Definition: Inflammation of the vestibular portion of the eighth cranial nerve, presenting with vertigo, nausea, and gait imbalance.
Nature: Benign, self-limited condition lasting several days; complete resolution of symptoms can take weeks to months.
Diagnosis: Clinical, requiring differentiation from central causes like cerebrovascular syndromes.
Treatment: Supportive, including antiemetics, antihistamines, and benzodiazepines; vestibular rehabilitation after nausea/vomiting control.
Introduction
Cause: Believed to be associated with viral infection, causing inflammation of the vestibular portion of the eighth cranial nerve.
Presentation: Acute onset of vertigo, nausea, vomiting, and gait imbalance.
Prognosis: Typically resolves without intervention; vestibular symptoms can persist for weeks to months.
Etiology
Presumed Cause: Viral origin (e.g., reactivation of latent HSV infection).
Other Theories: Vascular etiology and immunologic factors.
Epidemiology
Incidence: Third most common cause of peripheral vertigo after BPPV and Meniere disease.
Prevalence: Diagnosed in 6% of patients presenting with dizziness in emergency departments in the USA.
Demographics: No gender preference; commonly affects middle-aged individuals.
Pathophysiology
Mechanism: Inflammation affecting the superior division of the vestibular nerve more than the inferior division.
Histologic Findings: Vestibular damage with predilection for the superior vestibular labyrinth.
History and Physical Examination
Symptoms:
Vertigo: Constant, worsened with head movement.
Nausea/Vomiting: Common.
Balance Problems: Acute onset, peaks within 24-48 hours.
Preceding Viral Illness: Noted in up to 50% of patients.
Differential Symptoms: Absence of headaches; accompanying symptoms (visual changes, somatosensory changes, weakness, dysarthria, incoordination) may indicate central causes.
Physical Exam:
Normal Neurological Exam: Peripheral vertigo findings include a negative HINTS exam.
HINTS Exam: High sensitivity and specificity for distinguishing peripheral from central vertigo.
Components of HINTS Exam:
Head Impulse Test: Positive test indicates peripheral etiology.
Nystagmus: Horizontal or horizontal-torsional, unidirectional indicates peripheral cause.
Test of Skew: No eye deviation indicates peripheral cause.
Evaluation
Diagnosis: Based on clinical signs and symptoms.
Imaging: MRI preferred over CT if central causes need to be ruled out; not typically indicated unless symptoms persist or risk factors for stroke exist.
Additional Tests: Cervical and ocular vestibular evoked myogenic potentials, video head impulse testing.
Treatment / Management
Symptomatic Treatment:
Antiemetics: Promethazine 12.5-25 mg every 4-6 hours, Metoclopramide 10 mg three times daily.
Antihistamines: Diphenhydramine 25-50 mg every 4-6 hours, Meclizine 25-50 mg up to three times daily.
Benzodiazepines: Diazepam 2-5 mg three times daily, Lorazepam 0.5-1 mg three times daily (use for no more than 3 days)..
Duration: Use for no more than three days to avoid delaying central compensation.
Vestibular Rehabilitation: Recommended after acute symptoms are controlled.
Corticosteroids: Efficacy controversial; insufficient evidence to recommend.
Antiviral Medications: Valacyclovir not shown to be effective.
Differential Diagnosis
Peripheral Causes:
Benign Paroxysmal Positional Vertigo (BPPV): Episodic vertigo with head movements.
Meniere Disease: Recurrent episodes with sensory symptoms (ear fullness, tinnitus).
Labyrinthitis: Similar to vestibular neuritis but includes unilateral hearing loss.
Central Causes:
Vestibular Migraine: Central/peripheral signs, recurrent episodes, associated with migraine.
Vertebrobasilar TIA: Vascular risk factors, acute onset, short duration.
Brainstem Ischemia/Infarct: Acute onset, neurological symptoms, history of trauma.
Outcome: Typically uncomplicated with complete resolution in most cases.
Persistent Symptoms: 15% with symptoms at one year.
Recurrence: Infrequent (2-11% of patients).
Complications
Benign Paroxysmal Positional Vertigo (BPPV): Develops in 10-15% of patients within weeks.
Persistent Postural-Perceptual Dizziness (PPPD): Non-spinning vertigo, unsteadiness, found in 25% of patients followed 3-12 months after acute vestibular disorders.
Deterrence and Patient Education
Acute Onset of Persistent Vertigo: Suggests vestibular neuritis.
Consultation: Seek consultation with primary care, emergency, or ENT physician.
Primary Evaluation: Exclude severe brain or vascular diseases, refer to ENT for further testing.
Enhancing Healthcare Team Outcomes
Interprofessional Approach:
Role of Pharmacists: Medication reconciliation, verify dosing, counsel on administration and adverse effects.
Role of Nurses: Monitor treatment progress, answer patient questions, report concerns to clinicians.
Vestibular Rehabilitation: Early improvement through individually designed programs.
Collaborative Effort: Essential for optimal patient care, especially in distinguishing vestibular neuritis from central causes like cerebrovascular events.