Association of incidental epithelialization of corneal endothelium with endothelial barrier impairment

Purpose To identify patients with incidental epithelialization of corneal endothelium (IECE) detected in in vivo confocal microscopy (IVCM) and analyze its association with corneal decompensation. Methods We performed a retrospective analysis of IVCM (Rostock Cornea Module, HRT III) scans of 327 patients treated in outpatients clinic for various corneal diseases. After identification of cases with IECE, visual acuity (VA), central corneal thickness (CCT) data, endothelial cell density, as well as slit‐lamp photographs were collected. CCT measurements were obtained using Pentacam (Oculus). Results From among of 327 IVCM examinations, IECE was visible in 8 patients associated with Posterior Polymorphous Corneal Dystrophy (PPCD) in 3 out of 6 patients with an IVCM diagnosis of PPCD; Fuch's Endothelial Dystrophy (FED) in 3 out of 12 FED patients with available IVCM scans. One patient was diagnosed with unilateral IECE after the incident of facial UV‐light burn (tanning salon) with the unilateral mild burn of the ocular surface. One patient presented unilateral IECE in superior half of the cornea due to epithelial ingrowth after cataract surgery. PPCD patients with presence of IECE developed corneal edema and greater endothelial cell loss, in contrast to age‐matching PPCD patients without IECE. Patients with FCD or cornea guttata developed corneal decompensation and visual impairment at the earlier age (before 50 y.o.) than FCD patients without IECE. Advanced IECE observed in the patient with ingrowth syndrome, as well as epithelial metaplasia after UV‐light burn resulted in severe visual impairment. Conclusions Diagnosis of corneal diseases should be supplemented by IVCM examination. IECE observed in IVCM could be considered as a prognosis factor of visual impairment in corneal endothelial diseases, however it requires more research.