Loizou Christos P, Kyriacou Efthyvoulos, Griffin Maura B, Nicolaides Andrew N, Pattichis Constantinos S
IEEE Trans Ultrason Ferroelectr Freq Control. 2021 Sep;68(9):3017-3026. doi: 10.1109/TUFFC.2021.3081137. Epub 2021 Aug 27.
Recent studies have suggested that textural characteristics of the intima-media complex (IMC) may be more useful than the intima-media thickness (IMT) in evaluating cardiovascular risk. The primary aim of our study was to investigate the association between texture features of the common carotid IMC and prevalent clinical cardiovascular disease (CVD). The secondary aim was to determine whether IMT and IMC texture features vary between the left and right carotid arteries. The study was performed on 2208 longitudinal-section ultrasound images of the left (L) and right (R) common carotid artery (CCA), acquired from 569 men and 535 women out of which 125 had clinical CVD. L and R sides of the IMC were intensity normalized and despeckled. The IMC was semiautomatically delineated for all images using a semiautomated segmentation system, and 61 different texture features were extracted. The corresponding IMT semiautomated measurements (mean±SD) of the L and R sides were 0.73±0.21 mm/0.69±0.19 mm for the normal population and 0.83±0.17 mm/0.79±0.18 mm for those with CVD. IMC texture features did not differ between the right- and left-hand sides. Several texture features were independent predictors of the presence of CVD. The multivariate logistic regression analysis combining age, IMT, and texture features produced a receiver operating characteristic curve with an area under the curve of 89%. A correct classification rate of 77% for separating the normal subject (NOR) versus CVD subjects was achieved using the support vector machine classifier with a combination of clinical features, IMT, and extracted texture features. Texture features provide additional information on the presence of clinical CVD, which is over and above that provided by conventional risk factors or IMT alone. The value of IMC texture features in the prediction of future cardiovascular events should be tested in prospective studies.
最近的研究表明，在评估心血管风险方面，内膜-中膜复合体（IMC）的纹理特征可能比内膜-中膜厚度（IMT）更有用。我们研究的主要目的是调查颈总动脉IMC的纹理特征与临床心血管疾病（CVD）患病率之间的关联。次要目的是确定IMT和IMC纹理特征在左右颈动脉之间是否存在差异。该研究对569名男性和535名女性的2208张左、右颈总动脉（CCA）纵切面超声图像进行，其中125人患有临床CVD。对IMC的左右两侧进行强度归一化和去斑处理。使用半自动分割系统对所有图像半自动勾勒出IMC，并提取61种不同的纹理特征。正常人群左右两侧相应的IMT半自动测量值（均值±标准差）为0.73±0.21毫米/0.69±0.19毫米，患有CVD者为0.83±0.17毫米/0.79±0.18毫米。IMC纹理特征在左右两侧之间没有差异。几种纹理特征是CVD存在的独立预测因素。结合年龄、IMT和纹理特征的多变量逻辑回归分析产生了一条曲线下面积为89%的受试者工作特征曲线。使用支持向量机分类器结合临床特征、IMT和提取的纹理特征，区分正常受试者（NOR）和CVD受试者的正确分类率达到77%。纹理特征提供了关于临床CVD存在的额外信息，这超出了传统风险因素或单独的IMT所提供的信息。IMC纹理特征在预测未来心血管事件中的价值应在前瞻性研究中进行测试。
