OBJECTIVE Evaluation of choroidal alterations associated with idiopathic choroidal neovascularization (ICNV) and the possible relation between this affection and Multifocal Choroidopathies (MC). METHODS The authors analysed, using high definition videoangiography, the choroidal findings in 21 consecutive patients affected by ICNV (7 males and 14 females; 19-46 years; mean age: 31.8 years); with a follow-up at 5-30 months (mean 13 months). Moreover, a retrospective study of 20 cases of ICNV (11 males and 9 females; age: 17-39 years; mean age: 29.3 years) with a follow-up at 6-11 years (mean 8.9), was performed. RESULTS In 7 eyes, the indocyanine green angiography (ICGA) showed choroidal hypofluorescent spots similar to those observed in MC (in 3 cases even in the fellow unaffected eye), in 2 of them the regression of the spots was observed after steroid therapy. In 2 eyes, the ICGA revealed hyperfluorescent spots; in one of them the complete regression of the spots after oral cyprofloxacine was observed. In 6 patients (10 eyes), choroidal permeability alterations could be visualized (in 4 cases even in the unaffected eye). CONCLUSIONS The indocyanine green angiographic findings (hypo and hyperfluorescent spots, choroidal permeability alterations) could support the theory of Gass which considers that ICNV is not idiopathic but secondary to a widespread choroidal inflammatory disease. The similarity of the ICGA alterations in ICNV and MC, the observation that cases of ICNV would become MC in the follow-up, could allow the hypothesis of a close connection between these two affections.