Objectives: To review techniques and the most important clinical applications of microembolus detection with transcranial Doppler.
Development: Technical aspects of microembolus detection are discussed initially; clinical circumstances in which embolus detection is currently used follow, such as carotid stenosis, cardiac pathology, monitoring during neuroangiography, coronary revascularization surgery and endarterectomy. Lastly, the potential clinical applications of this technique are reviewed: localization of an embolic source, risk of recurrent ischemia in patients with unstable atherosclerotic plaques, intraoperative monitoring and potential surgical technique modifications based on this information, contributions to the understanding of the pathophysiology of the fat embolism syndrome, and monitoring therapeutic efficacy of antithrombotics and thrombolytics.
Conclusions: The ability to detect cerebral emboli with transcranial ultrasound has increased significantly our understanding about the pathogenesis of cerebral ischemia. Microembolus detection with transcranial Doppler is a powerful and novel diagnostic technique that allows to study the embolic process in vivo and in real time, instead of using indirect indicators of embolism (clinical and radiological features, possible embolic sources, etc.).