A 500-kHz Localized Current Field Hyperthermia System for Use with Ophthalmic Plaque Radiotherapy

Abstract

Choroidal melanoma is the most common primary intraocular tumor in adults. Radiotherapy using an episcleral plaque containing an isotope such as ¹²⁵I has been demonstrated to be effective in the treatment of small choroidal melanomas (Brady et al. 1982; Lommatzsch 1983; Packer and Rotman 1980; Stallard 1966) and is being used with increasing frequency. This technique permits eradication of the tumor while preserving the eye. Although the initial tumor responses following plaque radiotherapy have been good, late complications are now being reported (Payne et al. 1986). These complications may include cataracts, vasculopathy of the retina and optic nerve, and neovascular glaucoma. The occurrence of late complications limits the radiation dose which may be delivered to larger tumors, particularly those in excess of 8 mm in height.