Early vascular changes induced by transpupillary thermotherapy of choroidal neovascularization.

Abstract

To study early direct effects of transpupillary thermotherapy (TTT) on choroidal neovascularization (CNV) and choroid. Retrospective, noncomparative interventional case series. Sixty-four eyes with subfoveal CNV. TTT was delivered using a diode laser at 810 nm through a contact lens. Exposure time was 60 seconds with a power/diameter ratio of 247 mW/mm. The end point was an invisible treatment with no color change at the retina level. Fluorescein and indocyanine green angiographic findings within 1 hour, and at 1, 2, and 4 weeks after TTT. Fluorescein angiography (FA) and indocyanine green angiography (ICGA) performed within 1 hour after TTT showed increased leakage of CNV and choroidal vessels. Follow-up at 1 and 2 weeks demonstrated a hypofluorescent area corresponding to the laser spot and absence of angiographic leakage seen on FA and ICGA. At 4 weeks after TTT, FA showed mottled hypofluorescence-hyperfluorescence of the TTT-treated area and absence of angiographic leakage. TTT induces a characteristic dynamic sequence of vascular changes. Treatment with TTT can lead to absence of angiographic (FA and ICGA) leakage for 4 weeks. Determination of the long-term efficacy and visual implications awaits the results of clinical trials.