The data-driven nature of deep learning models for semantic segmentation requires a large number of pixel-level annotations. However, large-scale and fully labeled medical datasets are often unavailable for practical tasks. Recently, partially supervised methods have been proposed to utilize images with incomplete labels to mitigate the data scarcity problem in the medical domain. As an emerging research area, the breakthroughs made by existing methods rely on either large-scale data or complex model design, which makes them 1) less practical for certain real-life tasks and 2) less robust for small-scale data. It is time to step back and think about the robustness of partially supervised methods and how to maximally utilize small-scale and partially labeled data for medical image segmentation tasks. To bridge the methodological gaps in label-efficient deep learning with partial supervision, we propose RAMP, a simple yet efficient data augmentation framework for partially supervised medical image segmentation by exploiting the assumption that patients share anatomical similarities. We systematically evaluate RAMP and the previous methods in various controlled multi-structure segmentation tasks. Compared to the mainstream approaches, RAMP consistently improves the performance of traditional segmentation networks on small-scale partially labeled data and utilize additional image-wise weak annotations.
Download