摘要
目的:利用带有电子射野影像装置(Electronic Portal Imaging Device,EPIDs)的Elekta-iViewGT系统对灯光野与射线野的一致性进行验证,以替代传统的手段,更可以达到节省人力物力和时间.方法:在加速器的能量为4MV,8MV,15MV光子线,在治疗模式下,剂量为40MU;分别以Elekta-iViewGTTM系统和剂量胶片法跟踪测量每个实验点的光野和射野重合度的改变.记录每个测量点的数据,分析灯光野与射线野的一致性的变化和比较两种方法之间的误差程度.结果:Elekta-iViewGTTM系统得出的数据和剂量胶片法分析取得的灯光野与射线野的一致性的参数之间误差比较不大于0.20mm.结论:可以利用Elekta-iViewGT系统对设备的灯光野与射线野的一致性验证,而且是较准确、有效、可靠和操作简单快捷以及数字化图像质量高、直观,替代传统的测验手段.
Background: To validate the alignment of light fields with radiation fields by using Elekta-iViewGT system, trying to provide an easy way for routine quality assurance to save time and reduce workload. Methods: The alignment of light fields with radiation fields was measured by using both Elekta-iViewGT systcm and films. 40 MU was delivered in each measurement for photon beams with energy of 4 MV, 8 MV and 15 MV, respectively. The results were then compared, and the associated deviations for these two methods were also calculated to evaluate their efficiency. Results: The alignment of light fields with radiation fields measured by Elekta-iViewGT system represents a good consistent with that measured by films (SD<0.20mm). Conclusion: Elekta-iViewGT system can be used as an easy tool to evaluate the alignment of light fields with radiation fields due to its ability to provide high quality digital images.
