Contributor: Gordon K. Klintworth
Atresia of the nasolacrimal duct is a fairly common developmental disorder of the lacrimal drainage system that most often affects the lacrimal ostium. It usually results from a non-canalization of the nasolacrimal duct. It may be indistinguishable from an obstruction to the nasolacrimal duct by cellular debris or external compression caused by bone. The latter may be associated with defomed face. Some cases are inherited.