Out-of-Distribution Detection in Medical Image Segmentation with \(\beta \)-VAE and Likelihood Regret
摘要
The performance of deep learning models can be compromised in the presence of Out-of-Distribution (OOD) data, i.e., data which deviates from the training distribution, the IN-distribution. This work examines OOD detection for medical image segmentation, introducing a new method that simultaneously detects which image samples are OOD, but also finds if the segmentation masks are OOD. The latter problem may arise if there are corruptions or discrepancies in the ground truth annotation masks, a likely scenario in real-world medical imaging applications, which has not received research attention to date. Most works focus on sample-wise OOD detection, finding samples that do not follow the IN-distribution, or pixel-wise OOD detection, which finds pixels that do not follow the IN distribution (anomaly detection), but do not examine if the segmentation mask itself is OOD. We propose a new model for simultaneous OOD detection in image samples and annotations, based on a combination of