SONOGRAPHIC DETECTION OF HEMODYNAMIC-CHANGES IN A CASE OF VERTEBROBASILAR INSUFFICIENCY

We present a diagnostically challenging case of vertebrobasilar insuff iciency caused by head rotation. The patient was a 58-year-old man com plaining of dizziness and faintness with head rotation to the left. Ve rtebral arteriography with the head turned to the left revealed mechan ical compression of the right vertebral artery at the occipitoatlantal joints and an occluded left vertebral artery. Duplex sonography demon strated disappearance of the end-diastolic flow signal in the right ve rtebral artery on head rotation, paralleling the appearance of symptom s. Decompression of the vertebral artery by transversectomy of the atl as and hemilaminectomy of the axis completely relieved the symptoms an d the Doppler flow signal pattern of the vertebral artery returned to normal: End-diastolic flow in the right vertebral artery did not disap pear even when the head was rotated to the left.