title: Clinical value of liver ultrasound for the diagnosis of nonalcoholic fatty liver disease in overweight and obese patients.
abstract: OBJECTIVE
  Liver ultrasound (US) is usually used in the clinical setting for the diagnosis and follow-up of patients with nonalcoholic fatty liver disease (NAFLD). However, no large study has carefully assessed its performance using a semiquantitative ultrasonographic scoring system in overweight/obese patients, in comparison to magnetic resonance spectroscopy ((1) H-MRS) and histology.
  
  
  METHODS
  We recruited 146 patients and performed: a liver US using a 5-parameter scoring system, a liver (1) H-MRS to quantify liver fat content, and a liver biopsy to assess histology. All measurements were repeated in a subgroup of patients (n = 62) after 18 months of follow-up.
  
  
  RESULTS
  The performance of liver US (parenchymal echo alone) was rather modest, and significantly worse than (1) H-MRS (AUROC: 0.82 [0.69-0.94] vs. 0.96 [0.90-1.00]; P = 0.04). However, the AUROC improved when different echographic parameters were taken into account (AUROC: 0.89 [0.83-0.96], P = 0.15 against (1) H-MRS). Optimum sensitivity for liver US was achieved at a liver fat content ≥12.5%, suggesting that below this threshold, liver US is less sensitive. Liver (1) H-MRS showed a high accuracy for the diagnosis of NAFLD, and correlated strongly with histological steatosis (r = 0.73, P < 0.0001). None of the imaging tests was adequate enough to predict changes over time in histology.
  
  
  CONCLUSIONS
  Despite its widespread use, liver US has several important limitations that healthcare providers should recognize, particularly because of its low sensitivity. Using a combination of echographic parameters, liver US showed a significant improvement in its diagnostic performance, but still was of limited value for monitoring treatment over time.
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA.|Malcom Randall Veterans Administration Medical Center, Gainesville, FL, USA.
authors.forename: Fernando
authors.initials: F
authors.lastname: Bril
authors.affiliation: Division of Diabetes, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
authors.forename: Carolina
authors.initials: C
authors.lastname: Ortiz-Lopez
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA.|Malcom Randall Veterans Administration Medical Center, Gainesville, FL, USA.
authors.forename: Romina
authors.initials: R
authors.lastname: Lomonaco
authors.affiliation: Division of Diabetes, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
authors.forename: Beverly
authors.initials: B
authors.lastname: Orsak
authors.affiliation: Radiology Department, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Freckleton
authors.affiliation: Radiology Department, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
authors.forename: Kedar
authors.initials: K
authors.lastname: Chintapalli
authors.affiliation: Radiology Department, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
authors.forename: Jean
authors.initials: J
authors.lastname: Hardies
authors.affiliation: Clinical Translational Science Institute Human Imaging Core, McKnight Brain Institute, University of Florida, Gainesville, FL, USA.
authors.forename: Song
authors.initials: S
authors.lastname: Lai
authors.affiliation: Pathology Department, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
authors.forename: Felipe
authors.initials: F
authors.lastname: Solano
authors.affiliation: Pathology Department, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.
authors.forename: Fermin
authors.initials: F
authors.lastname: Tio
authors.affiliation: Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA.|Malcom Randall Veterans Administration Medical Center, Gainesville, FL, USA.|Division of Diabetes, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX, USA.|Audie L. Murphy Veterans Administration Medical Center, San Antonio, TX, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Cusi
mesh_terms: D001706:Biopsy; D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D005260:Female; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging* / Q000473:pathology; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000175:diagnosis*; D009765:Obesity / Q000150:complications*; D050177:Overweight / Q000150:complications*; D012372:ROC Curve; D012720:Severity of Illness Index; D014463:Ultrasonography
keywords: NAFLD; NASH; Obesity; hepatic steatosis; steatohepatitis