The feasibility study and characterization of a two-dimensional diode array in “magic phantom” for high dose rate brachytherapy quality assurance

High dose rate (HDR) brachytherapy is a radiation treatment technique capable of delivering

large dose rates to the tumor. Radiation is delivered using remote afterloaders to drive highly

active sources (commonly 192Ir with an air KERMA strength range between 20 000 and 40 000 U,

where 1 U = 1 μGy m2/h in air) through applicators directly into the patient’s prescribed region of

treatment. Due to the obvious ramifications of incorrect treatment while using such an active source,

it is essential that there are methods for quality assurance (QA) that can directly and accurately verify

the treatment plan and the functionality of the remote afterloader. This paper describes the feasibility

study of a QA system for HDR brachytherapy using a phantom based two-dimensional 11 × 11

epitaxial diode array, named “magic phantom.”