Extracranial–intracranial (EC-IC) arterial bypass surgery was developed to prevent
subsequent stroke by improving hemodynamics distal to the occluded intracranial artery,
but its utilization has been decreasing due to the development in medical treatment.
However, EC-IC bypass surgery may be effective for arresting or reversing cognitive
decline in patients with cerebral ischemia. A 69-year-old man with the left internal
carotid artery occlusion that manifested as scattered cerebral infarction of the left
hemisphere presented with dysarthria and transient right hemiparesis. Hemodynamic
condition was impaired in the left side, and therefore, EC-IC bypass surgery was performed
to prevent recurrence of cerebral infarction. Neuropsychological examination at 6
months after the surgery showed marked improvement as compared to the preoperative
examination and there was no recurrence of stroke in the patient. EC-IC bypass may
contribute to the improvement of cognitive function as well as the prevention of recurrence
of cerebral infarction in patients with hemodynamic insufficiency, but there might
be a threshold of hemodynamic impairment with respect to the reversibility of cognitive
performance. Investigation of the target and timing can identify cases in which the
cognitive function is improved by surgery.
Key-words:
Cerebral ischemia - cognitive function - extracranial–intracranial bypass - intracranial
steno-occlusive disease
