Can we discriminate stroke mechanisms by analyzing the infarct patterns in the striatocapsular region?

BACKGROUND AND AIMS: The aims of our study were to elucidate the differences in the distribution of acute middle cerebral artery (MCA) infarctions involving the striatocapsular region and to compare those following embolic striatocapsular infarctions with those originating from MCA disease (MCAD).

METHODS: We prospectively enrolled patients with acute large infarcts located in the lenticulostriate artery territory. Brain coronal diffusion-weighted imaging (DWI) and magnetic resonance angiography were carried out in all patients. The types of infarct distribution were divided into 3 categories: (1) dominant in the distal territory (DD), (2) distributed equally between the distal and proximal territories (DE) and (3) dominant in the proximal territory. Stroke mechanisms were classified into stroke from proximal embolism, MCAD and stroke of undetermined etiology.

RESULTS: A total of 71 patients were recruited. Proximal embolic sources were significantly more prevalent in patients with a DE lesion, but symptomatic MCA stenoses were more common in patients with a DD lesion than in those with a DE lesion.

CONCLUSION: These results suggest that the dominant area of striatocapsular infarctions on coronal DWI can be an important clue for stroke etiology.