Contributors: Laurent Garosi, Rosanna Marsella
Species: Feline | Classification: Diseases
- Cause: disturbance of the central or peripheral vestibular system.
- May be secondary or idiopathic.
- Signs: ataxia, falling/rolling, leaning to one side, head tilt (unilateral) or wide excursion of the head from side to side (bilateral), circling, nystagmus.
- Diagnosis: signs.
- Treatment: depends on cause.
- Prognosis: reasonable to good, depending on cause.
Follow the diagnostic tree on Vestibular disease.
- Leaning to one side.
- Head tilt (unilateral vestibular).
- Wide excusion of the head from side to side (bilateral vestibular).
- Mean age for idiopathic disease is 4 years.
Central vestibular disease
- Menigoencephalitis Meningomyelitis: bacterial and fungal:
- Thiamine deficiency Thiamine deficiency.
- Cerebrovascular disease Cerebrovascular disease:
- Brain infarct.
- Brain hemorrhage Intracranial hemorrhage.
- Head trauma Head: trauma.
- Metronidazole toxicity Metronidazole.
Peripheral vestibular disease
- Otitis media Otitis media:
- Extension of otitis externa Otitis externa.
- Retrograde infection via eustachian tubes.
- Nasopharyngeal polyps Nasopharyngeal polyp.
- Congenital disease.
- Aminoglycoside antibiotics.
- Topical iodophors.
- Chlorhexidine Chlorhexidine.
- Fracture of temporal bone.
- Tympanic bulla damage.
- Acute onset over days.
- Signs may persist for weeks or months.
- Head tilt.
- Wide excursion of the head from side to side.
- Head tilt.
- Wide excursion of the head from side to side.
- Wide base stance.
- Head tilt (to side of lesion with unilateral vestibular disorder ), head tilt can be contralateral with lesion affecting the caudal cerebellar peduncle, fastigial nucleus and/or flocculonodular lobes of the cerebellum.
- Wide excursion of the head from side to side with bilateral peripheral or central vestibular disorder.
- Nystagmus (fast phase away from lesion):
- May be detected by clinical examination.
- May be detected by ophthalmoscopic examination only.
- May only be abnormal positional nystagmus.
- Vertical nystagmus and nystagmus that changes direction on changing position of the head can only be seen with central vestibular disorder.
- Leaning, rolling or falling to side of lesion.
- No postural weakness.
- Circling towards lesion.
- Mild hypertonia and hyperreflexia in limbs on side of lesion.
- Ventrally deviated eyeballs if head raised (strabismus).
- Horner's syndrome Horner's syndrome may be present with middle ear disease (tumor, otitis or polyps).
- Signs associated with central lesion, eg abnormal mentation, UMN hemiparesis, general or reduced proprioceptive ataxia, deficits of cranial nerves V to XII (other than VII and VIII).
- Skull radiography Radiography: skull (basic) may be useful in demonstrating otitis media or nasopharyngeal polyps .
- Imaging techniques:
- Otoscopic and pharyngeal examination under general anesthesia:
- Otitis externa Otitis externa with extension by rupture of tympanic membrane.
- Tympanic membrane may appear discolored by fluid in middle ear.
- Myringotomy Myringotomy with a 20-gauge spinal needle to obtain samples for cytology and culture if the tympanic membrane is intact, but bulging or of an abnormal color.
- Swabs for cytology and culture (aerobic, fungal and yeast) from the middle ear if the tympanic membrane is ruptured.
- CSF analysis Cerebrospinal fluid: sampling (nucleated cell count Cerebrospinal fluid: cell count and differential, cytology Cerebrospinal fluid: cytology, total protein concentration, PCR for infectious titer PCR (Polymerase chain reaction)).
- Otitis media without vestibular involvement.
Initial Symptomatic Treatment
- Depends on cause
- No evidence to suggest that any treatment affects outcome of disease.
- Meclizine (6.25 mg PO q12h) and/or diazepam Diazepam (1-2 mg PO q8h) are sometimes helpful in decreasing signs associated with acute vestibular disorder (nausea, anorexia, anxiety, and, in some instances, the severity of the head tilt and ataxia).
- Myringotomy Myringotomy (puncture of tympanic membrane (if intact) to relieve pressure and obtain fluid sample for diagnosis).
- Performed under general anesthesia.
- Clean external ear canal and then puncture tympanic membrane in ventrocaudal aspect with 22 guage spinal needle.
- Aspirate fluid sample and flush gently with 0.2-0.4 ml sterile saline.
- Treat with broad spectrum systemic antibiotics Therapeutics: antimicrobial drug for a minimum of 4-6 weeks. Choice of antibiotic is dictated by results of culture/sensitivity if available; if not amoxicillin/clavulanate Amoxicillin Clavulanate, cephalosporine or fluoroquinone are reasonable choices to consider.
Delay topical therapy for 4-5 days if myringotomy performed.
- Surgical drainage and debridement via bulla osteotomy Bulla osteotomy if refractory to medical treatment.
- Polyp should be removed Nasopharyngeal polyp removal.
- Good to reasonable depending on cause.
- Most idiopathic cases improve over several days and may continue to improve for up to 8 weeks.
- Good prognosis if underlying disease identified and treated eg otitis media, or nasopharyngeal polyp.
- Congenital cases may stabilize and occasionally signs regress then recur.
Expected Response to Treatment
- Resolution of nystagmus over days to weeks. Reducing ataxia and head tilt.
Many animals with on-going disease learn to accommodate and clinical signs may reduce with time.
Reasons for Treatment Failure
- Underlying condition not diagnosed or treated adequately.
- Recent references from PubMed and VetMedResource.
- Negrin A, Cherubini G B, Lamb C et al (2010) Clinical signs, magnetic resonance imaging findings and outcome in 77 cats with vestibular disease: a retrospective study. J Feline Med Surg 12 (4), 291-299 PubMed.
- Rossmeisl J H Jr. (2010) Vestibular disease in dogs and cats. Vet Clin North Am Small Anim Pract 40 (1), 81-100 PubMed.
- Thomas W B (2000) Vestibular dysfunction. Vet Clin North Am Small Anim Pract 30 (1), 227-249 PubMed.
- LeCouteur R A & Vernau K M (1999) Feline vestibular disorders Part 1 - anatomy and clinical signs. J Feline Med Surg 1 (2), 71-80 PubMed.
- Vernau K M & LeCouteur R A (1999) Feline vestibular disorders Part 2 - diagnostic approach and differential diagnosis. J Feline Med Surg 1 (2), 81-8 PubMed.
- Schunk K L (1988) Disorders of the vestibular system. Vet Clin North Am 18 (3), 641-665 VetMedResource.
- Burke E E, Moise N S, de Lahunta A (1985) Review of idiopathic feline vestibular syndrome in 75 cats. JAVMA 187 (9), 941-3 PubMed.
Other sources of information
- de Lahunta A, Glass E (2009) Vestibular system - special proprioception. Veterinary Neuroanatomy and Clinical Neurology. 3rd edn. W B Saunders, Elsevier, St Louis, Missouri, pp 319-347.
- Munana K R (2004) Head tilt and nystagmus. In: BSAVA Manual of Canine and Feline Neurology. 3rd edn. S R Platt & N J Olby eds. BSAVA, pp 155-171.