Cerebrovascular ultrasound

Rapid progress in noninvasive ultrasound techniques has resulted in a wide variety of clinical applications for assessment of both extracranial and in tracranial arterial diseases. Recent highlights in cerebrovascular ultrasou nd research include imaging methods for characterization of intracranial an eurysms, use of echocontrast agents for improved evaluation of acute stroke patients and transient response harmonic imaging for depiction of brain pe rfusion. The important role of transcranial Doppler microembolism detection in carotid endarterectomy has been defined, new approaches to noninvasive Doppler measurement of intracranial pressure are progressing, and the clini cal indications for transcranial Doppler monitoring of intracranial vasospa sm to prevent secondary stroke have expanded. New functional transcranial D oppler applications, which are complementary to positron emission tomograph y and functional magnetic resonance imaging studies, are evolving for evalu ation of functional recovery after stroke; investigation of perfusion asymm etries during complex spatial tasks; assessment of hemispheric dominance in surgical candidates for epilepsy surgery; and elucidation of temporal patt erns of regional neuronal activity. With increasing sophistication of cereb rovascular ultrasound methodology, it is essential that standards for data acquisition and interpretation be established. Three recent consensus meeti ngs have provided detailed recommendations on quantification of carotid art ery stenosis, on characterization of carotid artery plaques and on microemb olism detection by transcranial Doppler. Curr Opin Neurol 12:57-63. (C) 199 9 Lippincott Williams & Wilkins.