[Transoral Doppler ultrasound echography under local anaesthesia for the assessment of vertebral artery blood flow (author's transl)].

Uncalibrated flow in the vertebral arteries was registered with a bidirectional CW Doppler ultrsound apparatus. It was applied to 20 patients, results being compared with aortic arch angiograms in which the extracranial part of all four cerebral vessels was seen. In 14 the vertebral arteries had a symmetrical flow and lumen, a similar symmetrical result being obtained with the Doppler. Hypoplasia of one vertebral artery was present in two patients the distinct asymmetry being recorded by the ultrasound. Three patients with central stenosis in one subclavian artery and subclavian "steal" were found to have reverse flow by the Doppler method in the vertebral artery on the side of the stenosis. Endarterectomy was performed on the affected subclavian artery in two of these patients: post-operative vertebral ultrasound recordings demonstrated a return to physiological flow direction in both vertebral arteries.