Cerebrovascular Reserve may be a More Accurate Predictor of Stroke than Degree of ICA or MCA Stenosis
Mingyong Liu, Lichun Zhou
Department of Neurology, Capital Medical University Chaoyang Hospital, Beijing, China (mainland)
Med Sci Monit 2014; 20:2082-2087
It is currently unclear whether the degree of stenosis or the cerebrovascular reserve (CVR) is a better predictor of ischemic stroke.
Material and Methods: In this study, CVR was measured by perfusion computed tomography with inhalation of 5% CO2 in 37 symptomatic patients with internal carotid artery (ICA) or middle cerebral artery (MCA) stenosis or occlusion. Patients were divided into groups according to the degree of stenosis: ≥70% stenosis (stenosis group 1) or <70% stenosis (stenosis group 2); and according to CVR: ≥10% CVR (CVR group 1) or <10% CVR (CVR group 2). All patients were given medical treatment.
Results: During a mean follow-up period of 56.9 months (range 24–73 months), recurrent ipsilateral ischemic stroke occurred in 7 patients. Ischemic stroke occurred in 0 of 19 patients in CVR group 1 (annual risk 0%), 7 of 18 patients in CVR group 2 (annual risk 7.7%), 3 of 18 patients in stenosis group 1 (annual risk 3.3%), and 4 of 19 patients in stenosis group 2 (annual risk 4.7%). Comparisons using Pearson’s chi-square test showed a significant difference in the rate of ischemic stroke between CVR group 1 and CVR group 2 (odds ratio 1.700; 95% confidence interval 1.142–2.530; P=0.003), but no significant difference between stenosis group 1 and stenosis group 2 (P=0.691).
Conclusions: Cerebrovascular reserve may be a more accurate predictor of stroke than degree of ICA or MCA stenosis
Keywords: Adult, Aged, 80 and over, Brain - physiopathology, Constriction, Pathologic - physiopathology, Middle Cerebral Artery - pathology, Recurrence, Stroke - physiopathology