RADIOTHERAPY FOR AGE-RELATED MACULAR DEGENERATION - PRELIMINARY-RESULTS OF A POTENTIALLY NEW TREATMENT

Purpose: Neovascular macular degeneration is the leading cause of seve re blindness in North America today, Limited treatments are available for this disease process, A Phase I/II study was performed to determin e the toxicity and efficacy of external beam radiotherapy in patients with age-related subfoveal neovascularization. Methods and Materials: Between March 1994 and June 1995, 52 patients with a mean age of 80 (6 0-92) mere enrolled. These patients were either not eligible or were p oor candidates for laser photocoagulation, primarily because of the su bfoveal location of the neovascularization, Initial visual acuities ra nged from 20 out of 32 to finger counting at 3 feet, All patients unde rwent fluorescein angiographic evaluation and documentation of their n eovascular disease prior to irradiation, Patients were treated with a single lateral 4- or 6-MV photon beam, to a dose of 14-15 Gy in eight fractions over 10 days, The field size averaged 5 x 3 cm. Results: No significant acute morbidity was noted, All patients underwent ophthalm ic examinations and repeat angiography at 1 and 3 months posttreatment and then at 3-month intervals, With a mean follow-up of 7 months (3-1 8 months), 41 patients (79%) are within two lines of their pretreatmen t visual acuity, On angiographic imaging, there was stabilization of s ubfoveal neovascular membranes in 34 patients (65%), New neovascular m embranes have been noted in five patients. Conclusions: It appears tha t radiotherapy can affect active subretinal neovascularization, but it is unlikely to prevent new neovascular events produced by this chroni c disease, Further investigation is warranted. Copyright (C) 1996 Else vier Science Inc.