Causes of Vestibular Neuritis
Vestibular neuritis is most commonly caused by viral infections, particularly herpes simplex virus reactivation, that affect the vestibular nerve, vestibular ganglion, or labyrinth. 1
Primary Causes
Viral Infections
- Herpes simplex virus (HSV): The predominant theory is that vestibular neuritis results from reactivation of latent HSV in the vestibular ganglion 2
- Other viral agents implicated include:
- Mumps virus
- Rubella virus
- Cytomegalovirus
- Epstein-Barr virus
- Enteroviruses 3
Inflammatory Response
- Histopathological studies show degeneration of the superior vestibular nerve 1
- Recent evidence indicates neuroinflammation of the vestibular nerve with gadolinium enhancement visible on MRI during acute phases 4
Secondary Contributing Factors
Vascular Mechanisms
- Vascular occlusion has been proposed as a potential mechanism 1
- Ischemia of the vestibular nerve or labyrinth may contribute to the pathology
Immunological Factors
- Immune-mediated mechanisms have been suggested 1
- The condition may represent an immune-related vestibular neuropathy
Clinical Presentation and Differentiation
Vestibular neuritis presents with:
- Sudden onset of severe vertigo
- Prolonged symptoms lasting days to weeks
- Nausea and vomiting
- Imbalance
- No hearing loss (distinguishing it from labyrinthitis) 5
- No other neurological symptoms (distinguishing it from central causes) 5
Important Diagnostic Considerations
Ruling Out Central Causes
- Critical to differentiate from brainstem or cerebellar stroke, which can be life-threatening 2
- HINTS examination (Head Impulse, Nystagmus, Test of Skew) can help differentiate peripheral from central causes 5
- Patients with vascular risk factors should be evaluated for possible stroke 2
Imaging Findings
- MRI may show decreased caliber of the vestibular nerve
- Enhancement of the vestibular nerve may be visible following IV gadolinium administration 5
- Routine MRI is often normal in vestibular neuritis 5
Long-Term Outcomes
Prognosis depends less on peripheral vestibular damage and more on:
- Visual dependence factors
- Psychological traits (anxiety, somatization)
- Central compensation mechanisms 4
Clinical Pearls and Pitfalls
- Pitfall: Misdiagnosing central vertigo (stroke) as vestibular neuritis - always consider vascular causes in patients with risk factors
- Pitfall: Prolonged use of vestibular suppressants may impede central compensation 2
- Pearl: Early resumption of normal activity promotes compensation and recovery 2
- Pearl: Directed vestibular rehabilitation therapy can accelerate recovery in patients with poor compensation 6
Vestibular neuritis is the second most common cause of peripheral vestibular vertigo and represents a significant cause of acute vertigo presentations. While viral etiology (particularly HSV) is the leading theory, the exact pathophysiological mechanisms remain incompletely understood.