Perivascular anoxia-ischemia lesions in the human brain.

The clinical and pathologic data are presented on three patients who had clinical anoxia-ischemia in combination with serum hyperosmolality. The pathologic lesions consisted of perivascular necrosis, predominantly involving small vessels in the cerebral cortex. No intraluminal thromboembolic material was found in any of the vessels. The lesions are reminiscent of "no-reflow" lesions seen in experimental animals rendered ischemic.