Corneal keloid.

Reports of corneal keloids are rare, with fewer than 80 cases published since the first case was documented in 1865. Keloids can be congenital or primary, but most often are associated with ocular surface injury or pathology. They have been reported in association with a number of congenital conditions, notably lowe's syndrome. Keloids are characterized histopathologically by a haphazard arrangement of fibroblasts, collagen bundles, and blood vessels. They have sometimes been confused with hypertrophic scars, but differ from such scars in that they may appear months or years after initial trauma and enlarge over time. The underlying cornea may be clear and uninvolved, or it may be opaque, depending on the primary pathology of the keloid. Treatment options include superficial keratectomy, lamellar or penetrating keratoplasty, and sclerokeratoplasty. The purpose of this review is to tabulate features of the reported corneal keloids, describing their etiologic, clinical, and histopathologic characteristics and discussing possible mechanisms of keloid formation.