Polar transform network for prostate ultrasound segmentation with uncertainty estimation

•Prostate ultrasound volume segmentation from a new perspective by efficiently representing the prostate shape in the polar coordinate space with emphasis on the challenging base and apex regions.•A novel polar transform network (PTN) is proposed to implement polar transform for end-to-end deep learning based image segmentation with much fewer parameters, which achieves superior performance compared with state-of-the-art methods.•An innovative centroid perturbed test-time augmentation (CPTTA) strategy to refine the segmentation results and estimate uncertainty maps.