Ultrastructural and immunohistochemical findings in five patients with vitreomacular traction syndrome

Objective: To evaluate pathologic features of vitreomacular traction syndro me (VMT). Methods: Preretinal membranes removed from five patients during Vitreous su rgery for VMT syndrome were evaluated by electron microscopy (n = 4) and im munohistochemistry (n = 1). Results: Electron microscopic examination revealed large segments of intern al limiting lamina (ILL) in three of the four cases. Other extracellular fe atures included two types of abnormal collagen fibrils, determined to be ty pe I and fibrous long-spacing collagen. The myofibrocyte was the predominan t cell type in all cases. Collagen types I, II, and Ill, as well as glial f ibrillary acidic protein and vimentin, were identified by immunohistochemis try. Conclusions: Epiretinal membranes in eyes with VMT syndrome adhered tightly to the ILL with abnormal collagen and contractile elements that included m yofibrocytes.