title: Initial clinical application of modified Dixon with flexible echo times: hepatic and pancreatic fat assessments in comparison with (1)H MRS.
abstract: OBJECTIVE
  Hepatic and pancreatic fat content become increasingly important for phenotyping of individuals with metabolic diseases. This study aimed to (1) evaluate hepatic fat fractions (HFF) and pancreatic fat fractions (PFF) using (1)H magnetic resonance spectroscopy (MRS) and the recently introduced fast mDixon method, and to examine body fat effects on HFF and PFF, (2) investigate regional differences in HFF and PFF by mDixon.
  
  
  METHODS
  HFF and PFF were quantified by mDixon with two flexible echo times and by single voxel (1)H MRS in 24 healthy subjects. The regional differences of PFF within the pancreas were assessed with mDixon. Abdominal visceral and subcutaneous fat was assessed by T1-weighted MRI at 3T.
  
  
  RESULTS
  Both methods correlated well for quantification of HFF (r = 0.98, p < 0.0001) and PFF (r = 0.80, p < 0.0001). However, mDixon showed a higher low limit in HFF and PFF. PFF showed no regional differences using mDixon. In addition, both visceral and subcutaneous fat correlated with pancreatic fat, while only visceral fat correlated with liver fat, employing both (1)H MRS and mDixon.
  
  
  CONCLUSIONS
  The novel and fast two-point mDixon exhibits a good correlation with the gold-standard (1)H MRS for assessment of HFF and PFF, with limited sensitivity for assessing lower fat content.
authors.affiliation: Metabolic Imaging Group, Institute of Clinical Diabetology, German Diabetes Center at Heinrich-Heine University, Auf dem Hennekamp 65, 40225, Düsseldorf, Germany.
authors.forename: Roshan S
authors.initials: RS
authors.lastname: Livingstone
authors.forename: Paul
authors.initials: P
authors.lastname: Begovatz
authors.forename: Sabine
authors.initials: S
authors.lastname: Kahl
authors.forename: Bettina
authors.initials: B
authors.lastname: Nowotny
authors.forename: Klaus
authors.initials: K
authors.lastname: Strassburger
authors.forename: Guido
authors.initials: G
authors.lastname: Giani
authors.forename: Jürgen
authors.initials: J
authors.lastname: Bunke
authors.forename: Michael
authors.initials: M
authors.lastname: Roden
authors.forename: Jong-Hee
authors.initials: JH
authors.lastname: Hwang
mesh_terms: D050153:Abdominal Fat / Q000033:anatomy & histology; D000273:Adipose Tissue / Q000033:anatomy & histology*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008099:Liver / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010179:Pancreas / Q000033:anatomy & histology*; D050151:Subcutaneous Fat / Q000033:anatomy & histology; D051598:Whole Body Imaging