Evaluation of Liver Fat Content with Magnetic Resonance Spectroscopy in Overweight Subjects as an early Detector of Fatty Liver Disease and Correlation with Liver Biopsy

Abstract

Aim: To evaluate magnetic resonance spectroscopy (MRS) imaging in the estimation of liver fat content (LFC) in obese subjects as an early and noninvasive diagnostic tool for the detection of nonalcoholic fatty liver disease (NAFLD) and correlation of its accuracy with liver biopsy. Methods: A total of 45 subjects with a variable body mass index (BMI) included 30 healthy subjects and 15 patients with NAFL underwent MRS of the liver. MRS. Subjects were divided according to the median liver fat content in a normal range (≤5.1%); low (5.2 to ≤6.9); moderate (7 to ≤8.9); and high (> 9). Results: In 45 subjects and patients with BMI ranging from 19.0 to 42.9 kg/m² the mean fat contents of liver by MRS were 4.57, 6.15, and 8.7 in healthy subjects, overweight and obese subjects, and NAFLD patients respectively. There were high significant correlation between the result of MRS score and the results of liver biopsy (P=0.001).An intercept of the regression line with the x-axis was observed at 5.1%, discriminating between normal and elevated LFC with high sensitivity (95%) and specificity (98%). Conclusion: In-phase and out-of-phase imaging can be used to rapidly estimate the LFC in subjects and patients without or with NAFLD. The cutoff value of 5.1% enables objective rapid and reliable discrimination of normal LFC from elevated LFC.