis for estimating tissue hemoglobin concentration and oxygen saturation from measured tissue diffuse reflectance spectra is presented. The analysis was validated in tissue-mimicking phantoms and applied to clinical measu ... Full text Link to item Cite

Optimization of illumination frequency and preclinical validation of a wide-field structured illumination microscope designed for imaging in situ tumor margins

Journal Article 2013 Conference on Lasers and Electro Optics CLEO 2013 · January 1, 2013 We present a widefield structured illumination microscope for imaging surgical tumor margins in situ. The impact of frequency and turbidity on optical section thickness and SNR was characterized to determine the optimal imaging frequency. © 2013 The Optica ... Full text Cite

Wavelength optimization for quantitative spectral imaging of breast tumor margins.

Journal Article PLoS One · 2013 A wavelength selection method that combines an inverse Monte Carlo model of reflectance and a genetic algorithm for global optimization was developed for the application of spectral imaging of breast tumor margins. The selection of wavelengths impacts syst ... Full text Open Access Link to item Cite

Quantitative Segmentation of Fluorescence Microscopy Images of Heterogeneous Tissue: Application to the Detection of Residual Disease in Tumor Margins.

Journal Article PLoS One · 2013 PURPOSE: To develop a robust tool for quantitative in situ pathology that allows visualization of heterogeneous tissue morphology and segmentation and quantification of image features. MATERIALS AND METHODS: TISSUE EXCISED FROM A GENETICALLY ENGINEERED MOU ... Full text Link to item Cite

Optical spectral surveillance of breast tissue landscapes for detection of residual disease in breast tumor margins.

Journal Article PLoS One · 2013 We demonstrate a strategy to "sense" the micro-morphology of a breast tumor margin over a wide field of view by creating quantitative hyperspectral maps of the tissue optical properties (absorption and scattering), where each voxel can be deconstructed to ... Full text Link to item Cite

Optimization of a widefield structured illumination microscope for non-destructive assessment and quantification of nuclear features in tumor margins of a primary mouse model of sarcoma.

Journal Article PLoS One · 2013 Cancer is associated with specific cellular morphological changes, such as increased nuclear size and crowding from rapidly proliferating cells. In situ tissue imaging using fluorescent stains may be useful for intraoperative detection of residual cancer i ... Full text Open Access Link to item Cite

Delivery rate affects uptake of a fluorescent glucose analog in murine metastatic breast cancer.

Journal Article PLoS One · 2013 We demonstrate an optical strategy using intravital microscopy of dorsal skin flap window chamber models to image glucose uptake and vascular oxygenation in vivo. Glucose uptake was imaged using a fluorescent glucose analog, 2-[N-(7-nitrobenz-2-oxa-1,3-dia ... Full text Link to item Cite

Image-Guided Oncologic Surgery

Conference MEDICAL PHYSICS · 2012 Full text Cite

Introduction

Journal Article Progress in Biomedical Optics and Imaging Proceedings of SPIE · July 25, 2011 Cite

In Vivo estimation of total hemoglobin concentration and hemoglobin saturation in the detection of cervical epithelial pre-cancers

Conference Optics Infobase Conference Papers · January 1, 2007 Total hemoglobin concentration, hemoglobin saturation and scattering coefficient were extracted from cervical diffuse reflectance spectra (400-600 nm) using a Monte Carlo-based model. Total hemoglobin was shown to distinguish pre-cancerous from normal tiss ... Full text Cite

Imaging human stratified squamous epithelia using nonlinear optical microscopy

Journal Article JOURNAL OF INVESTIGATIVE DERMATOLOGY · April 1, 2006 Link to item Cite

Physiologic, metabolic, and structural alterations in breast cancer: Assessment via optical technologies

Journal Article Optics Infobase Conference Papers · January 1, 2006 Optical spectroscopy was used to assess structural and functional changes which occur in breast tissue for the optical diagnosis of cancer in humans in vivo, and characterization of mammary tumor biology in animal models. © 2006 Optical Society of America. ... Cite

Physiologic, metabolic, and structural alterations in breast cancer: Assessment via optical technologies

Journal Article Optics InfoBase Conference Papers · January 1, 2006 Optical spectroscopy was used to assess structural and functional changes which occur in breast tissue for the optical diagnosis of cancer in humans in vivo, and characterization of mammary tumor biology in animal models. © 2006 Optical Society of America. ... Cite

Physiologic, metabolic, and structural alterations in breast cancer: Assessment via optical technologies

Journal Article Optics Infobase Conference Papers · January 1, 2006 Optical spectroscopy was used to assess structural and functional changes which occur in breast tissue for the optical diagnosis of cancer in humans in vivo, and characterization of mammary tumor biology in animal models. © 2006 Optical Society of America. ... Cite

Physiologic, metabolic, and structural alterations in breast cancer: Assessment via optical technologies

Conference Optics Infobase Conference Papers · January 1, 2006 Optical spectroscopy was used to assess structural and functional changes which occur in breast tissue for the optical diagnosis of cancer in humans in vivo, and characterization of mammary tumor biology in animal models. © 2006 Optical Society of America. ... Full text Cite

Use of genetic algorithms to optimize fiber optic probe design for the extraction of tissue optical properties

Conference Optics Infobase Conference Papers · January 1, 2006 An approach for optimizing the probe geometry for extracting optical properties is developed. It was found that optical properties could be extracted with accuracies of better than 0.5 cm-1, while requiring no a priori assumptions. © 2005 Optica ... Full text Cite

Physiologic, Metabolic, and Structural Alterations in Breast Cancer: Assessment via Optical Technologies

Conference Optics Infobase Conference Papers · January 1, 2006 Optical spectroscopy was used to assess structural and functional changes which occur in breast tissue for the optical diagnosis of cancer in humans in vivo, and characterization of mammary tumor biology in animal models. ... Cite

Monte Carlo based inverse model of diffuse reflectance for determination of UV-VIS optical properties and its application to breast cancer diagnosis

Conference Optics Infobase Conference Papers · January 1, 2004 A method for extracting optical properties from diffuse reflectance spectra is applied to human breast tissue. It was found that using the physically-based model for classification of malignancy performed substantially better than an empirical model. ... Cite

Multiphoton imaging of endogenous fluorescence in neoplastic and non-neoplastic epithelial tissues

Conference Optics Infobase Conference Papers · January 1, 2004 Endogenous fluorescence offers promise for diagnosing oral cancers. This is the first study to use multiphoton imaging to characterize the spatial and depth distribution of endogenous fluorescence in neoplastic and non-neoplastic epithelial tissues. ... Cite

Transabdominal Near-infrared Fetal Brain Oximetry

Conference Optics Infobase Conference Papers · January 1, 2004 The feasibility of transabdominal near-infrared spectroscopy for detecting and quantifying fetal hypoxia in utero is demonstrated in a pregnant ewe model. ... Cite

Imaging collagen in a dermal equivalent using multi-photon microscopy

Conference Optics Infobase Conference Papers · January 1, 2004 Nondestructive imaging of tumor models offers a new tool for cancer research. We have imaged a dermal equivalent and measured a signal decrease using collagenase. This result indicates feasibility for measuring collagen degradation during tumorigenesis. ... Cite

The use of a multi-separation probe for optical diagnosis of breast cancer

Conference Optics Infobase Conference Papers · January 1, 2004 We explored the effects of probe-geometry on UV-VIS fluorescence and diffuse reflectance measurements from breast tissues. It shows that integrated fluorescence intensities measured with a multi-separation probe can be used to discriminate malignant from n ... Cite

Sources of optical contrast in biological tissues

Conference Optics Infobase Conference Papers · January 1, 2003 Cite

Relationship between the depth of a target in a turbid medium and the fluorescence measured using a variable aperture method

Conference Optics Infobase Conference Papers · January 1, 2002 This study shows the relationship between the depth of a target in a turbid medium and the fluorescence ratio profile measured using illumination and collection apertures with variable diameters and the same optical path. The forward problem was studied by ... Cite

Fast and non-invasive fluorescence imaging from biological signals, in vivo using a flying spot scanner

Conference Optics Infobase Conference Papers · January 1, 2000 A flying spot scanner has been developed to image fluorescence from intact tissues in near realtime. The instrument is based on a single-channel detection scheme. The scanner has been used to image fluorescence from living animal tissues undergoing various ... Cite

Comparison between homogeneous and Two-layer model for spectroscopic measurement of fetal cerebral blood oxygenation in-utero

Conference Optics Infobase Conference Papers · January 1, 2000 In order to measure the fetal cerebral oxygenation in utero, a numerical two-layer model data is generated using finite difference method in diffusion regime. The detectibility of photons through the fetal head is estimated and optical properties obtained ... Cite

Antepartum, transabdominal near infrared spectroscopy: Feasibility of measuring photon migration through the fetal head in utero

Journal Article Journal of Maternal Fetal and Neonatal Medicine · January 1, 1999 Objective: We report the feasibility of measuring photon migration through the fetal head in utero using antepartum, transabdominal, near infrared (NIR) spectroscopy. Methods: We developed a continuous wave (CW) spectrometer that incorporates a halogen lig ... Full text Cite

Ig-positive lymphocytes in Hodgkin's disease.

Journal Article N Engl J Med · March 15, 1973 Link to item Cite