Wang Linlin, Shen Lu, Shi Jun, Fei Xiaoyan, Zhou Weijun, Xu Haoyu, Liu Lizhuang
Shanghai Institute for Advanced Communication and Data Science, School of Communication and Information Engineering, Shanghai University, Shanghai 200444, P.R. China.
Department of Ultrasound, the First Affiliated Hospital of Anhui Medical University, Hefei 230022, P.R. China.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2021 Feb 25;38(1):30-38. doi: 10.7507/1001-5515.202002004.
Both feature representation and classifier performance are important factors that determine the performance of computer-aided diagnosis (CAD) systems. In order to improve the performance of ultrasound-based CAD for breast cancers, a novel multiple empirical kernel mapping (MEKM) exclusivity regularized machine (ERM) ensemble classifier algorithm based on self-paced learning (SPL) is proposed, which simultaneously promotes the performance of both feature representation and the classifier. The proposed algorithm first generates multiple groups of features by MEKM to enhance the ability of feature representation, which also work as the kernel transform in multiple support vector machines embedded in ERM. The SPL strategy is then adopted to adaptively select samples from easy to hard so as to gradually train the ERM classifier model with improved performance. This algorithm is verified on a B-mode ultrasound dataset and an elastography ultrasound dataset, respectively. The results show that the classification accuracy, sensitivity and specificity on B-mode ultrasound are (86.36±6.45)%, (88.15±7.12)%, and (84.52±9.38)%, respectively, and the classification accuracy, sensitivity and specificity on elastography ultrasound are (85.97±3.75)%, (85.93±6.09)%, and (86.03±5.88)%, respectively. It indicates that the proposed algorithm can effectively improve the performance of ultrasound-based CAD for breast cancers with the potential for application.
特征表示和分类器性能都是决定计算机辅助诊断(CAD)系统性能的重要因素。为了提高基于超声的乳腺癌CAD性能,提出了一种基于自步学习(SPL)的新型多经验核映射(MEKM)排他正则化机器(ERM)集成分类器算法,该算法同时提升了特征表示和分类器的性能。所提算法首先通过MEKM生成多组特征以增强特征表示能力,这些特征也作为嵌入ERM的多个支持向量机中的核变换。然后采用SPL策略从易到难自适应选择样本,从而逐步训练性能得到提升的ERM分类器模型。该算法分别在B模式超声数据集和弹性成像超声数据集上进行了验证。结果表明,在B模式超声上的分类准确率、灵敏度和特异性分别为(86.36±6.45)%、(88.15±7.12)% 和(84.52±9.38)%,在弹性成像超声上的分类准确率、灵敏度和特异性分别为(85.97±3.75)%、(85.93±6.09)% 和(86.03±5.88)%。这表明所提算法能够有效提高基于超声的乳腺癌CAD性能,具有应用潜力。