Page 843 - Problem-Based Feline Medicine

38. The cat with a head tilt, vestibular

ataxia or nystagmus

Joane M Parent

KEY SIGNS
● Cat leans, drifts, falls or rolls to the side of the head tilt.
● Rapid eyeball movement, either horizontally, vertically or rotatory.
● Reluctance to walk, crouched stance, exaggerated swaying of head, poor to
absent normal nystagmus.

MECHANISM?
● Any disease affecting the vestibular system, peripherally or centrally, results in a head tilt that
may or may not be associated with vestibular ataxia and nystagmus.
● Pendular (described as oscillatory) nystagmus is not vestibular in origin. It is the result of a
defect in the visual pathways. It is always congenital.
WHERE?
● The vestibular system is affected either peripherally, in the inner ear within the petrosal bone,
or centrally, within the cranial vault, in the brainstem, at the level of the rostral medulla.
WHAT?
● The diseases of the peripheral vestibular apparatus are the most common. They include idio-
pathic vestibular disease and otitis media-interna.
● Involvement of the central vestibular system occurs less frequently. The meningoen-
cephalomyelitides, including principally feline infectious peritonitis and fungal conditions, are
the most common causes.

QUICK REFERENCE SUMMARY
Diseases causing head tilt, vestibular ataxia or nystagmus

ANOMALY
● Congenital vestibular disease (p 848)
Varying degrees of head tilt, falling and rolling are present from birth. Reported in Siamese and
Burmese kittens.

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