ICRU Report 72, Dosimetry of Beta Rays and Low-Energy Photons for Brachytherapy with Sealed Sources


This Report examines the dosimetry of beta-ray and low-energy photon-emitting sealed brachytherapy sources, specifically the following: (a) planar and concave sources of beta rays from 90Sr—90Y and 106Ru—106,Rh, mainly used for ophthalmic plaques; (b) seed and wire sources of beta rays from 90Sr—90Y,90Y, and 32P, and shell sources of 32P, for applications in intravascular brachytherapy; and (c) seed sources of low-energy photons from 125I and 103Pd, for use in ophthalmic plaques and as interstitial implants.

The specification and calibration of the sources are covered, and the methods of calculation and measurement for the determination of single-source dose distributions for radiotherapy are described in detail. An up-to-date compilation of useful dosimetric reference data for a number of both the beta-ray and low-energy photon sources is presented. For planar and concave sources of beta rays, relative axial depth-dose data are presented. For line (seed and wire) beta-ray sources,single-source dosimetric data are presented together with there commended formalism for calculation of dose distributions based on these data. For selected low-energy photon-emitting source models, single-source dosimetric data are given based on the recommended formalism adopted by the American Association of Physicists in Medicine. For reporting therapeutic irradiations, it is recommended that the doses are specified in relation to anatomical references. Clinical examples illustrating how to apply the recommendations are presented for uveal melanoma and endovascular brachytherapy.