Dose verification of volumetric modulated arc therapy (VMAT) by use of in-treatment linac parameters
Dose verification of volumetric modulated arc therapy (VMAT) by use of in-treatment linac parameters
复制标题
使用治疗中直线加速器参数验证容积调制电弧疗法 (VMAT) 的剂量
DOI：
10.1007/s12194-013-0205-6
复制
发表时间：
2013
影响因子：
1.6
通讯作者：
Nakagawa K
中科院分区：
文献类型：
--
作者：
Haga A;Sakumi A;Okano Y;Itoh S;Saotome N;Kida S;Igaki H;Shiraishi K;Yamashita H;Ohtomo K;Nakagawa K
在前列腺癌、肺癌和头颈癌患者的体积调节电弧治疗的临床交付过程中，记录了多叶准直器（MLC）位置和颌骨位置、累积监测单位（MUs）和相应的龙门角度等直线参数。然后，将直线参数转换为治疗计划系统中使用的光束数据格式，重建剂量分布。将剂量-体积直方图和剂量差（DD）与治疗方案中相应值进行比较。当光束强度或MLC/颚速度发生突然变化时，观察到治疗中直线参数的可重复性误差。肺癌患者的最大累积MU误差大于4 MU，前列腺癌和头颈癌患者的最大MLC位置超过5 mm。然而，这些误差很快在下一个控制点得到补偿。在本研究中分析的所有治疗在计划目标量的准确度为0.4%。累积剂量在规定剂量的3%以内与计划剂量一致。前列腺癌、肺癌和头颈癌患者1%的DD分别为处方剂量的93.9%、99.9%和93.4%。
Linac parameters such as the multi-leaf collimator (MLC) position and jaw position, cumulative monitor units (MUs), and the corresponding gantry angle were recorded during the clinical delivery of volumetric modulated arc therapy for prostate, lung, and head/neck cancer patients. Then, linac parameters were converted into the beam-data format used in the treatment planning system, and the dose distribution was reconstructed. The dose-volume histogram and the dose difference (DD) were compared with the corresponding values in the treatment plan. A reproducible error of in-treatment linac parameters was observed when a sudden change of beam intensity or MLC/jaw speed occurred. The maximum cumulative MU error was more than 4 MU for lung cancer cases, and the maximum MLC position exceeded 5 mm for prostate and head/neck cancer patients. However, these errors were quickly compensated for at the next control point. All treatments analyzed in the present study were delivered within 0.4 % accuracy at the planning target volume. The cumulative dose agreed with that of the plan within 3 % of the prescribed dose. The 1 % DD was 93.9, 99.9, and 93.4 % of the prescription dose for prostate, lung, and head/neck cancer patients, respectively.