Motivation: Arterial spin labeling (ASL) perfusion imaging outside the brain is challenging due to motion. Solution to this requires either changes to the acquisition, external hardware, or subject training. Goal(s): Develop retrospective motion correction to improve kidney perfusion and renal blood flow (RBF) maps from paced and free breathing ASL without modification to acquisition or external hardware. Approach: We choose a subset of the available ASL dynamics based on maximizing low-rank energy of the spatiotemporal dynamics. Results: he proposed motion correction framework increases cortex SNR in perfusion maps and increases corticomedullary RBF ratio on six subjects who performed paced breathing. Impact: This study demonstrates the potential to improve poor-quality paced-breathing kidney ASL and suggests broader applicability to free breathing scenarios. Other dynamic body MRI applications may also benefit from this simple motion correction approach.
Wang et al. (Tue,) studied this question.