What are the typical presentation, diagnostic workup, and acute management for vertebrobasilar insufficiency in a middle‑aged to elderly patient with hypertension, hyperlipidemia, diabetes, smoking, or known atherosclerotic disease?

Vertebrobasilar Insufficiency: Clinical Approach

Typical Clinical Presentation

Vertebrobasilar insufficiency presents with chronic recurrent vertigo accompanied by other brainstem neurologic deficits, distinguishing it from isolated peripheral vestibular disorders. 1

Key symptoms to recognize include:

• Dizziness and vertigo (most common presenting symptoms) 2, 3
• Visual disturbances: diplopia, blurred vision, or transient blindness 2, 4
• Perioral numbness (highly specific for posterior circulation involvement) 2, 3
• Ataxia and imbalance (cerebellar dysfunction) 2, 4
• Bilateral sensory deficits (distinguishes from anterior circulation stroke) 3
• Tinnitus 2, 4
• Syncope (in severe cases) 3

Critical diagnostic pitfall: These symptoms are often mistaken for benign vestibular disorders, but the presence of any additional brainstem signs (diplopia, facial numbness, bilateral weakness) mandates urgent posterior circulation evaluation. 3

The underlying pathophysiology is most commonly atherosclerotic stenosis affecting the proximal (V1) segment of the vertebral arteries or their origins from the subclavian arteries, particularly in elderly patients with traditional vascular risk factors. 1, 2 Vertebral artery dissection is an alternative cause in younger patients, typically accompanied by headache or neck pain following trauma. 1

Diagnostic Workup Algorithm

Step 1: Immediate Vascular Imaging

CTA head and neck with IV contrast or contrast-enhanced MRA should be the first-line imaging modality, with sensitivity and specificity of 94% and 95% respectively for detecting vertebral artery stenosis or occlusion. 1, 3

• CTA has the highest reported sensitivity (100%) for vertebral artery dissection, superior to MRA (77%) and Doppler ultrasound (71%). 1
• The imaging must include the entire course from aortic arch origins through the basilar artery to capture all potential lesion sites. 1
• Duplex ultrasound is inadequate with only 70% sensitivity and should not be relied upon for diagnosis. 3

Step 2: Brain Parenchymal Assessment

Brain MRI is more sensitive than CT for detecting posterior fossa infarcts, which may be present even with transient symptoms. 1

• CT head without contrast may be useful for initial evaluation but will miss small brainstem or cerebellar infarcts. 1
• MRI sequences should specifically evaluate the brainstem, cerebellum, and thalami (the territories supplied by vertebrobasilar circulation). 1

Step 3: Catheter Angiography (When Indicated)

Catheter-based contrast angiography is indicated when noninvasive imaging fails to define the location or severity of stenosis in patients who are potential revascularization candidates. 3

High-Risk Screening Indications

Even asymptomatic patients require vertebral artery screening if they have:

• Bilateral carotid artery occlusions 3
• Unilateral carotid occlusion with incomplete circle of Willis 3

These anatomical scenarios create functional dependence on the vertebrobasilar system for cerebral perfusion. 5

Acute Management

Immediate Consultation

Any patient presenting with acute posterior circulation symptoms requires immediate neurologist or stroke team consultation to exclude acute basilar thrombosis, which carries extremely high mortality. 3

Medical Therapy (First-Line Treatment)

Antiplatelet therapy is the recommended first-line treatment, following guidelines similar to carotid artery disease management. 2

Specific regimens with evidence:

• Aspirin plus dipyridamole has demonstrated superiority over placebo, reducing recurrent vertebrobasilar territory strokes from 10.8% to 5.7%. 2
• Aspirin monotherapy is an acceptable alternative. 2
• Short-term anticoagulation may be indicated when acute thrombus is identified. 3

Aggressive Risk Factor Modification

All patients require intensive atherosclerotic risk factor control including:

• Hypertension management (reduces stroke risk with strong evidence in older adults) 1
• Statin therapy for hyperlipidemia (proven benefit up to early 80s) 1
• Diabetes control 1, 5
• Smoking cessation (within 5 years, stroke risk declines to that of never-smokers) 1

Surveillance Imaging

Serial noninvasive imaging with CTA or MRA is recommended to assess progression of atherosclerotic disease and exclude development of new lesions. 2, 3

Endovascular Intervention

Endovascular therapy should be reserved for patients with recurrent ischemic symptoms despite optimal medical therapy, as no randomized trial evidence supports its superiority over medical management. 5

Critical risk considerations:

• Periprocedural neurological complication risk: 5.5% 5, 3
• Procedural mortality: 0.3% 5, 3
• Patients with VBI have higher perioperative risk from revascularization compared to anterior circulation procedures 1
• Annual stroke risk after successful angioplasty is approximately 3%. 2

Surgical bypass is rarely indicated and should only be considered for the exceptional patient with large-vessel occlusions, poor collateral circulation, and persistent debilitating symptoms despite protracted maximal medical therapy. 6, 7 Surgical mortality ranges from 0-4% for proximal reconstructions and 2-8% for distal reconstructions. 3

Prognostic Information

Annual stroke rates for symptomatic intracranial vertebral and basilar artery stenosis are 8% and 11% respectively, underscoring the importance of aggressive medical management. 2, 5 Vertebral artery atherosclerosis accounts for approximately 20% of all posterior circulation strokes. 2, 5