Tessier Clefts and Hypertelorism.

Tessier's classification system for rare craniofacial clefts remains the most widely used today. It denotes the position of the cleft process in a schema based around the orbit, and facilitates communication between surgeons regarding these complicated conditions. Tessier's classification is reviewed in detail, and a separate discussion of hypertelorism (increased distance between the bony orbits) follows, focusing on orbital hypertelorism in the setting of craniofacial clefts.