Pennington E C, Jani S K, Wen B C
Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City 52242.
Med Phys. 1988 Sep-Oct;15(5):763-5. doi: 10.1118/1.596191.
The leakage characteristics of electron applicators on our Clinac 2500 linear accelerator have been measured. The leakage radiation in the patient plane and at the surface of the electron applicators has been measured for applicator sizes from 6 cm X 6 cm to 25 cm X 25 cm and beam energies from 6 to 22 MeV. For certain applicator/energy combinations the leakage radiation was significant. The leakage radiation, relative to the central axis dose, was found to be up to 7% in the patient plane and up to 39% at the applicator surface. Reducing the collimator setting or adding lead at select locations on the applicator surface was effective in reducing the magnitude of the radiation leakage.
我们已对Clinac 2500直线加速器上电子限光筒的泄漏特性进行了测量。针对尺寸从6 cm×6 cm至25 cm×25 cm的限光筒以及能量从6至22 MeV的射束，测量了患者平面和电子限光筒表面的泄漏辐射。对于某些限光筒/能量组合，泄漏辐射较为显著。相对于中心轴剂量，在患者平面中泄漏辐射高达7%，在限光筒表面则高达39%。减小准直器设置或在限光筒表面的选定位置添加铅，可有效降低辐射泄漏的幅度。
