A Study of Digital Portal Image for Automatic Verification

초록

In this paper, Extrinsic image feature by using markers on a scale board is used to match simulator image and portal image. CCD camera, image grabber and pentium PC can acquire portal image after therapy radiation was converted into light by a metal/fluorescent screen. We measured the distance and angle between the marked point and the iso-center, as well as the distance between the newly relocated point and the iso-center and find the ratio between these two distances. Then we can match the newly acquired portal image and the simulator image for verification of the patient's treatment location. Also, Field edge was added to the original portal image for checking the anatomical treatment verification. We also display the systematic error data between simulator and linear accelerator with colors on the monitor.