Mechanisms of Cognitive Improvement After Carotid Endarterectomy: Results of an Autopsy
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Carotid endarterectomy
Cerebral blood flow
Cerebral metabolism
Small vessel diseases



Submitted : 2023-04-24
Accepted : 2023-05-09
Published : 2023-05-24


To develop a clinically meaningful definition of cognitive change before and after carotid endarterectomy (CEA), we categorized patients with “improved postoperative function” and “non-improved postoperative function” based on subjective assessment and neuropsychological tests. The results showed that 11% of the patients showed an improvement in postoperative function. Through single-photon emission computerized tomography (SPECT), positron emission tomography (PET), magnetic resonance imaging (MRI), etc., it was found that improvement of cerebral blood flow by carcinoembryonic antigen (CEA) → improvement of cerebral metabolism → improvement of cerebral cortical neuroreceptor function and cerebral white matter microstructure → improvement of cognitive function. The degree of preoperative cerebral hemispheric white matter lesions was the rate-limiting factor for improvement in cognitive function.


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