Staging of idiopathic choroidal neovascularization by optical coherence tomography

Purpose: To assess the clinical course of idiopathic choroidal neovascularization (ICNV) by optical coherence tomography (OCT). Methods: Thirty-two patients with a clinical diagnosis of ICNV were examined between December 1995 and October 1999. The ages of the patients ranged from 18 to 53 (mean 35.9) years, and the mean period of observation was 5.8 months. Color fundus photography, fluorescein angiography, Indocyanine green angiography, and OCT were performed. The stage of the ICNV was classified as active, intermediate, or cicatricial, based on past history, fundus findings, and fluorescein angiography (FAG). The characteristic OCT images at these three stages were determined. Results: OCT revealed that there were characteristic tomographic images of the choroidal neovascularization (CNV) at each stage. In the active sta-e, OCT revealed the CNV as a highly reflective, multi-layered area protruding into the subretinal space. In the intermediate stage, the reflectivity of the CNV became stronger and its margin in the subretinal space became smooth. With regression of the ICNV, the lesions consisted of two different areas: a most reflective area corresponding to the fibrotic changes of the CNV (imaged white in OCT images), and a reddish highly reflective area representing a compound protrusion of the CNV. In the cicatricial stage, the ICNV was observed as a moderately high reflective area covered by a dome-shaped highly reflective layer corresponding to the retinal pigment epithelium. Conclusion: These findings demonstrated clearly the changes in the OCT images during the development and regression of ICNV. OCT was useful for following the clinical course and understanding the mechanism of the CNV regression.