Indocyanine green angiographically well-defined choroidal neovascularization: angiographic patterns obtained using the scanning laser ophthalmoscope.

Several studies have shown that indocyanine green (ICG) angiography improves the detection of occult choroidal neovascularization (CNV). However, uncertainty remains about the angiographic patterns of CNV in ICG angiography. We examined the ICG angiographic findings of 104 patients (average age, 72.4 years) with newly diagnosed neovascular age-related macular degeneration and well-defined CNV in ICG angiography using the scanning laser ophthalmoscope. CNVs were grouped into one of three categories according to their appearance on biomicroscopy and fluorescein angiography: I, early CNV measuring less than half a disc diameter in size (7 eyes); II-1, advanced nonhemorrhagic CNV (44 eyes); II-2, advanced hemorrhagic CNV (29 eyes); and III, fibrovascular CNV (24 eyes). Of the 104 CNV, 36 demonstrated well-defined CNV and 68 ill-defined or occult CNV in fluorescein angiography. CNV in patients suffering from advanced nonhemorrhagic CNV (group II-1) demonstrated a thick, branching, early hyperfluorescent vascular pattern (27 of 44 eyes). In group III, CNV was depicted as thin, slightly branching vascular structures (16 of 24 eyes). In group I, dye leakage was found in all affected eyes, and in group II-2 it was present in 20 of 29 eyes. However, dye exudation was rare in group II-1 and group III. Feeder vessels were detected in 16 of 104 eyes. The structure and permeability of CNV can vary substantially in ICG angiography, depending on the stage of development or regression.