Vertebrobasilar insufficiency: evaluation by quantitative duplex flow measurements. A preliminary report

Area of Science:

• Vascular Surgery
• Neurology
• Diagnostic Imaging

Background:

• Vertebrobasilar insufficiency presents with nonlocalizing symptoms.
• Accurate diagnosis is crucial for effective treatment of cerebrovascular disease.

Purpose of the Study:

• To evaluate duplex sonography for hemodynamic assessment of vertebrobasilar insufficiency.
• To correlate vertebral artery flow with carotid artery stenosis and symptom type.

Main Methods:

• Duplex sonography was used to measure quantitative vertebral artery flow in 283 patients.
• Net vertebral artery flow was calculated by summing right and left side flows.
• Patients were categorized based on nonlocalizing symptoms, asymptomatic status, or lateralizing hemispheric symptoms.

Main Results:

• A net vertebral flow >200 ml/min was associated with significant carotid stenosis in 60% of patients.
• A net vertebral flow <200 ml/min was linked to normal or mildly diseased carotid arteries in 75% of patients (p<0.001).
• Nonlocalizing symptoms were more frequent in patients with low net vertebral flow (48%) compared to asymptomatic (35%) or hemispheric symptom groups (35%).

Conclusions:

• Duplex sonography provides a noninvasive method for hemodynamic evaluation of suspected vertebrobasilar insufficiency.
• This technique can help differentiate causes of symptoms, including carotid artery disease and true vertebrobasilar ischemia.