Development of Electronic Portal Imaging Device and Treatment Position Verification for Frationated Stereotatic Radiotherapy.

초록

The video based electronic portal image device, whcich could display the portal image in near real time, was implemnted to verify treatment position error in FSRT instead of portal film. Also development FSRT system was coposed of the sterotatic frame, frame mounting system and collimator cones. The verification of treatment position is very crucial in special therapies like FSRT. In general, the FSRT uses high dpse rate at small field size for treating small intracranial lesions. To evaluate quantitative positioning errors in FSRT, we used the first FSRT image as reference image and obtained the second FSRT image that was moved 2mm intentionally and detected intracranial contours after image processing. The generated 2mm error could be verified by overlapiing only contours of two images. Though this study, the radiation treatment efficiency could be improved by performing precise radiation therapy with a developed video base EPID and FSRT.