Neurocognitive Changes and Cerebral Blood Flow in Patients with Symptomatic Carotid Artery Stenosis before and after Carotid Endarterectomy

Abstract

Objective Carotid endarterectomy (CEA) reduces stroke risk in carotid stenosis patients, with potential but unclear benefits on cognitive function and cerebral blood flow (CBF). This study aimed to assess cognitive and CBF changes after CEA in patients with transient ischemic attack (TIA) and severe symptomatic carotid artery stenosis, exploring the relationship between these changes. Methods In this prospective, observational study was conducted at Affiliated Hospital of Qingdao University between June 2021 and September 2022, and included patients with recent TIA and confirmed severe symptomatic carotid artery stenosis underwent CEA. Cognitive function was evaluated using the Montreal Cognitive Assessment (MoCA), and CBF was assessed through arterial spin labeling magnetic resonance imaging (MRI). Measurements were taken preoperatively and at 1 and 6 months postoperatively. Statistical analysis involved paired and independent t-tests, with p<0.05 considered significant. Results Forty-one patients (average age, 66.8 years; 75.6% male) were assessed. Initially, patients with left internal carotid artery (ICA) stenosis demonstrated naming ability scores significantly lower (2.8±0.4) than controls (3.0±0.2; p<0.05). Right ICA stenosis patients exhibited reduced MoCA scores (21.5±4.3) compared to controls (24.8±3.6, p<0.05). Significant improvements in cognitive performance and CBF were observed 1 month post-surgery, with sustained gains by 6 months. A positive association (R=0.437, p<0.01) was identified between increased CBF and cognitive improvement. Conclusion CEA may enhance cognitive function and CBF in patients with severe symptomatic carotid artery stenosis. The association between cognitive gains and increased CBF suggests cerebral hemodynamics may play a role as a potentially reversible factor influencing cognitive dysfunction in this population.