PLOT-CT: Pre-log Voronoi Decomposition Assisted Generation for Low-dose CT Reconstruction

TL;DR

PLOT-CT introduces a novel pre-log Voronoi decomposition approach for low-dose CT reconstruction, effectively disentangling data components to improve noise robustness and reconstruction quality.

Contribution

The paper proposes a new Voronoi decomposition technique applied to pre-log sinograms, enhancing feature learning and noise mitigation in low-dose CT reconstruction.

Findings

Achieves 2.36dB PSNR improvement over traditional methods.

Effectively disentangles data components in the pre-log domain.

Enhances reconstruction accuracy in low-photon scenarios.

Abstract

Low-dose computed tomography (LDCT) reconstruction is fundamentally challenged by severe noise and compromised data fidelity under reduced radiation exposure. Most existing methods operate either in the image or post-log projection domain, which fails to fully exploit the rich structural information in pre-log measurements while being highly susceptible to noise. The requisite logarithmic transformation critically amplifies noise within these data, imposing exceptional demands on reconstruction precision. To overcome these challenges, we propose PLOT-CT, a novel framework for Pre-Log vOronoi decomposiTion-assisted CT generation. Our method begins by applying Voronoi decomposition to pre-log sinograms, disentangling the data into distinct underlying components, which are embedded in separate latent spaces. This explicit decomposition significantly enhances the model's capacity to learn discriminative features, directly improving reconstruction accuracy by mitigating noise and preserving information inherent in the pre-log domain. Extensive experiments demonstrate that PLOT-CT achieves state-of-the-art performance, attaining a 2.36dB PSNR improvement over traditional methods at the 1e4 incident photon level in the pre-log domain.