Classification of corneal endothelial disorders based on neural crest origin.

The corneal endothelium is derived from the neural crest. A general classification of disorders of development of the neural crest has been previously presented (Johnston). Disorders of the corneal endothelium may be considered according to a modification of this scheme to reflect its true embryologic origin. In this classification, corneal endothelial disorders are categorized as abnormalities of neural crest cell formation (cyclopia), migration (Peters' anomaly), proliferation (iridocorneal endothelial syndrome), final differentiation (Fuchs' dystrophy), and acquired abnormalities (metaplasia, abiatrophy, and proliferation).