Decreased 13Nlabeled ammonia uptake in the ipsilateral and contralateral hemispheres following carotid endarterectomy

Author：

E-ISSN： 1791-3004|12|5|6598-6604

ISSN： 1791-2997

Source： Molecular Medicine Reports, Vol.12, Iss.5, 2015-01, pp. : 6598-6604

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

Carotid artery plaques are a leading cause of ischemic stroke, and carotid endarterectomy (CEA) is one of the major treatment approaches for this disease. Changes in cerebral metabolism following CEA remain unclear. The present study aimed to evaluate the effect of cerebral ammonia metabolism following CEA using 13Nlabeled ammonia positron emission tomography (PET) in humans. A total of 20 patients were enrolled in the present study, with a mean age of 59.5 years, comprising 16 males and four females. Of these patients, eight underwent right CEA and 12 underwent left CEA. The rate of carotid artery stenosis was between 5069% in six of the patients, between 7099% in 11 of the patients and was at 100% (thrombosis) in three of the patients, measured by computerised tomography digital subtraction angiography prior to CEA. 13Nlabeled ammonia (137 MBq) PET scanning was performed prior and subsequent to CEA surgery for each patient. The first ammonia PET scan was performed 1 day prior to CEA, while the second PET scan was performed 14 weeks following CEA. Following injection of 13Nlabeled ammonia, static PET was acquired for 10 min. The region of interest (ROI), covering the major cerebral hemisphere, was selected and ammonia uptake in the ROI was determined in the ipsilateral and contralateral hemispheres. No hyperperfusion syndrome was observed in the patients subsequent to CEA. No significant change in cerebral hemisphere ammonia uptake was observed between the ipsilateral and contralateral hemispheres prior to (ratio =0.98; P>0.01) or following (ratio =1.09; P>0.01) CEA. Ammonia uptake in the ipsilateral and contralateral hemispheres was significantly reduced to 23.2 and 23.5%, respectively, following CEA. Using 13Nlabeled ammonia PET to evaluate cerebral ammonia metabolism following CEA in patients with severe carotid artery stenosis, the present study demonstrated that uptake of ammonia in the ipsilateral and contralateral hemispheres was significantly reduced.