Phenotypic Heterogeneity of Corneal Endothelium in Iridocorneal Endothelial Syndrome by In Vivo Confocal Microscopy

Purpose: To present a case of iridocorneal endothelial (ICE) syndrome showing phenotypic heterogeneity of endothelial morphology between the 2 eyes of a patient as visualized by in vivo confocal microscopy (IVCM). Methods: Confocal microscopy using the Heidelberg Retina Tomograph (HRT)-3 with Rostock Cornea Module was performed bilaterally during routine follow-up on a 60-year-old lady being managed as a case of ICE syndrome with secondary glaucoma in the right eye. Results: IVCM revealed endothelial changes in both eyes, which however varied in morphology. Endothelium of the right eye showed a "total ICE" pattern with "ICE-type of cells," that is, diffuse involvement with enlarged, pleomorphic "epithelioid" cells having hyper-reflective nuclei and no intervening areas of the normal endothelium. The left endothelium had broad areas of normal hexagonal endothelial mosaic interspersed with different types of ICE cells showing nipple-shaped evaginations, light dark reversal and central craters with hyper-reflective rims. Conclusions: This report with the help of IVCM demonstrates that though ICE syndrome is a clinical entity which classically has been considered predominantly unilateral, the endothelial changes can be bilateral and heterogeneous. The apparent heterogeneity in the present case may represent 2 different stages of the disease process at the level of the corneal endothelium-advanced disease OD and presymptomatic disease OS.