Transient neurological deficits simulating transient ischemic attacks in a patient with meningioma--case report.

A 67-year-old female had a history of transient neurological deficits involving fainting and right-sided hemiparesis. Magnetic resonance imaging showed a sphenoid ridge meningioma on the left, which had encased the internal carotid and middle cerebral arteries. Carotid angiography showed occlusion of the left internal carotid artery, a tumor stain, and engorgement of the surrounding cortical veins. Xenon-enhanced computed tomography showed reduced cerebral blood flow and poor response to acetazolamide in the surrounding brain tissue. The tumor was totally removed. Postoperatively, the patient had no more transient neurological deficits, and the response to acetazolamide was fully restored. An intracranial tumor may cause transient neurological deficits by reducing the cerebral perfusion pressure. This vascular insufficiency may occur when the tumor occludes major cerebral arteries, steals flow from the surrounding tissue, increases focal tissue pressure, and impedes regional venous outflow. The latter two factors were probably responsible in this patient.