Correlation between Higher Brain Dysfunction and Cerebral Blood Flow after Carotid Artery Stenting

Area of Science:

• Neurology
• Vascular Surgery
• Neuroimaging

Background:

• Carotid artery stenting (CAS) is a procedure to treat carotid artery stenosis.
• Changes in higher brain function and cerebral blood flow (CBF) after CAS require further investigation.
• The impact of diffusion-weighted imaging (DWI) findings post-CAS on cognitive function is not well understood.

Purpose of the Study:

• To investigate changes in higher brain function and CBF following CAS.
• To explore the relationship between cognitive improvements and CBF.
• To assess the impact of high-intensity DWI spots on cognitive outcomes after CAS.

Main Methods:

• CAS was performed on 88 patients between September 2017 and September 2019.
• Higher brain function tests (Symbol Digit Modalities Test, Kana Pick-out Test II, Mini-Mental State Examination) were administered to 26 patients before, 1 week after, and 1-3 months after CAS.
• Correlation analysis was performed between cognitive changes, CBF, DWI findings, and patient characteristics.

Main Results:

• Significant improvements were observed in Symbol Digit Modalities Test and Kana Pick-out Test scores post-CAS.
• Higher brain function, specifically attention and working memory, showed significant improvement.
• A significant correlation was found between improved higher brain function and CBF in patients with severe stenosis (>60%), a Mini-Mental State Examination score ≤26, and no known dementia.
• High-intensity DWI spots after CAS did not significantly impact higher brain function.

Conclusions:

• CAS leads to significant improvements in higher brain function, including attention and working memory.
• Cognitive enhancement post-CAS is linked to improved CBF, particularly in patients with severe stenosis and mild cognitive impairment without dementia.
• Both prevention of ischemic events and preservation of higher brain function are critical considerations during CAS procedures.