放射治疗中真空垫摆位的技术改进

目的：提高放射治疗中真空垫摆位的精度。方法将200例使用真空垫进行摆位的患者随机分为两组，传统组（100例）使用传统方法进行摆位，改进组（100例）使用改进过的方法进行摆位，用锥形束CT（CBCT）系统分析两组首次摆位时的误差；将传统组再随机分为两组，一组（50例）定时对真空垫抽真空，另一组（50例）“适时”对真空垫抽真空，用CBCT系统分析两组第15次摆位时的误差。结果与传统组相比，改进组在X、Y、Z轴方向上的摆位误差均有明显改善（P＜0.05）；与“适时”抽气组相比，定时抽气组在X、Z轴方向摆位误差有明显改善（P＜0.05）。结论真空垫摆位的技术改进有效提高了摆位精度。

Technical Improvement of Radiotherapy Positioning with Vacuum Cushion

Objective To improve the accuracy of radiotherapy positioning with vacuum cushion. Methods 200 patients who would undergo radiotherapy positioning with vacuum cushion were randomly divided into traditional group （100 cases） and improvement group （100 cases）. The radiotherapy positioning of traditional group was conducted by using traditional method and that of improvement group was conducted by using improved method. The errors of the ifrst positioning of the two groups were analyzed through CBCT system. Patients in traditional group were randomly divided into timing exhaust group （50 cases） and timely exhaust group （50 cases）. The vacuum pumping of timing exhaust group was conducted regularly and that of timely exhaust group was conducted in time. The errors of the 15th positioning of the two groups were analyzed through CBCT system. Results The positioning errors in X axis, Y axis and Z axis of improvement group were signiifcantly lower than those of traditional group （P〈0.05）. The positioning errors in X axis and Z axis of timing exhaust group were signiifcantly lower than those of timely exhaust group （P〈0.05）. Conclusion Technical improvement of radiotherapy positioning with vacuum cushion has improved the radiotherapy positioning accuracy.