[Cerebrovascular ultrasound diagnosis]

Introduction of color-coded duplex sonography has further increased diagnostic confidence of neurovascular ultrasound. Thus, reliable and noninvasive preoperative assessment of patients with carotid artery stenoses becomes feasible, preventing potential adverse effects of cerebral angiography. Moreover, reliable diagnosis of subtotal stenoses and occlusions of the carotid arteries is possible. Transcranial ultrasonography provides reliable assessment of cross-flow through the circle of Willis, and stenoses, occlusions and vasospasm of the major basal cerebral arteries. Transcranial color-coded duplex sonography identifies intracranial hemorrhage, cerebrovascular malformations and hydrocephalus but is inferior to neuroradiological techniques. It is likely that power Doppler sonography and transpulmonary contrast agents will provide an additional increase in diagnostic confidence of neurovascular ultrasonography. In the future, cerebral microemboli may become a marker for embolic activity of occlusive carotid artery and cardiac disease.