A5073976392- Advanced Radiotherapy Techniques
- Medical Imaging Techniques and Applications
- Endometrial and Cervical Cancer Treatments
- Radiation Therapy and Dosimetry
- Advanced X-ray and CT Imaging
- Advanced MRI Techniques and Applications
- Radiomics and Machine Learning in Medical Imaging
- Radiation Dose and Imaging
- Lung Cancer Diagnosis and Treatment
- Prostate Cancer Diagnosis and Treatment
- Management of metastatic bone disease
- MRI in cancer diagnosis
- Digital Radiography and Breast Imaging
- Advances in Oncology and Radiotherapy
- Ultrasound and Hyperthermia Applications
- Glioma Diagnosis and Treatment
- Prostate Cancer Treatment and Research
- Photoacoustic and Ultrasonic Imaging
- Breast Cancer Treatment Studies
- Ocular Oncology and Treatments
- Respiratory and Cough-Related Research
- Nuclear Physics and Applications
- Radiopharmaceutical Chemistry and Applications
- Delphi Technique in Research
- Drug-Induced Ocular Toxicity
Virginia Commonwealth University
2017-2025
University Health System
2025
Ochsner Medical Center
2021-2024
Children's Hospital of Richmond at VCU
2021-2023
Asan Medical Center
2011-2022
University of Ulsan
2012-2022
Ulsan College
2022
University of Toronto
1987-2018
Sunnybrook Health Science Centre
2014-2018
Sunnybrook Research Institute
2015-2018
Purpose: Compressed sensing theory has enabled an accurate, low-dose cone-beam computed tomography (CBCT) reconstruction using a minimal number of noisy projections. However, the time remains significant challenge for practical implementation in clinic. In this work, we propose novel gradient projection algorithm, based on Gradient-Projection-Barzilai-Borwein formulation (GP-BB), that handles total variation (TV)-norm regularization-based least squares problem CBCT highly efficient manner,...
The purpose of this study is to establish a comprehensive set dose measurements data obtained from the X-ray Volumetric Imager (XVI, Elekta Oncology Systems) and On-Board (OBI, Varian Medical cone-beam CT (CBCT) systems. To end, two uniform-density cylindrical acrylic phantoms with diameters 18 cm (head phantom) 30 (body were used for all measurements. Both included ion chamber placement holes in center at periphery (2 below surface). For XVI unit, four standard manufacturer-supplied...
Purpose: Understanding motion characteristics of liver such as, interfractional and intrafractional variability, difference in within different locations the organ, their complex relationship with breathing cycles are particularly important for image‐guided SBRT. The purpose this study was to investigate based on fiducial markers tracked x‐ray projections CBCT scans, taken immediately prior treatments. Methods: Twenty SBRT patients were analyzed. Each patient had three (2 × 5‐mm gold)...
Algorithms for direct tumor tracking in rotational cone-beam projections and reconstruction of phase-binned 3D trajectories were developed. The feasibility the algorithm was demonstrated on a digital phantom, physical phantom two patients. Tracking results obtained by comparing reference templates generated from 4DCT to projections. 95th percentile absolute errors (e95) did not exceed 1.7 mm either imager dimension, while e95 patients 3.3 or less. Accurate reconstructed each case, with...
Recently we have developed an algorithm for reconstructing volumetric images and extracting 3D tumor motion information from a single x-ray projection. We demonstrated its feasibility using digital respiratory phantom with regular breathing patterns. In this work, present detailed description comprehensive evaluation of the improved algorithm. The was by incorporating prediction. accuracy efficiency were then evaluated on 1) phantom, 2) physical 3) five lung cancer patients. These cases...
Purpose Four‐dimensional computed tomography (4DCT) has enhanced images of the thorax and upper abdomen during respiration, but intraphase residual motion artifacts will persist in cine‐mode scanning. In this study, source magnitude projection due to target is investigated. Methods A theoretical model geometric uncertainty partial 4DCT was derived based on ideal periodic motion. Predicted were compared measured errors with a rigid lung phantom attached programmable platform. Ideal actual...
X-ray imaging dose from serial Cone-beam CT (CBCT) scans raises a clinical concern in most image guided radiation therapy procedures. The goal of this paper is to develop fast GPU-based algorithm reconstruct high quality CBCT images undersampled and noisy projection data so as lower the dose. reconstructed by minimizing an energy functional consisting fidelity term total variation regularization term. We GPU-friendly version forward-backward splitting solve problem. A multi-grid technique...
Purpose: All forms of past and current high‐dose‐rate brachytherapy utilize immobile applicators during treatment delivery. The only moving part is the source itself. This paradigm misses an important degree freedom that, if explored, can in some instances produce previously unachievable dose conformality; that is, dynamic motion applicator itself Monte Carlo planning simulations were used to illustrate potential benefits for rectal cancer applications particular. concept termed modulated...
Purpose : Respiration‐induced intrafraction target motion is a concern in liver cancer radiotherapy, especially stereotactic body radiotherapy (SBRT), and therefore, verification of its necessary. An effective means to localize the insert metal fiducial markers or near tumor with simultaneous imaging using cone‐beam computed tomography (CBCT). Utilizing markers, authors have demonstrated method generate breath‐induced signal for reconstructing 4D digital tomosynthesis (4DDTS) 4DCBCT images...
Purpose To evaluate the possibility of utilizing high‐dose rate ( HDR ) 169 Yb and 60 Co sources, in addition to 192 Ir, for treatment skin malignancies with conical applicators. Methods Monte Carlo MC simulations were used benchmark dosimetric parameters single (4140), (Co0.A86), Ir mHDR ‐V2) brachytherapy sources a water phantom compared their results against published data. A standard tungsten alloy Leipzig‐style applicator (Stand.Appl) was determination dose distributions at various...
Imaging through scattering media remains a challenge due to the loss of light intensity and phase, leading poorly reconstructed images with high noise low resolution. Here, we demonstrate new approach, best our knowledge, image unprecedented grayscale accuracy by encoding quantum states within illumination patterns. The orthogonality significantly reduces cross-pixel interference, increases accuracy, simplifies reconstruction. We achieve spatial density 180 dots per inch excellent linearity....
Abstract Purpose This study aims to evaluate how different gantry angles, breathing rates (BPM), cine image speeds, and tracking algorithms affect beam on/off latency the subsequent impact on target dose for a 0.35T MR‐Linac with 6 MV FFF beam. The investigation incorporates an image‐based MRI4D modus QA motion phantom (MQA) measurement‐based plastic scintillation detector (PSD). Methods MQA's was customized insertion 1 mm PSD from BluePhysics. Both MQA were simultaneously synchronized Linac...
The goal of this work was to evaluate the efficacy various image-guided adaptive radiation therapy (IGART) techniques deliver and escalate dose prostate in presence geometric uncertainties. Five patients with 15-16 treatment CT studies each were retrospectively analyzed. All planned an 18 MV, six-field conformal technique a 10 mm margin size initial prescription 70 Gy 35 fractions. strategy employed for patient-specific escalation increase 2 Gy-per-fraction increments until rectum normal...
The goal of this work is to quantify the impact image-guided conformal radiation therapy (CRT) on dose distribution by correcting patient setup uncertainty and inter-fraction tumour motion. This was a retrospective analysis that used five randomly selected prostate cancer patients underwent approximately 15 computed tomography (CT) scans during their treatment course. beam arrangement from plan imported into each repeat CT study recalculated for new setups. Various scenarios were then...