Saminathan Sathiyan, Manickam Ravikumar, Chandraraj Varatharaj
Department of Radiation Physics, Kidwai Memorial Institute of Oncology, Bangalore, 560029, India.
Australas Phys Eng Sci Med. 2011 Apr;34(1):55-61. doi: 10.1007/s13246-011-0058-4. Epub 2011 Feb 18.
In order to verify intensity modulated radiotherapy quality assurance procedure and to establish the practical base line commissioning, American Association of Physicists in Medicine-Task Group 119 test suite DICOM-RT images and structure were downloaded for planning and dosimetric comparison. The square slab phantom of water equivalent plastic was used for the measurement. This phantom can permit point dose measurement with ionization chamber by placing the chamber at 7.5 cm depth in the slab phantom. The planar dose measurements were carried out by positioning the Matrixx detector at 10 cm depth. The planning and measurements were performed as per AAPM TG119 guidelines. The test suite includes AP:PA field, band test, multitarget, prostate, head and neck and C-shape. The ion chamber measurements were within 3% of the planned dose for target and avoidance structure region. The ion chamber measurement results are in good agreement with the TG119 recommendation of ±3% for all the test suites. The planar dose measurements were performed with Matrixx for individual fields at the planned gantry angle. The results show that the pass criteria for γ ≤ 1 were between 93 to 97% for all the test cases. Our results are in good agreement with the TG119 recommendation. The present study aimed to compare the measured dose with the planned dose using computer planning system. The test suites were used to assess the planning and delivery systems so as to provide the basis for IMRT commissioning and QA.
为了验证调强放射治疗质量保证程序并建立实际的基线调试，下载了美国医学物理学家协会任务组119测试套件的DICOM-RT图像和结构用于计划和剂量学比较。使用水等效塑料的方形平板模体进行测量。通过将电离室放置在平板模体7.5厘米深处，该模体可以进行点剂量测量。通过将Matrixx探测器定位在10厘米深处进行平面剂量测量。计划和测量按照AAPM TG119指南进行。测试套件包括前后野、射野宽度测试、多靶区、前列腺、头颈部和C形。电离室测量结果在靶区和避让结构区域与计划剂量相差3%以内。所有测试套件的电离室测量结果与TG119推荐的±3%高度吻合。在计划的机架角度下，使用Matrixx对各个射野进行平面剂量测量。结果表明，所有测试病例中γ≤1的通过标准在93%至97%之间。我们的结果与TG119推荐高度吻合。本研究旨在使用计算机计划系统比较测量剂量和计划剂量。测试套件用于评估计划和交付系统，以便为调强放射治疗的调试和质量保证提供依据。
