Parameter Decoupling Strategy for Semi-supervised 3D Left Atrium Segmentation

TL;DR

This paper introduces a semi-supervised 3D left atrium segmentation method using parameter decoupling to maintain diverse predictions and enhance generalization, outperforming existing approaches.

Contribution

The paper proposes a novel parameter decoupling strategy with a two-branch network to improve semi-supervised segmentation performance.

Findings

Achieved state-of-the-art results on the Atrial Segmentation Challenge dataset.

Demonstrated the effectiveness of parameter decoupling in semi-supervised learning.

Improved model generalization through alternating updates of feature extractor and classifiers.

Abstract

Consistency training has proven to be an advanced semi-supervised framework and achieved promising results in medical image segmentation tasks through enforcing an invariance of the predictions over different views of the inputs. However, with the iterative updating of model parameters, the models would tend to reach a coupled state and eventually lose the ability to exploit unlabeled data. To address the issue, we present a novel semi-supervised segmentation model based on parameter decoupling strategy to encourage consistent predictions from diverse views. Specifically, we first adopt a two-branch network to simultaneously produce predictions for each image. During the training process, we decouple the two prediction branch parameters by quadratic cosine distance to construct different views in latent space. Based on this, the feature extractor is constrained to encourage the consistency of probability maps generated by classifiers under diversified features. In the overall training process, the parameters of feature extractor and classifiers are updated alternately by consistency regularization operation and decoupling operation to gradually improve the generalization performance of the model. Our method has achieved a competitive result over the state-of-the-art semi-supervised methods on the Atrial Segmentation Challenge dataset, demonstrating the effectiveness of our framework. Code is available at https://github.com/BX0903/PDC.