Point-of-care magnetic resonance technology to measure liver fat: Phantom and first-in-human pilot study

Magn Reson Med. 2022 Oct;88(4):1794-1805. doi: 10.1002/mrm.29304. Epub 2022 May 25.

Abstract

Purpose: To assess feasibility and accuracy of point-of-care (POC) NMR-proton density fat fraction (PDFF) in phantoms and in a human pilot study in a POC setting.

Methods: POC NMR (LiverScope, Livivos, San Diego CA) PDFF measurements were obtained of certified phantoms with known PDFF values (0%-40%). In an institutional review board-approved, Health Insurance Portability and Accountability Act-compliant prospective human study, a convenience sample of participants from an obesity clinic was enrolled (November 2020 to June 2021). The inclusion criteria required body mass index (BMI) = 27-40 kg/m2 and willingness to undergo POC NMR and MRI-PDFF measurements. Liver PDFF was measured by POC NMR and, within 35 days after, by a confounder corrected CSE MRI PDFF acquisition and reconstruction method. The adverse events were documented and linear regression analyses were performed.

Results: POC NMR-PDFF measurements agreed with known phantom PDFF values (R2 = 0.99). Fourteen participants were enrolled in the pilot human study. MRI-PDFF could not be obtained in 4 participants (claustrophobia reaction, n = 3, exceeded size of MR scanner bore, n = 1). POC NMR was unevaluable in 2 participants (insufficient signal penetration depth, n = 1, failure to comply with instructions, n = 1). Technical success was 11 of 13 (85%) for POC NMR PDFF. In 7 participants (4 female; 31-74 years old; median BMI 35 kg/m2 ), MRI-PDFF (range, 2.8%-18.1%), and POC NMR-PDFF (range, 3%-25.2%), agreed with R2 = 0.94. POC NMR had no adverse events.

Conclusion: POC NMR measures PDFF accurately in phantoms and, in a first-in-human pilot study, is feasible and accurate in adults with obesity. Further testing to determine precision and accuracy across larger and more diverse cohorts is needed.

Keywords: diffusion contrast; hepatic steatosis; point of care magnetic resonance; proton density fat fraction.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Aged
  • Female
  • Humans
  • Liver / diagnostic imaging
  • Liver / pathology
  • Magnetic Resonance Imaging / methods
  • Magnetic Resonance Spectroscopy / methods
  • Middle Aged
  • Non-alcoholic Fatty Liver Disease* / diagnostic imaging
  • Non-alcoholic Fatty Liver Disease* / pathology
  • Obesity / diagnostic imaging
  • Obesity / pathology
  • Pilot Projects
  • Point-of-Care Systems*
  • Prospective Studies
  • Protons
  • Reproducibility of Results
  • Technology

Substances

  • Protons