Volumetric Conditional Score-based Residual Diffusion Model for PET/MR Denoising

TL;DR

This paper introduces a novel volumetric conditional score-based residual diffusion model tailored for PET/MR denoising, effectively handling 3D data to improve image quality while reducing computational costs.

Contribution

The proposed CSRD model uniquely incorporates a refined score function and 3D patch-wise training to enhance volumetric PET denoising and maintain anatomical consistency.

Findings

Achieves superior denoising performance compared to state-of-the-art methods.

Maintains spatial coherence and anatomical details in PET/MR images.

Reduces computational demands and speeds up the denoising process.

Abstract

PET imaging is a powerful modality offering quantitative assessments of molecular and physiological processes. The necessity for PET denoising arises from the intrinsic high noise levels in PET imaging, which can significantly hinder the accurate interpretation and quantitative analysis of the scans. With advances in deep learning techniques, diffusion model-based PET denoising techniques have shown remarkable performance improvement. However, these models often face limitations when applied to volumetric data. Additionally, many existing diffusion models do not adequately consider the unique characteristics of PET imaging, such as its 3D volumetric nature, leading to the potential loss of anatomic consistency. Our Conditional Score-based Residual Diffusion (CSRD) model addresses these issues by incorporating a refined score function and 3D patch-wise training strategy, optimizing the model for efficient volumetric PET denoising. The CSRD model significantly lowers computational demands and expedites the denoising process. By effectively integrating volumetric data from PET and MRI scans, the CSRD model maintains spatial coherence and anatomical detail. Lastly, we demonstrate that the CSRD model achieves superior denoising performance in both qualitative and quantitative evaluations while maintaining image details and outperforms existing state-of-the-art methods.