TruebeamTM直线加速器的性能检测和质量保证

摘要

Objective: To set up the procedures of performance test and quality assurance of TruebeamTM by measuring the mechanical parameters, field parameters, imaging isocenter and respiratory gating systems. Methods:Utilize level and graph paper to test the mechanical parameters; Utilize the film, 3D water tank and dosimeter to measure the corresponding field parameters;Utilize IsocCal phantom to test the shift of imaging isocenter and to use dosimeter to verify the beam on accuracy of respiratory gating systems. Results:All of the tested mechanical parameters were within the tolerance. The coincidence of light field and radiation field was less than 1.2 mm. The flatness was less than 105%except for the flattening filter free beam and the symmetry was less than 102%. The absolute dose error was less than 1%. The shift of imaging isocenter was less than 3 mm and the dose error was within 0.5‰when the respiratory gating function was implemented. Conclusion:TruebeamTM possesses superior mechanical performance and is very suitable to carry out complicated radiotherapy techniques.%目的：通过对TruebeamTM直线加速器的机械参数、射野参数以及影像等中心和呼吸门控系统等进行测试，探讨该加速器性能检测和质量保证的内容及方法。方法：使用水平仪和坐标纸等测量机器的相关机械参数；使用胶片、三维水箱和剂量仪等测量机器的相关射野参数；使用IsocCal模体验证影像等中心偏移；使用剂量仪验证呼吸门控出束准确性。结果：所有测试的机械参数均在误差允许范围之内；在射野参数方面，光野射野一致性误差＜1.2 mm，射束的平坦度＜105%(非均整射束除外)，对称性＜102%，绝对剂量误差＜1%；影像等中心偏差＜3 mm；实施呼吸门控时其剂量偏差＜0.5‰。结论：TruebeamTM直线加速器性能优越，适合开展复杂的放射治疗技术。