Doppler sonography in basilar artery occlusion

Abstract

We have investigated 6,972 patients with directional continuous-wave Doppler sonography within the last three and a half years, and have derived criteria for the sonographic diagnosis of basilar artery occlusion or tight stenosis in conjunction with 1,071 retrograde brachial angiograms. By sonographic patterns, we have suspected obstruction of the basilar artery or of both distal vertebral arteries in nine cases. Either bilateral sonographic silence or the absence of a diastolic flow component of the vertebral arteries served as criteria in the sonographic evaluation. Angiography of the vertebro-basilar system, performed in eight cases, showed near or complete occlusion in the distal vertebrals or in the proximal basilar artery. Degrees of stenosis less than an 80 percent reduction in lumen diameter could not be detected sonographically. Two further basilar artery occlusions were detected by means of angiography despite negative Doppler sonography: one of these patients showed an extensive collateral circulation between the posterior inferior and the superior cerebellar arteries, and one patient had an occlusion only of the middle and rostral thirds of the basilar artery, the proximal third and the anterior inferior cerebellar arteries being widely patent. Thus, we believe that directional CW Doppler sonography is very useful in the diagnosis of near or complete occlusion of both distal vertebral arteries or of the proximal basilar artery.

Directional C-W Doppler sonography in the diagnosis of basilar artery disease.

“…17 " Recently, we demonstrated the reliability of Doppler sonography in detecting severe stenosis and occlusion of both distal vertebral arteries and/or the proximal basilar artery. 6 In this study, the correlation of directional c-w Doppler sonographic findings with the results of almost 2,000 retrograde brachial angiograms done on more than 1,500 patients indicates that the technique is also sufficient for identifying stenoses of the basilar artery with at least a 60% reduction in lumen diameter. The only prerequisites are quality recordings of the vertebral pulse curves to calculate the modified Pourcelot indices.…”

“…1 " 5 Previously, we reported the possibility of detecting a substantial increase in peripheral resistance of both distal vertebral and/or the proximal basilar arteries with Doppler pulse curves. 6 In the present study, the use of relative end-diastolic flow velocities of the vertebral arteries as circulatory resistance indices allowed, in comparison with age-matched controls, the sonographic detection of stenotic lesions of at least 60% reduction in lumen diameter in the vertebro-basilar system distal to the point of insonation. …”

“…6 With a conventional 4-MHz hand-held probe, the optimal signals of the vertebral arteries at their atlas loops and in the supraclavicular fossae were obtained by acoustic and oscillographic control.…”

Radiologic Importance of a High-Resistive Vertebral Artery Doppler Waveform on Carotid Duplex Ultrasonography

“…Although conventional angiography remains the reference standard for assessing the vertebrobasilar circulation, it is invasive and reserved for patients for whom there is a strong neurologic indication. Although previous studies have shown a correlation between Doppler ultrasonography of the VAs and angiographic findings, 1,3,4 to our knowledge, ours is the largest to investigate the correlation between a single Doppler waveform of the V2 segment of the VA and correlative neuroimaging in an unselected patient population referred for CDU. Because of the differing modes of neuroimaging we used as the comparator studies (CTA, MRA, and angiography), calculation of the sensitivity or specificity of a single VA waveform to detect vertebrobasilar disease was not performed.…”

“…Complete evaluation of the VAs with CDU is limited by its intraforaminal course with considerable acoustic shadowing and dropout of the Doppler signal. Based on the Intersocietal Commission for the Accreditation of Vascular Laboratories standards for extracranial cerebrovascular testing, in addition to the evaluation of the common, internal, and external carotid arteries, bilateral VAs are identified and, at minimum, a single midartery Doppler signal is obtained for each cervical VA. 2 Although an HR Doppler signal in the cervical VA may indicate disease located cephalad to the ultrasound probe, ultrasonographic-angiographic correlation studies have been limited by small numbers of angiographic correlations 1,3 or by preselection of patients with neurologic symptoms. 4 Thus, the clinical importance of an HR pulsed Doppler VA waveform in an unselected patient population presenting for routine carotid ultrasonography remains uncertain.…”