J Neurosonol Neuroimag.  2024 Dec;16(2):63-70. 10.31728/jnn.2024.00165.

Microembolic Signals on Transcranial Doppler Ultrasonography: A Narrative Review of a Decade of Evidence

• Heo J

• KMID: 2563319
• DOI: http://doi.org/10.31728/jnn.2024.00165

Abstract

Microembolic signals (MESs), detected via transcranial Doppler ultrasonography, are essential biomarkers for assessing cerebrovascular risk, embolic events, and treatment outcomes. In this review, studies published between 2014 and 2024 were evaluated, specifically focusing on the clinical implications, associated conditions, and opportunities for advancements in MES monitoring technologies. A systematic PubMed search identified 327 articles, of which 60 were finally included in this review. MESs are associated with various conditions, including carotid/cerebral artery stenosis and atrial fibrillation. They predict adverse outcomes, including increased stroke risk, cognitive decline, and complications from procedures such as endovascular thrombectomy and unruptured aneurysm coiling. Furthermore, MESs serve as a surrogate marker for embolism, allowing for the evaluation of different procedural techniques to determine which approach minimizes embolic events. Advances in MES monitoring, including algorithms that distinguish gaseous and solid emboli and applications in pediatric cardiac surgery, have expanded its clinical utility. Moreover, emerging wearable and wireless technologies may expand the possibilities for MES monitoring.

Keyword

microembolic signals; transcranial Doppler ultrasonography; stroke risk; biomarkers