Multiple acute stroke syndrome - Marker of embolic disease?

Objective: To determine the frequency and etiologic significance of multipl e acute ischemic lesions in stroke. Background: Although patients may have more than one stroke during the course of their lives, acute ischemic strok e is usually thought of as a single event. Using diffusion-weighted imaging (DWI), an MRI technique that detects ischemic injury within minutes after onset, we have often observed multiple acute ischemic lesions. Methods: The MRI scans of 59 consecutively studied patients were reviewed to determine the frequency and etiologic significance of multiple acute ischemic lesions on DWI. Results: Multiple acute ischemic lesions were present in 10 (17%) of 59 patients. The lesions usually occurred within one major circulation ( anterior or posterior), but in two patients (3%), lesions occurred in both cerebral hemispheres or in the anterior and the posterior circulations. The lesions often were small and resulted from presumed multiple emboli or the break-up of an embolus. Two patients had internal carotid artery occlusive disease and four had a cardiac or aortic source. In the other four patient s the source was not determined. Lesions larger than 1 cm in diameter progr essed to infarction, but some smaller lesions were not seen on follow-up T2 -weighted imaging. Conclusions: Multiple acute stroke lesions on DWI are co mmon and could be caused by multiple emboli or the breakup of an embolus. I n some cases it might become possible to make early inferences concerning t he stroke mechanism that could be of use for immediately directing the clin ical work-up and treatment of the patient.