Unilateral white matter necrosis following carotid endarterectomy.

The authors report the first known example of hypoxic-ischemic white matter necrosis limited to one cerebral hemisphere. The patient was a 63-year-old man who developed signs of a stroke following a myocardial infarct after a left carotid endarterectomy and died seven days later. At autopsy, extensive necrosis of centrum semiovale was found only in the cerebral hemisphere supplied by the endoarterectomized carotid artery. A recent thrombus was found at the site of the endarterectomy, and the right common carotid artery was completely occluded by an old thrombus. This observation probably is explained by a well-established collateral blood supply to the right cerebral hemisphere, which protected it from the effects of the hypotension that accompanied the myocardial infarct.