Objective To find and solve the setup problem by comparing of setup error between conventional radiotherapy and three-dimensional conformal radiatherapy for nasopharyngeal carcinoma ( NPC ).Methods 40 patients with NPC were assigned to receive conventional radiotherapy ( 20 patients ) or 3D conformal radiatherapy ( 20 patients ).The setup errors of the two therapies were analyzed.Results One hundred and twenty films were obtained from all the 40 patients.The setup errors of conventional radiotherapy were significantly larger than those of 3D conformal radiatherapy in X,Y,and Z axis direction (3.95 ± 2.10mm,3.50 ± 2.03 mm,and3.02 ± 2.10mmvs.1.78 ± 1.03 mm, 1.53 ± 0.92mm, and 1.60 ± 1.11 mm ).Gonclusions Setup errors can be reduced by strict quality control and application of 3D conformal radiatherapy.%目的 通过鼻咽癌常规放疗与适形放疗摆位误差的比较,找出摆位时存在的问题,并找出解决方法.方法 以进行放射治疗的40例鼻咽癌患者为对象,20例患者接受常规外照射,另外20例行适形放疗,对其摆位误差进行分析.结果 40例患者共拍摄120张射野验证片.常规放疗组摆位误差X轴(3.95±2.10) mm、Y轴(3.50±2.03) mm和Z轴(3.02±2.10) mm大于适形放疗组的X轴(1.78±1.03) mm、Y轴(1.53±0.92) mm和Z轴(1.60±1.11) mm.结论 通过严格的质量控制和采用适形放疗可以减少摆位误差,有效地提高摆位的重复性.
展开▼
