Tracking the Cognitive Effects
of Carotid Endarterectomy
ANNE D. BAIRD
Henry Ford Health System
ELIZABETH M. PIEROTH
Schwab Rehabilitation Hospital
Carotid endarterectomy (CE) has been shown to reduce risk of stroke in selected patients. This surgery provides a rich opportunity for neuropsychologists to study patients who have cerebrovascular occlusive disease but have not yet had a major stroke. Well-controlled studies of sufficient power will elucidate the neuropsychological impact of surgical removal of major blockages in the blood flow to the brain.
Candidates for CE have significant narrowing in one or both internal carotid arteries. Individuals who undergo CE may have had no symptoms or may have experienced one or more transient ischemic attacks (TIAs) or mild strokes before surgery.
TIAs are episodes of focal neurological symptoms lasting less than 24 hr, whereas strokes are characterized by symptoms lasting a day or longer. Some clinicians and researchers also distinguish between reversible ischemic neurological deficits (RINDS), with symptoms lasting from a day to a week, and strokes, with symptoms lasting longer than 7 days (Dull et al., 1982.) Symptomatic episodes are not characterized as TIAs, RINDs, and strokes unless they are deemed to be the result of ischemia, an interruption of the blood supply to part of the brain.
Randomized trials showed definite stroke reduction following CE in two situations (Biller et al., 1998). First, CE was effective in reducing stroke risk in patients who had experienced focal neurological symptoms-usually aphasia or lateralized numbness or weakness-and who had narrowing of 70% to 99% of