MedCL: Learning Consistent Anatomy Distribution for Scribble-supervised Medical Image Segmentation
This work addresses the challenge of reducing annotation costs for medical image segmentation, particularly for rare diseases, though it is incremental as it builds on existing weak supervision methods.
The paper tackles the problem of expensive full annotation for medical image segmentation by proposing MedCL, a scribble-supervised clustering framework that learns anatomy distribution priors, achieving substantial performance improvements on regular organs and irregular pathologies with less scribble supervision.
Curating large-scale fully annotated datasets is expensive, laborious, and cumbersome, especially for medical images. Several methods have been proposed in the literature that make use of weak annotations in the form of scribbles. However, these approaches require large amounts of scribble annotations, and are only applied to the segmentation of regular organs, which are often unavailable for the disease species that fall in the long-tailed distribution. Motivated by the fact that the medical labels have anatomy distribution priors, we propose a scribble-supervised clustering-based framework, called MedCL, to learn the inherent anatomy distribution of medical labels. Our approach consists of two steps: i) Mix the features with intra- and inter-image mix operations, and ii) Perform feature clustering and regularize the anatomy distribution at both local and global levels. Combined with a small amount of weak supervision, the proposed MedCL is able to segment both regular organs and challenging irregular pathologies. We implement MedCL based on SAM and UNet backbones, and evaluate the performance on three open datasets of regular structure (MSCMRseg), multiple organs (BTCV) and irregular pathology (MyoPS). It is shown that even with less scribble supervision, MedCL substantially outperforms the conventional segmentation methods. Our code is available at https://github.com/BWGZK/MedCL.