模拟定位机影像工作站在三维适形放射治疗计划射野位置验证中的应用

摘要

Objective To explore the effectiveness of application of the radiotherapy simulator image workstation in position veriifcation of irradiation ifelds in the 3D-CRT (Three Dimensional Conformal Radiotherapy) plans. Methods Comparisons between verification field images generated by the radiotherapy simulator and DRR (Digitally Reconstructed Radiograph) images generated by the treatment planning system were made in the image workstation to measure the image setup errors. Results Position veriifcation of the irradiation ifelds of 254 tumor patients’ radiotherapy plan was conducted through the radiotherapy simulator. After position verification, the setup errors of head and neck cancer patients’ radiotherapy plans in the axis of x, y and z were (-1.0±1.0) mm, (-1±2) mm and (2±1) mm respectively;while for patients with chest and abdominal cancers, the setup errors were (1±2) mm, (0±2) mm and (3±1) mm;for pelvic cancer patients, the setup errors were (1±1) mm, (1±2) mm and (2±2) mm. After position veriifcation, the setup errors of all the patients’ 3D-CRT plans were controlled within the permissible range. Conclusion Radiotherapy simulator image workstation can verify the irradiation ifelds of 3D-CRT plans to reduce the setup errors.%目的：探讨模拟定位机的影像工作站在三维适形放射治疗（3D-CRT）计划射野位置验证中的应用价值。方法在影像工作站上比较模拟定位机的验证野影像和治疗计划系统的验证野数字重建影像（DRR），测量摆位误差。结果254例患者的放疗计划通过模拟定位机进行了射野的位置验证。位置校正后，头颈部肿瘤患者的放疗计划在x轴、y轴、z轴方向上的误差分别为（-1.0±1.0）mm，（-1±2）mm，（2±1）mm；胸腹部肿瘤患者为（1±2）mm，（0±2）mm，（3±1）mm；盆腔肿瘤患者为（1±1）mm，（1±2）mm，（2±2）mm。位置校正后，各放疗计划的误差都能够控制在允许范围内。结论模拟定位机的影像工作站可以对放疗计划进行射野位置验证，减少摆位误差。