CAS-GAN for Contrast-free Angiography Synthesis
De-Xing Huang, Xiao-Hu Zhou, Mei-Jiang Gui, Xiao-Liang Xie, Shi-Qi Liu, Shuang-Yi Wang, Hao Li, Tian-Yu Xiang, Zeng-Guang Hou
TL;DR
CAS-GAN addresses the problem of reducing iodinated contrast in X-ray angiography by learning to synthesize angiographies from non-contrast X-rays. It introduces a disentangled latent space separating background and vessel components, coupled with a predictor that maps background representations to vessel representations, and a vessel semantic-guided generator with a corresponding semantic adversarial loss to improve vascular realism. The model optimizes a composite objective including prediction, image- and latent-cycle consistency, and reconstruction losses, achieving state-of-the-art FID ($5.87$) and MMD ($0.016$ in abstract/table, 0.16 reported) on the XCAD dataset and showing positive ablation and external validation results. This approach demonstrates strong potential for clinical use by providing high-fidelity, contrast-free angiography synthesis and guiding safer interventional procedures.
Abstract
Iodinated contrast agents are widely utilized in numerous interventional procedures, yet posing substantial health risks to patients. This paper presents CAS-GAN, a novel GAN framework that serves as a "virtual contrast agent" to synthesize X-ray angiographies via disentanglement representation learning and vessel semantic guidance, thereby reducing the reliance on iodinated contrast agents during interventional procedures. Specifically, our approach disentangles X-ray angiographies into background and vessel components, leveraging medical prior knowledge. A specialized predictor then learns to map the interrelationships between these components. Additionally, a vessel semantic-guided generator and a corresponding loss function are introduced to enhance the visual fidelity of generated images. Experimental results on the XCAD dataset demonstrate the state-of-the-art performance of our CAS-GAN, achieving a FID of 5.87 and a MMD of 0.016. These promising results highlight CAS-GAN's potential for clinical applications.
