Vestibular disorders are common in cats. The vestibular apparatus (called the labyrinth) is a complex sense organ composed of three semicircular canals, plus the utricle and the saccule. The labyrinth is stimulated by gravity and rotational movements. It plays an important role in balance and orienting the body in space. Inflammation of the labyrinth is called labyrinthitis.
A cat with labyrinthitis has a problem with balance. The animal wobbles, circles, falls and rolls over, and has trouble righting herself. She may lean against the wall for support and crouch low to the floor when walking. The cat often shows rapid jerking eye movements (nystagmus), and her head will usually tilt down on one side. When picked up and turned in a circle, the cat will act even more dizzy. There may be vomiting and deafness.
There are several types of ear mites that can live in cats’ ears, but the most common are Otodectes cynotis, tiny, eight-legged parasites that feed on the wax and oils in a cat’s ear canal. An individual mite has an approximately three-week life cycle, and is barely detectable by the naked eye. Causing irritation and inflammation, ear mites can infect the external and internal canal, and lead to more serious skin or ear infections if left untreated. Infection usually produces a characteristic...
A common cause of labyrinthitis is inner ear infection. Other causes include stroke, brain tumor, head trauma, brain infection, drug intoxication (especially by the aminoglycoside antibiotics), and thiamin deficiency.
A congenital vestibular defect is seen in Oriental breeds. Kittens show a head tilt, circling, and rolling behaviors. Siamese kittens with this condition may also be deaf. There is no cure.
Idiopathic vestibular syndrome is the most common cause of labyrinthitis in cats. The onset is sudden and the cause is unknown. The signs include a head tilt and nystagmus, and cats may have difficulty walking. There is an increase in these cases in July and August in the northeastern United States, suggesting an environmental cause.
Treatment: With cases of idiopathic vestibular syndrome, in two to three days, the cat begins to recover on her own. In most cases, the cat is well in three weeks, although some cats retain a permanent head tilt. During the recovery period, the cat will need supportive care.
WebMD Veterinary Reference from "Cat Owner's Home Veterinary Handbook"