Brain microembolism.

ABSTRACT

PURPOSE: To alert clinicians about the occurrence of a subtype of brain infarction, its suspected etiology, and its detection by specific neuroimaging techniques. METHODS: The article presents 5 nonconsecutive patients admitted to the stroke services of 2 tertiary care hospitals, who presented with acute or subacute symptoms suspicious, but at times atypical, of brain ischemia. FINDINGS: Each patient had evidence of 3 to > 20 small areas of recent brain infarction detected by diffusion-weighted imaging (DWI). When available, brain computerized tomography images were not helpful for the diagnosis of these recent infarcts. Most lesions were present on magnetic resonance imaging fluid-attenuated inversion recovery sequences, but the diffusion-weighted images allowed the determination of their acuity. Further evaluation revealed a potential source of embolism in each patient. Brain microembolism was suspected in all cases. CONCLUSION: Small and multiple areas of acute or subacute brain infarction occasionally present with clinical features atypical for brain embolism. They can be detected by magnetic resonance DWI studies.