探讨MatriXX在验证调强放射治疗计划中的应用

Application of MatriXX System for Intensity-modulated Radiotherapy Planning

目的:通过二维电离室矩阵MatriXX对调强放射治疗计划进行二维剂量分布验证,根据验证结果来探讨其在调强放射治疗计划剂量验证中的应用。方法:利用德国IBA公司的MatriXX二维电离室矩阵及SP34等效固体水模对加速器执行的128例患者的调强放射治疗计划实施测量,获取特定层面二维剂量分布。利用OmniPro I’mRT软件,把患者计划植入模体后计划系统计算的剂量与MatriXX实测得到输出剂量进行比对,然后进行Gamma分析。结果:实际测量的相对剂量分布与计划系统模体中计算的相对剂量分布采用Gamma法(3 mm/3%)和(4 mm/4%)进行分析,以γ值小于1的百分比>95%作为要求,所有计划γ<1的百分比>95%的通过率为100%。结论:MatriXX在验证调强放射治疗计划中具有省时省力、快速简便等优势,是目前剂量验证的较为准确的QA工具之一。

Objective To research the dominance of the plan in the intensity-modulated radiotherapy verification by using a 2-D air vented ionization chamber array MatriXX in verifying the 2-D Planar dose of intensity-modulated radiotherapy plans. Methods A 2-D air vented ionization chamber array, MatriXX and Scandinix SP34 equivalent solid water phantom from IBA company were used to verify the dose distribution of 128 intensity-modulated radiotherapy planning, and to obtain 2-D planar dose curves, and a OmniPro I＇mRT software was used to analyze using Gamma criteria, either in the planar dose distribution of MatriXX observed or in the planar dose distribution of intensity-modulated radiotherapy system planning calculated. Results Analyzing the relative dose distribution observed versus planning system calculated by the 3 mm/3% and 4 mm4% Gamma criteria with ratios〉95% of T parameter〈l, all plans of percent was 100%. Conclusion MatriXX, with advantages of time and labor saving, fast and simple in intensity-modulated radiotherapy plans, thus, is one of the tools for QA in the dose verification of accuracy.