Adaptive Knowledge Transferring with Switching Dual-Student Framework for Semi-Supervised Medical Image Segmentation
Thanh-Huy Nguyen, Hoang-Thien Nguyen, Ba-Thinh Lam, Vi Vu, Bach X. Nguyen, Jianhua Xing, Tianyang Wang, Xingjian Li, Min Xu
TL;DR
This work tackles limitations of Mean-Teacher in semi-supervised medical image segmentation by introducing a switching Dual-Student framework with entropy-guided Student Selection and a Loss-Aware Exponential Moving Average (LA-EMA). The method uses Dual-Student Cross-Sample CutMix to diversify pseudo-labels, selects the most reliable student for teacher updates, and adaptively weights EMA updates based on student loss, all underpinned by PAC-Bayes-based reasoning. Empirical results on 3D medical datasets (LA and ACDC) and general datasets (CIFAR-10, Pascal VOC) show state-of-the-art accuracy and robust performance under limited supervision, with ablations confirming the effectiveness of CSC, SS, and LA-EMA. The approach offers a practical, plug-and-play improvement to semi-supervised segmentation pipelines with substantial impact for clinical imaging tasks where annotations are scarce.
Abstract
Teacher-student frameworks have emerged as a leading approach in semi-supervised medical image segmentation, demonstrating strong performance across various tasks. However, the learning effects are still limited by the strong correlation and unreliable knowledge transfer process between teacher and student networks. To overcome this limitation, we introduce a novel switching Dual-Student architecture that strategically selects the most reliable student at each iteration to enhance dual-student collaboration and prevent error reinforcement. We also introduce a strategy of Loss-Aware Exponential Moving Average to dynamically ensure that the teacher absorbs meaningful information from students, improving the quality of pseudo-labels. Our plug-and-play framework is extensively evaluated on 3D medical image segmentation datasets, where it outperforms state-of-the-art semi-supervised methods, demonstrating its effectiveness in improving segmentation accuracy under limited supervision.
