Scott Brian Reeder1, Catherine D. Hines1,
Huanzhou Yu2, Charles A. McKenzie3, Jean H. Brittain4
1Radiology, University of
Wisconsin, Madison, WI, United States; 2Global Applied Science
Laboratory, GE Healthcare, Menlo Park, CA, United States; 3Medical
Biophysics, University of Western Ontario, London, Ontario, Canada; 4Global
Applied Science Laboratory, GE Healthcare, Madison, WI, United States
Proton density fat-fraction (PDFF) is a useful metric for fat quantification, providing a platform- and protocol-independent metric of tissue fat concentration. PDFF is the ratio of unconfounded signal from mobile fat protons, normalized by the total unconfounded signal from mobile fat protons and mobile water protons. Unfortunately, reference assays that measure concentrations of triglycerides do not account for NMR invisible species, and therefore will correlate, but may not agree directly with, PDFF measured with MRI. In this work, the relationship between true tissue fat concentration and PDFF is described and validated using a fat-water-deuterium oxide phantom.