🤖 AI Summary
Accurate segmentation of tubular structures (e.g., vessels, airways) in medical images remains challenging due to multi-scale variations, complex topologies, and sparse annotations. To address these issues, we propose a robust segmentation framework featuring: (1) a deep-shallow feature fusion decoder to enhance multi-scale representation; (2) a vesselness-guided auxiliary alignment module that precisely couples shallow-level localization cues with deep-level semantic features; and (3) a growth-suppression balanced loss function jointly modeling topological priors and robustness to annotation noise. The framework further incorporates flexible-receptive-field convolutions and a context- and shape-aware loss for optimization. Evaluated on four public benchmarks, our method consistently outperforms state-of-the-art approaches in both 2D and 3D settings. Moreover, it demonstrates strong generalization capability on a private clinical dataset, confirming its practical applicability across diverse imaging domains and annotation regimes.
📝 Abstract
Accurate segmentation of tubular structures in medical images, such as vessels and airway trees, is crucial for computer-aided diagnosis, radiotherapy, and surgical planning. However, significant challenges exist in algorithm design when faced with diverse sizes, complex topologies, and (often) incomplete data annotation of these structures. We address these difficulties by proposing a new tubular structure segmentation framework named HarmonySeg. First, we design a deep-to-shallow decoder network featuring flexible convolution blocks with varying receptive fields, which enables the model to effectively adapt to tubular structures of different scales. Second, to highlight potential anatomical regions and improve the recall of small tubular structures, we incorporate vesselness maps as auxiliary information. These maps are aligned with image features through a shallow-and-deep fusion module, which simultaneously eliminates unreasonable candidates to maintain high precision. Finally, we introduce a topology-preserving loss function that leverages contextual and shape priors to balance the growth and suppression of tubular structures, which also allows the model to handle low-quality and incomplete annotations. Extensive quantitative experiments are conducted on four public datasets. The results show that our model can accurately segment 2D and 3D tubular structures and outperform existing state-of-the-art methods. External validation on a private dataset also demonstrates good generalizability.