Feasibility of a three-step magnetic resonance imaging approach for the assessment of hepatic steatosis in an asymptomatic study population.
OBJECTIVE
To determine the feasibility of a multi-step magnetic resonance imaging (MRI) approach for comprehensive assessment of hepatic steatosis defined as liver fat content of ≥5 % in an asymptomatic population.


METHODS
The study was approved by the institutional review board and written informed consent of all participants was obtained. Participants of a population-based study cohort underwent a three-step 3-T MRI-based assessment of liver fat. A dual-echo Dixon sequence was performed to identify subjects with hepatic steatosis, followed by a multi-echo Dixon sequence with proton density fat fraction estimation. Finally, single-voxel T2-corrected multi-echo spectroscopy was performed.


RESULTS
A total of 215 participants completed the MRI protocol (56.3 % male, average age 57.2 ± 9.4 years). The prevalence of hepatic steatosis was 55 %. Mean liver proton density fat fraction was 9.2 ± 8.5 % by multi-echo Dixon and 9.3 ± 8.6 % by multi-echo spectroscopy (p = 0.51). Dual-echo Dixon overestimated liver fat fraction by 1.4 ± 2.0 % (p < 0.0001). All measurements showed excellent correlations (r ≥ 0.9, p < 0.001). Dual-echo Dixon was highly sensitive for the detection of hepatic steatosis (sensitivity 0.97, NPV 0.96) with good specificity and PPV (0.75 and 0.81, respectively).


CONCLUSIONS
A multi-step MRI approach may enable rapid and accurate identification of subjects with hepatic steatosis in an asymptomatic population.


CONCLUSIONS
• Dual-echo Dixon can rapidly and reliably exclude hepatic steatosis without complex post-processing. • Multi-echo Dixon and multi-echo spectroscopy yield similar results regarding hepatic fat quantification. • Each sequence can be performed in one breath-hold. • These sequences can be implemented in routine abdominal MRI protocols. • Thus hepatic fat can be evaluated without relevant increase in scan time.
Institute of Clinical Radiology, Ludwig-Maximilian University Hospital, Marchioninistraße 15, 81377, Munich, Germany. Holger.Hetterich@med.uni-muenchen.de.
Holger
H
Hetterich
Institute of Clinical Radiology, Ludwig-Maximilian University Hospital, Marchioninistraße 15, 81377, Munich, Germany.
Christian
C
Bayerl
Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.
Annette
A
Peters
Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.|KORA Myocardial Infarction Registry, Central Hospital of Augsburg, Augsburg, Germany.
Margit
M
Heier
Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.
Birgit
B
Linkohr
Institute of Epidemiology II, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.|KORA Myocardial Infarction Registry, Central Hospital of Augsburg, Augsburg, Germany.
Christa
C
Meisinger
Institute of Clinical Radiology, Ludwig-Maximilian University Hospital, Marchioninistraße 15, 81377, Munich, Germany.
Sigrid
S
Auweter
Siemens Healthcare, Erlangen, Germany.
Stephan A R
SA
Kannengießer
Institute of Clinical Radiology, Ludwig-Maximilian University Hospital, Marchioninistraße 15, 81377, Munich, Germany.|Department of Radiology, University of Wisconsin - Madison, Madison, WI, USA.
Harald
H
Kramer
Institute of Clinical Radiology, Ludwig-Maximilian University Hospital, Marchioninistraße 15, 81377, Munich, Germany.
Birgit
B
Ertl-Wagner
Institute of Clinical Radiology, Ludwig-Maximilian University Hospital, Marchioninistraße 15, 81377, Munich, Germany.|Department of Radiology, University Hospital Tübingen, Tübingen, Germany.
Fabian
F
Bamberg
D000328:Adult; D000368:Aged; D058070:Asymptomatic Diseases; D005234:Fatty Liver / Q000175:diagnosis*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results
Dual-echo Dixon; Magnetic resonance imaging; Magnetic resonance spectroscopy; Multi-echo Dixon; Non-alcoholic fatty liver disease