Thermoradiotherapy for intraocular tumors.

We have developed and used a thermoradiotherapy (TRT) plaque to treat choroidal melanoma (Greene strain) in rabbits. A dual-therapy scleral plaque delivers localized hyperthermia (4.8-gigahertz microwave) and ionizing radiation (iodine I 125). Transscleral treatment involves placement of a TRT plaque on bare sclera at the base of an intraocular tumor. Therapeutic doses of ionizing and hyperthermic radiation are then simultaneously delivered to the intraocular tumor. Sparing of normal ocular structures outside the treatment area after the combined therapy has been noted on clinical, gross, and histologic examinations. Our study suggests that the TRT plaque described satisfies the requirements for dual-modality treatment of choroidal melanoma.