Commissioning and validation of COMPASS system for VMAT patient specific quality assurance

13th South-East Asian Congress of Medical Physics 2015

物理学;医药卫生

Pimthong, J.^1 ; Kakanaporn, C.^2 ; Tuntipumiamorn, L.^2 ; Laojunun, P.^2 ; Iampongpaiboon, P.^2

Medical Physics School, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand^1

Division of Radiation Oncology, Department of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand^2

关键词: Advanced treatment;    Clinical application;    Dose verification;    Dose-volume histograms;    Ionization detectors;    Nasopharyngeal cancer;    Patient specific;    Volumetric modulated arc therapy;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/694/1/012025/pdf
DOI  :  10.1088/1742-6596/694/1/012025

学科分类：卫生学

来源: IOP

【 摘 要 】

Pre-treatment patient specific quality assurance (QA) of advanced treatment techniques such as volumetric modulated arc therapy (VMAT) is one of important QA in radiotherapy. The fast and reliable dosimetric device is required. The objective of this study is to commission and validate the performance of COMPASS system for dose verification of VMAT technique. The COMPASS system is composed of an array of ionization detectors (MatriXX) mounted to the gantry using a custom holder and software for the analysis and visualization of QA results. We validated the COMPASS software for basic and advanced clinical application. For the basic clinical study, the simple open field in various field sizes were validated in homogeneous phantom. And the advanced clinical application, the fifteen prostate and fifteen nasopharyngeal cancers VMAT plans were chosen to study. The treatment plans were measured by the MatriXX. The doses and dose-volume histograms (DVHs) reconstructed from the fluence measurements were compared to the TPS calculated plans. And also, the doses and DVHs computed using collapsed cone convolution (CCC) Algorithm were compared with Eclipse TPS calculated plans using Analytical Anisotropic Algorithm (AAA) that according to dose specified in ICRU 83 for PTV.