宫颈癌在图像引导调强放疗中摆位误差的分析

目的 分析宫颈癌在图像引导调强放疗中的摆位误差.方法 选取2010年1月～2014年1月30例宫颈癌患者为研究对象,均经病理活检确诊,未进行过放化疗.对30例宫颈癌患者行IGRT治疗,观察首次摆位后X轴（左右）、Y轴（腹背）、Z轴（头脚）方向偏移误差,计算出摆位误差值下靶区和危及器官股骨头、膀胱、直肠的剂量分布范围.结果 30例宫颈癌患者共行150次首次摆位后CBCT扫描,在X、Y、Z轴向上的误差值分别为0.639±3.06、0.785±2.59、0.712±2.25;靶区及危及股骨头、膀胱、直肠的剂量变化范围分别为-7.01～8.62、-12.6～43.80、-10.34～11.97.结论 宫颈癌在图像引导调强放疗中存在摆位误差,且宫颈癌的摆位误差可引起靶区和危及器官剂量明显变化,因此,分析摆位误差产生原因及误差范围,才能有效提高放疗的准确性.

The analysis of bit errors for patients sith cervicaf cancer by IGRT

Objective To analyze setup error for patientos with cervical cancer in image-guided intensity modulated radiotherapy. Methods From January 2010 to January 2014,30 cases of cervical cancer patients for the study, were confirmed by biopsy , had not been chemotherapy. 30 cases of cervical cancer line IGRT treatment was observed for the first time after positioning the X-axis（left and right）, Y-axis（front）, Z-axis（head and feet） orientation offset error, calculated under the positioning error value targets and organs at risk the femoral head,bladder,rectum dose distribution. Results The 30 cases of cervical cancer line 150 times after initial placement CBCT scan was 0.639±3.06 0.785±2.59,0.712±2.25 respectively, in X, Y, Z axis on the error value; targets and femoral threatening, bladder, rectal dosage range of-7.01-8.62, -12.6-43.80, -10.34-11.97 respectively. Conclusion The presence of cervical setup errors, setup errors and cervical cancer can cause target organ doses and jeopardize significant change, therefore, analyze the causes of setup errors and error, in order to effectively improve the image--guided intensity modulated radiotherapy radiotherapy accuracy.