Search Submissions 🔎

Results for "rate measurements": 106 found

4DCT Contrast Protocol for Cardiac Radioablation

Authors: Jeremy S. Bredfeldt, Cindy I. Hancox, Arianna Liles, Alex Marques, Usha Tedrow

Affiliation: Department of Cardiology, Brigham and Women's Hospital, Harvard Medical School, Department of Radiation Oncology, Brigham and Women's Hospital, Harvard Medical School

Abstract Preview: Purpose: Ventricular tachycardia (VT) can be treated using cardiac radioablation. 4DCT simulation is commonly used, however, contrast injection timing is challenging. This study aimed to develop a pro...

A 2D Discrete Ionization Chamber Array for Proton Pencil Beam Scanning Flash Dosimetry

Authors: Fu-Xiong Chang, Arpit M. Chhabra, J Isabelle Choi, Chanda Guha, Nancy Y Lee, Chih-Hsun Lin, Haibo Lin, Hang Qi, Mahbubur Rahman, Charles B. Simone, Pingfang Tsai, Shouyi Wei, Irini Yacoub, Yunjie Yang, Ajay Zheng, Jun Zhou

Affiliation: New York Proton Center, Montefiore Medical Center and Albert Einstein College of Medicine, Liverage Biomedical Inc., Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, Memorial Sloan Kettering Cancer Center, Department of Radiation Oncology and Winship Cancer Institute, Emory University, Institute of Physics, Academia Sinica

Abstract Preview: Purpose: FLASH therapy presents an opportunity to alter the radiotherapy paradigm and significantly enhancing normal organ protection while maintaining the effectiveness of tumor control. The temporal...

A 3D Printed Ion Chamber Insert Solution for Absolute Dosimetry with Varying Ionisation Chambers in Radiosurgery.

Authors: Shashanksharad Kale, Gopishankar Natanasabapathi, Daya Nand Kishore Sharma

Affiliation: All India Institute of Medical Sciences (AIIMS), Department of Radiation Oncology, All India Institute of Medical Sciences

Abstract Preview: Purpose:
The study demonstrates a novel 3D printing method to fabricate an ion chamber insert (ICI) for absolute dosimetry purpose in gamma knife radiosurgery (GKRS).
Methods:
Our institute u...

A Deep Learning Approach to the Prediction of Gamma Passing Rates in VMAT Radiotherapy Plans for Adaptive Treatment.

Authors: Jenghwa Chang, Kuan Huang, Lyu Huang, Jason Lima, Jian Liu, Farzin Motamedi

Affiliation: Northwell, Department of Computer Science and Technology, Kean University, Physics and Astronomy, Hofstra University, Hofstra University Medical Physics Program

Abstract Preview: Title: A Deep Learning Approach to the Prediction of Gamma Passing Rates in VMAT Radiotherapy Plans for Adaptive Treatment.
Purpose: This study aims to develop a deep learning algorithm to predict ...

A Deep Learning-Based Approach for Rapid Prediction of IMRT/VMAT Patient-Specific Quality Assurance for Online Adaptive Plans Generated with a 0.35T MR-Linac

Authors: Suman Gautam, Tianjun Ma, William Song

Affiliation: Virginia Commonwealth University

Abstract Preview: Purpose: We propose an artificial intelligence (AI)-based method to rapidly predict the patient-speciïŹc quality assurance (PSQA) results for magnetic resonance (MR)-guided online adaptive radiation th...

A GPU Accelerated Monte Carlo Dose Engine for Small Animal Proton Radiotherapy

Authors: Haonian Gong, Yue Gu, Meiqi Liu, Zihao Liu, Hsiao-Ming Lu, Yuxiang Wang, Yidong Yang, Cheng Zheng

Affiliation: Hefei Ion Medical Center, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Department of Engineering and Applied Physics, University of Science and Technology of China, University of Science and Technology of China

Abstract Preview: Purpose:
Proton radiotherapy in preclinical small animals requires specific dose engine due to its low energy and small irradiation volume. This study is to develop a GPU-based Monte Carlo dose eng...

A Method to Check the Consistency and Reproducibility of VMAT Delivery

Authors: Chloe Doen Kim, Patricia E. Lindsay, Bern Norrlinger, Jan P. Seuntjens

Affiliation: Princess Margaret Cancer Centre & University of Toronto, Queen's University, Princess Margaret Cancer Centre

Abstract Preview: Purpose: To propose a method to check the consistency of VMAT delivery on linear accelerator (LINAC) with a commercial three-dimensional array device. The method is insensitive to the correction facto...

A Method to Estimate Tumor Motion with Respiration Based on CBCT Projections

Authors: Jie Liu

Affiliation: Inova Health System

Abstract Preview: Purpose:
The respiratory signal commonly acquired by using external surrogates or detecting the diaphragm position only represents the phase information and has poor correlation with the tumor moti...

A Monte Carlo Framework for Automated Quality Assurance of Dynamically Collimated Pencil Beam Scanning Clinical Treatment Deliveries

Authors: Laura Bennett, Wesley S. Culberson, Albert Du, Kevin J. Erhart, Ryan T. Flynn, Ryan Gardner, Alonso N. Gutierrez, Patrick M Hill, Daniel E. Hyer, Eric Jensen, Kaustubh A. Patwardhan, Blake R. Smith, Nhan Vu, Karsten K. Wake

Affiliation: University of Wisconsin, Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin - Madison, Miami Cancer Institute, Baptist Health South Florida, Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Ion Beam Applications (IBA), University of Iowa, Iowa Health Care, .decimal

Abstract Preview: Purpose: To develop and experimentally validate a novel Monte Carlo (MC) framework designed to enable calculation-based quality assurance (QA) for collimated intensity modulated proton therapy treatme...

A New Algorithm for Charged Particle Therapy Beam Energy Measurement By Time-of-Flight

Authors: Sung Woon Choi, Dong Wook Kim, Jin Sung Kim, Na Hye Kwon, Paulo Jorge Ribeiro Da Fonte

Affiliation: Department of Radiation Oncology, Yonsei Cancer Center, Heavy Ion Therapy Research Institute, Yonsei University College of Medicine, Coimbra Institute of Engineering, Polytechnic University of Coimbra

Abstract Preview: Purpose: In hadrontherapy, such as proton and carbon ion therapy, it is desirable, for quality assurance reasons, to have an online beam energy measurement independent from the machine parameters. Sin...

A Novel Setup for Flash Radiotherapy Beam Delivery at Isocenter Using Downstream Electron Scattering

Authors: Dale W. Litzenberg, Ikechi S Ozoemelam, Rowan Paplanus, Michael Pillainayagam, Donald A. Roberts

Affiliation: University of Michigan, Oregon Health & Science University

Abstract Preview: Purpose: Clinical linear accelerators use dual foil scattering systems designed to achieve large uniform fields (up to 25×25cmÂČ), which can reduce beam fluence by up to 93% compared to the unmodified ...

A Perturbative Approach to Determine the Charge Collection Efficiency in High Dose-per-Pulse Beams

Authors: Julien Bancheri, Jan P. Seuntjens

Affiliation: Medical Biophysics, University of Toronto, Princess Margaret Cancer Centre & University of Toronto

Abstract Preview: Purpose: To obtain an analytical expression for the charge collection efficiency of parallel-plate ionization chambers in high dose-per-pulse (DPP) beams that takes into account the square pulse time ...

Absolute Measurement of HDR Ir-192 Air-Kerma Strength Using an Exradin A3 Known-Volume Ionization Chamber

Authors: Larry A. DeWerd, Sean Jollota, Karen Rex Pius Vincent

Affiliation: Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin - Madison

Abstract Preview: Purpose: Absolute measurements, often used to establish primary standards, offer lower measurement uncertainty. For 192Ir high-dose-rate (HDR) brachytherapy, the interim primary standard for air-kerma...

Advancing Flash Radiotherapy: Intercomparison of Parameters between Two Institutions to Optimize Clinical Applications.

Authors: Amir Abdollahi, Celine Karle, Michele M. Kim, Constantinos Koumenis, Andrea Mairani, Erato Stylianou Markidou

Affiliation: Heidelberg Ion-Beam Therapy Center - Department of Radiation Oncology, German Cancer Research Centre(DKFZ), University of Pennsylvania, Physics Dep. University of Cyprus

Abstract Preview: Purpose: The aim is to compare FLASH dose-rate RT generated with protons and carbon (HIT) and compare to protons (UPenn) to provide evidence for equipotency of FLASH vs. standard RT to tumor growth co...

An Alpha Irradiation System for Radiobiological Studies with Versatile Dose Rate Control

Authors: Harsh Arya, Yan Chang, Yujie Chi, Varghese Anto Chirayath, Joshua Rajan, Pan Zui

Affiliation: University of Texas at Arlington, Department of Physics, University of Texas at Arlington

Abstract Preview: Purpose: In targeted alpha therapy (TAT), absorbed dose rates can vary significantly spatially and temporally, impacting therapeutic efficacy as well as carcinogenic potential. This study reports the ...

An End-to-End Test for Adaptive Radiotherapy with Varian Hypersight CBCT Imaging System Using Radiochromic Film in a Rando Pelvis Phantom

Authors: Jameson T. Baker, Yijian Cao, Jenghwa Chang, Sean T Grace, Lyu Huang, Jian Liu, Echezona Simon Obi, Anurag Sharma

Affiliation: Northwell, Hofstra University Medical Physics Program

Abstract Preview: Purpose:
To validate the end-to-end dosimetrical accuracy of Varian HyperSight CBCT for adaptive radiotherapy (ART), from simulation to dose delivery, using radiochromic film dosimetry in a Rando p...

An Evaluation of an SRS Quality Assurance System for Complex Patient Plans.

Authors: John Bennet, Indrin J. Chetty, Tai H. Dou

Affiliation: Department of Radiation Oncology,Cedars Sinai Medical Center, Department of Radiation Oncology, Cedars Sinai Medical Center, Department of Radiation Oncology,Cedars-Sinai Medical Center

Abstract Preview: Purpose:
To investigate the effect of complexity of stereotactic radiosurgery (SRS) volumetric modulated arc therapy plans on gamma pass rates (GPR) using a novel high-resolution ion chamber array ...

An International Survey of High Dose Rate Brachytherapy Dosimetry Practices

Authors: Anna Becker, Tomislav Bokulic, Mauro Carrara, Krzysztof Chelminski, Larry A. DeWerd, Alexis Dimitriadis, Benjamin Kellogg, Malcolm R. McEwen, Zakithi L.M Msimang, Mark J. Rivard, Thorsten Sander, Thorsten Schneider, Jamema Swamidas, Egor Titovich, Paula Toroi, Carlos E. de Almeida, Jacco de Pooter, Liset de la Fuente Rosales, Deborah G. van der Merwe

Affiliation: Radiation and Nuclear Safety Authority, University of Zagreb, National Physical Laboratory, IAEA, Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin - Madison, Rio de Janeiro State University, Dosimetry Laboratory, Dosimetry and Medical Radiation Physics Section, Division of Human Health, International Atomic Energy Agency, Physikalisch-Technische Bundesanstalt, National Metrology Institute, University of the Witwatersrand, Dosimetry and Medical Radiation Physics Section, Division of Human Health, International Atomic Energy Agency, National Research Council, Warren Alpert Medical School of Brown University

Abstract Preview: Purpose: The recently published IAEA-TRS-492 international code of practice (CoP) aims at improving traceability, accuracy, and consistency in Brachytherapy Dosimetry. To assess current approaches to ...

Applicability of Online Dose Measurement in Trilogy Linear Accelerators: Using Target Current Pulse Counting Method

Authors: Daming LI, Jinsen Xie, Zhe Zhang

Affiliation: Peking University Shenzhen Hospital Radiotherapy Department, School of Nuclear Science and Technology, University of South China

Abstract Preview: Purpose:
This study aims to investigate the feasibility of online dose measurement of the Trilogy linear accelerator output based on target current pulse signals.
Methods:
A data acquisition ...

Application of a Flashdiamond Detector Coupled to a Beam Current Transformer to Commission a Monte Carlo Model of a Ultra-High Dose Rate Electron Beam

Authors: Javier Chiasson, Dominique Guillet, Arthur Lalonde, Karim Zerouali

Affiliation: Universite de Montreal, Centre Hospitalier de l'Universite de Montreal

Abstract Preview: Purpose:
To validate a Monte Carlo (MC) model of a Ultra-High dose rate (UHDR) electron beam using a prototype flashdiamond (fD) detector coupled to an electrostatically shielded beam current trans...

Assessing the Feasibility of LD-V1 Film for Annual Kilovoltage Imaging Dose Measurements

Authors: Maria F. Chan, Seng Boh Gary Lim, Shih-Chi Lin, Dustin W. Lynch, Usman Mahmood, Jeonghoon Park

Affiliation: Department of Medical Physics, Memorial Sloan Kettering Cancer Center

Abstract Preview: Purpose: To explore the feasibility of using GafChromic LD-V1 film for annual imaging dose assessment across kV radiography, fluoroscopy, and cone beam computed tomography (CBCT) imaging protocols, as...

Auto-Beam Hold Validation for Varian Sgrt Identify 3.0 on Truebeam Linear Accelerators

Authors: Hongyu Jiang, Wangyao Li, Dima Soultan, Fen Wang, Jun Xu

Affiliation: Department of Radiation Oncology, University of Kansas Medical Center

Abstract Preview: Purpose: To validate the Auto-Beam Hold functionality via the MMI connection between Varian SGRT system IDENTIFY 3.0 and treatment linacs.
Methods: A treatment plan was created in the Eclipse TPS u...

BEST IN PHYSICS MULTI-DISCIPLINARY: Quantitative MRI Oximetry: Combining EPR and OE-MRI for Volumetric Mapping of Hypoxia in Tumors

Authors: Victor B. Kassey, Maciej M. Kmiec, Periannan Kuppusamy, Sergey V. Petryakov, Conner Ubert

Affiliation: Dartmouth College

Abstract Preview: Purpose: Tumor hypoxia—a state of reduced oxygen supply—is well known to affect treatment response, particularly in radiotherapy and chemotherapy. Oxygen-enhanced magnetic resonance imaging (OE-MRI) u...

BEST IN PHYSICS THERAPY: Impact of Local Tissue Oxygenation Level on the Flash Effect in Murine Skin

Authors: David J. Gladstone, P. Jack Hoopes, David I Hunter, Brian W Pogue, Jacob Pierce Sunnerberg, Armin Tavakkoli

Affiliation: Thayer School of Engineering, Dartmouth College, University of Wisconsin - Madison, Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Geisel School of Medicine, Dartmouth College

Abstract Preview: Purpose: The FLASH effect, characterized by normal tissue sparing under ultra-high dose rate (UHDR) radiation delivery, remains mechanistically unclear. This study investigated the relationship betwee...

Characterization of Commercially-Available Dosimeters and Prototype Diamond Detectors for Absolute Flash Dosimetry of Small-Field Pulsed Proton Beams

Authors: Ronald C Chen, Hao Gao, Nicolas Gerard, Harold Li, Yuting Lin, Jarrick Nys, Jufri Setianegara, Mark Szczepanski, Aoxiang Wang

Affiliation: 4Physikalisch-Technische WerkstÀtten (PTW), Department of Biomedical Engineering, Huazhong University of Science and Technology, Ion Beam Applications (IBA), Department of Radiation Oncology, University of Kansas Medical Center

Abstract Preview: Purpose: Modern synchrocyclotrons can produce magnetically-scanned protons at ultra-high dose-rates (FLASH). However, their pulsed nature leads to high doses-per-pulse (DPP) which can cause non-neglig...

Characterization of Novel Shielded and Unshielded Silicon Diode Detectors for Photon and Electron Dosimetry in Radiation Therapy

Authors: Mohamad Ahmad Alissa, Carson Brame, Damian Czarnecki, Olivier Evrard, Charbel A. Habib, Jeff Hildreth, Andy Murray, Andreas Schönfeld, Ann-Britt Schönfeld, David Towle, Gerd Wessing

Affiliation: CDT-West - Centrum fĂŒr Diagnostik und Therapie, Radiologie Vechta, Technische Hochschule Mittelhessen, MyMichigan Health, Sun Nuclear Corp., Mirion Technologies

Abstract Preview: Purpose: To characterize the performance of novel shielded and unshielded silicon diode detectors in relative photon and electron beam dosimetry.

Methods: The novel shielded and unshielded sili...

Characterization of a Prototype Flashdiamond Detector for Conventional and Uhdr Beams

Authors: Dominique Guillet, Arthur Lalonde, Bryan R. Muir, James Renaud, Karim Zerouali

Affiliation: Universite de Montreal, Centre Hospitalier de l'Universite de Montreal, National Research Council

Abstract Preview: Purpose:
To evaluate the dose rate dependence, beam quality dependence, and short-term stability of a novel flashDiamond (fD) prototype detector for conventional and ultra-high dose rate (UHDR) bea...

Characterization, Commissioning, and Clinical Evaluation of a Commercial Beo Optically Stimulated Luminescence (OSL) System

Authors: Brett G Erickson, Joseph P. Kowalski, Xinyi Li, Qiuwen Wu, Sua Yoo

Affiliation: Duke University, Mayo Clinic - Department of Radiation Oncology, Duke University Medical Center

Abstract Preview: Purpose: Characterization and commissioning of the BeO-based myOSLchip system was performed (per TG191) to assess its feasibility as a full replacement for the recalled Landauer aluminum oxide OSL in ...

Characterizing and Modeling Higher-Order Motions of Collimator Subsystem on a 60RPM Gantry Linac for Improved Small Target Dosimetry

Authors: David J. Carlson, Yiu-Hsin Chang, Huixiao Chen, Zhe (Jay) Chen, Blake Gaderlund, Ray Yang

Affiliation: RefleXion Medical, Department of Therapeutic Radiology, Yale University School of Medicine

Abstract Preview: Purpose: To address the root cause of dosimetric discrepancy for small central targets (<2cm) especially sensitive to geometric alignment of beamlets, by modeling higher-order oscillations of the coll...

Clinical Implementation of a Film Based Psqa System for SBRT on a 1.5T MR-Linac

Authors: Dylan Yamabe Breitkreutz, Lee Chin, Brige P. Chugh, Mark D'Souza, Brian M. Keller, Anthony Kim, Michelle K. Nielsen, Arjun Sahgal

Affiliation: Sunnybrook Health Sciences Centre

Abstract Preview: Purpose: The Elekta Unity MR-linac delivers highly conformal SBRT treatments using IMRT. These treatment plans require patient-specific quality assurance (PSQA) measurements to detect discrepancies be...

Combining Proton Flash and Spatially Fractionated Radiotherapy – Experimental and Simulation Based Dosimetric Characterization

Authors: Gulakhshan M Hamad, Sina Mossahebi, Yannick P. Poirier, Amit Sawant

Affiliation: University of Maryland School of Medicine, Maryland University Baltimore

Abstract Preview: Purpose:
The combination of ultra-high dose rate (UHDR) proton therapy, known for normal tissue sparing, with spatially-fractionated radiotherapy (SFRT), promising enhanced tumor control and tissue...

Commissioning Radcalc v7.3 with a Collapsed Cone Calculation Algorithm for 6X FFF and 10X FFF Energies

Authors: Maria Jose Almada, Carlos Bohorquez, Maximiliano Musso, Rosa Petit, Carlos Daniel Venencia, Lucy D. Wolfsberger

Affiliation: LAP, Instituto Zunino - Fundacion Marie Curie

Abstract Preview: Purpose:
PSQA is crucial in maintaining patient safety, typically depending on dosimetric measurements. However, advancements in computational technology have highlighted the growing significance o...

Commissioning a Fixed Beamline Ultra-High Dose Rate Proton Therapy System

Authors: Ahmet S. Ayan, Austin M. Faught, Eunsin Lee, Julia Pakela

Affiliation: Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Ohio State University, The Ohio State University

Abstract Preview: Purpose: To present commissioning of a fixed beamline ultra-high dose rate proton pencil beam scanning system, the world’s first multi-room Varian ProBeam360⁰
Methods: The fixed beamline pencil bea...

Commissioning of Varian HDR Surface Applicators Using High-Resolution Diode Array and Film Dosimetry

Authors: Milad BaradaranGhahfarokhi, Manuel A. Morales Paliza

Affiliation: Vanderbilt University Medical Center

Abstract Preview: Purpose: The purpose of this study was to commission Varian HDR surface applicators using a high-resolution diode array and film dosimetry. This work evaluates dosimetric characteristics of these appl...

Commissioning of a 3D-CRT Planning Software for a Machine with Only Flattening-Filter Free Energy

Authors: Michalis Aristophanous, Steven Blum, Laura I. Cervino, Antonio L. Damato, Karen Episcopia, Chi Huang, Shih-Chi Lin, Michelle K. Savacool

Affiliation: Department of Medical Physics, Memorial Sloan Kettering Cancer Center, Memorial Sloan Kettering Cancer Center

Abstract Preview: Purpose: Varian Ethos (Varian Medical Systems, Palo Alto, CA) is a 6 MV flattening-filter-free (FFF) only machine, posing a challenge in creating homogeneous dose distributions when using manual 3D-CR...

Comparative Evaluation of Spekpy for Kilovoltage Beam Quality Characterization

Authors: Chang Heon Choi, Yoonsuk Huh, Jin Jegal, Seonghee Kang, Jung-in Kim, Inbum Lee, Hyojun Park

Affiliation: Department of Radiation Oncology, Seoul National University Hospital

Abstract Preview: Purpose: This study evaluates SpekPy, a Python-based tool for modeling kilovoltage (kV) x-ray spectra, by comparing its calculated energy spectra, half-value layer (HVL), and air kerma with experiment...

Comparison of Cine Cardiac Magnetic Resonance (CMR) Imaging Performance: 0.6 T Versus 1.5 T, Is 0.6 T Fit for Purpose?

Authors: Jacinta E. Browne, Tzu Cheng Chao, Ajit Deveraj, Ece Ercan, Tim Leiner, Alessio Perazzolo, Michal Povazan, Jouke Smink, Camilla Vita, Spencer Waddle, Dinghui Wang

Affiliation: Università Cattolica del Sacro Cuore, Philips Healthcare, Mayo Clinic

Abstract Preview: Purpose:
In recent years, mid-field MRI has shown promise to meet the technical demands of cardiac imaging1. Mid-field strengths offer advantages to CMR due to shorter T1-relaxation times, lower sp...

Comprehensive Analysis of Plan Modulation in SRS/SBRT Plans: A Single Institution Study of 461 Cases

Authors: Yunfeng Cui, Will Giles, Xinyi Li, Ke Lu, Jennifer C. O'Daniel, Anna E. Rodrigues, Chunhao Wang, Lana Wang, Yibo Xie, Sua Yoo, Jingtong Zhao

Affiliation: Duke University, Duke University Medical Center

Abstract Preview: Purpose:
To establish quantitative measurement of plan modulation for SRS/SBRT treated with Volumetric Modulated Arc Therapy (VMAT) on C-arm LINACs.
Methods:
A total of 461 plans were analyze...

Comprehensive Commissioning of an O-Ring-Shaped Image-Guided Radiotherapy System with a Gimbal-Mounted Linear Accelerator

Authors: Tetsuo Fukuda, Hideaki Hirashima, Kohei Kawata, Yukako Kishigami, Takashi Mizowaki, Mitsuhiro Nakamura, Yohei Sawada, Maika Urago

Affiliation: Kyoto University, kyotoUnivercity, Hitachi high-tech, Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine, Kyoto University

Abstract Preview: Purpose: To present the comprehensive commissioning results of the O-ring shaped linac, OXRAY.
Materials and Methods: OXRAY enables a novel three-dimensional unicursal noncoplanar irradiation metho...

Cross Characterization of a 3D Gamma Camera and Ring Brachytherapy Applicator

Authors: Zachary R. Grelewicz, Kevin C. Jones, Yixiang Liao, Andrew Ogilvy, Julius V. Turian

Affiliation: Rush University Medical Center

Abstract Preview: Purpose: To demonstrate the accuracy and QA application of a time-resolved 3D gamma camera, we measured the path traversed by the Ir-192 High-Dose-Rate (HDR) brachytherapy source passing through a rin...

Deformable Scintillator Array Dosimetry for In Vivo Volumetric Dose and Dose-Rate Validation of Uhdr Proton Therapy

Authors: Petr Bruza, Megan Clark, David J. Gladstone, Joseph Harms, Anthony E. Mascia, Brian W Pogue, Roman Vasyltsiv, Zhiyan Xiao, Rongxiao Zhang, Yongbin Zhang

Affiliation: Cincinnati Children's Proton Therapy Center, University of Missouri, Dartmouth College, Thayer School of Engineering, Dartmouth College, Washington University in St. Louis, University of Wisconsin - Madison

Abstract Preview: Purpose: With developing FLASH trials requiring diligent delivery monitoring, current proton therapy in-vivo dosimetry (IVD) cannot provide comprehensive verification, including dose and dose-rate vol...

Design and Use of a Modified Commercial Phantom for Gamma Knife End-to-End Testing

Authors: Edward A. Opalko, Matthew B. Podgorsak, Dheerendra Prasad

Affiliation: Roswell Park Comprehensive Cancer Center

Abstract Preview: Purpose: To design a 3D printed insert for Varian’s SRS Head Phantom that allows for multi-planar film dosimetry and to evaluate its ability in end-to-end testing for Gamma Knife treatments.
Method...

Development of a High-Speed Digital Breast Tomosynthesis System with a Two-Dimensional Multiple X-Ray-Source Array

Authors: John M. Boone, Andrew M. Hernandez, Paul Schwoebel, Jeffrey H. Siewerdsen, Alejandro Sisniega, Wojciech B. Zbijewski

Affiliation: Johns Hopkins University, University of California, UT MD Anderson Cancer Center, University of New Mexico Albuquerque, UC Davis Health

Abstract Preview: Purpose: To significantly improve image quality relative to clinically deployed digital breast tomosynthesis (DBT) systems, which use a 1D acquisition geometry (an arc), with a 2D image acquisition ge...

Development of the First Benchtop X-Ray Flash System

Authors: Ruirui Dong, Gernot Echner, Peter Haering, Clarence King, Carlos Murillo, Gavin Poludniowski, Nicholas Sammut, Joao Seco, Steffen Seeber, Maria Francesca Spadea, Elpida Theodoridou

Affiliation: KIT, Department of Physics and Astronomy, Heidelberg University, Karolinska Institutet, DKFZ, University of Malta

Abstract Preview: Purpose:
The goal is to develop the first benchtop X-ray FLASH system based on a conventional small animal irradiator. The small animal irradiator will be modeled using a Monte Carlo toolkit for bo...

Direct in-Vivo Real-Time Singlet Oxygen Detection in Photofrin-Mediated Photodynamic Therapy (PDT) Using Multispectral Singlet Oxygen Dosimetry (MSOLD)

Authors: Theresa Busch, Robert H Hadfield, Madelyn Johnson, Baozhu Lu, Hongjing Sun, Brian C. Wilson, Weibing Yang, Timothy C. Zhu

Affiliation: University of Glasgow, University of Toronto, University of Pennsylvania

Abstract Preview: Purpose: Direct detection of singlet-state oxygen (ÂčO₂) is crucial for advancing type II photodynamic therapy (PDT), but its short lifetime makes in vivo measurement highly challenging. Although Photo...

Dose Rate Measurements of Scanning Carbon Ion Beams Using a Plastic Scintillator Detector

Authors: Motohiro Kawashima, Adrian Kugara, Masao Nakao, Shuichi Ozawa, Mutsumi Tashiro, Maria Varnava

Affiliation: Gunma University Heavy Ion Medical Center, Hiroshima High-Precision Radiotherapy Cancer Center

Abstract Preview: Purpose: This study aimed to evaluate the time-dependent dose rate characteristics of a scanning carbon ion beam using a fast-response plastic scintillator detector (PSD), with a focus on its potentia...

Dose Reconstruction from Prompt-Gamma Imaging Towards Real-Time Adaptive Proton Therapy

Authors: Thomas R. Bortfeld, Prof. Elisabetta De Bernardi, Tianxue Du, Beatrice Foglia, Chiara Gianoli, Takamitsu Masuda, Katia Parodi, Marco Pinto, Boon-Keng Kevin Teo, Yunhe Xie

Affiliation: Department Of Radiation Oncology, Massachusetts General Hospital (MGH), School of Medicine and Surgery, University of Milano-Bicocca, Department of Medical Physics, Ludwig-Maximilians-UniversitĂ€t MĂŒnchen (LMU Munich), Department of Medical Physics, Ludwig-Maximilians-UniversitĂ€t (LMU) MĂŒnchen, National Institutes for Quantum Science and Technology (QST), University of Pennsylvania, Department of Experimental Physics - Medical Physics, Ludwig-Maximilians-UniversitĂ€t (LMU) MĂŒnchen

Abstract Preview: Purpose: The full potential offered by protons in clinical practice is limited by range uncertainties. One possibility for monitoring is through secondary prompt gammas (PG). PG emission along the pen...

Dosex As a per-Pulse Uhdr and Conventional Electrometer Compatible with Sandard Clinical Probes

Authors: Petr Bruza, David J. Gladstone, Austin Sloop, Rongxiao Zhang

Affiliation: Thayer School of Engineering, Dartmouth College, Dartmouth Health

Abstract Preview: Purpose: UHDR-specific probes are becoming available on the market but often demand high costs and long order times. The reduced sensitivity of these probes often imposes challenges when measuring con...

Dosimeteric Parameter Evaluation of Digital Polycrystalline Semiconductor Dosimeters for Quality Assurance of High-Dose-Rate Brachytherapy

Authors: Woong Cho, Jin-Beom Chung, Moo-Jae Han, Sang Won Kang, Boram Lee

Affiliation: Department of Radiation Oncology, Seoul National University Boramae Medical Center, Department of Radiation Oncology, Seoul National University Bundang Hospital, Department of Radiation Oncology, Inha University Hospital

Abstract Preview: Purpose: This study aims to establish a digital quality assurance (QA) system for high-dose-rate (HDR) brachytherapy by evaluating self-developed polycrystalline semiconductor dosimeters (PSDs).
Me...

Dosimetric Characterization of Sun Nuclear EDGE Diodes in the Plateau Region of Proton Pencil Beam Scanning (PBS) Fields

Authors: Wesley S. Culberson, Ryan Gardner, Patrick M Hill, Mark Pankuch, Karsten K. Wake

Affiliation: Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin - Madison, Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin, Northwestern Medicine Proton Center

Abstract Preview: Purpose: To assess the dosimetric capabilities of Sun Nuclear (Melbourne, FL) EDGE Diode Detectorsℱ for measurements in the plateau region of pencil beam scanning (PBS) fields. Many clinical dosimeter...

Dosimetric Evaluation of Comprehensive Motion Management in 1.5T MR-Linac for Real-Time Gated Radiotherapy

Authors: Kin Yin Cheung, Chen-Yu Huang, Chi Wah Kong, Ka Ki Lau, Pei-Xiong Li, Pak Hang Nam, Mei Yan Tse, Jierong Wang, Bin Yang, Siu Ki Yu, Jing Yuan, Chi To Yung, Shang Peng Felix Yung

Affiliation: Medical Physics Department, Hong Kong Sanatorium and Hospital, Research Department, Hong Kong Sanatorium and Hospital

Abstract Preview: Purpose: Intrafraction motion management remains a major challenge in magnetic resonance-guided radiotherapy (MRgRT). The recent clinical release of an active motion management system aims to enhance ...

Dosimetric Evaluation of Enhanced Dynamic Leaf Gap Modeling in Small-Field Clinical Plans: A Verification Study

Authors: Ian J. Butterwick, Sumudu Katugampola, ChangSeon Kim, Evan G. Meekins, Zhengdong Zhang

Affiliation: Mount Sinai Beth Israel, Gesinger Medical Center, Geisinger Medical Center

Abstract Preview: Purpose: To evaluate the dosimetric impact of enhanced dynamic leaf gap (EDLG) modeling in Eclipse V18.0 on small-field dosimetry within VMAT plans.
Methods: Plans with small fields (1 cm x 1 cm to...

Dosimetry Calibration for Low-Energy Protons (2-4 MeV) Using Gafchromic Film Dosimeters

Authors: Michael Dingfelder, Homeira Faridnejad

Affiliation: East Carolina University, Department of Physics, East Carolina University

Abstract Preview: Purpose: To use Gafchromic film for measurement of the dose delivered by low-energy (2-4 MeV) protons to living cells.
Methods: Five different types of Gafchromic films were tested for dosimetry un...

Dosimetry Commissioning of a Commercial Cabinet X-Ray Irradiator for Small Animal Irradiation

Authors: Sang Hyun Cho, Amrit Kaphle, Sunil Krishnan, Neerajan Nepal

Affiliation: The University of Texas MD Anderson Cancer Center, The University of Texas Health Science Center

Abstract Preview: Purpose: To determine the basic dosimetry parameters and characteristics of a commercial cabinet x-ray unit for small animal irradiation as well as the specific dosimetry parameters for concurrent irr...

Dosimetry Impact of Beam Flatness on a Clinical Synchrocyclotron Proton System

Authors: Winter Green, Yao Hao, Nels C. Knutson, Matthew C. Schmidt, Xiandong Zhao

Affiliation: Washington University School of Medicine in St. Louis, Washington University School of Medicine, Department of Radiation Oncology, Washington University School of Medicine, WashU Medicine

Abstract Preview: Purpose: Beam profile flatness is crucial for both photon and proton radiotherapy systems. This work investigated the dosimetry impact of beam flatness on a clinical synchrocyclotron proton system.

Dynamic Winston-Lutz Testing for FFF Beams

Authors: Cambridge L Bui-Nguyen, Alexander S. Nguyen, Liqiang (Lee) Tao

Affiliation: Varian AOS @Epic Care, UC Berkeley

Abstract Preview: Purpose: Dynamic Winston-Lutz (WL) testing provides a comprehensive framework for evaluating the accuracy of isocenter alignment. This study investigates the impact of dynamic beam modulation, such as...

Establishing Tumor Size-Dependent Contrast Requirements for Multi-Target Biology-Guided Radiation Therapy (BgRT)

Authors: Muhammad Ramish Ashraf, Girish Bal, Daniel Pham, Murat Surucu

Affiliation: RefleXion Medical, Department of Radiation Oncology, Stanford University School of Medicine, Stanford University

Abstract Preview: Purpose: To determine minimum target size and FDG contrast thresholds for reliable Biology-guided Radiation Therapy (BgRT) delivery using a systematic phantom study.
Methods: A custom 3D-printed ph...

Establishing a Conventional Linac-Based Electron Flash Beam

Authors: Christopher Bartee, Justin Riley DeFrancisco, Marcos Feijoo, Siyong Kim, Tianjun Ma

Affiliation: Blue Physics LLC, Virginia Commonwealth University

Abstract Preview: Purpose: Irradiation with FLASH has been shown to decrease normal tissue toxicity while maintaining similar tumor control. To advance FLASH into the clinic, more preclinical investigations are first n...

Evaluation of Film and 3D Printed Patient-Specific Phantom for Minibeam Radiation Therapy (MBRT) Dosimetry

Authors: Darwin Abraham Garcia, Michael P. Grams, Scott C Lester, Maryam Mashayekhi, Douglas John Moseley, Robert W Mutter, Sean S Park, Chrystian Quintero Mateus

Affiliation: Mayo Clinic - Rochester, Mayo Clinic

Abstract Preview: Purpose: MBRT delivers sub-millimeter wide regions of high “peak” (~10s Gy) and low “valley” (~1 Gy) doses to treat cancer. MBRT commissioning is performed in flat, uniform plastic water. Thus, differ...

Evaluation of Four Different Dose Calculation Algorithms for Commissioning of a New Tyoe of Scanned Proton Therapy System

Authors: Nobukazu Fuwa, Masato Horita, Takahiro Kato, Ryo Tanokura, Yuki Tominaga

Affiliation: Medical Co. Hakuhokai, Osaka Proton Therapy Clinic, Central Japan International Medical Center, Department of Radiological Sciences, School of Health Sciences, Fukushima Medical University

Abstract Preview: Purpose:
We have installed a new type of scanned proton therapy system (Varian ProBeam 360°TM). This study aimed to evaluate the four different dose calculation algorithms.
Methods:
Sixteen b...

Evaluation of Ion Chamber Performance and Suitability for Flash Proton Therapy Dosimetry

Authors: Seohyeon An, Yoonsun Chung, Seonghoon Jeong, Seongmoon Jung, Chae-Eon Kim, In Jung Kim, Sung Hun Kim, Se Byeong Lee, Sang-il Pak, Jong In Park

Affiliation: POHANG ACCELERATOR LABORATORY, Hanyang University, Korea Research Institute of Standards and Science (KRISS), Ilsan Paik Hospital, National Cancer Center, National Cancer Center Korea, Korea Research Institute of Standards and Science

Abstract Preview: Purpose: To evaluate the performance of three ion chambers—Advanced Markus (AMC), PinPoint, and Roos—under FLASH proton beam conditions and assess the response of the nozzle monitor chamber for their ...

Evaluation of an Analytical Simulation Technique By Comparing Transmitted Spectra Against GEANT4 through a Hafnium-Loaded Heterogeneous Phantom

Authors: Sabrina Campelo, Sandun Y. Jayarathna, Adam D. Melancon, Paige L. Nitsch, Christopher Ryan Peeler, Julianne M. Pollard-Larkin, Ramaswamy Sadagopan, Xiaochun Wang, George Zhao

Affiliation: The University of Texas MD Anderson Cancer Center

Abstract Preview: Purpose: Development of an in-house analytical simulation for streamlining photon counting detector (PCD) system protocols through measuring transmitted photon energy spectra through a Hafnium (Hf)-lo...

Evaluation of the Hyperscint RP-200 Plastic Scintillation Dosimetry System for Reference Dosimetry in Ultra-High Dose Rate Electron Beam Therapy: A Comparative Study

Authors: Julie Colnot, Eric Deutsch, Christelle Huet, Danahé LeBlanc, Pauline Maury, Charlotte Robert, Imane Saïd Mansour, Cathyanne Schott, Francois Therriault-Proulx

Affiliation: INSERM U1030, Gustave Roussy, University Paris-Saclay, LDRI, IRSN, Medscint, THERYQ / INSERM U1030, Gustave Roussy, University Paris-Saclay, Université Paris-Saclay, Gustave Roussy, Inserm U1030, Radiothérapie Moléculaire et Innovation Thérapeutique

Abstract Preview: Purpose: FLASH radiotherapy, using ultra-high dose rates (UHDR, >100 Gy/s), spares healthy tissues while maintaining tumor control compared to conventional radiotherapy (CONV). However, UHDR dosimetry...

Feasibility of Commercial Independent-Dose-Calculation for Pencil-Beam-Scanning Proton Therapy

Authors: Wen C. Hsi, Kayla Schneider

Affiliation: Department of Radiation Oncology, University of Arkansas for Medical Sciences (UAMS), Department of Radiation Oncology, University of Arkansas for Medical Sciences

Abstract Preview: Purpose:
Measurement-based patient-specific quality-assurance (PSQA) conducted with a 2D dosimeter to verify delivered dose of each field over 3 measurement-depths is time-consuming with limited se...

Feasibility of Using a Dynamic-Platform with High-Resolution Patient-Specific QA Device for Periodic and Patient-Specific-QA in Respiratory-Gated Radiotherapy Lung SBRT Treatment

Authors: Tae Kyu Lee

Affiliation: Allina Health

Abstract Preview: Purpose: To assess the feasibility of a dynamic-platform integrated with high-resolution patient-specific-quality-assurance (PSQ device for periodic quality assurance (PQA) and PSQA in respiratory-gat...

Feasibility of a Normoxic N-Vinylpyrrolidone-Based Polymer Gel (VIPET) Dosimeter for Three-Dimensional Proton Beam Measurements

Authors: Yoshihiko Hoshino, Kenji Hotta, Taeko Matsuura, Ai Nakaoka, Hidenobu Tachibana

Affiliation: Hokkaido University, Department of Radiology, Gunma University Hospital, Radiation Safety and Quality Assurance Division, National Cancer Center Hospital East

Abstract Preview: Purpose: Gel dosimeters enable three-dimensional dose measurements, but no reports have evaluated the fundamental performance of VIPER-type gel dosimeters in proton beam measurements. Therefore, we ev...

First Beam Characterization of the Radiabeam FLEX-9 Electron Flash Linac

Authors: Robert Berry, John Buatti, Nathan Burger, Ryan T. Flynn, Greg Johns, Maksim Kravchenko, Sergey Kutsaev, Yen-Po Lee, Marcos Ruelas, Joel J. St-Aubin, Timothy J. Waldron

Affiliation: RadiaBeam Technologies, University of Iowa

Abstract Preview: Purpose: To report the factory acceptance tests of a preclinical linear accelerator, the FLEX-9 electron FLASH linac from RadiaBeam Technologies.
Methods: The FLEX-9 FLASH electron linac is designe...

First Phantom Testing of Biology-Guided Radiotherapy for Sequential Integrated Boost Radiotherapy

Authors: Girish Bal, David J. Carlson, Huixiao Chen, Zhe (Jay) Chen, Emily A. Draeger, Dae Yup Han, Henry S. Park

Affiliation: RefleXion Medical, Department of Therapeutic Radiology, Yale University School of Medicine

Abstract Preview: Purpose: This study explores the feasibility, accuracy, and dosimetric performance of hybrid biology-guided radiotherapy (BgRT) combined with image-guided radiotherapy (IGRT) for delivering sequential...

Free Radical Irradiation Emergent (FIRE) MRI: Real-Time MR-Based Quantification of Radiation-Produced Free Radical Generation on a Clinical MR-Linac

Authors: Claire Keun Sun Park, Atchar Sudhyadhom, Veena Venkatachalam, Noah Warner

Affiliation: Harvard–MIT Program in Health Sciences and Technology, Massachusetts Institute of Technology, Brigham and Women’s Hospital and Dana Farber Cancer Institute, Harvard Medical School,, Brigham and Women’s Hospital and Dana Farber Cancer Institute, Harvard Medical School

Abstract Preview: Purpose: Modern radiotherapy achieves sub-millimeter spatial accuracy but fails to account for patient- and spatially-specific variations in biological response. Free radical generation (FRG), particu...

Free-Breathing Spirometer-Gated Proton Pencil Beam Scanning Delivery Maintains Tumor Coverage with Improved Organ-at-Risk Sparing: A Motion Phantom Validation

Authors: Uriel Aura, Qing Chen, Arpit M. Chhabra, J Isabelle Choi, Chanda Guha, Meng Wei Ho, Sheng Huang, Minglei Kang, Stanislav Lazarev, Nancy Y Lee, Yang Lei, Haibo Lin, Hang Qi, Mahbubur Rahman, Charles B. Simone, Shouyi Wei, Irini Yacoub, Francis Yu, Anna Zhai, Ajay Zheng

Affiliation: DYN'R Medical System, New York Proton Center, Montefiore Medical Center and Albert Einstein College of Medicine, Icahn School of Medicine at Mount Sinai, Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, Tianjin Medical University Cancer Institute&Hospital, Department of Human Oncology, University of Wisconsin-Madison

Abstract Preview: Purpose: Managing tumor motion during pencil beam scanning proton therapy remains challenging. This study investigated the feasibility and dosimetric benefits of Free-Breathing Respiratory-Gated Deliv...

High Dose Rate Electron Beam Depth Dose Characterization

Authors: Fitria P Krisna, Mardon Limena, Supriyanto Ardjo Pawiro, Jhon H Saragih, Wahyu E. Wibowo, Poonam Yadav, Ummu M Zahro

Affiliation: Northwestern Memorial Hospital, Northwestern University Feinberg School of Medicine, Radiation Oncology Dr. Cipto Mangunkusumo National Central Public Hospital, Department of Physics, Mathematics and Natural Sciences, University of Indonesia, Department of Radiotherapy, Mandaya Hospital, Department of Radiation Oncology, Mitra Keluarga Kenjeran Hospital, Department of Radiotherapy, Mandaya Royal Hospital, Radiation Oncology, Santosa Hospital

Abstract Preview: Purpose: To perform depth dose characteristics of High Dose Electron Beam and utility of various commercially available detectors.
Methods: The measurements were performed using an Elekta Versa HD ...

High-Energy Current Detectors for Proton Dose-Rate Beam Monitoring at Flash Dose-Rates.

Authors: Davide Brivio, Lia Carroll, Juliane Daartz, Jan PO Schuemann, Piotr Zygmanski

Affiliation: Massachusetts General Hospital, Department of Radiation Oncology, Brigham and Women’s Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Massachusetts General Hospital and Harvard Medical School

Abstract Preview: Purpose: We employ High-Energy Current (HEC) detectors for real-time monitoring of proton beams at conventional to FLASH dose rates. This would help overcome the need for fast and accurate dosimeters ...

High-Fidelity Monte-Carlo Model Development and Validation of a 0.5T Bi-Planar Linac-MR Using Topas: Multileaf Collimator Modeling, Positioning, and Dose Verification in Slab Phantoms

Authors: B. Gino Fallone, Alireza Gazor, Andrei D. Ghila, Gawon Han, Patricia A. K. Oliver, Michael W. Reynolds, Keith D. Wachowicz, Tania Rosalia Wood, Shima Y. Tari, Eugene Yip

Affiliation: Medical Physics Division, Department of Oncology, University of Alberta, Nova Scotia Health, Dept. of Medical Physics and Dalhousie University, Dept. of Physics and Atmospheric Science, Dept. of Radiation Oncology, Dept. of Medical Physics, Cross Cancer Institute and Dept. of Oncology, University of Alberta; MagnetTx Oncology Solutions, www.magnetTX.com, Department of Medical Physics, Arthur J. E. Child Comprehensive Cancer Centre, Dept. of Medical Physics, Cross Cancer Institute and Dept. of Oncology, University of Alberta, Department of Medical Physics, BC Cancer, Medical Physics Division, Department of Oncology, University of Alberta and Department of Medical Physics, Cross Cancer Institute

Abstract Preview: Purpose: To develop and validate a high-fidelity Monte-Carlo (MC) model of a 0.5T bi-planar Linac-MR in TOPAS, focusing on accurate Multileaf Collimator (MLC) modelling and positioning for open apertu...

Hydrated Electron Yield Under Electron Irradiation at Ultra-High Dose Rates with Varying Physical Beam Parameters

Authors: Xu Cao, Wesley S. Culberson, Aubrey Parks, Brian W Pogue, Matthew Reed, William Scott Thomas

Affiliation: University of Wisconsin: Madison, Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin - Madison, University of Wisconsin-Madison, University of Wisconsin - Madison, UW-Madison

Abstract Preview: Purpose: Under Ultra-High Dose Rate (UHDR) irradiation, radical-radical interactions are likely enhanced due higher density production in time and space and this alters the cascade of reactions that s...

Image Guidance for Mitigating the Impact of Table Walkout on Delivered Dose in Non-Coplanar Stereotactic Radiotherapy

Authors: William E Burrell, Philip F. Durham, Anne N Hubbard, Yohan Akeakamai Walter, Hsinshun Terry Wu

Affiliation: Willis Knighton Cancer Center

Abstract Preview: Purpose: Linear accelerator (LINAC)-based single-isocenter, multi-target (SIMT) treatment has streamlined the stereotactic radiosurgery (SRS) workflow. However, off-isocenter treatment carries multipl...

Imaging Based Surveys to Identify Leaks and Gaps in Radioisotope and Fluoroscopic x-Ray Shielding Barriers for Improved Shielding of Hospital Workers.

Authors: Nicholas Borges, Steven Brown, Jerimy C. Polf

Affiliation: H3D, inc, Massachusetts General Hospital, M3D, Inc

Abstract Preview: Purpose: To evaluate the potential of using real-time imaging and dose measurement to find weak spots and leaks in bedside shielding systems during diagnostic or interventional fluoroscopic procedures...

Impact of Breathing Trace on Gating Uncertainty

Authors: William P. Donahue, Lauren Smith, Shu (Stella) Xing

Affiliation: Department of Medical Physics, Memorial Sloan Kettering Cancer Center

Abstract Preview: Purpose: To quantify the dosimetric uncertainty of end-exhale gating as a function of breathing pattern.

Methods: A Truebeam delivered AP square fields to EBT4 film placed in the Quasar MRI4D M...

Impact of Source-to-Imager Distance on Patient-Specific Quality Assurance Using Epid

Authors: Hajee Reyaz Ali Sahib, Sangeeta Hazarika, Muthukumaran Manavalan, Jaswin Raj, Daya Nand Sharma, Seema Sharma, Subramani Vellaiyan

Affiliation: AIIMS NCI Jhajjar, PTW North America Corporation, All India Institute of Medical Sciences

Abstract Preview: Purpose:
Purpose is to investigate the effect of extended source-to-imager distances (SID) on the resolution of VMAT patient-specific quality assurance (PSQA) in portal dosimetry (PD).
Methods:<...

In Vivo Measurements of Hydrated Electron Production with an Ultra-High Dose Rate (UHDR) Electron Beam

Authors: Xu Cao, Wesley S. Culberson, Aubrey Parks, Brian W Pogue, William Scott Thomas

Affiliation: Department of Medical Physics, School of Medicine and Public Health, University of Wisconsin - Madison, University of Wisconsin-Madison, University of Wisconsin - Madison, UW-Madison

Abstract Preview: Purpose:
The hydrated electron is a critical reactive species generated during the radiolysis of water when ionizing radiation interacts with biological tissues. It plays a pivotal role in mediatin...

Innovative Design and Simulation of a Pediatric-Dedicated SPECT: Enhancing Imaging Performance for a Healthier Scans in Children

Authors: Mohammadreza Ay, Nahal Daneshgar, Nima Kasraie, Abbas Monsef, Zeinab Peymani, Hadi Rezaei, Peyman Sheikhzadeh

Affiliation: University of Minnesota Medical School, Radiation Oncology, Department of Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, Shiraz University of Medical Sciences, Department of Medical Physics, Tehran University of Medical Sciences, Department of Medical Physics and Biomedical Engineering, UT Southwestern Medical Center, Imam Khomeini Hospital Complex,Tehran University of Medical Sciences

Abstract Preview: Purpose:
This study aims to design and simulate an innovative pediatric-dedicated SPECT scanner optimized for children’s unique anatomical and safety needs by enhancing sensitivity in data acquisit...

Interplay of Relative Biological Effectiveness and Dose Rate in Eye Plaque Brachytherapy with Low Energy Photons

Authors: Alexei V. Chvetsov, Sunan Cui, Sunyoung Jang, Robert D. Stewart

Affiliation: University of Washington and Fred Hutchinson Cancer Center, Penn State College of Medicine, University of Washington

Abstract Preview: Purpose: To evaluate spatial variation of relative biological effectiveness (RBE) in COMS (Collaborative Ocular Melanoma Study) eye plaques with low energy 125I and 103Pd photon sources as a function ...

Investigating the Effect of Beam Flattening Filter on Dose Estimated with Varian’s Original and Enhanced Mlc Models

Authors: Kenny Guida, Hongyu Jiang, Harold Li, Hem Bahadur Moktan Tamang

Affiliation: University of Nebraska Medical Center, Department of Radiation Oncology, University of Kansas Medical Center

Abstract Preview: Purpose: Varian Eclipse v18.0 introduced Enhanced Leaf Model (ELM) of MLC, which provides better dose calculation accuracy than original DLG-based MLC model. The leaf-gap (LG) parameter for ELM repres...

Investigating the Radiation Chemistry of Flash Radiation Therapy through Electron Paramagnetic (EPR) Spectroscopy

Authors: Ramin Abolfath, Alexander Baikalov, Stefan Bartzsch, Nolan M. Esplen, Alan Eduardo Lopez Hernandez, Emil Schueler

Affiliation: MD Anderson Cancer Center, PI Experimental Medical Physics, Institute of Radiation Medicine (IRM), Helmholtz Munich, Germany, Howard University, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center

Abstract Preview: Purpose: FLASH radiation therapy (FLASH-RT) leverages ultra-high dose rates (UHDR) to spare normal tissue as compared to conventional (CONV)-RT while preserving tumor control; this is termed the FLASH...

Just-in-Time Quality Assurance Check for Yttrium-90 Radioembolization Therapy

Authors: Stewart J. Becker, Andrew Genuit, Mariana Guerrero, Yannick P. Poirier

Affiliation: University of Maryland School of Medicine, Department of Radiation Oncology, University of Maryland School of Medicine

Abstract Preview: Purpose: To introduce an additional quality assurance step to prevent human error in vial mix-ups during Yttrium-90 (Y90) radioembolization by verifying the local assay at the time of delivery. We pro...

Log File-Based Patient-Specific QA As a Viable Alternative to Measurement-Based QA in IMPT

Authors: Sina Mossahebi, Pouya Sabouri, Kayla Schneider, James W Snider

Affiliation: University of Maryland School of Medicine, Proton International, Department of Radiation Oncology, University of Arkansas for Medical Sciences (UAMS), Department of Radiation Oncology, University of Arkansas for Medical Sciences

Abstract Preview: Purpose:
Conventional patient-specific QA (PSQA) for intensity-modulated proton therapy (IMPT) requires extensive measurements, straining resources in single-room proton centers. This study evaluat...

Modernization of the NIST Air-Kerma Strength Standard for LDR Brachytherapy Seeds

Authors: Michael G. Mitch, Csilla I. Szabo-Foster

Affiliation: National Institute of Standards and Technology

Abstract Preview: Purpose: The U.S. air-kerma strength standard for low-dose-rate (LDR) low-energy photon-emitting brachytherapy sources provides measurement traceability for calibrations at the AAPM Accredited Dosimet...

Monitor Unit (MU) Substructure Analysis for Low MU Deliveries

Authors: Indra J. Das, Ahtesham U. Khan, Andrew J. White, Poonam Yadav

Affiliation: Northwestern Memorial Hospital, Northwestern University Feinberg School of Medicine

Abstract Preview: Purpose: During intensity modulated radiotherapy (IMRT) planning, low MU segments (< 3 MU) are commonly avoided due to documented dosimetric nonlinearity and poor reproducibility. This work aims to ex...

Monte Carlo Evaluation of Water-Equivalent Materials for Nanowire-Based Oslds in Flash Radiotherapy

Authors: James Chun Lam Chow, Harry E Ruda

Affiliation: University of Toronto, Princess Margaret Cancer Centre

Abstract Preview: Purpose: FLASH radiotherapy (FLASH-RT) with dose rate greater than 40 Gy/s, has demonstrated potential in reducing normal tissue toxicity while maintaining tumor control. However, accurate and reliabl...

Monte Carlo Simulation and Dosimetric Verification of 3D Range Modulators for a Multi-Field-Optimization Flash-IMPT Plan

Authors: Michael M Folkerts, Miriam Krieger, Pierre Lansonneur, Gerard Paquet, Petar Penchev, Christoph Schuy, Yuri Simeonov, Uli Weber, Klemens Zink

Affiliation: GSI Helmholtzzentrum fuer Schwerionenforschung, Institute of Medical Physics and Radiation Protection (IMPS), University of Applied Sciences, Varian Medical Systems

Abstract Preview: Purpose:
Ultra-high dose-rate proton irradiation may spare the healthy tissue (FLASH-effect). The 3D-range-modulator (3D-RM) method reduces the treatment time compared to conventional IMPT and can ...

Moving Away from Measuring Everything - Implementing 3D Recalculation in a Large Networked Radiotherapy Institution to Replace Routine IMRT / VMAT QA

Authors: Eujin Chan, Christopher Colyer, Leon F Dunn, Jonathan Dunning, Michael Grace, Onno Kamst, Alex Livingstone, Thulani Nyathi, Vladimir Sashin, Philip Satory, Hilmar Schachenmayr, Brindha Subramanian, Lindsay J. Tremethick, Luke Webb

Affiliation: GenesisCare

Abstract Preview: Purpose: The purpose of this work is to outline the methodology and results from the implementation of a 3D recalculation software to replace IMRT/VMAT PSQA measurement across a large, networked radio...

Off-Axis Dependency of the Sun Nuclear MapCheck3 Diode Array

Authors: Alyssa Gadsby, William J. Godwin, Daniel G. McDonald, Jean L. Peng, Alek K. Rapchak, Sean A Roles, Austin M. Skinner, Stephanie Tan

Affiliation: Medical University of South Carolina

Abstract Preview: Purpose: The Sun Nuclear MapCheck3 device is used for patient-specific QA. While it is typically employed in perpendicular field-by-field delivery using the Isocentric Mounting Fixture, fields not ful...

Performance Evaluation of End-of-Life Epid Panel Utilizing Automated Quality Assurance Test Suite

Authors: Michael Paul Barnes, Lana C. Critchfield, John J. DeMarco, Ellie Durussel, Nilendu Gupta, James Irrer, Peyton Jensen, Grace Gwe-Ya Kim, Cory S. Knill, Seng Boh Gary Lim, Justin K. Mikell, Jean M. Moran, Seyyedeh Azar Oliaei Motlagh, Mario Perez, Michael Pillainayagam, Claire Zhang

Affiliation: University of Michigan, Department of Radiation Oncology, University of Michigan, Department of Medical Physics, Memorial Sloan Kettering Cancer Center, Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Washington University School of Medicine in St. Louis, University of California San Diego, Royal North Shore Hospital, Calvary Mater Hospital Newcastle, Cedars-Sinai Medical Center

Abstract Preview: Purpose: EPIDs are widely used in linac QA due to their efficiency and accuracy. As EPIDs age, performance degradation may occur, potentially compromising reliability of EPID-based automated QA result...

Performance of Photon Counting Detector in a Clinical PCD-CT: A Novel Image-Based Evaluation

Authors: Frank F. Dong, Megan C. Jacobsen, Ke Li, Xinming Liu, John Rong

Affiliation: UT MD Anderson Cancer Center

Abstract Preview: Purpose: We aimed to understand the physical performance of a CdTe PCD-based detector system within a whole-body PCD-CT scanner, with the goal of optimizing its clinical application. Instead of relyin...

Precise Measurement of Leaf Open Time in Tomotherapy Using Advanced Plastic Scintillators

Authors: Marcos Feijoo, Mamoru Ichiki, Tatsuya Maeda, Tatsuhiro Makino, Tomonori Megumi, Tadashi Nakabayashi, Yukino Nakata, Shuichi Ozawa, Daishi Takayama

Affiliation: Hiroshima High-Precision Radiotherapy Cancer Center, Blue Physics LLC, Imamura General Hospital, Accuray Inc.

Abstract Preview: Purpose: This study aims to accurately measure the leaf open time (LOT) of the multi-leaf collimator (MLC) in tomotherapy using an advanced plastic scintillator detector (PSD) with high time resolutio...

Prior-Informed Neural Super-Resolution Dosimetry for Radiotherapy QA from Sparse Dosimeter Arrays

Authors: Muhammad Ramish Ashraf, Clinton Gibson, Gregory Szalkowski, Lei Wang, Siqi Wang, Lei Xing

Affiliation: Department of Radiation Oncology, Stanford University, Department of Radiation Oncology, Stanford University School of Medicine, Stanford University

Abstract Preview: Purpose: To develop a neural network-based super-resolution framework for enhancing the resolution of sparse dosimetry measurements in patient-specific radiotherapy QA. Sparse detector arrays, such as...

Remote Evaluation of Flash Beamlines for Electron, Proton, and MV Photons

Authors: Alexander Baikalov, Luke Connell, Nolan M. Esplen, Michele M. Kim, Stephen F. Kry, Emil Schueler, Hayden Scott, Ryan Sun, Paige A. Taylor, Uwe Titt

Affiliation: The University of Texas MD Anderson Cancer Center, University of Pennsylvania, UT MD Anderson Cancer Center, Department of Radiation Physics, The University of Texas MD Anderson Cancer Center

Abstract Preview: Purpose: to develop an affordable, portable device for accurately measuring FLASH dose rates from protons, electrons, and photons. 4 detectors were utilized to measure the temporal structure of proton...

Spot Map Modification for Planning Optimization on a Spot Scanning Proton System with Adaptive Aperture

Authors: Austen N. Curcuru, Winter Green, Yao Hao, Jiayi Liu, Yuting Peng, Tiezhi Zhang, Xiandong Zhao

Affiliation: Washington University School of Medicine, Department of Radiation Oncology, WashU Medicine, Virginia Commonwealth University, Washington University School of Medicine, Washington University in St. Louis

Abstract Preview: Purpose: We proposed a treatment planning optimization method that utilizes customized spot map modification to achieve less dosimetry uncertainty, monitor unit ratio (MUR) and neutron dose in a spot ...

Streamlined Stereotactic Radiosurgery (SRS) Commissioning Experience with a 6FFF Beam for an Elekta Versa: A Clinical Overview for Increased Precision.

Authors: Asma Amjad, Slade J. Klawikowski, Natalya V. Morrow, Haidy G. Nasief, Eric S. Paulson, An Tai, Hualiang Zhong

Affiliation: Department of Radiation Oncology, Medical College of Wisconsin

Abstract Preview: Purpose: Accurate and precise linac-based SRS commissioning can be very challenging. Thus, it is important to increase the confidence in the measurement at each step prior to end-to-end testing. The p...

Temporal Drift in Ir-192 Source Strength Measurements: A Braphyqs Multi-Center Analysis

Authors: Åsa K. Carlsson Tedgren, Taran Hellebust, Antonio Herreros, Jacob Johansen, Christian Kirisits, Panagiotis Papagiannis, Mark J. Rivard, Frank-Andre Siebert, Frank Verhaegen, Javier Vijande, Jan Wiersma, Marisol de Brabandere, Ruud van Leeuwen

Affiliation: UKSH, Campus Kiel, Klinik fĂŒr Strahlentherapie (Radioonkologie), Department of Oncology, The Norwegian Radium Hospital, Oslo University Hospital, Radiation Physics, Department of Medicine and Health (IMH), Linköping University, Radiation Oncology Department, Hospital ClĂ­nic-Universitat de Barcelona, IDIBAPS, IFIC-UV, Radiation Oncology, Amsterdam UMC location University of Amsterdam, Department of Radiation Oncology, Radboud University Medical Center, Department of Oncology, Aarhus University Hospital, University Hospital Gasthuisberg, Dept. of Radiation Oncology, Medical Physics Laboratory, Medical School, National and Kapodistrian University of Athens, Department of Radiation Oncology (MAASTRO), GROW – School for Oncology and Reproduction, Maastricht University Medical Centre+, Department of Radiation Oncology, Comprehensive Cancer Center, Medical University of Vienna, Warren Alpert Medical School of Brown University

Abstract Preview: Purpose: This study, which was carried out by the GEC-ESTRO BRAPHYQS working group, reports the increasing divergence between clinical reference air kerma rate (RAKR) measurements and vendor-provided ...

Treatment Dose Reconstruction of Digitized Deliveries on Reflexion X1 System Based on Megavoltage Imager and Dose Monitor Chamber

Authors: Angela J Da Silva, Andrew Groll, Gopinath Kuduvalli, Thomas Laurence, David W. Meer, Manoj Narayanan, Mingshan Sun, Don Vernekohl, Ray Yang

Affiliation: RefleXion Medical

Abstract Preview: Purpose: To implement post-treatment review of delivered dose fractions on RefleXion X1 accounting for independent detection of transmitted beamlets and transient dose fluctuations of individual pulse...

Two's Company, Three's a Crowd? a Bayesian Approach to Optimizing the Number of Measurement Readings in Radiation Therapy QA

Authors: Siyong Kim, Ava Paek, Joseph B. Schulz, James J. Sohn, Eric D. Stolen, Ethan D. Stolen

Affiliation: Department of Radiation & Cellular Oncology, University of Chicago, University of Central Florida, Virginia Commonwealth University, Department of Radiation and Cellular Oncology, University of Chicago, Department of Radiation Oncology, Stanford University School of Medicine

Abstract Preview: Purpose: The American Association of Physicists in Medicine Task Group 142 (AAPM TG-142) guidelines recommend three measurements during monthly quality assurance to keep results within two standard de...

Using a-Si 1200 Epid Portal Dosimetry for VMAT Commissioning

Authors: Ryan Burri, Nazanin Hoshyar, Jerry W. McCoy, Yulin Song, Huma Syed

Affiliation: Bay Pines VA Medical Center

Abstract Preview: Purpose: The study aimed to streamline traditionally manual, iterative, and time-consuming VMAT commissioning process. The goal was to identify an optimal set of MLC dosimetric parameters that minimiz...

Validation of a Pharmacokinetic Model for Dosimetry in Nuclear Medicine

Authors: Farhad Jafari, Brandon Hai Nguyen

Affiliation: Department of Radiation Oncology, University of Minnesota Medical School, Department of Radiology, University of Minnesota

Abstract Preview: Purpose: To validate a bottom-up approach to dosimetry in nuclear medicine.

Methods: A pharmacokinetic model is developed to represent the flow of activity between different compartments of the...

Visualization of Irradiation Field in Carbon-Ion Therapy By Openpet: Preliminary Analysis of Clinical Data

Authors: Go Akamatsu, Hiroaki Ikawa, Yuma Iwao, Han Gyu Kang, Masashi Koto, Hideyuki Mizuno, Akram Mohammadi, Makoto Shinoto, Minoru Tajiri, Hideaki Tashima, Chie Toramatsu, Taiga Yamaya

Affiliation: National Institutes for Quantum Science and Technology

Abstract Preview: Purpose: In-beam positron emission tomography (PET), in which positron emitters produced through fragmentation reactions are visualized, is a practical method for range verification in particle therap...

dosimetric Characterization of Tungsten Eye Shields Using Monte Carlo Simulation

Authors: Omer Abdulaziz Ali, Robin Hill, Nathan Huntelerslag

Affiliation: Waikato Hospital, Hamilton, New Zealand, Central Coast Cancer Centre, Gosford, Australia

Abstract Preview: Purpose: Characterizing transmission through eye shields is essential to understanding dose distribution in underlying tissues. This study aims to utilize Monte Carlo (MC) simulations to model and cha...

“You Can’t Unsee It”: Clinical Scintillation Imaging Enables First Localized Comparison between In Vivo dosimetry Measurements and the Treatment Plan

Authors: Petr Bruza, Megan Clark, David J. Gladstone, Lesley A Jarvis, Allison Matous

Affiliation: Thayer School of Engineering, Dartmouth College, Dartmouth Cancer Center, Dartmouth Health

Abstract Preview: Purpose: In vivo dosimetry (IVD) is underutilized, in part, because measured point doses cannot be accurately localized to the patient or treatment planning system (TPS), complicating the clinical and...