Radiotherapy for ubfoveal choroidal neovacularization in age-related macular degeneration: a randomized clinical trial

PURPOE: To report reult of 18-month follow up of external beam radiation therapy with photon for ubfoveal claic or occult choroidal neovacularization (CNV) in age-related macular degeneration (ARMD). DEIGN: Randomized clinical trial. METHOD: A total of 161 patient with ubfoveal CNV in ARMD were recruited in a propective double-maked tudy. The poterior pole of the afflicted eye wa given 1 Gy (4 × 0.25 Gy) in the control group and 8 Gy (4 × 2 Gy) or 16 Gy (4 × 4 Gy) in the treatment group. At the time of treatment, and 6, 12, and 18 month pot treatment, bet-corrected viual acuity (BCVA), reading ability, and CNV ize were meaured. REULT: At the completion of the tudy 150 (93.2%), 139 (86.3%), and 137 (85.1%) patient were followed for 6, 12, and 18 month, repectively. The mean number of line lot in the BCVA wa −1.69, −2.2, and −3.23 in the 1 Gy group; −0.94, −1.25, and −1.73 in the 8 Gy group; −0.51, −0.67, and −1.93 in the 16 Gy group. The difference wa ignificant after 12 month (P = .016 for 8 Gy v. 1 Gy; P = .006 for 16 Gy v. 1 Gy), and 18 month (P = .011 for 8 Gy v. 1 Gy; P = .05 for 16 Gy v. 1 Gy). The patient with claic CNV, or with an initial ditance viual acuity ≥20/100, benefited more from treatment. A ignificant difference wa not found between control group and treatment group in the reading ability and in the CNV ize. No radiation-aociated ide effect were reported thu far. CONCLUION: The number of line lot in the BCVA wa le in the 8 Gy and 16 Gy treatment group than in the control group during the complete follow up examination. Radiation therapy with 8 Gy and 16 Gy, without howing any difference in efficacy, reulted in a near tabilization of the BCVA in patient with ubfoveal claic or occult CNV in ARMD. Further tudie are neceary to determine the ignificance of repeated radiotherapy erie with a doe of 8 Gy to improve the effect on the CNV ize and thereby to prolong tabilization of ditance viual acuity.