Part 1: Ischemic Stroke: Pathophysiology and Principles of Localization
Matthew Brandon Maas, MD, and Joseph E. Safdieh, MD
Dr. Maas is a fellow in Stroke and Neurocritical Care, Harvard Medical School, Departments of Neurology, Massachusetts General and Brigham and Womens Hospitals, Boston, MA. Dr. Safdieh is an assistant professor of neurology, Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, NY.
A 28-year-old woman is found on the floor by a friend. The patient is a known intravenous heroin user. On arrival to the hospital, the patient is obtunded. She receives several doses of naloxone, but her mental status fails to improve. On examination, she is unresponsive except for decorticate posturing in response to noxious stimulation. Brainstem reflexes are intact. Diffusion-weighted magnetic resonance imaging (MRI) is performed 1 week later (Figure). What is the most likely mechanism of this patients neurologic impairment?
Figure. Magnetic resonance image obtained in evaluation of patient in question 2. (Reprinted with permission from Barrett KM, Freeman WD, Weindling SM, et al. Brain injury after cardiopulmonary arrest and its assessment with diffusion-weighted magnetic resonance imaging. Mayo Clin Proc 2007;82: 828–35.)
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