Abstract: Objective To investigate the application value of carotid plaque superb micro-vascular imaging (SMI) classification combined with serum hypersensitive C-reactive protein (hs-CRP) in risk assessment of acute ischemic stroke(AIS). 
Methods A total of 156 patients with carotid plaque in the Department of Neurology of our hospital were included. According to MRI examination results and the clinical diagnosis, they were divided into AIS group (n=72) and non-AIS group (n=84). All the patients underwent routine carotid ultrasonography examination and SMI examination, and serum hs-CRP level was measured. Based on logistic regression model and receiver operating characteristic(ROC) curve, SMI classification of neovascularization in plaque and serum hs-CRP alone or in combination were analyzed to predict the risk of AIS, and its cut-off value was determined. 
Results There was significant difference in SMI classification between two groups (P＜0.05). The level of serum hs-CRP in AIS group was significantly higher than that in NAIS group (P＜0.05). There was no significant difference in plaque thickness and area stenosis rate between two groups (both P＞0.05). SMI classification(OR=4.015, 95%CI: 2.426-6.646, P＜0.001) and serum hs-CRP (OR=1.809, 95%CI: 1.313-2.498, P＜0.001) were independent risk factors for the occurrence of AIS(both P＜0.05). Taking SMI classification≥2 as the diagnostic standard for predicting the occurrence of AIS, the area under ROC curve (AUC) was 0.787, and the sensitivity and specificity were 81.97% and 66.66% respectively. Taking serum hs-CRP ≥ 4.7 mg/L as the diagnostic standard for predicting the occurrence of AIS, the AUC was 0.699, and the sensitivity and specificity were 66.67% and 65.48% respectively. The AUC of the combined diagnosis for predicting the occurrence of AIS was 0.842, and the sensitivity and specificity were 90.28% and 66.67% respectively. 
Conclusion  Carotid plaque SMI classification combined with serum hs-CRP can improve the accuracy of predicting the risk of AIS.

Key words: ischemic stroke, carotid stenosis, C-reactive protein