Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Reduction of prostate intrafraction motion using gas-release rectal balloons

Journal Article · · Medical Physics
DOI:https://doi.org/10.1118/1.4749932· OSTI ID:22099025
; ; ; ; ; ; ; ;  [1]
  1. Department of Radiation Oncology, University of Florida Proton Therapy Institute, Jacksonville, Florida 32206 (United States)
Purpose: To analyze prostate intrafraction motion using both non-gas-release (NGR) and gas-release (GR) rectal balloons and to evaluate the ability of GR rectal balloons to reduce prostate intrafraction motion. Methods: Twenty-nine patients with NGR rectal balloons and 29 patients with GR balloons were randomly selected from prostate patients treated with proton therapy at University of Florida Proton Therapy Institute (Jacksonville, FL). Their pretreatment and post-treatment orthogonal radiographs were analyzed, and both pretreatment setup residual error and intrafraction-motion data were obtained. Population histograms of intrafraction motion were plotted for both types of balloons. Population planning target-volume (PTV) margins were calculated with the van Herk formula of 2.5{Sigma}+ 0.7{sigma} to account for setup residual errors and intrafraction motion errors. Results: Pretreatment and post-treatment radiographs indicated that the use of gas-release rectal balloons reduced prostate intrafraction motion along superior-inferior (SI) and anterior-posterior (AP) directions. Similar patient setup residual errors were exhibited for both types of balloons. Gas-release rectal balloons resulted in PTV margin reductions from 3.9 to 2.8 mm in the SI direction, 3.1 to 1.8 mm in the AP direction, and an increase from 1.9 to 2.1 mm in the left-right direction. Conclusions: Prostate intrafraction motion is an important uncertainty source in radiotherapy after image-guided patient setup with online corrections. Compared to non-gas-release rectal balloons, gas-release balloons can reduce prostate intrafraction motion in the SI and AP directions caused by gas buildup.
OSTI ID:
22099025
Journal Information:
Medical Physics, Journal Name: Medical Physics Journal Issue: 10 Vol. 39; ISSN 0094-2405; ISSN MPHYA6
Country of Publication:
United States
Language:
English

Similar Records

Analysis of Prostate Patient Setup and Tracking Data: Potential Intervention Strategies
Journal Article · Tue Nov 01 00:00:00 EDT 2011 · International Journal of Radiation Oncology, Biology and Physics · OSTI ID:21590471

Prostate and Patient Intrafraction Motion: Impact on Treatment Time-Dependent Planning Margins for Patients With Endorectal Balloon
Journal Article · Mon Jul 15 00:00:00 EDT 2013 · International Journal of Radiation Oncology, Biology and Physics · OSTI ID:22224538

SU-E-J-103: Setup Errors Analysis by Cone-Beam CT (CBCT)-Based Imaged-Guided Intensity Modulated Radiotherapy for Esophageal Cancer
Journal Article · Sun Jun 01 00:00:00 EDT 2014 · Medical Physics · OSTI ID:22325257