HISTOLOGICAL AND IMMUNOHISTOCHEMICAL STUDY OF IDIOPATHIC EPIRETINAL MEMBRANE

We used electron microscopy and light-microscopic immunohistochemistry of cellular and extracellular markers to characterize the cellular an d extracellular components of 15 surgically resected idiopathic epiret inal membranes (IEMs). Ten specimens from the eyes with posterior vitr eous detachment (PVD) consisted of inner limiting membrane, collagen l ayer and a flattened cell layer. Six out of the 10 specimens were also examined immunohistochemically, and fibronectin and type I, II, III a nd IV collagens were identified in a characteristic lamellar construct in the IEMs. On the other hand, 5 specimens obtained from the eyes wi thout PVD consisted mainly of a thick layer of collagen fibrils with o r without a flattened cell layer. Two of the 5 specimens were also exa mined immunohistochemically, and the collagen fibrils in the specimens were identified as type II collagen. Glial cells (glial fibrillary ac idic protein-immunoreactive cells) were also identified in 3 specimens . These results indicate that there are some variations in the IEMs.