Reliability of ultrasound hepatorenal index and magnetic resonance imaging proton density fat fraction techniques in the diagnosis of hepatic steatosis, with magnetic resonance spectroscopy as the reference standard.

• Main Authors: Bien Van Tran, Kouichi Ujita, Ayako Taketomi-Takahashi, Hiromi Hirasawa, Takayuki Suto, Yoshito Tsushima
• Format: Article
• Language: English
• Published: Public Library of Science (PLoS) 2021-01-01
• Series: PLoS ONE
• Online Access: https://doi.org/10.1371/journal.pone.0255768

<h4>Purpose</h4>To evaluate the reliability of ultrasound hepatorenal index (US-HRI) and magnetic resonance imaging proton density fat fraction (MRI-PDFF) techniques in the diagnosis of hepatic steatosis, with magnetic resonance spectroscopy proton density fat fraction (MRS-PDFF) as the reference standard.<h4>Materials and methods</h4>Fifty-two adult volunteers (30 men, 22 women; age, 31.5 ± 6.5 years) who had no history of kidney disease or viral/alcoholic hepatitis were recruited to undergo abdominal US, MRI, and MRS examinations. US-HRI was calculated from the average of three pairs of regions of interest (ROIs) measurements placed in the liver parenchyma and right renal cortex. On MRI, the six-point Dixon technique was employed for calculating proton density fat fraction (MRI-PDFF). An MRS sequence with a typical voxel size of 27 ml was chosen to estimate MRS-PDFF as the gold standard. The data were evaluated using Pearson's correlation coefficient and receiver operating characteristic (ROC) curves.<h4>Results</h4>The Pearson correlation coefficients of US-HRI and MRI-PDFF with MRS-PDFF were 0.38 (p = 0.005) and 0.95 (p<0.001), respectively. If MRS-PDFF ≥5.56% was defined as the gold standard of fatty liver disease, the areas under the curve (AUCs), cut-off values, sensitivities and specificities of US-HRI and MRI-PDFF were 0.74, 1.54, 50%, 91.7% and 0.99, 2.75%, 100%, 88.9%, respectively. The intraclass correlation coefficients (ICCs) of US-HRI and MRI-PDFF were 0.70 and 0.85.<h4>Conclusion</h4>MRI-PDFF was more reliable than US-HRI in diagnosing hepatic steatosis.