A new simple method using carotid duplex ultrasonography to assess intracranial vertebrobasilar arterial stenosis.

OBJECTIVES Magnetic resonance angiography (MRA), three-dimensional computed tomography angiography, and cerebral angiography may be used to assess intracranial vertebrobasilar stenosis. However, these examinations cannot be performed at patients' bedsides. Our purpose was to develop a new bedside method to assess intracranial vertebrobasilar arterial stenosis. METHODS We developed the new method using carotid duplex ultrasonography combined with the head-up test. A total of 141 subjects admitted between June 1, 2017 and March 31, 2019 were enrolled in this study. We calculated vertebral arterial peak systolic velocities (PSVs), end-diastolic velocities (EDVs), and mean velocities (MVs) at 0°, 16°, and 30° head-up angles. Vertebrobasilar arterial stenosis was confirmed using MRA. RESULTS We excluded 28 subjects and included data for 113 subjects and 226 vessels in the final analysis. Cervical vertebral arterial PSV, EDV, and MV gradually decreased from 0° to 30° only in stenotic intracranial vertebral arteries. Sensitivity (probability of detection) was 75.5% and specificity (true negative rate) was 79.7% when EDV at the 30° head-up angle decreased ≥19.5% from the initial 0° head-up angle. Specificity was better (86.4%; sensitivity: 69.4%) when EDV was <9.1 cm/s at the 30° head-up angle. CONCLUSION This new method easily detects intracranial vertebrobasilar arterial stenosis.