Self-supervised contrastive learning technique for classifying carotid plaques from ultrasound images under label scarcity. In a pretext task, a triplet network takes three augmented views (strong- and weak-augmentation) of each image and promotes their similarity from both feature- and instance-level perspectives to learn effective plaque representations; the resulting encoder is then fine-tuned on labeled ultrasound images for the downstream classification task. FeaCL achieved 83.4% classification accuracy using only 30% of the training data -- a 16.3% improvement over the same network trained without the self-supervised pretext task.

Deep learning model for multi-class 3D segmentation of the aorta and its thirteen branches from CT angiography, intended to support planning of endovascular aortic interventions. CIS-UNet combines a CNN encoder with a symmetric decoder and a novel Context-aware Shifted Window Self-Attention (CSW-SA) bottleneck block that adapts the Swin transformer's patch-merging mechanism to more efficiently capture global spatial context. Trained and evaluated via 4-fold cross-validation on the first public multi-branch aorta CTA dataset (59 patients), CIS-UNet outperformed the state-of-the-art SwinUNETR baseline, achieving a mean Dice of 0.713 vs. 0.697 and mean surface distance of 2.78mm vs. 3.39mm, while being more computationally efficient.

Self-supervised learning method for carotid plaque segmentation from B-mode ultrasound images, designed to reduce the amount of expert-labeled data needed to train a segmentation network. A level-set-and-least-squares-based deformation procedure synthesizes registration image pairs from unlabeled carotid ultrasound images, and a spatial-transformer-based registration pretext task pretrains a Stacked U-Net (Su-Net) to focus on plaque-contour features before fine-tuning on a small labeled dataset for total plaque area (TPA) segmentation. Evaluated on carotid ultrasound datasets from two different institutions and countries, the method showed robust generalization when trained with only a small number of labeled images.