What is the approach to evaluating a patient with dizziness?

Evaluation of Dizziness

The most effective approach to evaluating dizziness is to categorize patients based on timing and triggers rather than symptom quality, focusing on three key patterns: acute vestibular syndrome, spontaneous episodic vestibular syndrome, and triggered episodic vestibular syndrome. 1, 2

Initial Assessment Framework

1. Timing and Triggers Assessment

• Acute Vestibular Syndrome: Continuous dizziness lasting days
• Spontaneous Episodic Vestibular Syndrome: Recurrent unprovoked episodes
• Triggered Episodic Vestibular Syndrome: Episodes provoked by specific triggers (e.g., position changes)

2. Key Physical Examination Components

• HINTS examination (Head-Impulse, Nystagmus, Test of Skew) to differentiate peripheral from central causes 1
• Dix-Hallpike maneuver for suspected BPPV 1
• Supine roll test for horizontal canal BPPV 1
• Orthostatic vital signs (measure supine, then standing after 1-3 minutes) 1
• Complete neurological examination including cranial nerves, motor strength, coordination, and gait 1
• Cardiovascular examination including heart rate, rhythm, and auscultation for murmurs 1

Diagnostic Algorithm by Pattern

1. Acute Vestibular Syndrome

• Perform HINTS examination:
  • Normal head impulse test, direction-changing nystagmus, or skew deviation suggests central cause (stroke) 1, 2
  • Abnormal head impulse test, unidirectional nystagmus, and no skew deviation suggests peripheral cause (vestibular neuritis) 2
• Red flags requiring immediate MRI:
  • Abnormal HINTS examination
  • Associated neurological deficits
  • High vascular risk patients even with normal examination 1

2. Spontaneous Episodic Vestibular Syndrome

• Key differentiating features:
  • Vestibular migraine: History of migraine, light sensitivity, motion intolerance, mild/stable hearing loss 3
  • Menière's disease: Fluctuating hearing loss, tinnitus, aural fullness 3
  • TIA/stroke: Vascular risk factors, brief episodes, other neurological symptoms 2

3. Triggered Episodic Vestibular Syndrome

• Position-triggered (perform Dix-Hallpike and supine roll tests):
  • Positive tests suggest BPPV 1
  • Negative tests with persistent symptoms may require imaging for posterior fossa lesions 2

Targeted Testing Based on Clinical Suspicion

Laboratory Tests (selective ordering)

• CBC and electrolytes for orthostatic dizziness/presyncope
• Blood glucose/HbA1c for patients with diabetes or risk factors
• Electrolytes and renal function for patients on medications affecting electrolytes 1

Imaging

• MRI brain (without contrast) indicated for:
  • Acute vestibular syndrome with abnormal HINTS
  • Neurological deficits
  • High vascular risk patients
  • Chronic undiagnosed dizziness not responding to treatment 1

Common Diagnoses and Management

BPPV

• Treatment: Canalith repositioning procedure (Epley maneuver) for posterior canal BPPV; roll maneuvers for lateral canal BPPV 1, 4

Vestibular Neuritis

• Treatment: Short-term vestibular suppressants and vestibular rehabilitation 1, 4

Menière's Disease

• Treatment: Salt restriction and diuretics 4

Vestibular Migraine

• Treatment: Migraine prophylaxis and trigger avoidance 3

Orthostatic Hypotension

• Treatment: Volume expansion, medication adjustment, alpha agonists or mineralocorticoids for persistent cases 1

Red Flags and Pitfalls

Red Flags for Central Causes

• Ataxia symptoms
• History of previous stroke
• Diabetes mellitus
• Abnormal HINTS examination 1

Common Pitfalls to Avoid

• Overreliance on imaging
• Overuse of vestibular suppressants
• Failure to perform appropriate positional testing
• Missing red flags for central causes 1

The timing and triggers approach has been shown to be more effective than the traditional symptom quality approach (vertigo, presyncope, disequilibrium, lightheadedness), which is now considered outdated and less clinically useful 2, 5. This modern approach helps reduce misdiagnosis while decreasing unnecessary testing and hospitalizations 2.