Definition

A polycarbonate-based semicylindrical plaque impregnated with yttrium Y 90 with radioisotopic and antineoplastic activities. An yttrium-90 polycarbonate brachytherapy plaque may be applied to a tumor site with a special brachytherapy applicator for a predetermined interval of time, selectively delivering a cytotoxic dose of beta-emitting yttrium Y 90.