Two-Phase Multi-Dose-Level PET Image Reconstruction with Dose Level Awareness
This work addresses the challenge of minimizing radiation exposure in PET imaging by improving reconstruction quality across multiple dose levels, representing an incremental advance in medical imaging methods.
The paper tackles the problem of reconstructing high-quality standard-dose PET images from low-dose PET images with varying dose levels, proposing a two-phase algorithm with dose level awareness that achieves superior performance on a benchmark dataset.
To obtain high-quality positron emission tomography (PET) while minimizing radiation exposure, a range of methods have been designed to reconstruct standard-dose PET (SPET) from corresponding low-dose PET (LPET) images. However, most current methods merely learn the mapping between single-dose-level LPET and SPET images, but omit the dose disparity of LPET images in clinical scenarios. In this paper, to reconstruct high-quality SPET images from multi-dose-level LPET images, we design a novel two-phase multi-dose-level PET reconstruction algorithm with dose level awareness, containing a pre-training phase and a SPET prediction phase. Specifically, the pre-training phase is devised to explore both fine-grained discriminative features and effective semantic representation. The SPET prediction phase adopts a coarse prediction network utilizing pre-learned dose level prior to generate preliminary result, and a refinement network to precisely preserve the details. Experiments on MICCAI 2022 Ultra-low Dose PET Imaging Challenge Dataset have demonstrated the superiority of our method.