Low power vs standard power transpupillary thermotherapy in patients with age-related macular degeneration and subfoveal choroidal neovascularization ineligible for photodynamic therapy.

To assess the effect of standard power vs low power transpupillary thermotherapy (TTT) in patients with active subfoveal choroidal neovascularization secondary to age-related macular degeneration ineligible for photodynamic therapy (PDT) by original treatment of age-related macular degeneration with photodynamic therapy (TAP) study group recommendations. Retrospective review of 79 patients with active predominantly occult subfoveal choroidal neovascularization or predominantly classic subfoveal choroidal neovascularization but Snellen visual acuity <20/200. All patients were treated with TTT administered via a Mainster wide field fundus contact lens with a retinal power/diameter coefficient of 248 mW/mm in the standard power (n=27) and 181 mW/mm in the low power group (n=52). The primary outcome was stabilization (<1 Snellen line change) or improvement (two or more Snellen lines) in visual acuity. Clinical and fluorescein angiographic resolution of overlying exudation was documented. At 24 month follow-up, 17 patients (63%) in the standard power and 36 patients (69%) in the low power group achieved stable or improved vision. Improved vision (mean three lines) was observed in 22% of the standard power and 23% of the low power group. Overlying exudation was reduced clinically with minimal or no leakage on fluorescein angiogram in 85% of standard power and 90% of low power group. Subgroup analysis in the low power group demonstrated a visual benefit in patients with subfoveal lesions, which had any classic component. Low power TTT is as effective as standard power in stabilizing or improving vision and reducing overlying exudation in patients with active subfoveal choroidal neovascularization ineligible for PDT.