[Dye leakage in indocyanine green fundus angiography of a laser photocoagulated lesion].

Argon green laser photocoagulation was performed on adult pigmented rabbit eyes at various intensities (parameters:500 microns spot size, 0.2 sec. exposure, and 70-, 100-, 150- and 200-mW power levels), and fluorescein and indocyanine green (ICG) angiography was performed within one hour after coagulation. Each coagulum of ICG angiography was hypofluorescent in the early phase and brightly fluorescent in the late phase. The fluorescein and ICG dyes spread from the periphery to the center in the moderate and large coagula. The characteristic finding of ICG angiography was expansion of ICG dye around the coagulum, regardless of the degree of the coagulation. This ICG leakage was intra-choroidal because there was no fluorescein dye leakage around the coagulum. We concluded that the ICG dye leakage shows damage to the choroidal vessels due to laser photocoagulation, and is not related to the barrier function of the retinal pigment epithelium.