Search

Purpose: We investigated the immunohistochemical features of surgically resected idiopathic epiretinal membranes(ERMs) and secondary ERMs with regard to posterior vitreous detachment(PVD)., Methods: Six specimens of idiopathic epiretinal membranes(3 eyes with complete PVD, 2 eyes with partial PVD, and one eye with no PVD) and 3 specimens of secondary ERMs(all eyes with complete PVD) were immunohistochemically studied. We used type I, II, III, IV collagen and fibronectin to study extracellular components, and glial fibrillary acidic protein(GFAP), S 100 protein, vimentin, and so forth to study cellular components., Results: All the specimens of idiopathic ERMs had the major components of the lamellar stained by type II collagen antibody, and one out of 3 specimens of secondary ERMs had a minor component stained by type II collagen antibody. Compared with idiopathic ERMs with complete PVD, 2 out of 3 specimens of idiopathic ERMs with partial PVD or no PVD contained rather thick collagen lamellar., Conclusion: There was difference between specimens of idiopathic ERMs and specimens of secondary ERMs in staining by type II collagen antibody, supposed by vitreous, in this study. Idiopathic ERM with attached posterior vitreous membrane may cause growth of collagen.

Background: We encountered a patient with central retinal vein occlusion (CRVO) forming an epiretinal membrane (ERM) in a wide area. Generally formation of ERM is rare in CRVO., Patient and Methods: The patient was a 72-years-old female with ischemic CRVO in the right eye, who had undergone insufficient pan-retinal photocoagulation. Since ERM was formed in a wide area 7 months after the occurrence of CRVO, the patient underwent vitrectomy., Results: Although the patient was elderly, the posterior vitreum had not been detached, and ERM was observed in a wide area from the disk of the optic nerve over the vascular arcade. Since the ERM strongly adhered to the retina, incision of the membrane with vitreous scissors was required. The membrane tissue collected during the operation showed few vascular and cellular components, and consisted of ERM extracellular matrices such as collagen., Conclusions: In this patient, however, it was probable that not only barrier dysfunction of retinal vessel endothelial cells caused by elevated pressure in the retinal vein and rapid retinal ischemia but also the anatomical feature of the undetached posterior vitreum was involved in the formation of the ERM.