Doppler sonography in basilar artery occlusion.

Area of Science:

• Neurology
• Vascular Imaging
• Diagnostic Sonography

Background:

• Vertebro-basilar system occlusive diseases pose significant diagnostic challenges.
• Accurate and timely diagnosis is crucial for patient management and outcomes.

Purpose of the Study:

• To establish criteria for diagnosing basilar artery occlusion or stenosis using directional continuous-wave Doppler sonography.
• To evaluate the efficacy of Doppler sonography compared to angiography in detecting these conditions.

Main Methods:

• Investigated 6,972 patients using directional continuous-wave Doppler sonography.
• Correlated sonographic findings with 1,071 retrograde brachial angiograms.
• Defined sonographic criteria including bilateral silence or absent diastolic flow in vertebral arteries.

Main Results:

• Sonography suspected obstruction in nine cases, confirmed by angiography as near or complete occlusion.
• Detected stenoses <80% lumen reduction were not identifiable sonographically.
• Angiography identified two additional basilar artery occlusions missed by sonography due to collateral circulation or specific occlusion patterns.

Conclusions:

• Directional continuous-wave Doppler sonography is highly useful for diagnosing near or complete occlusions of distal vertebral arteries or the proximal basilar artery.
• Sonography is a valuable non-invasive tool for evaluating the vertebro-basilar system.
• Limitations exist for detecting subtle stenoses or occlusions with extensive collateralization.