Automatic Segmentation of Covid-19 Infected Regions in Chest CT Images Based on 2D/3D Model Ensembling
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摘要: 自2019年末以来, 全球蔓延的新型冠状病毒(Coronavirus disease 2019, Covid-19)已经给世界人民造成了严重的健康威胁. 其中新型冠状病毒患者的计算机断层扫描(Computer tomography, CT)图像通过肺炎病灶分割技术可以为医学诊断提供有价值的量化信息. 虽然目前基于深度学习的方法已经在新型冠状病毒肺炎病灶分割任务上取得了良好的效果, 但是在面对不同中心数据的情况下分割效果往往会大幅下降. 因此, 研究一种具有更好泛化性能的新型冠状病毒肺炎病灶分割算法具有重要意义. 提出一种新冠肺炎病灶多模型融合分割方法. 通过训练3DUnet模型和2DUnet结合方向场(Direction field, DF)模型, 利用多种模型各自优点进行分割结果的融合, 得到更好的泛化性能. 通过同中心和跨中心数据集的实验, 证明该方法能够有效提高新冠肺炎病灶分割的泛化性能, 为医学诊断分析提供帮助.
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关键词:
- 新冠肺炎 /
- 计算机断层扫描影像分割 /
- 深度学习 /
- 泛化性能
Abstract: Currently, the global pandemic of coronavirus disease 2019 (Covid-19) causes serious health risks. The coronavirus disease computer tomography (CT) image pneumonia lesion segmentation can provide quantitative information and greatly help for the diagnosis. Although existing deep learning-based methods have achieved good performance on coronavirus disease pneumonia lesion segmentation, the performance usually drops a lot while meeting different center datasets, which is especially common in the coronavirus disease global pandemic. Therefore, it is of great interest to propose an algorithm with better generalization performance for coronavirus disease pneumonia lesion segmentation. In this paper, we present a novel method to fuse multi-models for improving the generalization performance of lesion segmentation. Specifically, we train the 3DUnet and the 2DUnet combined with direction field (2DUnetDF). Then, we fuse 2D and 3D segmentation results to make a better generalization result with the advantage of different models. The in-dataset and cross-dataset experiments show that our method can significantly improve the generalization performance and provide effective help for doctors to analyze the CT images of patients in actual clinical usage.-
Key words:
- Covid-19 /
- CT segmnetation /
- deep learning /
- generalizability
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表 1 XH150训练在XH40和TJ40测试的Dice结果
Table 1 Dice comparison of methods trained on XH150 and test on XH40 and TJ40 datasets
方法 XH40 TJ40 3DUnet 80.93 77.95 2DUnet 86.94 74.64 3D + 2DUnet (FMM) 87.57 81.90 3D + 2DUnetDF (FMM) 87.93 82.90 表 2 TJ145训练在XH40和TJ40测试的Dice结果
Table 2 Dice comparison of methods trained on TJ145 and test on XH40 and TJ40 datasets
方法 XH40 TJ40 3DUnet 70.17 79.81 2DUnet 78.25 87.08 3D + 2DUnet (FMM) 80.93 87.52 3D + 2DUnetDF (FMM) 82.43 87.62 表 3 不同方法在同数据集测试的Hausdorff95结果
Table 3 In-dataset evaluation of different methods for Hausdorff95
Method XH40 TJ40 3DUnet 4.03 5.59 2DUnet 2.73 4.17 3D + 2DUnet (FMM) 2.74 4.19 3D + 2DUnetDF (FMM) 2.72 4.24 表 4 不同方法在交叉数据集测试的Hausdorff95结果
Table 4 Cross-dataset evaluation of different methods for Hausdorff95
方法 XH40 TJ40 3DUnet 5.39 5.69 2DUnet 3.46 4.68 3D + 2DUnet (FMM) 3.38 4.48 3D + 2DUnetDF (FMM) 3.23 4.46 表 5 XH150训练, 不同融合方法在XH40和TJ40测试Dice的对比结果
Table 5 Dice comparison of methods trained on XH150 test on XH40 and TJ40 datasets with different fusion methods
方法 XH40 TJ40 3DUnet 80.93 77.95 3DUnet-Voting 81.55 79.10 2DUnet 86.94 74.64 2DUnet-Voting 86.81 72.49 3D + 2DUne (FMM) 87.57 81.90 Multi3D2DUnet-Voting 85.05 74.35 Multi3D2DUnet-Voting (FMM) 88.19 82.36 表 6 TJ145训练, 不同融合方法在XH40和TJ40测试Dice的对比结果
Table 6 Dice comparison of methods trained on TJ145 test on XH40 and TJ40 datasets with different fusion methods
方法 XH40 TJ40 3DUnet 70.17 79.81 3DUnet-Voting 73.88 80.54 2DUnet 78.25 87.08 2DUnet-Voting 80.94 87.16 3D + 2DUnet (FMM) 80.93 87.52 Multi3D2DUnet-Voting 82.51 86.73 Multi3D2DUnet-Voting (FMM) 85.48 87.48 表 7 XH150训练在XH40和TJ40上测试的消融实验结果
Table 7 Ablation studies for Dice trained on XH150 test on XH40 and TJ40 datasets
方法 XH40 TJ40 3DUnet 80.93 77.95 2DUnet 86.94 74.64 2DUnetDF 87.83 76.84 3D + 2DUnet (FMM) 87.57 81.90 3D + 2DUnetDF (FMM) 87.93 82.90 表 8 TJ145训练在XH40和TJ40上测试的消融实验结果
Table 8 Ablation studies for Dice trained on TJ145 test on XH40 and TJ40 datasets
方法 XH40 TJ40 3DUnet 70.17 79.81 2DUnet 78.25 87.08 2DUnetDF 80.52 87.57 3D + 2DUnet (FMM) 80.93 87.52 3D + 2DUnetDF (FMM) 82.43 87.62 -
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