Peripheral Pathologies of Dizziness
The most common peripheral pathologies causing dizziness are Benign Paroxysmal Positional Vertigo (BPPV), vestibular neuritis, Menière's disease, and labyrinthitis, with BPPV accounting for 42% of vertigo cases in non-specialty settings. 1
Major Peripheral Vestibular Disorders
Benign Paroxysmal Positional Vertigo (BPPV)
- Characterized by brief episodes of vertigo triggered by position changes
- Most common peripheral cause of vertigo in primary care
- Diagnostic features:
- Positive Dix-Hallpike test (key diagnostic maneuver)
- Rotational nystagmus with characteristic latency and fatigue
- Brief duration of symptoms (seconds to minutes)
- Treatment: Canalith Repositioning Procedure (Epley maneuver) with 80% success rate 2
Vestibular Neuritis
- Presents with sudden, severe vertigo lasting days
- Diagnostic features:
- Unidirectional horizontal nystagmus
- Normal HINTS examination (Head Impulse, Nystagmus, Test of Skew)
- No hearing loss
- Treatment: Early corticosteroid therapy may improve outcomes 2
Menière's Disease
- Episodic vertigo with characteristic associated symptoms
- Diagnostic features:
- Fluctuating hearing loss
- Tinnitus
- Aural fullness
- Episodes typically last hours
- Treatment: Lifestyle modifications, diuretics, intratympanic dexamethasone or gentamicin in severe cases 2
Labyrinthitis
- Similar to vestibular neuritis but with associated hearing loss
- Caused by inflammation of both vestibular and cochlear portions of labyrinth
- Often viral in origin
- Treatment: Symptomatic management, possible short-term vestibular suppressants
Prevalence and Distribution
In non-specialty clinical settings, the distribution of peripheral vestibular disorders is:
- BPPV: 42% of vertigo cases
- Vestibular neuritis: 41%
- Menière's disease: 10%
- Other causes: 7% 1
In subspecialty settings, the distribution shifts to:
- Menière's disease: 43%
- BPPV: 23%
- Vestibular neuritis: 26%
- Other causes: 8% 1
Distinguishing Features of Peripheral vs. Central Vertigo
Peripheral vertigo (vestibular) typically presents with:
- Intense rotational sensation
- Nausea and vomiting
- Horizontal or rotatory nystagmus that suppresses with visual fixation
- No neurological deficits
- Symptoms improve with time due to central compensation 2
Central causes of vertigo (which must be ruled out) often present with:
- Down-beating nystagmus on Dix-Hallpike maneuver
- Direction-changing nystagmus without head position changes
- Baseline nystagmus without provocative maneuvers
- Associated neurological symptoms
- Nystagmus that doesn't fatigue or suppress with fixation 1
Clinical Approach to Peripheral Dizziness
The most effective diagnostic approach focuses on timing and triggers rather than symptom quality:
- Acute vestibular syndrome: Sudden, continuous vertigo lasting days
- Spontaneous episodic vestibular syndrome: Recurrent, unprovoked episodes
- Triggered episodic vestibular syndrome: Brief episodes with specific triggers 2
Common Pitfalls in Diagnosis
- Failing to perform the Dix-Hallpike maneuver in patients with positional symptoms
- Routinely prescribing vestibular suppressants for BPPV (can delay central compensation)
- Missing central causes by not performing the HINTS examination when indicated
- Ordering unnecessary imaging for clear peripheral vertigo 2
Special Considerations
- Posttraumatic vertigo can present with various manifestations including BPPV
- Multiple vestibular disorders may coexist (e.g., BPPV following vestibular neuritis)
- Failure to respond to appropriate treatment should raise concern for misdiagnosis
- Orthostatic hypotension is a common non-vestibular cause of dizziness, especially in elderly patients 1, 2
Proper identification of peripheral vestibular disorders is crucial for appropriate management and to avoid unnecessary testing while ensuring serious central causes are not missed.