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Results for "average shift": 39 found

60RPM Rotational Winston Lutz Test to Characterize Operational MV-Kv Offset on Reflexion X1 System

Authors: Huixiao Chen, Ethan Hartowicz, Lichung Ku, Tim Perez, Ray Yang

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

Abstract Preview: Purpose: To characterize MV-kV isocenter offset on a novel ring gantry radiotherapy system where the Linac, PET, kV-CT, and MV imaging subsystems rotate together at native operating speed of 60RPM.

A Comparative Analysis of the Dosimetric, Alignment, and Setup Efficiency in Left Breast Cancer Radiotherapy Treated with Dibh Using ABC and Sgrt

Authors: Aaron Conard, Victoria Croog, Marie Gurka, Lan Lin

Affiliation: Johns Hopkins University

Abstract Preview: Purpose:
This study evaluates the utility of the Active Breathing Coordinator (ABC) and Surface Guided Radiation Therapy (SGRT) techniques in implementing Deep Inspiration Breath Hold (DIBH) for le...

A Comparison of on-Isocenter Vs Off-Isocenter Planning for Lung SBRT on the Viewray Mridian

Authors: Nebi Demez, Shyam Pokharel, Suresh Rana, Lauren A. Rigsby, Tino Romaguera, Nishan Shrestha

Affiliation: Lynn Cancer Institute, Boca Raton Regional Hospital, Baptist Health South Florida

Abstract Preview: Purpose: Treatment plans on the ViewRay MRIdian are often planned with the target placed off isocenter due to the proximity of the bore to the patient, allowing for limited shifts. This is especially ...

A Framework for the Standardization of Radiomics Classes in the Presence of Blur and Noise

Authors: Huay Din, Grace Jianan Gang, Grace Hyun Kim, Michael F. McNitt-Gray, Joseph W. Stayman, Yijie Yuan

Affiliation: Johns Hopkins University, John Hopkins University, University of Pennsylvania, David Geffen School of Medicine at UCLA

Abstract Preview: Purpose:
Radiomics rely on quantitative features to discern underlying biological signatures. However, feature dependence on the imaging systems themselves hampers the creation of reproducible and ...

A Patient-Specific Approach to Surface Guided-DIBH SBRT Candidacy Using Surface Deformation Maps

Authors: Savannah Decker, Grace Gwe-Ya Kim, Laura Padilla

Affiliation: UC San Diego, University of California San Diego

Abstract Preview: Purpose: The success of surface-guided deep-inspiration breath-hold (SG-DIBH) treatments depends on accurate identification of suitable candidates. Sub-optimal patient selection can result in prolonge...

A Real-Time Framework for Fiducial Tracking and Intrafraction Motion Assessment of Cyberknife in Stereotactic Body Radiation Therapy for Liver Cancer

Authors: Ruiyan Du, Mingzhu Li, Ying Li, Wei Liu, Shihuan Qin, Yiming Ren, Biao Tu, Hui Xu, Lian Zhang, Xiao Zhang, Zengren Zhao

Affiliation: Department of General Surgery, Hebei Key Laboratory of Colorectal Cancer Precision Diagnosis and Treatment, The First Hospital of Hebei Medical University, Medical AI Lab, The First Hospital of Hebei Medical University, Hebei Provincial Engineering Research Center for AI-Based Cancer Treatment Decision-Making, The First Hospital of Hebei Medical University, Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Department of Radiation Oncology, Mayo Clinic, Department of Oncology, The First Hospital of Hebei Medical University

Abstract Preview: Purpose: Fiducial tracking is widely used in CyberKnife to dynamically guide the gantry for moving target like liver cancer stereotactic body radiation therapy (SBRT). This study developed a robust fr...

Adversarial Diffusion-Based Self-Supervised Learning for High-Resolution MR Imaging

Authors: Zachary Buchwald, Chih-Wei Chang, Zach Eidex, Richard L.J. Qiu, Mojtaba Safari, Shansong Wang, Xiaofeng Yang, David Yu

Affiliation: Emory University and Winship Cancer Institute, Emory University, Department of Radiation Oncology and Winship Cancer Institute, Emory University

Abstract Preview: Purpose: MRI offers excellent soft tissue contrast for diagnosis and treatment but suffers from long acquisition times, causing patient discomfort and motion artifacts. To accelerate MRI, supervised d...

An Agglomerative Clustering-Based Program for Optimizing Multiple-Target SRS Treatment Planning

Authors: Josephine Chen, CheukKai Becket Hui, Yildirim D. Mutaf

Affiliation: Kaiser Permanente

Abstract Preview: Purpose:
To demonstrate the effectiveness of a target clustering program in generating cluster configurations and isocenter placements for multiple brain lesions in SRS treatment planning, with the...

Brain Structural Covariance Networks in Nicotine-Dependent Users: A Graph Analysis

Authors: Humberto Monsivais, Brian A. Taylor, Francesco Versace

Affiliation: Purdue University, Department of Behavioral Science, Division of Cancer Prevention and Population Sciences, The University of Texas MD Anderson Cancer Center, Department of Imaging Physics, The University of Texas MD Anderson Cancer Center

Abstract Preview: Purpose: To identify possible signatures of altered brain morphometry in nicotine-dependency via a structural covariance network approach.

Methods: Fifty-one healthy controls (HC:27M, mean age=...

CBCT and Exactrac Dynamic Agreement for Patient Positioning during Spine SRS/SBRT Treatments

Authors: Martha J. Malin, Matthew Schelin

Affiliation: NYU Langone Health

Abstract Preview: Purpose: To evaluate the agreement between ExacTrac Dynamic (ETD) and CBCT-based positioning for spine SRS/SBRT treatments during initial patient setup and repositioning after intrafraction motion.

Can We Use Smaller Margin for the Planned Target Volume with Adaptive Radiotherapy?

Authors: Mahmoud H Abdelgawad, Shahabeddin mostafanazhad Aslmarand, Lili Chen, Xiaoming Chen, Ahmed A. Eldib, Teh Lin, Chang Ming Charlie Ma, Robert A. Price

Affiliation: Physics department, Faculty of science, Al-Azhar University, Fox Chase Cancer Center

Abstract Preview: Purpose: Many modern radiotherapy clinics are moving to online adaptive radiotherapy. A recent upgrade of the CBCT-based adaptive radiotherapy system introduced ultra-high-speed image acquisition. Thi...

Comparison Study of Shift Frequency and Magnitude By Prostate Fiducial Tracking System: Triggered Image and Calypso

Authors: David J. Carlson, Yiu-Hsin Chang, Zhe (Jay) Chen, Hyosung Cho, Dae Yup Han, MinYoung Lee, Weili Zhong

Affiliation: Department of Therapeutic Radiology, Yale University School of Medicine, Yonsei University

Abstract Preview: Purpose:
To compare the intra-fractional motion tracking sensitivity of prostate fiducial markers using triggered imaging and calypso tracking for prostate cancer cases.
Methods:
This study w...

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...

Confidence in a Tattoo-Less Transition

Authors: Laura A. Doyle, Amy S. Harrison, Allyson P Koecher, Jackson D Reeves, Lindsay B Romak

Affiliation: Christiana Care

Abstract Preview: Purpose: Surface guided radiation therapy (SGRT) is increasingly utilized in radiation oncology, allowing for transition away from permanent skin marks to SGRT-based daily treatment setup. Following i...

Design of Filtimator (Filter + Collimator) for CBCT of Pediatric Cancer Patients Receiving Proton Therapy

Authors: Soon N. Huh, Perry B. Johnson, Jiyeon Park, Ryan Stevens

Affiliation: University of Florida Health Proton Therapy Institute, UF Health Proton Therapy Institute, UFHPTI

Abstract Preview: Purpose:
Cone-beam computed tomography (CBCT) doses shall be limited for pediatric patients in clinical settings. Device called Filtimator (filter+collimator) was custom designed to reduce setup CB...

Dosimetric Comparative Analysis of Modulated and Non Modulated Electron Bolus in Nasal Electron Therapy

Authors: Stephen D. Davis, Alonso N. Gutierrez, Noah S. Kalman, Michael Leyva, Alejandro Rene Llanes Lopez, William Romaguera, Ranjini P. Tolakanahalli, Deborah Wang

Affiliation: Miami Cancer Institute, Baptist Health South Florida, Miami Cancer Institute, Miami Cancer Institute, Baptist Health

Abstract Preview: Purpose: To evaluate whether a modulated electron bolus (MEB) technique improves both nominal and shifted dose distributions in nasal electron therapy as compared to a non‑modulated, uniform‑thickness...

Dosimetry Comparison of Surface-Guided and Orthogonal X-Ray Film-Based Setups for Proton Pencil-Beam Scanning in Breast Cancer Treatment

Authors: Darren Kaplan, Chenguang Liu, Mark Pankuch

Affiliation: Northwestern Medicine Proton Center

Abstract Preview: Purpose: This study evaluates the hypothesis that surface-guided radiation therapy for the breast or chest wall using proton PBS provides comparable target coverage and OARs sparing to x-ray-based IGR...

Estimation of Brain Tumor’s Intra-Fraction Movement during Radiosurgery Using Fiducial Markers on the Skin Surface – a Simulation Study

Authors: Damien C. Mathew, Brandon Hai Nguyen, Satwik Pani, Yoichi Watanabe

Affiliation: Minnespolis Radiation Oncology, Department of Radiation Oncology, University of Minnesota Medical School, Washington University

Abstract Preview: Purpose: To formulate a computational algorithm to quantify the tumor movement from the motion data of landmarks on the brain surface. To estimate the magnitude of tumor movement when the head makes a...

Evaluating Dose Variability in Bladder Contouring for MR-Guided Prostate Cancer Radiotherapy

Authors: Emily Helen Hayes, Chihray Liu

Affiliation: University of Florida

Abstract Preview: Purpose: To evaluate dosimetric discrepancies in bladder dose calculations among rigid, deformed, and manual contouring methods in prostate cancer patients and assess dose variations resulting from bl...

Evaluation of Potential Dosimetric Risks from Intra-Fractional Motion in Single-Isocenter Stereotactic Radiosurgery

Authors: Brian D. Casto, Mathew Y Kang, Lichung Ku, Samuel J Wang, Joseph B. Ying, Walker Ray Zimmerman

Affiliation: Salem Health Cancer Center, Salem Health

Abstract Preview: Purpose: Varian HyperArc is an advanced radiotherapy module designed to efficiently deliver high-quality multi-target stereotactic radiosurgery (SRS) treatment plans on Varian linacs. However, the int...

Evaluation of the Dosimetric Characteristics of Multi-Layers of Brass Mesh Bolus for Electron Treatment

Authors: Yunzhi Ma, Ling Zhuang

Affiliation: Northwestern Medicine

Abstract Preview: Purpose: Multiple layers of brass mesh bolus (RPD, Inc., Albertville, MN) may be needed to provide better body conformity and sufficient dose build up on patient surface during electron treatment. Thi...

Four-Dimensional Computed Tomography Based on 16cm-Long Detectors Vs 4cm-Long Detectors: Dose Validation

Authors: Qianyi Xu, Inhwan Yeo

Affiliation: INOVA Schar Cancer Institute, Thomas Jefferson University

Abstract Preview: Purpose:
Four-dimensional computed tomography(4DCT) is prone to a geometrical error when respiration changes upon patient shift. 4DCT with a longer-length detector(16cm), uninvolving the shift, has...

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...

Imaging of Mn Washout in the Individual Welder Brain after Wearing Powered Air-Purifying Respirators (PAPRs)

Authors: Ulrike Dydak, Chia-Tien Hsu, Chang Geun Lee, Cora Mizimakoski, Humberto Monsivais, Jae Hong Park

Affiliation: Purdue University

Abstract Preview: Purpose: Overexposure to manganese (Mn) from inhaling welding fumes can lead to cognitive and motor deficits. We developed a whole-brain Mn-mapping approach to detect subtle but significant increases ...

Improved SNR and Estimation Accuracy for Deuterium-MRI Acquired with Chemical Shift Imaging at 7 Tesla

Authors: Muhammed AR Anjum, Andrew J. Fagan

Affiliation: Mayo Clinic

Abstract Preview: Purpose:
This study describes a novel post-processing method to boost image SNR for deuterium-MRI acquired using chemical shift imaging (CSI) at 7T. Deuterium MRI via exogenous administration of a ...

Improved Setup Accuracy for Dibh Whole Breast Radiotherapy with Surface-Guided Radiation Therapy

Authors: CheukKai Becket Hui, Goldie M. Klein, Yildirim D. Mutaf, Amir Pourmoghaddas

Affiliation: UC Health, Kaiser Permanente

Abstract Preview: Purpose:
In this study, we investigated the effect of SGRT (Align-RT) implementation on patient setup accuracy for DIBH breast radiotherapy treatments.
Methods:
We extracted vertical post-ima...

Margins to Account for Cardiac and Respiratory Motion in Cardiac Radioablation

Authors: Alanah M. Bergman, Marc W Deyell, Tania Karan, Jakob Marshall, Justin Poon, Devin Schellenberg, Steven Thomas, Richard Thompson

Affiliation: University of British Columbia, University of Alberta, BC Cancer

Abstract Preview: Purpose: A conservative approach to account for random errors due to intra-fraction cardiac and respiratory motion during cardiac radioablation (CR) is to define a margin equal to the amplitude of car...

Mask-Less Adaptable Headrest for Head-and-Neck Radiotherapy

Authors: Alyssa Capizzi, John J Dombrowski, Nabil N. Khater

Affiliation: Saint Louis University

Abstract Preview: Purpose: To evaluate a mask-less adaptable headrest (MAHR) prototype for head-and-neck IMRT designed to reduce random and systematic shifts of patients’ setups. MAHR complements current image-guidance...

Multi-Criteria Optimization in Medical Physics Resource Allocation: Design of an Efficient and Equitable Scheduling System

Authors: Dalton Griner, Kathryn L. Kolsky, Joseph John Lucido, Andrew J. Veres

Affiliation: Mayo Clinic

Abstract Preview: Purpose: This project aimed to automate a complex and time-consuming employee scheduling process. By replacing the traditional manual method with a multi-criteria optimization-based system (MCO), the ...

Needle-in-Needle Technique: A Lifeline for HDR Syed Interstitial Implants with Unusable Catheters

Authors: Jochen Cammin, Yushi Chang, Mariana Guerrero, Kai Jiang, Narottam Lamichhane, Elizabeth Nichols

Affiliation: Department of Radiation Oncology, UT Southwestern Medical Center, University of Maryland School of Medicine, Department of Radiation Oncology, University of Maryland School of Medicine

Abstract Preview: Purpose: Our institution handles a large GYN SYED patient load (5 HDR fractions over 3 days). In recent years, we faced many logistical challenges, such as broken/contaminated catheters, which disrupt...

Optimizing PTV Coverage in VMAT Breast Plans: A Robust Evaluation of Motion and Flash Margins

Authors: William N. Duggar, John C. White

Affiliation: UMMC, University of Mississippi Medical Center

Abstract Preview: Purpose:
To evaluate the impact of patient motion on PTV coverage for 95% and 90% target volumes in VMAT breast treatment plans and to determine the appropriate flash margins required to maintain r...

Patient-Specific Bio-Morphological Features in Cherenkov Imaging for Positioning Verification: A Retrospective Analysis in Accelerated Partial Breast Irradiation (aPBI) VMAT Radiotherapy

Authors: Yao Chen, Lesley A Jarvis, Allison Matous, Rongxiao Zhang

Affiliation: Dartmouth College, University of Missouri, Dartmouth Cancer Center, Dartmouth Health

Abstract Preview: Purpose: Precise patient positioning is critical in accelerated partial breast irradiation (aPBI) to ensure accurate dose delivery to the tumor bed while minimizing exposure to surrounding healthy tis...

Portable Label-Free Raman Spectroscopy for Complementary Evaluation of Radiation Induced Tissue Damage

Authors: Marwan Belal AbuHaija, Anis Ahmad, Chase Prescott Anderson, Nesrin Dogan, John C. Ford, Alan Pollack, Junwei Shi, Jorge D Vega, Gabriel Enrique de Hostos

Affiliation: University of Miami, University of Miami Sylvester Comprehensive Cancer Center

Abstract Preview: Purpose: Raman Spectroscopy (RS) is a non-invasive, label free imaging modality that gathers intrinsic molecular vibrational information. Portable RS systems expand affordability and convenience, supp...

Positional Accuracy and Clinical Recommendations for HDR Brachytherapy Ring Applicators: A Commissioning and Evaluation Study

Authors: Peter G. Maxim, Michael P. Reilly, Mengying Shi, Maryam Shirmohammad, Darren M. Zuro

Affiliation: University of California Irvine

Abstract Preview: Purpose: This study aims to assess the positional accuracy of HDR brachytherapy ring applicators, quantify the extent of positional deviation, and provide clinical recommendations for GYN HDR brachyth...

Prostate SBRT Motion Study and PTV Margin Evaluation with Exactrac Fiducial Tracking

Authors: Ahmad K. Al-Basheer, Andrew Clarke Grice, Kelly E. Hosier, Mark Logsdon, Evan A. Silverstein, Chris Tunnicliff, Chuan Wu

Affiliation: Sutter Medical Foundation, Sutter Health

Abstract Preview: Purpose: For Prostate SBRT Boost treatments, determine whether a uniform 2mm CTV to PTV margin is sufficient to give 95% dose coverage to the CTV in 90% of patients via a modified Van Herk Margin Form...

Robust Evaluation of the Pronumbra Immobilization System for Proton Therapy HN Treatment

Authors: Laura Buchanan, Samantha G. Hedrick, Stephen L. Mahan, Isabella Pfeiffer, Chester R. Ramsey

Affiliation: Thompson Proton Center

Abstract Preview: Purpose: The CQ Medical kVue Pronumbra Head & Neck (HN) System is a new immobilization device for proton therapy. The mask includes 4 large knobs that attach to the board with built-in shims. These kn...

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...

Use of Radiopaque Rectal Spacer for IGRT – a Preliminary Analysis of Alignment Accuracy and Interobserver Variability

Authors: Joseph A. Miccio, Nicholas J. Potter, Zain Siddiqui

Affiliation: Penn State Health Milton S. Hershey Medical Center

Abstract Preview: Purpose: Fiducial markers are the gold standard for prostate alignment during CT-based image-guided radiotherapy (IGRT). Radiopaque hydrogel rectal spacers reduce rectal toxicity by displacing the rec...

Using Varian’s Obi Tools to Develop a CBCT Workflow with Triggered Imaging for Spine SBRT Intrafraction Motion Monitoring

Authors: Yi An, David J. Carlson, Zhe (Jay) Chen, Jun Deng, Dae Yup Han, Sameer Taneja

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

Abstract Preview: Purpose: Spine Stereotactic radiosurgery (SSR) delivers a large radiation dose and utilizes narrow PTV margins, on the order of 1 mm, to avoid excess dose to the spinal cord. Because of this, intrafra...