title: Noninvasive evaluation of vertebrobasilar insufficiency.
abstract: The diagnosis of vertebrobasilar insufficiency (VBI) is a clinical challenge because its manifestations are subjective and difficult to quantify. We evaluate 61 patients with the clinical diagnosis of VBI and 30 control patients with other medical problems. We used duplex scanning to study the extracranial carotid, vertebral, and subclavian arteries, and a 2-MHz transcranial Doppler (TCD) to examine the intracranial vertebral and basilar arteries. Extracranial lesions were more common in VBI patients than among controls, including stenosis of the subclavian artery with and without subclavian-vertebral steal and stenosis of the vertebral artery. Intracranial abnormalities identified in the vertebrobasilar circulation included stenosis and occlusion of the intracranial vertebral artery and basilar artery steal. Overall, significant lesions were detected in 32.8% of VBI patients and 3.0% of controls (P less than 0.05). Systolic artery velocity (cm/sec) in the extracranial vertebral artery was higher in controls (65.9 +/- 23.3) than in VBI patients who had no evidence of vertebrobasilar steal (43.0 +/- 17.4, P less than 0.05). Patients with a steal mechanism had an intracranial vertebral artery systolic velocity of 90.0 +/- 38.9, compared with 53.0 +/- 15.0 in controls (2P less than 0.050). Intracranial vertebral artery systolic velocity was higher among VBI patients with significant carotid artery disease (greater than 50%, 76.7 +/- 28.8) than in those with less severe disease (less than 50%, 47.3 +/- 13.8, P less than 0.05). Evaluation and quantitation of the vertebrobasilar circulation using both intra- and extracranial noninvasive studies may afford further insight as to the pathophysiology of vertebrobasilar insufficiency and provide a readily available, direct, and simple method of initial and serial assessment of VBI patients.
authors.affiliation: Division of Vascular and Thoracic Surgery, Scripps Clinic and Research Foundation, La Jolla, California 92037.
authors.forename: P A
authors.initials: PA
authors.lastname: Schneider
authors.forename: M E
authors.initials: ME
authors.lastname: Rossman
authors.forename: E F
authors.initials: EF
authors.lastname: Bernstein
authors.forename: E B
authors.initials: EB
authors.lastname: Ringelstein
authors.forename: S
authors.initials: S
authors.lastname: Torem
authors.forename: S M
authors.initials: SM
authors.lastname: Otis
mesh_terms: D001157:Arterial Occlusive Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology; D001488:Basilar Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D001783:Blood Flow Velocity / Q000502:physiology; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D002340:Carotid Artery Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology; D004453:Echoencephalography; D006801:Humans; D008297:Male; D008875:Middle Aged; D011674:Pulse; D012039:Regional Blood Flow / Q000502:physiology; D013348:Subclavian Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D014711:Vertebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D014715:Vertebrobasilar Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology