Clinicopathological correlation of macular idiopathic polypoidal choroidal vasculopathy

Abstract

Abstract: : Purpose: To describe the histopathologic findings of macular idiopathic polypoidal choroidal vasculopathy(IPCV). Methods: A 66 year old female with macular polypoidal choroidal vasculopathy suffered an acute submacular hemorrhage. Fluorescein angiography, indocyanine green angiography, and optical coherence tomography before and after the hemorrhage demonstrated a typical IPCV lesion. She underwent vitrectomy surgery and removal of subretinal polypoidal lesion. Histopathological sections were studied with special stains and immunohistochemistry. Results: Histopathological examination of the specimen revealed a sinusoidal vascular proliferation under Bruch’s membrane with an intact overlying retinal pigment epithelial cell layer. The mass consisted of degenerated red blood cells, fibrin, occasional myofibroblasts (SMA positive) and a conglomerate of communicating sinusoidal neovascular spaces that were lined by a focally discontinuous row of flat endothelial cells (factor 8 positive) deposited directly on the fibrin without a vascular matrix (lack of reticulin and SMA staining). These endothelial cells had a low proliferative rate (Ki 67 positivity of approximately 3%). Conclusions: Macular polypoidal choroidal vasculopathy appears to be a form of choroidal neovascularization located under the retinal pigment epithelium with a slow growth rate. The neovascular lesion histologically differs from typical choroidal neovascularization in age related macular degeneration by its minimal fibrous component and sinusoidal pattern.

Keywords: choroid: neovascularization • pathology: human