Neovascularization in carotid atherosclerotic plaques can be effectively evaluated by superb microvascular imaging (SMI): Initial experience
Xuanjia Chen, Hongyan Wang, Yuxin Jiang, Jianchu Li, Na Li, Jing Kong, Xiaoyan Zhang, Wei Ye, Dachun Zhao, Siman Cai
Abstract
The objective of this study was to investigate the correlation between the amount of blood flow in the area of neovascularization within a carotid atherosclerotic plaque by superb microvascular imaging (SMI) and the microvessel density (MVD) determined by histopathological staining. Twenty-eight carotid atherosclerotic plaques were detected by SMI in 28 patients who underwent carotid endarterectomy. SMI was graded according to the visual methods as follows: grade I: no appearance of neovascularization within the plaque; grade II: punctate neovascularization; grade III: one or two linear neovascularizations within the plaque; and grade IV: multiple (> 2) linear neovascularizations throughout the plaque. The neovascularization density was determined by the CD31 complex staining method. There was a significant correlation between the density of neovascularization in histopathologic plaques and the blood flow grade found by SMI ( r = 0.788, p < 0.001). A significant difference was observed in SMI blood flow grade between the symptomatic and asymptomatic groups (χ 2 = 2.634, p = 0.036). The MVD of plaques in the symptomatic group was significantly higher than that in the asymptomatic group ( t = 2.530, p = 0.018). The SMI-based classification was positively correlated with plaque thickness. SMI, which is a new nonultrasound contrast-enhanced imaging method, can effectively evaluate neovascularization in carotid atherosclerotic plaques and can be used as a novel method for the clinical prediction of stroke risk.