Eversão da cartilagem da terceira pálpebra em um gato / Eversion of the third eyelid cartilage in a cat

ABSTRACT

Background: Eversion of the cartilage of the third eyelid is a rare congenital disease in cats. It is caused by the anterioreversion of the cartilage edge of the third eyelid. Clinical signs may be associated with secondary keratoconjunctivitis,third eyelid gland protrusion, and ocular surface irritation. The diagnosis is made by ophthalmic examination, and treatment consists of surgical resection of the everted cartilage portion. The goal of the present study was to report a case ofeversion of third eyelid cartilage in a cat, given that it is an unusual abnormality in this animal species, and an importantdifferential diagnosis to be considered in the disorders of the third eyelid.Case A 6-year-old neutered female Persian cat was presented with a presumptive diagnosis of protrusion of the thirdeyelid gland, history of ocular irritation, and epiphora in the left eye. The disorder had been intermittently present sincethe animal was 1-year-old, with spontaneous disappearance after approximately 15 days. The owner related the reappearance of the disorder to stressful situations, with no previous history of trauma or other ocular alteration. During theophthalmic examination, suspended solute was observed through biomiscroscopic examination in both eyes, as well asan increase in volume of the third eyelid in the left eye, without other changes. A thorough examination, under generalanesthesia, indicated the protruding volume of the cartilage of the everted third eyelid. The third eyelid was pleated inits upper portion, demonstrating that the cartilage of the third eyelid was folded instead of following the curvature of theocular surface. Under general anesthesia, the cartilage was partially removed through two parallel incisions on the bulbarconjunctival surface, divulsioning 5 mm in length in the vertical portion of the cartilage in a ‘T’ shape, and separating the...