Use of transcranial Doppler sonography to evaluate patients with cerebrovascular disease

Transcranial Doppler ultrasound (TCD) is a noninvasive technique that allows the examiner to assess blood flow velocity through the basal cerebral arteries. This article introduces the reader to some of the basics of TCD technology, technique, and interpretation. This introduction is followed by a summary of the many clinical applications for the evaluation of cerebrovascular disease including but not limited to vasospasm, atherosclerosis, and arteriovenous malformations. Lastly, some investigational applications including emboli detection, and intraoperative use are discussed.