Subretinal membranes in proliferative vitreoretinopathy. An immunohistochemical study.

Proliferative vitreoretinopathy may be associated with taut subretinal membranes (SRMs) that prevent retinal reattachment. Light microscopic and immunohistochemical procedures were used to identify the cell composition of 15 surgically excised SRMs. Anti glial fibrillary acidic protein (anti-GFAP) and anti S-100 protein stainings were used to examine the distribution of glial cells, and antikeratin staining was used to investigate the distribution of epithelial cells. Our findings confirm the presence of retinal pigment epithelium (RPE) and glial cells in human SRMs. A semiquantitative evaluation of the immunohistochemical studies demonstrated the prevailing role of cells derived from the RPE (48.4%). The glial component of the SRMs appeared to be smaller than in epiretinal membranes, but was not negligible (30.8%). A high incidence (26.6%) of damaged external retina adhered to the SRMs was also observed.