[Various ultrasound methods for studying the vertebral artery--a comparative evaluation]

Area of Science:

• Vascular Neurology
• Diagnostic Imaging
• Medical Ultrasound

Background:

• Vertebral artery pathology can lead to serious neurological complications.
• Accurate diagnosis of vertebral artery stenosis, hypoplasia, and occlusion is crucial for patient management.
• Non-invasive ultrasound techniques are widely used for evaluating the vertebral arteries.

Purpose of the Study:

• To compare the diagnostic accuracy of extracranial continuous-wave (CW) Doppler sonography, transcranial Doppler (TCD) sonography, and color-coded duplex sonography for vertebral artery (VA) pathology.
• To assess the sensitivity and specificity of different Doppler sonography methods in detecting VA abnormalities.
• To evaluate the utility of these methods in differentiating between VA hypoplasia, stenosis, and occlusion.

Main Methods:

• Prospective study involving 451 patients.
• Evaluation using extracranial CW Doppler sonography, TCD sonography, and color-coded duplex sonography.
• Color duplex sonography served as the reference standard for diagnosis.

Main Results:

• CW-Doppler sonography demonstrated 100% sensitivity but only 27% specificity for VA pathology.
• Suboccipital TCD sonography showed 38% sensitivity and 58% specificity.
• Both extracranial and TCD sonography were often inadequate for distinguishing VA hypoplasia from proximal stenosis.
• TCD sonography of terminal VA segments yielded normal flow in 27% of proximal stenosis and 50% of proximal occlusion cases due to collateral circulation.

Conclusions:

• CW-Doppler sonography is highly sensitive but not specific for detecting vertebral artery pathology.
• Transcranial Doppler sonography has limitations in diagnosing VA stenosis and occlusion, especially when collateral flow is present.
• Color-coded duplex sonography is a more reliable method for evaluating vertebral artery disease compared to CW and TCD sonography alone.