【摘要】 目的 评估RIT113软件验证加速器等中心精度的可行性。方法 结合电子射野影像装置（Electronics Portal Image Device,EPID）采集的图像，测试RIT113软件分析6 MV均整器模式（Flatten Filter,FF）和6 MV无均整器模式（Flatten FilterFree,FFF）两种不同能量X射线下等中心的重复性和准确性。重复性：在保持小球位置不动，机架、治疗床和准直器角度均为0°的情况下重复采集10次EPID图像，使用RIT113软件分析小球位置变化情况。准确性：LAT（左右）、VRT（上下）、LNG（左右）方向上分别引入已知位移（-1.0～1.0mm），步径0.25mm，使用RIT113软件对采集到的图像进行分析，得到测量结果与实际引入位移的偏差。结果 RIT113软件在6 MV FF X射线情况下验证加速器等中心时，在LAT和LNG方向上归一后重复性分别为0.994±0.031和0.998±0.009;6MVFFFX射线情况下，在LAT和LNG方向上归一后重复性分别为1.000±0.009和1.001±0.014。RIT113软件在6 MV FF X射线下的LAT、LNG和VRT方向上准确性分别为（0.026±0.005）、（0.041±0.014）和（0.018±0.009）mm，而在6 MV FFF X射线下的LAT、LNG和VRT方向上准确性分别为（0.015±0.008）、（0.023±0.017）和（0.015±0.014）mm。结论 RIT113软件在加速器等中心验证上重复性和准确性良好，能够满足临床需求。更多还原

【Abstract】 Objective To evaluate the feasibility of RIT113 software for verifying the accuracy of accelerator isocenter.Methods The repeatability and accuracy of RIT113 isocenter verification with 6 MV Flatten Filter(FF) and 6 MV Flatten Filter Free(FFF) X-ray were tested by combining the images acquired by an electronics portal image device(EPID).Repeatability:Images were acquired using an EPID for 10 times without altering the position of the ball with the angle of gantry,couch and collimator all 0°,RIT113 software was used to analyze the changes of the ball position.Accuracy:The known shifts were applied to the ball in lateral(LAT),lengthways(LNG) and vertical(VRT) direction from-1.0 mm to +1.0 mm in steps of 0.25 mm.RIT113software was used to analyze the collected images acquired from EPID to obtain the deviation between the measurement results and the actual shift.Results The normalized repeatability of RIT113 isocenter verification with 6 MV X-rays in LAT and LNG were respectively 0.994±0.031 and 0.998±0.009.The normalized repeatability of RIT113 isocenter verification with 6 MV FFF X-rays in LAT and LNG were respectively 1.000±0.009 and 1.001±0.014.The accuracy of RIT113 isocenter verification with 6 MV FF X-rays in LAT,LNG and VRT were respectively(0.026±0.005),(0.041±0.014) and(0.018±0.009) mm.The accuracy of RIT113isocenter verification with 6 MV FFF X-rays in LAT,LNG and VRT were(0.015±0.008),(0.023±0.017) and(0.015±0.014) mm.Conclusion RIT113 software has good repeatability and accuracy in accelerator and other center validation,and can meet clinical needs.更多还原