摘要
目的探讨逆向调强适形放疗(IMRT)的剂量学验证方法,保证接受治疗患者剂量的准确性。方法随机抽取30例鼻咽癌患者,进行CT定位扫描,然后把图像传输至核通PLATO三维逆向治疗计划系统,并设计出均分野(七野)治疗计划。利用固体水模板在治疗计划系统中建立三维等效模体,将待验证的IMRT计划套于模体内,分别计算出每野在模体中的剂量分布,选取模体中感兴趣平面上的每野剂量分布,传输至MAPCHECK验证软件系统,在加速器下进行二维剂量模拟照射并与计划系统计算的结果相比较,验证相对剂量和绝对剂量。结果采用DTA方法,剂量位置限定在3%/3mm标准条件下,所有射野中相对量的通过率在85%～100%之间,绝对量的平均通过率在80.7%～100%之间。结论剂量学验证是IMRT临床实施的可靠保证,使用MAPCHECK分析软件进行剂量验证具有适时、方便、快捷的特点,免去了胶片验证法中冲洗、扫描胶片的过程,也减少了大部分的系统误差。因此,MAPCHECK分析软件如今已成为我院剂量验证的常规工具。
Objective To explore the method of dose verification for patient treated with IMRT, make sure the accuracy of dose delived to patients. Methods Chose 30 patients randomly, and sent their CT images afer taking CT sanning to 3D inverse treatment planning system （PLATO V2.0 ,Nucltron）.Designed the IMRT plan using 7 splitte beams, and transplanted these plans to 3D equivalent phantom inside TPS.Obtained the dose distribution of every beam in the phantom.Sent the interested dose distribution lay to MAPCHECK,comparing it with the dose actually delivered under the LinCA, verify the difference for the relative and absolute dose.Results Using DTA method ,the average pass percent for relative dose was 85%～100% ,the absolute dose was 80.7%～100%.Conclusion Dose verification before treatment is obligatory and necessary, owing to the good characteristic of MAPCHECK： timing,convenient,fast,etc. MAPCHECK is the routine dosimetric verification tool for IMRT plan in our hosptial.
出处
《中国医疗设备》
2010年第2期16-18,共3页
China Medical Devices
