# Carotid endarterectomy and blood-brain barrier permeability in subjects with bilateral carotid artery stenosis

## TL;DR

This study shows that carotid endarterectomy improves blood flow and reduces blood-brain barrier permeability in patients with severe carotid artery stenosis.

## Contribution

The study provides new evidence that carotid endarterectomy reduces blood-brain barrier permeability in patients with bilateral carotid stenosis.

## Key findings

- Before surgery, the affected side showed reduced cerebral blood flow and prolonged transit times compared to the nonoperative side.
- After carotid endarterectomy, the operative side showed significant improvements in perfusion and a 27.5% decrease in blood-brain barrier permeability.
- No significant changes were observed on the nonoperative side after surgery.

## Abstract

The increased permeability of the blood–brain barrier (BBB) is related to the occurrence and development of diseases such as acute ischemic stroke, chronic ischemia, or small vessel disease. Patients with carotid artery stenosis have chronic ischemia. The exact effect of carotid endarterectomy on the blood–brain barrier is still unclear. The aim of the study was to assess the effect of carotid endarterectomy on basic perfusion parameters and permeability surface area-product (PS).

The study included a total of 17 subjects (13 men), of which bilateral carotid artery stenosis was greater than 70%. All patients underwent unilateral carotid endarterectomy. Differences in the following computed tomography perfusion (CTP) parameters were compared before and after operation: cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and PS. PS acquired by CTP is used to measure the permeability of the BBB to contrast material.

Before surgery, the operative side exhibited significantly lower CBF (p = 0.001) and prolonged MTT (p = 0.002) and TTP (p = 0.001) compared to the nonoperative side, while PS and CBV showed no significant differences. After carotid endarterectomy, only the operative side demonstrated improvements, with CBV increasing by 9.4%, MTT decreasing by 20.3%, TTP decreasing by 14.1%, and PS decreasing by 27.5% (all p < 0.01). No significant changes were observed on the nonoperative side.

Carotid endarterectomy augmented BBB permeability can be controlled by carotid endarterectomy in patients with carotid artery stenosis.