title: Evaluation of liver fat in the presence of iron with MRI using T2* correction: a clinical approach.
abstract: OBJECTIVE
  To assess magnetic resonance imaging (MRI) with conventional chemical shift-based sequences with and without T2* correction for the evaluation of steatosis hepatitis (SH) in the presence of iron.
  
  
  METHODS
  Thirty-one patients who underwent MRI and liver biopsy because of clinically suspected diffuse liver disease were retrospectively analysed. The signal intensity (SI) was calculated in co-localised regions of interest (ROIs) using conventional spoiled gradient-echo T1 FLASH in-phase and opposed-phase (IP/OP). T2* relaxation time was recorded in a fat-saturated multi-echo-gradient-echo sequence. The fat fraction (FF) was calculated with non-corrected and T2*-corrected SIs. Results were correlated with liver biopsy.
  
  
  RESULTS
  There was significant difference (P < 0.001) between uncorrected and T2* corrected FF in patients with SH and concomitant hepatic iron overload (HIO). Using 5 % as a threshold resulted in eight false negative results with uncorrected FF whereas T2* corrected FF lead to true positive results in 5/8 patients. ROC analysis calculated three threshold values (8.97 %, 5.3 % and 3.92 %) for T2* corrected FF with accuracy 84 %, sensitivity 83-91 % and specificity 63-88 %.
  
  
  CONCLUSIONS
  FF with T2* correction is accurate for the diagnosis of hepatic fat in the presence of HIO. Findings of our study suggest the use of IP/OP imaging in combination with T2* correction.
  
  
  CONCLUSIONS
  • Magnetic resonance helps quantify both iron and fat content within the liver • T2* correction helps to predict the correct diagnosis of steatosis hepatitis • "Fat fraction" from T2*-corrected chemical shift-based sequences accurately quantifies hepatic fat • "Fat fraction" without T2* correction underestimates hepatic fat with iron overload.
authors: Department of Radiology, Innsbruck Medical University, Anichstraße 35, 6020 Innsbruck, Austria. benjamin.henninger@i-med.ac.at
authors: Benjamin
authors: B
authors: Henninger
authors: Henninger
authors: H
authors: Benjamin
authors: Christian
authors: C
authors: Kremser
authors: Kremser
authors: K
authors: Christian
authors: Stefan
authors: S
authors: Rauch
authors: Rauch
authors: R
authors: Stefan
authors: Robert
authors: R
authors: Eder
authors: Eder
authors: E
authors: Robert
authors: Werner
authors: W
authors: Judmaier
authors: Judmaier
authors: J
authors: Werner
authors: Heinz
authors: H
authors: Zoller
authors: Zoller
authors: Z
authors: Heinz
authors: Henrik
authors: H
authors: Michaely
authors: Michaely
authors: M
authors: Henrik
authors: Michael
authors: M
authors: Schocke
authors: Schocke
authors: S
authors: Michael
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000368:Aged; D001706:Biopsy; D005234:Fatty Liver / Q000175:diagnosis* / Q000473:pathology*; D005260:Female; D005293:Ferritins / Q000097:blood; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007501:Iron / Q000737:chemistry* / Q000378:metabolism; D019190:Iron Overload / Q000378:metabolism; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D014168:Transferrin / Q000096:biosynthesis
chemical_list: D014168:Transferrin; D005293:Ferritins; D007501:Iron