Contrastive Learning Guided Fusion Network for Brain CT and MRI

Medical image fusion technology provides professionals with more detailed and precise diagnostic information. This paper introduces a new efficient CT and MRI fusion network, CLGFusion, based on a contrastive learning-guided network. CLGFusion includes two encoding branches at the feature encoding stage, enabling them to interact and learn from each other. The approach begins with training a single-view encoder to predict the feature representation of an image from varied augmented views. Simultaneously, the multi-view encoder is improved using the exponential moving average of the single-view encoder. Contrastive learning is integrated into medical image fusion by creating a feature contrast space without constructing negative samples. This feature contrast space cleverly uses the information of the difference in the feature product of the source image and its corresponding augmented image. It continuously guides the network to constantly optimize its fusion effect by combining the method of structural similarity loss, to achieve more accurate and efficient image fusion. This approach represents an end-to-end unsupervised fusion model. Experimental validation shows that our proposed method demonstrates performance comparable to state-of-the-art techniques in both subjective evaluation and objective metrics.