Abstract: The examination of the lung is a requisite part of the medical examination. There are quantities of cases in the medical examination, and each case contains plenty of cross-sectional CT images of the lung. While, all of these requires that professional doctors screen out the cases of lung nodules one by one, which not only cause tons of work, but also a possibility of inaccurate screening. Aiming at above problems, the Convolutional Neural Network（CNN） is introduced to screen out the CT images of lung nodules, and a classification algorithm based on CNN is proposed. The experimental results on the LIDC database show that, comparing with the widely used lenet-5 networks and traditional methods, the accuracy of classification is increased by 4 to 10 points by using self-defined convolutional neural network. AUC is 0.821?6, which is the largest of several classifiers. In brief, this method can distinguish CT images of the lung more accurately than other methods, and provides more objective reference for clinical diagnosis.

Key words: pulmonary nodule, classification algorithm, image segmentation, Convolutional Neural Network, deep learning

摘要： 肺部的检查是每年体检的重要一部分。体检中有成百上千的病例，而每个病例中含有许多的肺部横切面CT图像。这些都需要专业医生去逐个筛查出存在肺结节的病例，不仅工作量大而且存在误筛的可能。针对上述问题，把卷积神经网络（CNN）引入筛查存在肺结节的CT图像诊断，提出一种基于CNN的分类算法。在LIDC数据库的实验结果表明，对比应用广泛的lenet-5网络和传统方法等，使用自定义的卷积神经网络将分类的正确率提升了4到10个百分点不等。AUC值为0.821?6，也是几个分类器中最大的。相比于其他方法，该方法能较为准确地识别肺部CT图像，可以为临床诊断提供较为客观的参考。

关键词: 肺结节, 分类算法, 图像分割, 卷积神经网络, 深度学习