LOW-DOSE RADIATION ON THE SUBFOVEAL NEOVA SCULAR MEMBRANES (SNVM) IN AGE-RELATED MACULAR DEGENERATION

Aim of the study The aim of this study is to test the effect of low do se radiation on the subfoveal neovascular membranes (SNVM) and to anal yse visual acuity in age-related macular degeneration. Methods and pat ients From November 1993 through to August 1994, 10 patients,on the on e hand, were given a dose of 5 Gy followed by controls 6 weeks and 6 m onths later. On the other hand, 21 patients were treated with a dose o f 8 Gy and were subjected to controls 6 weeks later. Before the radiot herapy and during the control sessions, all patients were required to be measured for different parameters of visual acuity and to receive a simultaneous fluorescein and indocyanine green angiography. The radio therapy was done by a linear accelerator 6 MeV and through a lateral p ort 3 x 4 cm in half beam technic. Results In the 5 Gy group, no chang es in the parameters for visual acuity were noted in most cases after 6 months. In 9 of the cases, the membranes had increased in size and i n 1 case, they had remained unchanged. In the 8 Gy group, no changes i n the visual acuity or in the membrane size were diagnosed. Of all the patients treated, only one refused the angiography control. Discussio n and conclusions Given the low dose used and the period of observatio n, the visual acuity of all patients remained stable. The size of the membranes increased in most cases for those 5 Gy patients and in this respect, no changes at all were noted in the 8 Gy patients. In order t o better evaluate the potential of radiotherapy, this study must be pu rsued and coupled with further studies analysing the effect of differe nt doses on patients.