Vestibular neuronitis causes a self-limited episode of vertigo, presumably due to inflammation of the vestibular division of the 8th cranial nerve; some vestibular dysfunction may persist.
Sometimes vestibular neuronitis is used synonymously with viral labyrinthitis. However vestibular neuronitis manifests only with vertigo, whereas in viral labyrinthitis, tinnitus, hearing loss, or both are also present.
Although etiology is unclear, a viral cause is suspected. Vestibular neuronitis is usually unilateral.
Symptoms and Signs of Vestibular Neuronitis
Symptoms of vestibular neuronitis include a single attack of severe vertigo, with nausea and vomiting and persistent nystagmustoward the unaffected side, which lasts 7 to 10 days. The nystagmus is unidirectional, horizontal, and spontaneous, with fast-beat oscillations in the direction of the unaffected ear.
The absence of concomitant tinnitus or hearing loss is a hallmark of vestibular neuronitis and helps distinguish it from Meniere disease as well as labyrinthitis.
The condition slowly subsides over days to weeks after the initial episode. Some patients have residual dysequilibrium, especially with rapid head movements, probably due to permanent vestibular injury.
Diagnosis of Vestibular Neuronitis
Audiology, electronystagmography, and MRI
If clinicians suspect vestibular neuronitis, tests should include an audiologic assessment, electronystagmography with caloric testing, and gadolinium-enhanced MRI of the head, with attention to the internal auditory canals to exclude other diagnoses, such as cerebellopontine angle tumor, brain stem hemorrhage, or infarction. MRI may show enhancement of the vestibular nerves, consistent with inflammatory neuritis.
Treatment of Vestibular Neuronitis
Symptom relief with antiemetics, antihistamines, or benzodiazepines
Symptoms of vestibular neuronitis are symptomatically managed over the short term as in Meniere disease
Vestibular rehabilitation (usually given by a physical therapist) helps compensate for any residual vestibular deficit.
Key Points
Patients have severe, constant vertigo with nausea and vomiting and nystagmus toward the unaffected side; it lasts days to weeks.
Vestibular neuronitis does not cause hearing loss or tinnitus.
Do tests to exclude other disorders.
Treatment is directed at symptoms and includes antiemetics and antihistamines or benzodiazepines; corticosteroids may also be helpful.
