[Indocyanine green angiography with an infrared scanning laser ophthalmoscope. Initial clinical experiences]

Abstract

This report summarizes our first clinical results with indocyanine green angiography using an infrared scanning laser ophthalmoscope (IR-SLO) is equipped with an infrared laser diode of 780 nm and a barrier filter of 830 nm. Angiographies are recorded on videotape and images simultaneously digitized and saved on the disk. For each examination, 25 mg of Indocyanine Green (ICG), dissolved in 5 ml aqueous solvent, is injected into a cubital vein. We came to the following conclusions: First, the detection of subretinal neovascular membranes is certainly improved, especially for ill-defined membranes when the exact demarcation cannot be seen either because of diffuse exudation of fluorescein or because of the pigment epithelium. Second, we were able to demonstrate the lobular structure of the choriocapillary layer and prove that the acute form of posterior multifocal placoid pigment epitheliopathy is derived from a defect in this layer. Third, examination of the meaning sites of retinal and choroidal vessels revealed the additive fluorescence of ICG, which had not previously been known and which is bound to complicate tremendously the analysis of quantitative measurements. Our results prove that this new method is a useful diagnostic procedure for both the clinical routine and research. The different properties of fluorescein and indocyanine green prevent competition of these dyes. ICG represents a true completion.