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© 2009 American Academy of Neurology Cerebral hemodynamics and cognitive performance in patients with asymptomatic carotid stenosisFrom the Department of Neuroscience (M.S., I.P., R.B., B.G., C.C., L.P., M.B.), Marche Polytechnic University, Ancona; and Clinical Neurology (F.V.) and Geriatric Medicine (C.P.), University Campus Bio-Medico, Rome, Italy. Address correspondence and reprint requests to Prof. Mauro Silvestrini, Clinica Neurologica, Università Politecnica delle Marche, Via Conca 1, 60020 Ancona, Italy m.silvestrini{at}univpm.it. Objective: The aim of this study was to investigate whether the presence of severe internal carotid artery stenosis may be associated with different cognitive performance in relation to the side of the stenosis and its hemodynamic consequences.
Methods: Eighty-three patients with asymptomatic severe unilateral internal carotid stenosis were included. A neuropsychological investigation including Verbal Fluency using phonemic and category access, Coloured Progressive Matrices, and Complex Figure Test Copy was performed. Each patient underwent an assessment of cerebrovascular reactivity (CVR) to hypercapnia with transcranial Doppler ultrasonography using the breath-holding index (BHI). Thirty healthy subjects comparable for demographic characteristics and vascular risk profile served as controls. Subjects with carotid stenosis were classified into two groups: preserved CVR (BHI Results: Subjects with left stenosis and reduced CVR had significantly lower performances at phonemic verbal fluency with respect to controls and the other groups of stenosis. In subjects with right stenosis and reduced CVR, scores obtained in Coloured Progressive Matrices and in Complex Figure Test Copy were significantly lower with respect to the other groups. Conclusions: These results suggest that an alteration of cerebrovascular reactivity may be responsible for reduction in some cognitive abilities involving the function of the hemisphere ipsilateral to carotid stenosis. Such findings may be of interest for providing a more comprehensive indication to surgical treatment in subgroups of subjects with asymptomatic carotid stenosis.
Abbreviations: BHI = breath-holding index; CVR = cerebrovascular reactivity; LCS/pCVR= subjects with left carotid stenosis and preserved cerebrovascular reactivity; LCS/rCVR = subjects with left carotid stenosis and reduced cerebrovascular reactivity; RCS/pCVR = subjects with right carotid stenosis and preserved cerebrovascular reactivity; RCS/rCVR = subjects with right carotid stenosis and reduced cerebrovascular reactivity; MMSE = Mini-Mental State Examination; MFV = mean flow velocity.
Disclosure: The authors report no disclosures. Received July 19, 2008. Accepted in final form November 21, 2008.
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