[Ultrasound diagnostics of extracranial cerebral arteries].

Color-coded duplex sonography (CCDS) remains the primary angiological method for most clinical cerebrovascular problems. The application of ultrasound is a non-invasive, cost-effective and arbitrarily repeatable examination technique. Simultaneous acquisition of morphologic B‑mode images and hemodynamic parameters with high temporal and spatial resolution is unequalled by any other neurovascular imaging modality. The correct and reproducible use of CCDS requires knowledge of technical details and adequate examination techniques. Its multiparametric approach uses main and additional criteria to detect and precisely quantify clinically highly relevant stenosis of the proximal internal carotid artery. Quantification of vertebral artery stenosis is performed semiquantitatively due to the generally less reliable sonographic approach. The use of CCDS plays an essential role in supporting endovascular and operative procedures as well as in monitoring hemodynamically relevant dissections.