Doppler sonography of the intertransverse segment of the vertebral artery.

We assessed the utility of a Doppler ultrasonographic examination of the vertebral artery, limited to the intertransverse segment, in diagnosis of disease at any level of vertebrobasilar circulation. The vertebral artery was identified in all the patients, with a successful evaluation of the presence of disease in 112 of 116 (96.5%) vertebral arteries. All of the occlusions and subclavian steal syndromes were diagnosed. All of the vertebral arteries with abnormal Doppler findings had a pathologic angiographic study. In conclusion, Doppler ultrasonography of the intertransverse segment of the vertebral artery is useful owing to its applicability and accuracy.