Contrast-enhanced ultrasound (CEUS) is a new technology which improves the usefulness of ultrasoundin clinical medicine using ultrasound contrast agents (UCAs). Currently available UCAs areusually microbubbles which contain gaseous material in the core sized below 7 micrometer indiameter. Interaction between UCAs and media results in various physiologic changes according tothe properties of media and the changes are presented as enhancement in ultrasound images. Thefield of CEUS has been enlarged to assessment of vulnerability of carotid plaque, visualization ofnon-visible intracranial arteries during transcranial Doppler examination, and application as adjuvantfor sonothrombolysis. In this review, introduction about UCAs including physical properties, classification,and mechanism of interaction with media were presented. Furthermore, clinical studies ofCEUS in neurosonological field were also discussed.

Journal of Neurosonology 4(1):8-13, 2012
Key Words: Ultrasound contrast agent, Contrast-enhanced ultrasonography, Carotid plaque, Transcranial Doppler sonography, Microbubble