Long-term results after external radiotherapy in age-related macular degeneration. A prospective study

To prospectively evaluate the short- and long-term efficacy of external radiotherapy (RT) in patients with age-related macular degeneration (AMD) by comparing two different dose schedules.

In this prospective, nonrandomized, comparative study including 80 patients, the efficacy of external RT with a total dose of 14.4 Gy (group A, n = 40) and 25.2 Gy (group B, n = 40) was compared. Patients of group A were irradiated between September 1995 and July 1996, patients of group B between August 1996 and November 1997. 67 patients presented with occult choroidal neovascularization (CNV), 13 with classic subfoveal lesions. Complete ophthalmologic investigation was performed before RT, at intervals of 3 months during the 1st year after RT, and of 6 months thereafter.

12 months after RT, vision deteriorated in 85% (14.4 Gy) and 65% (25.2 Gy) of patients. Central visual field decreased with both dose schedules. There was no morphological benefit in neovascular changes. After 48 months, complete follow-up was possible in 46 patients who showed a significant loss of vision similar to the natural course of AMD.

External RT of AMD with 14.4 Gy as well as with the escalated dose of 25.2 Gy showed a poor beneficial outcome after 6 and 12 months, respectively. After a follow-up of 4 years, visual outcome in irradiated patients was similar to the natural course of the disease. A conspicuous efficacy of RT in prevention of blindness could not be demonstrated.