Standard Calibration of 137Cs Sources Used in Brachytherapy

Solimanian, A; Alipoor, A; Ghafoori, M

Standard Calibration of 137Cs Sources Used in Brachytherapy

Document Type : Research Paper

Authors

A Solimanian

A Alipoor

M Ghafoori

Abstract

The increasing application of brachytherapy techniques in radiotherapy centers necessitates setting up a calibration system for the relevant radioactive sources. Accordingly, the strength of a low dose rate (LDR) ¹³⁷Cs source, with specifications common to similar radioactive gamma ray sources used in afterloading brachytherapy equipment, is measured free in air in terms of air kerma by a standard spherical ionization chamber. Two different kinds of well type ionization chambers are then calibrated by the aid of the calibrated ¹³⁷Cs source. The overall uncertainty of the air kerma determination of similar ¹³⁷Cs sources by the calibrated well type chambers is estimated not to exceed 4%.

Highlights

F.M. Khan, "The Physics of Radiation Therapy," 3^rd edition, Lippincott Williams and Wilkins, USA (2003).
International atomic energy agency, "Calibration of photon and beta sources used in brachytherapy," IAEA – TECDOC – 1274, March (2002).
American association of physicists in medicine, AAPM Task Group 56: Code of Practice for brachytherapy physics, Med. Phys., vol. 24, No. 10, 1557-1598 (1997).

Keywords

brachytherapy

radioactive source 137Cs

calibration

reference air kerma rate

well type chamber

radiotherapy

F.M. Khan, "The Physics of Radiation Therapy," 3^rd edition, Lippincott Williams and Wilkins, USA (2003).
International atomic energy agency, "Calibration of photon and beta sources used in brachytherapy," IAEA – TECDOC – 1274, March (2002).
American association of physicists in medicine, AAPM Task Group 56: Code of Practice for brachytherapy physics, Med. Phys., vol. 24, No. 10, 1557-1598 (1997).