Harmonized Multisite MRI-Based Quantification of Human Liver Fat and Stiffness: A Pilot Study

Area of Science:

• Medical Imaging
• Hepatology
• Biomedical Engineering

Background:

• Nonalcoholic fatty liver disease (NAFLD) is a primary driver of end-stage liver disease.
• Current NAFLD diagnosis and monitoring rely on varied clinical data, imaging, and biopsies, hindering multisite trial consistency.
• Intersite imaging differences compromise diagnostic accuracy and repeatability for developing NAFLD treatments.

Purpose of the Study:

• To harmonize 3 Tesla (3T) magnetic resonance imaging (MRI) measurements of liver fat and stiffness across academic sites and vendors.
• To establish consistent quantification of liver fat fraction (FF) and stiffness for NAFLD research.
• To enable reliable multisite clinical trials for NAFLD interventions.

Main Methods:

• Harmonized proton density fat fraction (PDFF) and magnetic resonance spectroscopy (MRS) protocols quantified liver fat in phantoms and participants with obesity.
• Standardized acquisition parameters were used across four different 3T MRI instruments at multiple sites.
• Harmonized magnetic resonance elastography (MRE) quantified liver stiffness at 1.5T and 3T across two sites.

Main Results:

• Proton density fat fraction (PDFF) and MRS measurements showed high repeatability across sites for both phantoms and human participants.
• Magnetic resonance elastography (MRE) measurements of liver stiffness demonstrated high repeatability, though slightly lower than PDFF and MRS.
• Standardized postprocessing at a central data site ensured consistent data analysis.

Conclusions:

• Multisite MRI harmonization for liver fat (PDFF, MRS) and stiffness (MRE) was successfully demonstrated using phantoms and human participants.
• Standardized protocols and postprocessing enhance diagnostic consistency for NAFLD.
• Harmonized MRI techniques are crucial for advancing multisite clinical trials evaluating NAFLD therapies.