Entropion may involve different segments of the eye lid. The
in-rolling of the eye lid causes constant irritation, tearing,
squinting and discomfort due to irritation of the cornea by the hair
of the inverted eye lid. Pussy eye discharge, corneal ulceration,
darkening and rupture are seen in more severe cases.
The condition is common in brachycephalic (flat face) breeds such as Persian cats, bulldogs, pugs, shar peys, toy breeds (poodle and Yorkshire terrier), and giant breeds (Mastiff, St. Bernard, and Newfoundland). Entropion is usually diagnosed at an early age. In some instances, Entropion can be secondary to continuous squinting (blepharospasm) due to chronic irritation, inflammation and other primary conditions.
Ectropion is rare in cats, but fairly common in dogs. Sporting
breeds (spaniels, hounds, and retrievers), giant breeds and any
breed with loose facial skin (especially bloodhounds) are
predisposed to the condition.
The eversion of the eye lid exposes the eye to air, outside
irritants and infections. Tearing, facial staining, thick discharge
and eye globe damage are common signs. Other diseases may cause
functional entropion and can be diagnosed by additional testing.
Primary entropion and ectropion are treated by corrective surgery that re-modulates the shape of the eye lid.