51. Spectral CT Two-step and One-step Material Decomposition using Diffusion Posterior Sampling
- Author
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Vazia, Corentin, Bousse, Alexandre, Froment, Jacques, Vedel, Béatrice, Vermet, Franck, Wang, Zhihan, Dassow, Thore, Tasu, Jean-Pierre, and Visvikis, Dimitris
- Subjects
Physics - Medical Physics - Abstract
This paper proposes a novel approach to spectral computed tomography (CT) material decomposition that uses the recent advances in generative diffusion models (DMs) for inverse problems. Spectral CT and more particularly photon-counting CT (PCCT) can perform transmission measurements at different energy levels which can be used for material decomposition. It is an ill-posed inverse problem and therefore requires regularization. DMs are a class of generative model that can be used to solve inverse problems via diffusion posterior sampling (DPS). In this paper we adapt DPS for material decomposition in a PCCT setting. We propose two approaches, namely Two-step Diffusion Posterior Sampling (TDPS) and One-step Diffusion Posterior Sampling (ODPS). Early results from an experiment with simulated low-dose PCCT suggest that DPSs have the potential to outperform state-of-the-art model-based iterative reconstruction (MBIR). Moreover, our results indicate that TDPS produces material images with better peak signal-to-noise ratio (PSNR) than images produced with ODPS with similar structural similarity (SSIM)., Comment: 5 pages, 3 figures, submitted to EUSIPCO 2024
- Published
- 2024