Sg-moe-net: semantic-guided mixture of experts with cross-modality attention for 3D medical segmentation
摘要
Multimodal 3D medical image segmentation remains challenging due to feature misalignment caused by intrinsic differences among imaging modalities. To address this issue, we propose the Semantic-Guided Mixture-of-Experts Network (SG-MoE-Net), a modality-aware framework built upon SwinUNETR. The proposed model incorporates a modality-decoupled Mixture-of-Experts architecture, in which heterogeneous experts are selectively activated to process CT, MRI, and semantic representations, thereby reducing cross-modality interference. Furthermore, a cross-level semantic guidance mechanism is introduced to integrate anatomical priors and promote semantic consistency across modalities during feature learning. Extensive experiments on three public multimodal benchmarks, namely CrossMoDA, MM-WHS, and HaN-Seg, demonstrate that SG-MoE-Net consistently outperforms existing state-of-the-art methods. In particular, the proposed approach achieves a Dice score of 84.3% on the CrossMoDA dataset. On the HaN-Seg benchmark, it attains a Dice score of 86.2%, outperforming existing state-of-the-art methods by 1.0% in Dice and 1.4% in Normalized Surface Dice.