Quantifying Pancreatic Fat Using a Free-Breathing Acquisition in Adults With Obesity Undergoing Diet-Induced Weight Loss-Results From the LION Study.

A free-breathing six-echo radial stack-of-stars acquisition is evaluated as an alternative to Cartesian breath-hold scans for pancreatic fat quantification at 3T. Pancreatic fat deposition was assessed in 18 participants with obesity enrolled in a randomized controlled lifestyle intervention study (LION) using both a Cartesian breath-hold scan and a free-breathing high-resolution stack-of-stars sequence (scan times: 16 s vs. 2 min 55 s). Pancreatic segmentations were initially generated using the VibeSegmentator and subsequently refined manually to reduce the amount of included visceral fat. The Intra-observer reproducibility of the manual refinement was assessed after 3 months using Dice similarity score. SNR for both scan methods was quantified using a large water phantom. Mean segmented volume and mean pancreatic proton density fat fraction (PDFF) values between radial and Cartesian scans were compared. PDFF and volume changes between baseline and post-intervention were investigated for both techniques. Segmented pancreatic volumes and PDFF measurements demonstrated excellent agreement between the radial and Cartesian sequences (Volume: R