Value of superb micro-vascular imaging in predicting ischemic stroke in patients with carotid atherosclerotic plaques

BACKGROUND Unstable carotid atherosclerotic plaques are prone to cause ischemic stroke.Contrast-enhanced ultrasound(CEUS) is the primary method of assessing plaque stability, but CEUS cannot be a method for screening for unstable plaque. The emergence of superb micro-vascular imaging(SMI) offers the possibility of clinically screening for unstable plaque AIM To investigate the value of SMI in predicting ischemic stroke in patients with carotid atherosclerotic plaques.METHODS Patients with carotid atherosclerotic plaques(luminal stenosis of 50%-70%) were enrolled into the present study. All patients received conservative medication.The patient's clinical baseline data, serological data, CEUS and SMI data were analyzed. All patients underwent a 3-year follow-up. The follow-up endpoint was the occurrence of ischemic stroke and patients were divided into stroke group and non-stroke group according to whether the prognosis occurred or not.Subsequently, the difference in clinical data was compared, the correlation of SMI and CEUS was analyzed, and multiple Cox regression and receiver operating characteristic curve were applied to investigate the value of SMI and CEUS in predicting cerebral arterial thrombosis in three years.RESULTS In this study, 43 patients were enrolled in the stroke group and 82 patients were enrolled in the non-stroke group. Cox regression revealed that SMI level(P =0.013) and enhancement intensity(P = 0.032) were the independent factors influencing ischemic stroke. There was a positive correlation between SMI level and enhancement intensity(r = 0.737, P = 0.000). The area under curve of SMI level predicting ischemic stroke was 0.878. The best diagnostic point was ≥ level Ⅱ, and its sensitivity and specificity was 86.05% and 79.27%. The area under curve of enhancement intensity predicting ischemic stroke was 0.890. The best diagnostic point was 9.92 db, and its sensitivity and specificity was 88.37% and89.02%. As the SMI level gradually increased, the incidence of ischemic stroke increased gradually(X^2 = 108.931, P = 0.000).CONCLUSION SMI can be used as a non-invasive method of screening for unstable plaques and may help prevent ischemic stroke.