Fabrication of Cesium-137 Brachytherapy Sources Using Vitrification Technology

Abstract 137Cs source in solid matrix encapsulated in stainless-steel at MBq (mCi) levels are widely used as brachytherapy sources for the treatment of carcinoma of cervix uteri. This article describes the large-scale preparation of such sources. The process of fabrication includes vitrification of 137Cs-sodium borosilicate glass, its transformation into spheres of 5–6 mm diameter, casting of glass spheres into a cylinder of 1.5mm (ϕ) × 80 mm (l) in a platinum mould, cutting of the moulds into 5-mm-long pieces, silver coating on the sources, and finally, encapsulation in stainless steel capsules. Development of safety precautions used to trap 137Cs escaping during borosilicate glass preparation is also described. The leach rates of the radioactive sources prepared by the above technology were within permissible limits, and the sources could be used for encapsulation in stainless steel capsules and supplied for brachytherapy applications. This development was aimed at promoting the potential utility of 137...