Intracarotid injection of hyperosmolar mannitol produced a larger infarct than normal saline during the first few hours of distal middle cerebral artery occlusion with a smaller regional plasma volume

Our findings suggest that when intracranial pressure effect is excluded, hyperosmolar mannitol may exacerbate neuronal damage in the very early stages of acute ischemic stroke, and that cerebral regional plasma volume plays an important role in neuronal survival.