Search Submissions 🔎

Results for "axis positions": 23 found

Accuracy Assessment of Bragg Peak Imaging Using Protoacoustics at a Clinical Dose

Authors: Michael Caulfield, Ye Chen, Yoshihiro Ishi, Yasutoshi Kuriyama, Taeko Matsuura, Naoki Miyamoto, Taichi Murakami, Tomonori Uesugi, Kohei Yokokawa

Affiliation: Hokkaido University, Kyoto University, University of Alberta

Abstract Preview: Purpose: Protoacoustics has the potential for real-time and direct imaging of the Bragg peak. This study investigated the accuracy of the Bragg peak imaging based on the water phantom experiment at a ...

Calibration of Dynamic Collimation System Trimmers to Proton Beam Axis Using Gantry-Angle-Specific Corrections: A Look-up Table Solution

Authors: Wesley S. Culberson, Albert Du, Ryan T. Flynn, Ryan Gardner, Alonso N. Gutierrez, Patrick M Hill, Daniel E. Hyer, 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, University of Iowa, Iowa Health Care

Abstract Preview: Purpose: In proton therapy, the substantial size of the gantry introduces sag, causing the proton isocenter to drift as a function of gantry angle. While the scanning magnets correct the beam’s isocen...

Compact Representation of External Beam Photon Phase Space Data Via Implicit Neural Representation Learning

Authors: Serdar Charyyev, Cynthia Fu-Yu Chuang, Veng Jean Heng, Lianli Liu, Lei Xing, Yong Yang

Affiliation: Department of Radiation Oncology, Stanford University

Abstract Preview: Purpose: To replace large finite-size photon phase space files with a compact neural network capable of generating an infinite number of particles.
Methods: Three separate models were developed to ...

Comparison of Mlc Off-Axis Characteristics for Eclipse AAA v18 and v16 Using Portal Dosimetry

Authors: Junsheng Cao, Khushdeep Singh

Affiliation: Overlook Medical Center

Abstract Preview: Purpose: Eclipse v18 introduces Enhanced Leaf Modeling for MLCs. This study investigates the MLC off-axis characteristics using portal dosimetry
Methods:
MLC characteristics were analyzed for th...

Computational Prototype Single-Channel Vaginal Cylinder with Integrated Filter to Address Dose Uniformity in High-Dose-Rate Brachytherapy for Endometrial Cancer

Authors: Brett Bocian, Patrick James Jensen, Luis Augusto Perles, Christopher J. Tien

Affiliation: Yale University School of Medicine, University of Miami, The University of Texas MD Anderson Cancer Center, UT MD Anderson Cancer Center

Abstract Preview: Purpose: Guidelines for dose prescriptions in endometrial cancer are based upon depth from the cylinder, traditionally 5 mm or 0 mm (i.e., surface). There are no current single-channel vaginal cylinde...

Design and Testing of a 3D-Winston-Lutz Phantom to Quantify Isocentricity of Pencil Beam Scanning Proton Therapy Machines

Authors: Imad M. Ali, Nesreen Alsbou, Baraa Kalani

Affiliation: Oklahoma State University, University of Central Oklahoma, University of Oklahoma Health Sciences Center

Abstract Preview: Purpose: To develop a three-dimensional Winston-Lutz phantom to quantify the isocentricity of the gantry, couch, and on-board imager of the MEVION-S250i proton therapy machine.
Methods: A 3D-scinti...

Determine the Isocenter and Its Size for MR Linac Unity Part1: (U V) of Cax

Authors: Ting Chen, Siming Lu, Tanxia Qu, Hesheng Wang

Affiliation: NYU Langone Health

Abstract Preview: Purpose: This study, the first in a two-part series, aims to determine the isocenter position and size for the MR Linac UNITY, focusing on the central axis (CAX) alignment of its Multi-Leaf Collimator...

Determine the Isocenter and Its Size for MR Linac Unity Part2: (u v) of BB and Isocenter Position and Size

Authors: Tanxia Qu, Hesheng Wang

Affiliation: NYU Langone Health

Abstract Preview: Purpose:
This study, the second in a two-part series, evaluates the isocenter position (the point in 3D space minimizing the sum of Euclidean distances to the MLC's central axis) and isocenter size...

Development of a Novel Deformable Pelvis Phantom to Support Upright Applications

Authors: Adam P. Berdusco, Matthew R. Ceelen, Renata Farrell, Carri K. Glide-Hurst, Will Martin, Charles F. Maysack-Landry, Morgan A. McGauley, James Rice, Jordan M. Slagowski, Yuhao Yan

Affiliation: Departments of Human Oncology and Medical Physics, University of Wisconsin-Madison, University of Wisconsin - Madison, Department of Human Oncology, University of Wisconsin-Madison

Abstract Preview: Purpose: Upright radiotherapy (RT) is now available although this novel vertical CT and positioner presents unique challenges for quality assurance and testing methodologies. We have designed and buil...

Developments of a Low-Cost Multi-Target Winston-Lutz Phantom and Software for SRS Linac Machines

Authors: Nellie Brovold, Wenbo Gu, Huan Amanda Liu, Lin Ma

Affiliation: University of Pennsylvania, Mayo Clinic

Abstract Preview: Purpose: To develop a low-cost comprehensive QA phantom and software for single-iso multi-target SRS Linac machines. This phantom can perform 1) Winston-Lutz QA test for on-axis and off-axis targets, ...

Evaluating Target Isocenter Accuracy in Off-Isocenter Treatments Using an Extended Winston-Lutz Test

Authors: Maria de la Luz De Ornelas, Yunze Yang

Affiliation: University of Miami

Abstract Preview: Purpose:
An extended Winston-Lutz test (EWL), also known as off-axis Winston-Lutz, was performed to assess the linear accelerator’s (linac) deviations at isocenter and five off-iso targets. The imp...

Evaluation of the Isopoint System for Coincidence of Radiation and Physical Isocenter Checks of Linear Accelerators

Authors: Peter Balter, Thomas Alexander Cuthbert, Weiliang Du, Song Gao, Nicholas Zacharopoulos

Affiliation: Aktina Medical Corp, The University of Texas MD Anderson Cancer Center

Abstract Preview: Purpose: The purpose of this study is to evaluate the accuracy and reproducibility of a commercial product for verifying the size, location, and coincidence of physical isocenter (P_iso) and radiation...

Impact of Tracking By Jaws or Mlc on Treatment Accuracy in Synchrony Modality for Tomohelical Technique

Authors: Mireille Conrad, Cédric De Marco, Marie Fargier-Voiron, Maud Jaccard, Oscar Matzinger, Anthony Nagy, Stéphane Nevesny, Nicolas Joel Lionel Perichon

Affiliation: Clinique De Genolier

Abstract Preview: Purpose: Real-time tracking is implemented on Radixact by detecting the target position with 2D-kV image either directly (for lung tumors), or indirectly (using fiducials as surrogates), and by adapti...

In-Vivo Dosimetry in Positron-Guided Radiation Therapy

Authors: Davide Brivio, Erno Sajo, Ryan Williams, Piotr Zygmanski

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

Abstract Preview: Purpose: To develop a non-invasive 3D in-vivo dosimetry tool exploring the relationship between positron annihilations and dose per voxel using Monte Carlo simulation. The Positron Guided Radiation Th...

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...

Investigation of Prompt Gamma Imaging Using a Three Axis Rotating Compton Camera

Authors: Molokotima Kekana, Dennis S. Mackin, Stephen W. Peterson, Jerimy C. Polf

Affiliation: Department of Physics, University of Cape Town, M3D, Inc, The University of Texas MD Anderson Cancer Center, Houston

Abstract Preview: Purpose: To study the imaging characteristics of a prototype prompt gamma (PG) imaging system consisting of multiple rotating Compton cameras (CC).

Methods: The prototype CC imaging system is c...

Modeling of Novel Converging Beam Radiotherapy System in Geant4 Montel Carlo Simulation

Authors: Dirk A Bartkoski, Leonard Che Fru, Benjamin Abraham Insley, Michael Kleckner, Dongyeon Lee, Reza Reiazi, Mohammad Reza Salehpour, Aviad Schori, Ramesh C. Tailor

Affiliation: Empyrean Medical Systems, The University of Texas MD Anderson Cancer Center, Convergent-RnR, The University of Texas, MD Anderson, Houston TX

Abstract Preview: Purpose: A Geant4-based model was created for a G4BraggReflection process to simulate radiation transport within a novel radiotherapy system developed by Convergent Radiotherapy and Radiosurgery (CRnR...

Objective Verification of Mechanical and Radiation Isocenters Independent of Setup

Authors: Jonathan Dowell, Wei Luo, Shane McCarthy, Janelle A. Molloy, Markus Murphy

Affiliation: University of Kentucky, Department of Radiation Medicine, Iridesce Solutions, Inc.

Abstract Preview: Purpose: The novel machine quality assurance (QA) device nĂŒFilm (Iridesce Solutions, Lexington KY) allows for an objective assessment of light and radiation fields independent of setup. Herein, the ab...

Off- Axis Winston Lutz on C-Arm Linac Using in-House Phantom

Authors: Colton Baley, Bhuvaneswari Narayanan, Niko Papanikolaou, Daniel L. Saenz

Affiliation: UT Health San Antonio, Texas Oncology, University of Texas HSC San Antonio

Abstract Preview: Purpose: To evaluate the accuracy of off-axis winston lutz (WLT) for linac based stereotactic radiosurgery (SRS) treatments using in-house phantom.

Methods: Traditional WLT that uses cone and s...

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...

Tactile Image Prototype for Interpretation of Medical Images

Authors: Lily Jo Bertemes, Careesa Billante, Ashley Cetnar, Maximilian Stephen Meineke, Runhe Tan

Affiliation: The Ohio State University James Cancer Hospital, The James Cancer Center, The Ohio State University, The Ohio State University - James Cancer Hospital

Abstract Preview: Purpose: As accessibility is becoming a topic of increasing importance, we can consider how to make medical physics more accessible to those with various disabilities, including those with visual impa...

The Development of a Novel Biomechanical Model for Accurate Contour Deformation during Online Adaptative Metastatic Bone Cancer Radiotherapy Planning.

Authors: Jeremy S. Bredfeldt, Benito De Celis Alonso, Braian Adair Maldonado Luna, Kevin M. Moerman, Gerardo Uriel Perez Rojas, René Eduardo Rodríguez-Pérez, Kamal Singhrao

Affiliation: Department of Radiation Oncology, Brigham and Women's Hospital, Harvard Medical School, Department of Radiation Oncology, Brigham and Women's Hospital, Dana Farber Cancer Institute, Harvard Medical School, Department of Mechanical Engineering, University of Galway, Faculty of Physics and Mathematics, Benemérita Universidad Autónoma de Puebla

Abstract Preview: Purpose: Online adaptive radiotherapy replanning for single-isocenter bone cancer metastasis treatment reduces on-table treatment time and patient discomfort compared to the multi-isocenter standard-o...

Transformations of the Coordinate System for Monte Carlo Dose Calculations of Spot Scanning Proton Therapy

Authors: Hongyu Jiang

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

Abstract Preview: Purpose: This study presents a method for transforming coordinates from RayStation’s treatment planning system into the Monte Carlo (MC) coordinate system used in GEANT4 for dose calculations in spot ...