Background and purpose: Chronic cerebral hypoperfusion may lead to impairment in neurocognitive performance in patients with chronic internal carotid artery occlusion, and the effects of carotid artery stenting on neurocognitive function have been unclear.
Methods: We prospectively enrolled 20 chronic internal carotid artery occlusion patients with objective ipsilateral hemisphere ischemia, in whom carotid artery stenting was attempted. Functional assessments, including the National Institutes of Health Stroke Scale, Barthel Index, and a battery of neuropsychological tests, including the Mini-Mental State Examination, Alzheimer Disease Assessment Scale-Cognitive Subtest, verbal fluency, and Color Trail Making A and B, were administered before and 3 months after intervention.
Results: Successful recanalization was achieved in 12 of 20 patients (60%). There was no procedural or new cerebral ischemic event, except for 1 intracranial hemorrhage, which occurred during the procedure and had neurologic sequelae; this case was excluded from analysis. The demographics and baseline cognitive performance were similar between the group with a successful outcome (group 1, n=12) and patients who did not (group 2, n=7). Ten of 12 patients in group 1 had improvement in ipsilateral brain perfusion after the procedure, but none in group 2 had improvement. Significant improvement in the scores on the Alzheimer Disease Assessment Scale-Cognitive Subtest (before, 7.7±8.9 versus after, 5.7±7.1; P=0.024), Mini-Mental State Examination (before, 25.8±3.8 versus after, 27.7±2.7; P=0.015), and Color Trail Making A (before, 123.2±68.6 versus after, 99.3±51.5; P=0.017) were found in group 1 but not in group 2.
Conclusions: Successful carotid artery stenting improves global cognitive function as well as attention and psychomotor processing speed in patients with chronic internal carotid artery occlusion.