Contributor: Gordon K. Klintworth
Bullous keratopathy is a common keratopathy develops secondary to corneal endothelial dysfunction in which the corneal stroma and corneal epithelium become edematous and bullae form between the corneal epithelium and Bowman layer. Bullous keratopathy can result from different conditions that cause a loss of the corneal endothelium. This includes cataract extraction, intraocular lens implantation, immunologic mechanisms in corneal graft rejection, donor tissue for penetrating keratoplasty that has a defective corneal endothelium, chronic glaucoma [glaucoma - chronic], and the introduction of toxic substances into the anterior chamber . The types of bullous keratopathy include aphakic bullous keratopathy [bullous keratopathy - aphakic], pseudophakic bullous keratopathy [bullous keratopathy - pseudophakic], and Fuchs corneal dystrophy. The condition causes decreased visual acuity. Surgically excised corneal tissues have epithelial edema, intraepithelial vesicles, subepithelial bullae between the corneal epithelium and Bowman layer, a mild degenerative pannus, and markedly fewer than normal corneal endothelial cells are features. Ectopic intraepithelial basement membrane may be present. Mild degrees of stromal edema are difficult to discern histologically, but the edematous corneal stroma may be thickened and resemble "cotton-candy" in appearance. The commonly observed artifactual clefts between the collagen lamellae are diminished or absent.