摘要
目的:探讨电子射野影像系统(EPID)在加速器辐射野与灯光野一致性测量中的应用。方法:使用Varian 600CD医用电子直线加速器,6MV X射线能量,使用水平尺,确认机架位于0°,准直器0°,提前校准照射野中心和投影十字线,将厂家自带的金属点十字影子板插在加速器机头上,金属点十字影子板上两金点之间在SSD=100cm处的投影距离为1cm,调整机头十字线与金属十字线投影重合;打开EPID测量板,在SSD=100cm条件下,灯光野分别开到标准野(10×10)cm,(15×15)cm,(20×20)cm,(25×25)cm,剂量率100MU/M,曝光5MU;得到各标准野的辐射野,两金属点之间标准距离1cm,使用测量软件分别分别测量辐射野各方向距离。结果:辐射野各方向偏差较小,均小于±2mm。结论:EPID射野影像检测方式适合于临床质控检验,可用于加速器辐射野与灯光野一致性的质控测量,减少工作量。
objective： to study the electron beam radiation imaging system （EPID） in the accelerator field and light field consistency measurement application. Methods： use the Varian 600 CD medical electron linear accelerator, 6 mv X-ray energy, using a spirit level, confirm the frame in 0 °, collimator 0°, calibration center of radiation field and projection reticle ahead of schedule, the manufacturer＇s own point of metal cross shadow plate inserted in the accelerator on the nose, between metal cross shadow board two gold in SSD = 100 cm of the projection distance is 1 cm, adjust the nose reticle and metal reticle projection overlap; Open the EPID measurement board, under the condition of the SSD = 100 cm, light field respectively to the standard open wild 10 cm by 10 cm, （ 15 × 15 ） cm, （20 × 20） cm and （25 × 25） cm and 100 mu/M dose rate, exposure of 5 mu; Get radiation in the field of the wild, the standard distance between two metal point 1 cm, use measurement software measured radiation field from different directions, respectively. Results： the radiation field in each direction deviation is small, less than ＋ / - 2 mm. Conclusions： EPID beam image detection method for clinical quality control inspection, can be used in the accelerator radiation field and the light field consistent quality control measurements, reduce the workload.
出处
《中国医学物理学杂志》
CSCD
2013年第2期4001-4003,共3页
Chinese Journal of Medical Physics
关键词
电子射野影像系统
质量控制
辐射野与灯光野
electronic portal imaging device
quality control
the radiation field and the light field
