Middle cerebral artery occlusion as a cause of isolated subcortical infarction.

We report two patients with large subcortical hemispheric infarctions, located in areas prone to the development of lacunes, who had occlusion of the middle cerebral artery demonstrated by arteriography. The cortical vessels were perfused by leptomeningeal collaterals. We suggest that large vessel arterial disease should be considered as a possible etiology of large subcortical infarctions and propose that the term lacune should not be used in cases in which neither the size nor the pathophysiologic mechanism of the lesion conform to C.M. Fisher's description.