Corneal endothelial degeneration and fibrous proliferation after plana vitrectomy.

A 45-year-old woman with juvenile-onset diabetes had persistent corneal edema after a pars plana vitrectomy and lensectomy procedure. Phase contrast and electron microscopic observation of the patient's cornea revealed extreme attenuation of the endothelial cell layer and abnormal collagenous and basement membrane material interposed between Descemet's membrane and the endothelium. Endothelial fibrous proliferations in this case were consistent with the development of ultrastructurally identical fibrous proliferations in many other situations involving dysfunction of the corneal endothelium.