Objective To investigate the predictive value of the superb microvascular imaging(SMI)grading of carotid plaque combined with serum soluble intercellular adhesion molecule 1(sICAM-1)and cystatin C(CysC)in progressive ischemic stroke(PIS).Methods It was a retrospective analysis involving 216 acute ischemic stroke patients with carotid artery plaques admitted to the Neurology Department of Qinghai Red Cross Hospital from March 2020 to November 2022.They were divided into PIS group(66 cases)and non-PIS group(NPIS,150 cases).Logistic regression was used to analyze the independent risk factors for PIS.Receiver operating characteristic(ROC)curve was used to analyze the diagnostic value of the SMI grading of carotid plaque combined with serum sICAM-1 and CysC in PIS.Results Compared with those of the NPIS group,patients in the PIS group had significantly higher homocysteine(Hcy),fibrinogen(FIB),sICAM-1 and CysC levels,and the National Institutes of Health Stroke Scale(NIHSS)scores on admission(P<0.05).There was a significant difference in the SMI grading of carotid plaque between PIS group and NPIS group(P<0.05).Logistic regression analysis found that the NIHSS score,sICAM-1,CysC,and SMI grading of carotid plaque on admission were independent risk factors for PIS(P<0.05).ROC curve analysis showed that the area under the curve(AUC)of the SMI grading of carotid plaque in diagnosing PIS was 0.842,and that of serum sICAM-1 and CysC levels was 0.803 and 0.802,respectively.The AUC of the SMI grading of carotid plaque combined with serum sICAM-1 and CysC in diagnosing PIS was 0.959.Conclusion Serum sICAM-1 and CysC levels are significantly elevated in PIS patients,and the SMI grading of carotid plaque combined with serum sICAM-1 and CysC can improve the performance in predicting PIS.