🤖 AI Summary
Existing abdominal CT segmentation datasets suffer from limited scale, coarse-grained annotations, and single-center bias, hindering transfer learning and fair algorithm benchmarking. To address this, we introduce AbdomenAtlas—the first large-scale, multi-center abdominal CT dataset featuring dual-level (organ and lesion) fine-grained 3D pixel-wise annotations across 7 hospitals and 5 scanning protocols, covering 33 anatomical structures and pathologies. We propose a semi-automatic annotation paradigm integrating weakly supervised pre-labeling, expert-guided 3D interactive refinement, standardized DICOM preprocessing, and privacy-preserving de-identification. Evaluated on eight downstream tasks, models trained on AbdomenAtlas achieve an average 4.2% mDice improvement and 37% higher few-shot transfer stability. The dataset is publicly released and adopted as the official MICCAI 2024 benchmark.