Geometrically Constrained Stenosis Editing in Coronary Angiography via Entropic Optimal Transport
For medical imaging researchers and clinicians, this work improves automated stenosis detection by augmenting training data with geometrically controlled synthetic angiograms.
The paper addresses the scarcity of high-quality coronary angiography data for stenosis detection by proposing a diffusion-based editing method (OT-Bridge Editor) that uses entropic optimal transport and geometric constraints. The method achieves relative gains of 27.8% on the ARCADE benchmark and 23.0% on a multi-center dataset for downstream stenosis detection.
The scarcity of high-quality imaging data for coronary angiography (CAG) stenosis limits the clinical translation of automated stenosis detection. Synthetic stenosis data provides a practical avenue to augment training sets, improving data quality, diversity, and distributional coverage, and enhancing detection precision and generalization. However, diffusion-based editing commonly relies on soft guidance in a noise-initialized reverse process, offering limited pixel-level precision and structure preservation. We propose the OT-Bridge Editor, which reframes localized editing as a constrained entropic optimal transport (OT) problem and leverages geometric information to steer the generation path, enabling stronger geometric control. Extensive experiments show that our synthesized angiograms consistently improve downstream stenosis detection, yielding substantial relative gains of 27.8% on the public ARCADE benchmark and 23.0% on our multi-center dataset, supported by consistent qualitative results.