Pilot study on longitudinal change in pancreatic proton density fat fraction during a weight-loss surgery program in adults with obesity

Yesenia Covarrubias; Kathryn J Fowler; Adrija Mamidipalli; Gavin Hamilton; Tanya Wolfson; Olof Dahlqvist Leinhard; Garth Jacobsen; Santiago Horgan; Jeffrey B Schwimmer; Scott B Reeder; Claude B Sirlin

doi:10.1002/jmri.26671

Pilot study on longitudinal change in pancreatic proton density fat fraction during a weight-loss surgery program in adults with obesity

J Magn Reson Imaging. 2019 Oct;50(4):1092-1102. doi: 10.1002/jmri.26671. Epub 2019 Jan 30.

Authors

Yesenia Covarrubias¹, Kathryn J Fowler¹, Adrija Mamidipalli¹, Gavin Hamilton¹, Tanya Wolfson², Olof Dahlqvist Leinhard^{3

4

5}, Garth Jacobsen⁶, Santiago Horgan⁶, Jeffrey B Schwimmer^{7

8}, Scott B Reeder^{9

10

11

12}, Claude B Sirlin¹

Affiliations

¹ Liver Imaging Group, Department of Radiology, University of California, San Diego School of Medicine, La Jolla, California, USA.
² Computational and Applied Statistics Laboratory, San Diego Supercomputer Center, University of California, San Diego, La Jolla, California, USA.
³ AMRA Medical AB, Linköping, Sweden.
⁴ Center for Medical Image Science and Visualization, Linköping, Sweden.
⁵ Department of Medicine and Health, Linköping, University, Linköping, Sweden.
⁶ Department of Surgery, University of California, San Diego, La Jolla, California, USA.
⁷ Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, University of California, San Diego, La Jolla, California, USA.
⁸ Department of Gastroenterology, Rady Children's Hospital San Diego, San Diego, California, USA.
⁹ Department of Radiology, University of Wisconsin - Madison, Madison, Wisconsin, USA.
¹⁰ Department of Medical Physics, University of Wisconsin - Madison, Madison, Wisconsin, USA.
¹¹ Department of Biomedical Engineering, University of Wisconsin - Madison, Madison, Wisconsin, USA.
¹² Department of Medicine, University of Wisconsin - Madison, Madison, Wisconsin, USA.

Abstract

Background: Quantitative-chemical-shift-encoded (CSE)-MRI methods have been applied to the liver. The feasibility and potential utility CSE-MRI in monitoring changes in pancreatic proton density fat fraction (PDFF) have not yet been demonstrated.

Purpose: To use quantitative CSE-MRI to estimate pancreatic fat changes during a weight-loss program in adults with severe obesity and nonalcoholic fatty liver disease (NAFLD). To explore the relationship of reduction in pancreatic PDFF with reductions in anthropometric indices.

Study type: Prospective/longitudinal.

Population: Nine adults with severe obesity and NAFLD enrolled in a weight-loss program.

Field strength/sequence: CSE-MRI fat quantification techniques and multistation-volumetric fat/water separation techniques were performed at 3 T.

Assessment: PDFF values were recorded from parametric maps colocalized across timepoints.

Statistical tests: Rates of change of log-transformed variables across time were determined (linear-regression), and their significance assessed compared with no change (Wilcoxon test). Rates of change were correlated pairwise (Spearman's correlation).

Results: Mean pancreatic PDFF decreased by 5.7% (range 0.7-17.7%) from 14.3 to 8.6%, hepatic PDFF by 11.4% (2.6-22.0%) from 14.8 to 3.4%, weight by 30.9 kg (17.3-64.2 kg) from 119.0 to 88.1 kg, body mass index by 11.0 kg/m² (6.3-19.1 kg/m² ) from 44.1 to 32.9 kg/m² , waist circumference (WC) by 25.2 cm (4.0-41.0 cm) from 133.1 to 107.9 cm, HC by 23.5 cm (4.5-47.0 cm) from 135.8 to 112.3 cm, visceral adipose tissue (VAT) by 2.9 L (1.7-5.7 L) from 7.1 to 4.2 L, subcutaneous adipose tissue (SCAT) by 4.0 L (2.9-7.4 L) from 15.0 to 11.0 L. Log-transformed rate of change for pancreatic PDFF was moderately correlated with log-transformed rates for hepatic PDFF, VAT, SCAT, and WC (ρ = 0.5, 0.47, 0.45, and 0.48, respectively), although not statistically significant.

Data conclusion: Changes in pancreatic PDFF can be estimated by quantitative CSE-MRI in adults undergoing a weight-loss surgery program. Pancreatic and hepatic PDFF and anthropometric indices decreased significantly.

Level of evidence: 2 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019;50:1092-1102.

Keywords: longitudinal change; pancreatic PDFF; proton density fat fraction; quantitative CSE-MRI; weight-loss surgery (WLS) program.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Adipose Tissue / diagnostic imaging*
Adult
Aged
Bariatric Surgery*
Female
Humans
Image Interpretation, Computer-Assisted / methods*
Longitudinal Studies
Magnetic Resonance Imaging / methods*
Male
Middle Aged
Obesity, Morbid / diagnostic imaging
Obesity, Morbid / surgery*
Pancreas / diagnostic imaging*
Pilot Projects
Prospective Studies
Weight Reduction Programs

Abstract

Publication types

MeSH terms

Grants and funding