Design and Dose Distribution of Docking Applicator for an Intraoperative Radiation Thherapy

Chu, Sung Sil; Kim, Gwi Eon; Loh, John J L

Abstract

A docking intraoperative electron beam applicator system, which is easily docking in the collimator for a linear accelerator after setting a sterilized transparent cone on the tumor bearing area in the operation room, has been designed to optimize dose distribution and to improve the efficiency of radiation treatment method with linear accelerator. This applicator system consisted of collimator holder with shielded metals and docking cone with transparent acrylic cylinder. A number of technical innovations have been used in the design of this system, this docking cone gives a improving latral dose coverage at therapeutic volume. The position of 90% isodose curve under surface of 8 cm diameter cone was extended 4~7 mm at 12 MeV electron and the isodose measurements beneath the cone wall showed hot spots as great as 106% for acrylic cone. The leakage radiation dose to tissues outside the cone wall was reduced as 3~5% of output dose. A comprehensive set of dosimetric characteristics of the intraoperative radiation therapy applicator system is presented.