What is the appropriate evaluation and management of a patient presenting with dizziness?

Evaluation of Dizziness

Initial Categorization by Timing and Triggers

Focus on timing and triggers rather than the patient's vague description of "spinning" versus "lightheadedness" to categorize dizziness into specific vestibular syndromes that will guide your diagnostic approach. 1, 2

Classify dizziness into one of four vestibular syndromes based on temporal patterns 1, 2:

• Brief episodic vertigo: Seconds to minutes of vertigo triggered by head movements (suggests BPPV) 1
• Acute persistent vertigo (Acute Vestibular Syndrome): Days to weeks of constant symptoms 1, 2
• Spontaneous episodic vestibular syndrome: Recurrent episodes without clear triggers (suggests Ménière's disease or vestibular migraine) 1
• Chronic vestibular syndrome: Persistent symptoms lasting months 1

Critical History Elements

Obtain specific details about 1, 2:

• Duration and onset: Exact timing of symptom onset and how long episodes last 1, 2
• Positional triggers: Does head movement or position change provoke symptoms? 1, 2
• Associated symptoms:
  • Hearing loss, tinnitus, or aural fullness suggest Ménière's disease 1
  • Headache, photophobia, and phonophobia suggest vestibular migraine 1
  • Neurological symptoms (diplopia, dysarthria, numbness, weakness) indicate central causes 2

Physical Examination

For All Patients with Dizziness

• Observe for spontaneous nystagmus in primary gaze and with gaze holding 2
• Perform complete neurologic examination to identify focal deficits 1
• Conduct otologic examination to assess for structural abnormalities 1

For Brief Episodic Vertigo (Suspected BPPV)

• Perform Dix-Hallpike maneuver for posterior canal BPPV 1, 2
• Perform supine roll test for horizontal canal BPPV 1, 2

For Acute Persistent Vertigo (Acute Vestibular Syndrome)

The HINTS examination (Head Impulse, Nystagmus, Test of Skew) is more sensitive than early MRI for detecting posterior circulation stroke when performed by trained practitioners (sensitivity 100% vs 46%). 1 However, when performed by non-experts, results are less reliable and should not be used to exclude stroke 1.

HINTS examination components 1:

• Head impulse test: Abnormal (corrective saccade) suggests peripheral cause; normal suggests central cause
• Nystagmus pattern: Direction-changing or vertical nystagmus suggests central cause
• Test of skew: Vertical misalignment suggests central cause

Imaging Decisions

When NO Imaging is Indicated

• Brief episodic vertigo with typical BPPV features on Dix-Hallpike or supine roll test 1
• Acute persistent vertigo with normal neurologic exam AND HINTS examination consistent with peripheral vertigo performed by a trained examiner 1

When MRI Head Without Contrast is Recommended

Order MRI brain with diffusion-weighted imaging for 1, 2:

• Acute persistent vertigo with abnormal neurologic examination 1
• HINTS examination suggesting central cause 1
• High vascular risk patients with acute vestibular syndrome 1
• Unilateral tinnitus or pulsatile tinnitus 1
• Asymmetric hearing loss 1
• Focal neurological abnormalities 1

Role of CT Imaging

CT head without contrast may be appropriate before MRI in acute settings when stroke is suspected, but has a low detection rate in isolated dizziness and should not be used instead of MRI when stroke is suspected, as CT misses many posterior circulation infarcts 1, 2.

Additional Diagnostic Testing

• Comprehensive audiologic examination for patients with unilateral tinnitus, persistent symptoms, or associated hearing difficulties 1
• Orthostatic vital sign measurement for patients with simple orthostatic dizziness without positional triggers to diagnose orthostatic intolerance 3

Treatment Based on Diagnosis

Benign Paroxysmal Positional Vertigo (BPPV)

Canalith repositioning procedures (Epley maneuver) are first-line treatment for BPPV, and no imaging or medication is needed for typical cases. 1, 4

Ménière's Disease

• Salt restriction and diuretics 1
• Intratympanic treatments in refractory cases 1

Vestibular Migraine

• Migraine prophylaxis and lifestyle modifications 1

Vestibular Neuritis

• Steroids for acute vestibular neuritis 5
• Vestibular rehabilitation exercises 4

Symptomatic Treatment

Meclizine 25 mg to 100 mg daily in divided doses may be used for symptomatic treatment of vertigo associated with vestibular system diseases, though pharmacologic intervention is limited because it often affects the central nervous system's ability to compensate for dizziness 6, 4.

Red Flags Requiring Urgent Evaluation

These findings mandate immediate imaging and neurologic consultation 1, 2:

• Focal neurological deficits 1
• Sudden hearing loss 1
• Inability to stand or walk 1
• Downbeating nystagmus or other central nystagmus patterns 1
• New severe headache 1
• Failure to respond to appropriate vestibular treatments 1

Critical Pitfalls to Avoid

• Do not assume a normal neurologic exam excludes stroke: 75-80% of patients with acute vestibular syndrome from posterior circulation infarct have no focal neurologic deficits 1
• Do not rely on patient's description of "spinning" versus "lightheadedness": Instead focus on timing and triggers 1
• Do not perform routine imaging for isolated dizziness: Most findings are incidental with low diagnostic yield 1
• Do not skip positional testing: Even patients with orthostatic dizziness may have BPPV, which was found in 37.1% of patients presenting with combined positional and orthostatic dizziness 3
• Do not rely on HINTS examination performed by non-experts to exclude central causes 1