RÉSUMÉ
Objective To analyze the risk factors of cortical micro-infarcts (CMIs) in patients with acute ischemic stroke and to evaluate the diagnostic value of 3.0 Tesla (T) magnetic resonance imaging (MRI) using double inversion recovery (DIR) sequence and 3-dimensional fluid attenuated inversion recovery (3D-FLAIR) sequence in CMIs in vivo.Methods One hundred and ten consecutive patients with acute ischemic stroke within 7 d of onset were chosen from August 2014 to July 2015;these patients were classified into CMIs group and non-CMIs group by results of 3.0 conventional T MRI,DIR-MRI and 3D-FLAIR-MRI.Baseline characteristics and risk factors were analyzed to investigate the independent risk factors of CMIs.The presence of CMIs was evaluated based on conventional T MRI,DIR-MRI and 3D-FLAIR-MRI.Results Of the 110 enrolled patients with acute ischemic stroke,CMIs were presented in 23.6％ patients (26/110).The age of patients from the CMIs group was significantly older as compared with that of patients from the non-CMIs group (67.65±10.37 vs.58.52± 11.24 years old,P=0.009).Patients from the CMIs group had significantly higher percentages of age＞65 years,age of 76-80 years,hypertension,history of cerebral ischemia and intracranial atherosclerosis than patients from non-CMIs group (P＜0.05).Multivariate Logistic regression analysis indicated that age＞65 years (OR=1.982;95％CI:1.362-2.889,P=0.010) and hypertension (OR=1.326;95％CI:1.022-1.682,P=0.026) were the independent risk factors of CMIs.The prevalence of CMIs detected by conventional sequence (10.9％) was significantly lower than that detected by DIR sequence (23.6％) or 3D-FLAIR sequence (20.9％,P=0.013 and P=0.043).Conclusions Age＞65 years and hypertension are independent risk factors of CMIs.DIR and 3D-FLAIR sequences at 3.0 T MRI substantially improve the sensitivity of detection of CMIs as compared with conventional MRI sequence.