Patient-specific quality assurance for spot scanning proton beams using a large-volume liquid scintillator detector

[摘要] A large-volume liquid scintillator detector was used to measure individual energy layers from a clinical prostate treatment plan on a scanning proton beam system. Lateral and beam's-eye view images of the dose distribution were acquired with two CCD cameras facing adjacent sides of a scintillator tank. The measured dose images were compared with calculated dose distributions from a validated Monte Carlo model. The measured and calculated dose distributions showed good agreement, with the exception of the Bragg peak region of the lateral view, which exhibited ionization quenching. The beam's-eye and lateral views achieved gamma analysis passing rates of 99.7% and 92.5%, respectively, using gamma criteria of 3%, 3 mm. Large-volume scintillator detectors show promise for quick and accurate measurements of patient treatment fields for scanning proton beam systems.

[发布机构] Department of Radiation Physics, University of Texas, MD Anderson Cancer Center, Houston; TX; 77030, United States^1

[关键词] Accurate measurement;Dose distributions;Ionization quenching;Liquid scintillator detectors;Monte Carlo model;Patient specific;Prostate treatment;Scintillator detector