LASER MICRO-BEAM CT SCANNING OF DOSIMETRY GELS

DESCRIPTION (Applicant's abstract verbatim): The long-term goal of this project is to provide radiation therapy departments and equipment vendors with a unique tool for accurate, fast and fully three-dimensional characterization of small radiotherapy fields, whether external beams or brachytherapy, with isotropic spatial resolution on the order of 100 microns. Our system is based on laser micro-beam CT scanning of tissue-equivalent dosimeter gels that change their optical properties in proportion to the absorbed dose. In Phase I we have designed, built and thoroughly tested two different prototypes of the micro-scanner, and have successfully proved the feasibility of our idea. In Phase II we will complete the research and development of the micro-scanner and will engineer various gel phantoms for micro-scanning. We will field-test our system in a clinical environment, and perform thorough dosimetry studies of various small fields and brachytherapy sources of clinical importance, comparing our technique with radiochromic film measurements. In Phase III we will license out the manufacture of our micro-scanner, and concentrate our efforts on manufacturing various gel dosimetry phantoms for high-resolution 3D dosimetry. We believe that our system will find widespread use in QA procedures and in patient treatment verification, wherever very high dose gradients are present in the treatment plan. PROPOSED COMMERCIAL APPLICATION: Not Available