Simultaneous Liver Water T1 and Fat Fraction Mapping using Chemical-Shift Encoded Modified Look-Locker Inversion Recovery Imaging

Motivation: Liver T1 can vary with inflammation/fibrosis, and with PDFF. Differentiating these may provide additional insight into disease progression. Goal(s): To develop and assess a chemical shift-encoded (CSE) MOLLI technique that enables simultaneous estimation of water-specific T1 and PDFF in a single breath-hold. Approach: This study included asymptomatic individuals and participants with steatotic and non-steatotic liver diseases. Imaging included six-echo CSE MRI (mDIXON Quant®), single-echo MOLLI with fat suppression (FS), and CSE MOLLI. Results: CSE MOLLI-derived T1-W and PDFF correlated very strongly with FS MOLLI (r = 0.93) and mDIXON Quant (r = 0.99) in 20 participants (PDFF median: 4.8%, range: 0.2-44.3%). Impact: This study introduces a single breath-hold CSE MOLLI technique that simultaneously estimates water-specific T1 and fat fraction in the liver, showing strong correlations with established methods. This approach aids in differentiating the impacts of water and fat on liver health.