Purpose: To evaluate ophthalmic plaque radiotherapy for the treatment of subretinal neovascularization associated with age-related macular degeneration.
Methods: In a prospective phase I clinical trial, we treated 23 patients (23 eyes) with ophthalmic plaque radiotherapy for subfoveal exudative macular degeneration. Palladium 103 ophthalmic plaque brachytherapy was delivered to a retinal apex dose of 1,250 to 2,362 cGy (rad). Early Treatment Diabetic Retinopathy Study type visual acuity determinations, ophthalmic examinations, and angiography were performed before and after treatment. Clinical evaluations were performed in a nonrandomized and unmasked fashion.
Results: Patients were followed up for a mean (+/-SD) of 19 +/- 10.7 months (range, 3 to 37 months). Six months after radiation therapy, three (16%) of 19 eyes had lost 3 or more lines of best-corrected visual acuity; 12 months after radiation therapy, four eyes (31% of 13 eyes), and 24 months after radiation therapy, only two (22% of nine eyes) lost 3 or more lines of visual acuity. No eye suffered sudden irreversible loss of central vision. No radiation retinopathy, optic neuropathy, or cataract could be attributed to radiotherapy within this follow-up period.
Conclusion: Ophthalmic plaque radiotherapy can be used to treat neovascular age-related macular degeneration. In contrast to external beam radiotherapy, ophthalmic plaque radiotherapy is a unilateral treatment, which allows a larger dose to be delivered to the macula with less irradiation of normal ocular structures. We have found no sight-limiting complications at the doses, dose rates, and follow-up evaluated in this study.