PATHOLOGY OF THE IRIDOCORNEAL-ENDOTHELIAL SYNDROME - THE ICE-CELL

Purpose, The iridocorneal-endothelial (ICE) syndrome is characterized by glaucoma, corneal failure, and iris destruction. Specular photomicr oscopy of the corneal endothelium in this disease shows a population o f abnormal cells named ICE-cells. Comparison between ultrastructural e xamination and specular photomicroscopy demonstrates that the histolog ic equivalent of ICE-cells are cells with an epithelial phenotype, The authors have studied the differentiation markers expressed by ICE-cel ls using an ultrastructural immunocytochemical technique. Methods, Sev en keratoplasty specimens from patients with the ICE syndrome were exa mined by scanning and transmission electron microscopy and light and e lectron microscopic immunocytochemistry. Comparison was made with thre e normal corneas. Immunocytochemical studies were performed with monoc lonal antibodies to broad-spectrum cytokeratins, cytokeratins 3, 5/8, 8/18 and 19, vimentin, and epithelial membrane antigen. Results, ICE-c ells were morphologically similar to epithelial cells and expressed th e same profile of differentiation markers as did normal limbal epithel ial cells. Conclusions, ICE-cells may arise from an embryologic ectopi a of ocular surface epithelium. Alternatively, these findings are cons istent with a metaplastic stimulus resulting in a profound change in t he phenotype of normal corneal endothelial cells.