不同部位肿瘤螺旋断层放射治疗校正误差分析  

Analysis of the Corrected Error for Different Parts of the Tumor with Helical Tomotherapy

作　　者：周桂霞[1] 徐寿平[1] 杨艳[1] 杨东[1] 解传滨[1] 尹雷鸣[1] 

机构地区：[1]解放军总医院放射治疗科,北京市100853

出　　处：《中国肿瘤临床》2010年第10期587-589,共3页Chinese Journal of Clinical Oncology

摘　　要：目的:研究不同部位肿瘤在螺旋断层放射治疗前的校正误差。方法:选取74例不同部位肿瘤患者,其中头颈部肿瘤20例,胸部肿瘤17例,上腹部肿瘤22例,盆腔肿瘤15例。放疗前行MVCT扫描共1757次,扫描次数范围10～33次,平均每例扫描24次。结果:各部位肿瘤校正误差Z轴相对较小,<3mm误差范围在82.35%～95.99%之间。其次是X轴方向,<3mm误差范围是51.45%～74.67%。Y轴误差相对较大,误差<3mm除头颈部位是68.63%外,其它三个部位分别为41.8l%、42.47%和31.90%;而>5mm误差Y轴在盆腔部位高达47.96%;其次是腹部和胸部,分别为34.89%和30.69%,头颈部位最小,占10.64%。结论:螺旋断层放射治疗纠正了治疗误差,做到了真正意义上的精确放疗;Y轴治疗误差较大,提示制定治疗计划时特殊考虑PTV边界的外放;同时重视治疗中计划的更改和进一步提高技术员摆位的准确性。Objective： To investigate the impact of uncorrected setup errors of helical tomotherapy for the different parts of tumors. Methods： A total of 74 patients were treated with helical tomotherapy, among which there were 20 head and neck tumors, 17 thoracic tumors, 22 upper abdominal tumors and 15 pelvic tumors. All patients received MVCT scan prior to treatment delivery. A combined total of 1757 scans were analyzed. The range of the scanning fractions was between 10 and 33. The average value was 24. Results： For different parts of tumors, the corrected error rate for the Z-axis was the smallest, with a ratio for 〈3mm of 82.35%-95.99%. For the X-axis, the ratio for 〈3mm was 51.45%-74.67%. The error rate for the Y-axis was the largest, with a ratio for 〈3mm of 68.3% for head and neck tumor. The ratios of corrected error for the other parts were 41.81%, 42.47% and 31.90%, respectively. The ratio for the Y-axis for 〉5mm on pelvic tumors was 47.96%, and the others on thoracic and abdominal tumors were 34.89% and 30.69%. The ratio for 〉5mm on head and neck tumors was only 10.64%. Conclusion： With helical tomotherapy technique, the corrected error could be used as a guide to greatly improve the precision of the treatment area by allowing the technician to correctly design the planning target volume （PTV） and then modify the plan accordingly during treatment.

关 键 词：螺旋断层放疗 MVCT扫描 校正误差 

分 类 号：R730.5[医药卫生—肿瘤]