体位真空袋在胸部肿瘤放疗中的应用探讨

目的探讨体位真空袋在胸部肿瘤放疗中的应用。方法随机抽取实施胸部放疗的患者60例，分成A、B、C三组。每组20例，A组行常规固定技术放疗；B组行体位真空袋固定技术放疗；C组在真空袋固定技术基础上，在患者胸部两侧标记水平参考线。各组均拍摄正、侧位验证片，并每周拍摄验证片与初始验证片相比较。结果各组在X、Y、Z轴方向的摆位误差结果：A组X=（5．3±2．8）mm，Y=（3．8±2．3）mm，Z=（6．7±3．3）mm；B组X=（3．6±1．7）mm，Y=（3．2±1．8）mm，Z=（6．2±2．6）mm；C组Z=（3．1±1．6）mm。其中A和B组的X轴数据比较有统计学意义，Y、Z轴则无统计学意义；B和C组的Z轴比较有显著的统计学意义。结论胸部放疗中，应用体位真空袋固定放疗技术能使X轴误差减少，Y、Z轴无改善。在应用真空袋基础上，在患者胸部皮肤上标记水平参考线能提高精确度，减少摆位误差。

Application of Vacuum Pump in Radiation Therapy of Thoracic tumor

Objective To investigate the setup errors about application of vacuum pump in radiation therapy for the thoracic tumor.Methods Sixty patients of the thoracic tumor were divided three groups randomly.A group was without vacuum pump.B group was with reference level line on the thoracic skin.The verification films were taken per week from the first week to the end.A and B group in X-axis,Y-axis,Z-axis could be measured and C group were measured in Z-axis only.Results A group set up errors of X-axis,Y-axis,Z-axis were5.3±2.8 mm,3.8±2.3 mm,6.7±3.3 mm.B groups set up errors were 3.6±1.7 mm,3.2±1.8 mm,6.2±2.6 mm.C group set up errors of Z-axis were 3.1±1.6 mm.Conclusion Analysis of setup error in three groups.B group can help to reduce X-axis matched of A group by using vacuum pump.C group by using reference level line can help to reduce Z-axis errors matched with B group.