Accurate vascular segmentation is essential for coronary visualization and the diagnosis of coronary heart disease. This task involves the extraction of sparse tree-like vascular branches from volumetric space. However, existing methods have faced significant challenges due to discontinuous vascular segmentation and missing endpoints. To address this issue, a 3D vision graph neural network framework, named ViG3D-UNet, was introduced. This method integrates 3D graph representation and aggregation within a U-shaped architecture to facilitate continuous vascular segmentation. The ViG3D module captures volumetric vascular connectivity and topology, while the convolutional module extracts fine vascular details. These two branches are combined through channel attention to form the encoder feature. Subsequently, a paperclip-shaped offset decoder minimizes redundant computations in the sparse feature space and restores the feature map size to match the original input dimensions. To evaluate the effectiveness of the proposed approach for continuous vascular segmentation, evaluations were performed on two public datasets, ASOCA and ImageCAS. The segmentation results show that the ViG3D-UNet surpassed competing methods in maintaining vascular segmentation connectivity while achieving high segmentation accuracy.

Efficient feature learning is considered indispensable for maximizing the representation of scarce information in tiny datasets. However, existing methods are often unable to fully exploit local features and contextual dependencies when dealing with tiny datasets. To overcome this shortcoming, a Cross-Feature Vision Transformer (CF-ViT) was proposed, which decouples local feature refinement from global context modeling and leverages the complementary strengths of CNNs and Transformers. Specifically, a Cross-Scale Fusion (CSF) module was introduced to integrate features from multiple scales, ensuring that cross-scale information is globally embedded. In addition, a Feature Enhancement and Reorganization (FER) module was incorporated into CF-ViT, whereby Transformer outputs are reorganized into 2D feature maps for convolution-based detail enhancement to thoroughly exploit local information. Extensive experiments have demonstrated that CF-ViT consistently surpasses baselines across 4 tiny datasets, reaching a 96.87% (KSDD) Top-1 accuracy with only 29.19 million parameters and 2.67 billion FLOPs. Moreover, a Top-1 accuracy of 85.03% is attained on a real-world tiny dataset of wood surface defect detection, exceeding all baselines. These findings underscore the effectiveness and generalization capability of CF-ViT in capturing fine-grained local details and global context, offering a promising and deployable solution for vision tasks in tiny datasets.

Vision transformers have achieved remarkable success in image classification. The dual-branch vision transformer generates more features by taking advantage of feature fusion. Inspired by this, a dual-branch vision transformer with Real-Time Share feature was proposed during the encoding process for retinal image classification tasks. The approach processes image patches of varying sizes (base and large) through two independent branches and implements multi-stage Real-Time feature fusion via the Real-Time Share feature encoder. This encoder enables the branches to complement each other's features at each encoding stage, facilitating finer feature learning and enhancing the self-attention information passed to subsequent stages. It significantly boosts feature representation and classification performance. Additionally, a straightforward and effective feature fusion method, L-Times Attention Fusion, was proposed: vector concatenation for Real-Time Share feature in the earlier (L-1) encoding stages and element-wise addition for overall feature fusion at the L-th stage, achieving more efficient feature integration. The method was validated on a retinal image dataset. Results show that the approach outperforms the recent Cross-ViT average TOP-1 Acc by 5.61% with lower FLOPs and model parameters, without relying on pre-trained weights, highlighting stronger self-learning feature capabilities and reduced reliance on extensive pre-training data.

Lesion segmentation plays a crucial role in various medical image analyses, which not only improves the efficiency in clinical diagnosis but also assists in detecting early symptoms of various diseases. Most existing studies focus on directly extracting lesion information from specific types of medical images with pre-trained weights, often neglecting the underlying topological and pathological causes which lead to these lesions. Furthermore, they overlook to capture general anatomical features among lesions, which are related to the distribution of lesions, and thus the model is poorly generalized in different medical datasets. Inspired by these insights, we propose a Triple Fusion Net (TF-Net), a network structure divided into three branches: left, middle and right. The left and right branches are designed to extract lesion features and associated topological style features within various medical images, respectively. And these features are further fused and modeled in the middle branch. The proposed structure of triple branches for features fusing effectively learns multi-feature information and improves the performance of TF-Net. And our work experiments validate various feature fusion methods in the middle branch, including channel-wise concatenation, element-wise addition, attention gate, and transformer encoder block. Without using pre-trained weights in our network, the transformer encoder block performs best on some tasks of DDR and surpasses other pre-trained models. Channel concatenation exhibits performance close to other pre-trained models in both the IDRiD, Kvasir-Seg and TN3K. Attention gate fusion also shows competitive results in thyroid ultrasound segmentation. Our approach, leveraging a unique network structure and four different feature fusion methods, demonstrates remarkable generality across a spectrum of medical image segmentation tasks.

Peripheral waveform analysis (PWA), which is generally used to reveal hidden health status information from peripheral pulse signals, typically involves three procedures: signal preprocessing, feature extraction, and pattern classification. With the advancement of data-driven deep neural network methodologies, feature extraction and pattern classification have progressively converged into end-to-end neural networks, where the final layer of the network is equivalent to conventional pattern classifiers. However, the performance of deep learning models heavily relies on the quality of the dataset, rendering data signal preprocessing a crucial component. This study proposes a framework that integrates signal preprocessing, feature extraction, and pattern classification into a unified learning approach using heuristic algorithms, enabling the automatic discovery of optimal data encoding methods and their corresponding models. Initially, the search space is defined based on parameters relevant to signal preprocessing, and a fitness function is constructed utilizing CNN. Subsequently, the optimal combination of data preprocessing and CNN is determined through the heuristic algorithm Particle Swarm Optimization (PSO). The proposed method was evaluated in the dataset comprising authentic clinical cases of type 2 diabetes screening involving approximately 200 volunteers. The model derived from this framework demonstrates the capability to effectively discriminate between healthy volunteers and those with diabetes, achieving the highest accuracy of 93.6%. Compared to state-of-the-art algorithms, the proposed model was shown to be competitive in both accuracy and time cost.