Diseases of the corneal endothelium

Abstract

The corneal endothelial monolayer and associated Descemet's membrane (DM) complex is a unique structure that plays an essential role in corneal function. Endothelial cells are neural crest derived cells that rest on a special extracellular matrix and play a major role in maintaining stromal hydration within a narrow physiologic range necessary for clear vision. A number of diseases affect the endothelial cells and DM complex and can impair corneal function and vision. This review addresses different human corneal endothelial diseases characterized by loss of endothelial function including: Fuchs endothelial corneal dystrophy (FECD), posterior polymorphous corneal dystrophy (PPCD), congenital hereditary endothelial dystrophy (CHED), bullous keratopathy, iridocorneal endothelial (ICE) syndrome, post-traumatic fibrous downgrowth, glaucoma and diabetes mellitus.

Keywords: Edema; Endothelial disease; Fibrosis; Fuchs corneal endothelial dystrophy; Stroma.

Figure 1.

A) Clinical appearance of FECD cornea with edema and areas of fibrosis in subepithelial area impairing vision. B) Endothelial cells decreased in number and presence of guttae is seen in this specular microscopy photograph, does not correspond to Figs. 1A and 1C. C) Anterior segment imaging using Optical Coherence Tomography shows corneal edema and areas of fibrosis, shown by arrows.

Figure 2.

A) Posterior polymorphous dystrophy with dense collection of endothelial cells resting on DM of increased thickness. No evidence of stratification is seen in this section (Periodic acid-Schiff stain [PAS]; bar = 15 microns). B) Iridocorneal endothelial syndrome of the Cogan-Reese type with pseudo-angle covered by basement membrane which extends on to iris surface where it becomes multilayered and entwined with a nodule of melanocytes (PAS; bar = 15 microns).