Is an electroencephalogram (EEG) indicated in a patient presenting with dizziness, vertigo, and headache for four days?

EEG is Not Indicated for Dizziness and Vertigo with Headache

EEG is not recommended for patients presenting with dizziness, vertigo, and headache for four days, as it has limited utility in unselected patients with these symptoms. 1

Appropriate Diagnostic Approach

The diagnostic approach for dizziness, vertigo, and headache should focus on:

1. Clinical Evaluation

   • Focus on timing, triggers, and associated symptoms rather than quality of dizziness 1
   • Assess for red flags including:
     • Sudden severe headache
     • New neurological symptoms
     • Inability to walk or stand
     • Persistent vomiting
     • Altered mental status 1

2. Vestibular Examination

   • A thorough vestibular examination should be performed before considering any advanced testing 1
   • Key tests include:
     • HINTS examination (Head Impulse, Nystagmus, Test of Skew)
     • Dix-Hallpike maneuver for posterior canal BPPV
     • Supine roll test for lateral canal BPPV 1

3. Consider Vestibular Migraine

   • Vestibular migraine is the most common cause of spontaneous recurrent episodic vertigo, accounting for approximately 10% of patients with vertigo and dizziness 2
   • It presents with variable duration of symptoms and may occur without headache in about one-third of patients 2
   • Women are significantly more affected than men 2

When to Consider Imaging

MRI brain (without contrast) is preferred when central causes are suspected, particularly in:

• Acute Vestibular Syndrome with abnormal HINTS examination
• Patients with neurological deficits
• High vascular risk patients even with normal examination
• Chronic undiagnosed dizziness not responding to treatment 1

Why EEG is Not Indicated

1. According to European Heart Journal guidelines, EEG has limited utility in unselected patients with dizziness or syncope 1
2. No specific EEG findings exist for any loss of consciousness other than epilepsy 1
3. Epileptic vertigo or dizziness (EVD) is rare, particularly when vestibular symptoms are the sole manifestation (isolated EVD present in only 0.8% of cases) 3

Exception: When to Consider EEG

EEG might be considered only if:

• There is clinical suspicion of epilepsy with specific features suggesting seizures
• Vestibular symptoms are accompanied by altered consciousness, automatisms, or other epileptic features
• Episodes are very brief (<30 seconds) and stereotyped, which is characteristic of isolated epileptic vertigo (69.6% of cases) 3

Most Likely Diagnosis to Consider

Given the presentation of dizziness, vertigo, and headache for four days, vestibular migraine should be high on the differential diagnosis:

• It is now recognized as the most common cause of spontaneous episodic vertigo 4
• Attacks may last from seconds to days 2
• Presents with considerable clinical variation 2
• Often coexists with or mimics other vestibular disorders like BPPV or Menière's disease 4

Recommended Diagnostic Tests

Instead of EEG, the following tests should be prioritized:

• Thorough neurological and vestibular examination including HINTS
• Dix-Hallpike maneuver and supine roll test
• Audiogram if hearing loss is present
• Video- or electronystagmogram to evaluate vestibular function
• MRI brain if central causes are suspected 1

In summary, EEG has very limited value in the evaluation of dizziness and vertigo with headache unless there are specific features suggesting epilepsy. A focused vestibular examination and consideration of common causes like vestibular migraine should guide the diagnostic approach.