Korean J Med Phys.  2008 Dec;19(4):305-312.

Analysis of Accuracy of Apparent Activity According to Calibration Method for High Dose Rate Brachytherapy Source

• Huh HD
• Choi JH
• Choi SH
• Kim SH
• Kim WC
• Kim HJ
• Lee R
• Kim KB
• Hong SE
• Shin DO

Abstract

The aim of this study is to introduce the accuracy of Ir-192 source's apparent activity using the well-type chamber and the Farmer-type ionization chamber in the high dose rate brachytherapy. We measured the apparent activity of Ir-192 that each medical center in the country has and the apparent activity of calibration certificate provided by manufacturer is compared with that by our experimental measurement. The number of sources used for the activity comparison was 5. The accuracy of the measured activity was in the range of -2.8% to -1.0% and -2.1% to 0.2% for the Farmer-type chamber system (Jig) and for the well-type, respectively. The maximum difference was within 1.0% for comparison with two calibration's tool. Our results demonstrate that well-type chamber as wall as Farmer-type chamber is a appropriate system as the routine source calibration procedures in HDR brachytherapy. Whenever a new source is installed to use in clinics, by periods, a source calibration should be carried out.

Keyword

HDR Radiactive source strength; Jig phantom; Well-type ion chamber

MeSH Terms

Brachytherapy
Calibration