Is Idiopathic Intracranial Hypertension (IIH) or vestibular migraine more likely to cause hearing loss and ear pressure?

IIH is More Likely to Cause Hearing Loss and Ear Pressure Than Vestibular Migraine

Idiopathic intracranial hypertension (IIH) is significantly more likely to cause both hearing loss and ear pressure compared to vestibular migraine, with these symptoms directly related to elevated intracranial pressure being transmitted to the inner ear. 1, 2

Key Distinguishing Features

IIH Otologic Manifestations

IIH commonly presents with ear-related symptoms that are mechanistically linked to elevated intracranial pressure:

• Pulsatile tinnitus is a hallmark symptom of IIH and represents an important diagnostic clue, particularly when low-pitched 1, 3
• Aural fullness/ear pressure occurs in approximately 61% of IIH patients and improves after lumbar puncture when intracranial pressure is normalized 2
• Hearing loss can develop in IIH, especially with long disease duration or when associated ear pathologies are present (dehiscence, fistula, hypermobile footplate, or chronic ear infections) 1, 4
• Tinnitus is present in approximately 68% of IIH patients, and this symptom is even listed as a common side effect of acetazolamide treatment, suggesting the baseline prevalence is substantial 5, 2

Evidence of Pressure Transmission to Inner Ear

The mechanism by which IIH causes these symptoms is well-established:

• Elevated intracranial pressure is directly transmitted to the inner ear structures 2
• Endolymphatic hydrops (ELH) symptoms—including tinnitus (67.7%), dizziness (77.4%), vertigo (22.6%), and aural fullness (61.3%)—significantly improve after lumbar puncture normalizes intracranial pressure 2
• Pure-tone audiometry thresholds objectively improve after LP-induced pressure normalization, confirming the causal relationship 2

Vestibular Migraine Characteristics

Vestibular migraine typically does NOT cause hearing loss or ear pressure:

• In most vestibular migraine cases, hearing is normal 1
• The primary symptoms are episodic vertigo, dizziness, and head fullness-pressure, but these are not accompanied by the pulsatile tinnitus or aural pressure characteristic of IIH 1
• Imaging findings help differentiate: IIH shows decreased pituitary height, optic nerve sheath distention, flattened posterior globe, and bilateral transverse sinus stenosis—features absent in migraine 6

Clinical Algorithm for Differentiation

When evaluating a patient with ear pressure and hearing symptoms:

1. Ask specifically about pulsatile tinnitus (low-pitched, rhythmic with heartbeat)—this strongly suggests IIH over vestibular migraine 1, 3

2. Assess for other IIH features:

   • Transient visual obscurations
   • Radicular neck pain
   • Daily headache pattern (93.5% of IIH patients have chronic headache) 3, 2

3. Perform audiometry: Hearing loss or threshold changes favor IIH, while normal hearing favors vestibular migraine 1, 2

4. Consider neuroimaging: MRI/MRV showing empty sella, optic nerve sheath distention, posterior globe flattening, or venous sinus stenosis confirms IIH 1, 6

Critical Clinical Pitfall

The most important pitfall is misdiagnosing IIH as vestibular migraine when patients present with head fullness-pressure and dizziness. Many IIH patients are initially given a clinical diagnosis of vestibular migraine because these symptoms overlap considerably 1. However, the presence of pulsatile tinnitus, aural fullness that improves with pressure reduction, or any degree of hearing impairment should prompt investigation for elevated intracranial pressure rather than accepting a vestibular migraine diagnosis 1, 2.