Transpupillary thermotherapy for the treatment of occult CNV in age‐related macular degeneration: a prospective randomized controlled pilot study

Abstract
To evaluate whether transpupillary thermotherapy (TTT) reduces the risk of moderate visual loss in patients with occult choroidal neovascularization (CNV) secondary to age-related macular degeneration (AMD). A group of 25 patients were recruited and randomized into TTT or placebo groups. Patients were included if they had a subfoveal purely or predominantly (> 50%) occult CNV secondary to AMD with best corrected visual acuity (BCVA) of 6/60 or better and the lesion was not larger than 4.5 mm. Treatment was carried out using an 810-nm Oculight diode laser with a fixed spot size covering the whole lesion according to the standard protocol. The same procedure was used for the control group, except that the power was set at zero. The patients were followed up at 6 weeks, 3 months and then every 6 months for up to 2 years. A maximum of three treatments were administered in both groups if there was evidence of persistent leakage from CNV. At the 12-month follow-up, there was no significant difference in the mean values for BCVA distance and near or contrast sensitivity between the treatment and control groups. The Mann-Whitney test was used to assess the differences in BCVA and contrast sensitivity between the groups, both at baseline and at the 12-month follow-up. No statistically significant difference was found; both groups lost on average two lines of BCVA. Transpupillary thermotherapy appeared to have been of no benefit in preventing further visual loss in patients with occult CNV in this pilot study.