EPID在盆腔肿瘤放疗中的摆位误差分析

目的探讨电子射野影像系统在盆腔肿瘤放疗中的摆位误差,以供临床参考。方法对17例盆腔肿瘤接受放疗的患者给予摆位误差的量化测定。所有病例给予CT的定位和放疗。将治疗过程中的电子射野影像系统所拍摄的正位和侧位片,与数字化重建图像的验证片进行对比分析,计算误差。结果 17例患者在每日摆位误差中,主要为前后的误差,在2mm～22mm之间,平均为(13.21±7.17)mm;其次为头脚,在1mm～23mm之间,平均为(8.01±5.32)mm;左右误差发生最小,在0.2mm～8.7mm之间,平均(5.27±3.99)mm。结论使用电子射野影像系统能够有效地对盆腔肿瘤放疗期间的摆位误差进行测定,为放疗提供初步的参考依据。

Objective Of electronic portal imaging system in pelvic radiotherapy in cancer of the pendulum position error for clinical reference. Methods Our hospital 17 cases of pelvic tumors were treated with radiotherapy quantify positioning errors. Given to the positioning of all cases CT and radiotherapy. The treatment of electronic portal imaging system to capture the anteroposterior and lateral films, and digital image reconstruction verification films were analyzed to calculate the error. Results 17 patients in the daily positioning errors, mainly before and after the error, in the 2mm - 22mm, the average of （13.21 ± 7.17） mm; followed by the head and feet, in 1mm- 23mm with an average of （8.01 ±5.32） mm; about the smallest error occurred in the 0.2mm - 8.7mm, the average （5.27 ± 3.99） mm. Conclusion The use of electronic portal imaging system can effectively during radiotherapy of pelvic tumors were measured positioning errors for the radiation to provide a preliminary reference.