Besides per-pixel accuracy, topological correctness is also crucial for the segmentation of images with fine-scale structures, e.g., satellite images and biomedical images. In this paper, by leveraging the theory of digital topology, we identify pixels in an image that are critical for topology. By focusing on these critical pixels, we propose a new homotopy warping loss to train deep image segmentation networks for better topological accuracy. To efficiently identify these topologically critical pixels, we propose a new algorithm exploiting the distance transform. The proposed algorithm, as well as the loss function, naturally generalize to different topological structures in both 2D and 3D settings. The proposed loss function helps deep nets achieve better performance in terms of topology-aware metrics, outperforming state-of-the-art structure/topology-aware segmentation methods. 
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                            A Topological-Attention ConvLSTM Network and Its Application to EM Images
                        
                    
    
            Structural accuracy of segmentation is important for fine-scale structures in biomedical images. We propose a novel Topological-Attention ConvLSTM Network (TACLNet) for 3D anisotropic image segmentation with high structural accuracy. We adopt ConvLSTM to leverage contextual information from adjacent slices while achieving high efficiency. We propose a Spatial Topological-Attention (STA) module to effectively transfer topologically critical information across slices. Furthermore, we propose an Iterative Topological-Attention (ITA) module that provides a more stable topologically critical map for segmentation. Quantitative and qualitative results show that our proposed method outperforms various baselines in terms of topology-aware evaluation metrics. 
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                            - Award ID(s):
- 1909038
- PAR ID:
- 10355442
- Date Published:
- Journal Name:
- Medical Image Computing and Computer Assisted Intervention (MICCAI)
- Page Range / eLocation ID:
- 217 - 228
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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