Twenty Years of Cerebral Ultrasound Perfusion Imaging—Is the Best yet to Come?

Abstract

Over the past 20 years, ultrasonic cerebral perfusion imaging (UPI) has been introduced and validated applying different data acquisition and processing approaches. Clinical data were collected mainly in acute stroke patients. Some efforts were undertaken in order to compare different technical settings and validate results to gold standard perfusion imaging. This review illustrates the evolution of the method, explicating different technical aspects and milestones achieved over time. Up to date, advancements of ultrasound technology as well as data processing approaches enable semi-quantitative, gold standard proven identification of critically hypo-perfused tissue in acute stroke patients. The rapid distribution of CT perfusion over the past 10 years has limited the clinical need for UPI. However, the unexcelled advantage of mobile application raises reasonable expectations for future applications. Since the identification of intracerebral hematoma and large vessel occlusion can also be revealed by ultrasound exams, UPI is a supplementary multi-modal imaging technique with the potential of pre-hospital application. Some further applications are outlined to highlight the future potential of this underrated bedside method of microcirculatory perfusion assessment.

How to Perform Intra-Operative Contrast-Enhanced Ultrasound of the Brain—A WFUMB Position Paper

“…Two articles have posed safety concerns regarding the risk of brain hemorrhage or bloodÀbrain barrier breakdown related to transcranial CEUS (Daffertshofer et al 2005;Reinhard et al 2006). However, the technical protocol applied in both used long-lasting US frequencies much lower than that of ioCEUS (Eyding et al 2020). Kastler et al (2014) did not report any adverse events after UCA injection in their cohort of neonates and infants with brain hemorrhages and hypoxic-ischemic injuries evaluated in an emergency setting using transfontanellar CEUS.…”

Advances in translational imaging of the microcirculation

“…Cerebral ultrasound perfusion imaging has been used to detect acute stroke, but due to technical limitations has been mostly supplanted by CT imaging. 178 In myocardial contrast echocardiography (MCE), air-filled microbubbles are administered intravenously and imaged in the myocardium. An ultrasound pulse is used to destroy the microbubbles, and the reaccumulating of microbubbles in the myocardium reflects myocardial blood flow (MBF).…”

“…Additionally, contrast‐enhanced US methods primarily use microbubbles to measure perfusion as a surrogate marker of the microcirculation. Cerebral ultrasound perfusion imaging has been used to detect acute stroke, but due to technical limitations has been mostly supplanted by CT imaging 178 . In myocardial contrast echocardiography (MCE), air‐filled microbubbles are administered intravenously and imaged in the myocardium.…”

Updates in Stroke Treatment, Diagnostic Methods and Predictors of Outcome

“…Most physicians use their own clinical experience in predicting their patients' outcomes after a stroke, as accurate prognostic models and tests of functional recovery in stroke patients are lacking to date [22].…”