EXTERNAL RADIOTHERAPY IN MACULAR DEGENERATION - TECHNIQUE AND PRELIMINARY SUBJECTIVE RESPONSE

Purpose: This study attempted to assess the toxicity and possible prel iminary benefits from the administration of low-dose external beam irr adiation for age-related macular degeneration (ARMD). The premise of t he treatment is that radiation induces regression and/or promotes inac tivation of the subretinal neovasculature which would result in reabso rption of fluid and blood. This would reduce the risk for further leak age or bleeding, as well as subretinal fibrosis. Consequently, the ben eficial effect could be translated into stabilization of visual acuity and prevention of progression of the wet ARMD with the possibility fo r slight improvement. Methods and Materials: Allegheny University Depa rtment of Radiation Oncology treated 41 patients prospectively from Ja nuary through October 1995 with low-dose irradiation for wet-type macu lar degeneration. A total of 39 patients were treated with a total dos e of 14.4 Gy in eight fractions of 1.8 Gy/fraction over 10-13 elapsed days. The first two patients were treated with a total dose of 10 Gy i n fivefractions of 2 Gy. Patients were evaluated at 2-3 weeks and 2-3 months. Some of the patients (36.7%) had laser treatments in the study eye: 21.9% (9) once, 5% (2) twice, 9.7% (4) thrice or more. Subjectiv e visual acuity and toxicity data were collected on all patients. Resu lts: At 2-3 weeks after treatment 29 patients (70%) retained their vis ual acuity without change, 10 (24.5%) stated they had improved vision, and 2 (4.8%) stated their vision continued to decrease. At 2-3 months after treatment, 27 patients (65.8%) had no change in their vision, 1 1 (27%) had an improvement in their vision, and 3 (7.2%) had a decreas e in visual acuity. Six patients of 41 in the treated group had acute transient side effects. Conclusion: Our observations in this group of 41 patients support the conclusion that many patients will have improv ed or stable vision after treatment with low-dose irradiation for age- related met-type macular degeneration. Copyright (C) 1996 Elsevier Sci ence Inc.