Patients with high grade internal carotid artery stenosis intended to carotid artery stent are brought to this study. Global cognitive function and evoked cerebral blood oxygenation are evaluated before and after stent, followed up at 6 months later. Mini-Mental State Examination(MMSE) and Montreal Cognitive Assessment (MoCA) are used for the global cognitive test. Evoked cerebral blood oxygenation is evaluated using functional near-infrared spectroscopy(fNIRS) through performing mental task( N-back task, Go/no go task, and verbal fluency task ). All the patients from different centers are conducted the test at the only main center by one doctor. The parameter of fNIRS and score of cognitive test of each patient are compared before and after stent.
Cerebral hemodynamic compromise from internal carotid artery stenosis may be a cause of vascular cognitive impairment that is amenable to treatment by revascularization. The effect of carotid artery stent on evoked cerebral blood oxygenation and neurocognitive functioning will be evaluated by functional near-infrared spectroscopy. Carotid artery stent could benefit cerebral blood oxygenation after stent and improving neurocognitive functioning after 6 months.