Initial Workup for Dizziness
Categorize dizziness by timing and triggers—not by symptom quality—to guide targeted physical examination and distinguish benign peripheral vestibular disorders from dangerous central causes like stroke. 1, 2
Classification Framework
Classify patients into one of three vestibular syndromes based on temporal pattern 1, 2:
- Triggered Episodic Vestibular Syndrome: Brief episodes (seconds to <1 minute) provoked by specific head position changes, most commonly BPPV 1, 2
- Spontaneous Episodic Vestibular Syndrome: Unprovoked episodes lasting minutes to hours without positional triggers, suggesting vestibular migraine or Ménière's disease 1, 2
- Acute Vestibular Syndrome (AVS): Continuous severe vertigo lasting days to weeks with constant symptoms, indicating vestibular neuritis, labyrinthitis, or posterior circulation stroke 1, 2
Critical History Elements
Focus on specific diagnostic details rather than vague descriptions 2, 3:
- Duration: Seconds (BPPV), minutes to hours (vestibular migraine, Ménière's), days to weeks (vestibular neuritis, stroke) 1, 2
- Triggers: Head position changes (BPPV), pressure changes (superior canal dehiscence), none (vestibular neuritis, stroke) 1, 2
- Associated symptoms:
Targeted Physical Examination
For Triggered Episodic Symptoms (Suspected BPPV)
Perform the Dix-Hallpike maneuver as the gold standard diagnostic test 2, 4:
- Positive findings: 5-20 second latency, torsional upbeating nystagmus toward affected ear, symptoms that increase then resolve within 60 seconds 2, 4
- If negative but history compatible, perform Supine Roll Test for lateral canal BPPV (10-15% of cases) 4
For Acute Vestibular Syndrome
Perform the HINTS examination (Head Impulse, Nystagmus, Test of Skew) to distinguish peripheral from central causes 1, 2:
- HINTS has 100% sensitivity for posterior circulation stroke when performed by trained practitioners, superior to early MRI (46% sensitivity) 1, 2
- Critical caveat: HINTS is unreliable when performed by non-experts 2, 4
- Complete neurologic examination including cranial nerves, cerebellar testing, and gait assessment 1
Imaging Decisions
No Imaging Indicated 1, 2
- Brief episodic vertigo with typical BPPV features and positive Dix-Hallpike 1, 2
- Acute persistent vertigo with normal neurologic exam and HINTS consistent with peripheral vertigo by trained examiner 1, 2
MRI Brain Without Contrast Indicated 1, 2, 4
- Abnormal neurologic examination 1, 2
- HINTS examination suggesting central cause 1, 2
- High vascular risk patients with acute vestibular syndrome 1, 2
- Unilateral or pulsatile tinnitus 1, 2
- Asymmetric hearing loss 1, 2
- Severe postural instability 4
CT head has extremely low diagnostic yield (<1%) for isolated dizziness and should not be used instead of MRI when stroke is suspected 1, 2
Red Flags Requiring Urgent Evaluation
Immediate imaging and neurologic consultation needed for 1, 2:
- Focal neurological deficits 1, 2
- Sudden hearing loss 1, 2
- Inability to stand or walk 1, 2
- Downbeating nystagmus or other central nystagmus patterns 1, 2
- New severe headache 2
- Failure to respond to appropriate vestibular treatments 1, 2
Common Diagnostic Pitfalls to Avoid
- Do not rely on patient's description of "spinning" vs "lightheadedness"—focus on timing and triggers instead 1, 2
- Do not assume normal neurologic exam excludes stroke—75-80% of patients with acute vestibular syndrome from posterior circulation infarct have no focal neurologic deficits 2, 4
- Do not order routine imaging for isolated dizziness—diagnostic yield is very low and most findings are incidental 2
- Do not use CT when stroke is suspected—CT misses many posterior circulation infarcts 2
Fall Risk Assessment
For all dizzy patients, assess fall risk 1:
- Ask about falls in past year, feeling unsteady, and worry about falling 1
- Perform Get Up and Go test or Tinetti Balance Assessment if positive responses 1
Medication Review
Medication side effects are a leading reversible cause of chronic dizziness 2: