title: Quantitative, Organ-Specific Interscanner and Intrascanner Variability for 3 T Whole-Body Magnetic Resonance Imaging in a Multicenter, Multivendor Study.
abstract: BACKGROUND
  Whole-body magnetic resonance (MR) imaging is increasingly implemented in population-based cohorts and clinical settings. However, to quantify the variability introduced by the different scanners is essential to make conclusions about clinical and biological data, and relevant for internal/external validity. Thus, we determined the interscanner and intrascanner variability of different 3 T MR scanners for whole-body imaging.
  
  
  METHODS
  Thirty volunteers were enrolled to undergo multicentric, interscanner as well intrascanner imaging as part of the German National Cohort pilot studies. A comprehensive whole-body MR protocol was installed at 9 sites including 7 different MR scanner models by all 4 major vendors. A set of quantitative, organ-specific measures (n = 20; eg, volume of brain's gray/white matter, pulmonary trunk diameter, vertebral body height) were obtained in blinded fashion. Reproducibility was determined using mean weighted relative differences and intraclass correlation coefficients.
  
  
  RESULTS
  All participants (44 ± 14 years, 50% female) successfully completed the imaging protocol except for two because of technical issues. Mean scan time was 2 hours and 32 minutes and differed significantly across scanners (range, 1 hour 59 minutes to 3 hours 12 minutes). A higher reproducibility of obtained measurements was observed for intrascanner than for interscanner comparisons (intraclass correlation coefficients, 0.80 ± 0.17 vs 0.60 ± 0.31, P = 0.005, respectively). In the interscanner comparison, mean relative difference ranged from 1.0% to 53.2%. Conversely, in the intrascanner comparison, mean relative difference ranged from 0.1% to 15.6%. There were no statistical differences for intrascanner and interscanner reproducibility between the different organ foci (all P ≥ 0.24).
  
  
  CONCLUSIONS
  While whole-body MR imaging-derived, organ-specific parameters are generally associated with good to excellent reproducibility, smaller differences are obtained when using identical MR scanner models by a single vendor.
authors.affiliation: From the *Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg; †Department of Clinical Radiology, Campus Grosshadern, Ludwig-Maximilians University, Munich; ‡Fraunhofer Institute for Medical Image Computing MEVIS, Bremen; §Institute of Neuroscience and Medicine, Jülich Research Centre, Jülich; ∥Department of Cardiology and Nephrology, HELIOS Clinic Berlin Buch, Berlin; ¶Institute for Community Medicine, Ernst-Moritz-Arndt University, Greifswald; #Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen; **Institute of Diagnostic Radiology, and ††Department of Epidemiology and Preventive Medicine, University Hospital Regensburg, Regensburg; ‡‡Department of Diagnostic and Interventional Radiology, University Hospital RWTH Aachen, Aachen; §§Department of Epidemiology, Helmholtz Centre for Infection Research, Braunschweig; ∥∥Department of Diagnostic and Interventional Radiology, Hannover Medical School, Hannover; ¶¶O. Vogt Institute for Brain Research, Heinrich-Heine-University Düsseldorf, Düsseldorf; ##Department of Diagnostic and Interventional Radiology, University Hospital Klinikum rechts der Isar, Munich; ***Department of Radiology and Neuroradiology,University Medicine Greifswald, Ernst-Moritz-Arndt University, Greifswald; and †††Department of Diagnostic and Interventional Radiology, University Hospital Tübingen, Tübingen, Germany.
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Schlett
authors.forename: Thomas
authors.initials: T
authors.lastname: Hendel
authors.forename: Jochen
authors.initials: J
authors.lastname: Hirsch
authors.forename: Sabine
authors.initials: S
authors.lastname: Weckbach
authors.forename: Svenja
authors.initials: S
authors.lastname: Caspers
authors.forename: Jeanette
authors.initials: J
authors.lastname: Schulz-Menger
authors.forename: Till
authors.initials: T
authors.lastname: Ittermann
authors.forename: Florian
authors.initials: F
authors.lastname: von Knobelsdorff-Brenkenhoff
authors.forename: Susanne C
authors.initials: SC
authors.lastname: Ladd
authors.forename: Susanne
authors.initials: S
authors.lastname: Moebus
authors.forename: Christian
authors.initials: C
authors.lastname: Stroszczynski
authors.forename: Beate
authors.initials: B
authors.lastname: Fischer
authors.forename: Michael
authors.initials: M
authors.lastname: Leitzmann
authors.forename: Christiane
authors.initials: C
authors.lastname: Kuhl
authors.forename: Frank
authors.initials: F
authors.lastname: Pessler
authors.forename: Dagmar
authors.initials: D
authors.lastname: Hartung
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Kemmling
authors.forename: Holger
authors.initials: H
authors.lastname: Hetterich
authors.forename: Katrin
authors.initials: K
authors.lastname: Amunts
authors.forename: Matthias
authors.initials: M
authors.lastname: Günther
authors.forename: Frank
authors.initials: F
authors.lastname: Wacker
authors.forename: Ernst
authors.initials: E
authors.lastname: Rummeny
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Kauczor
authors.forename: Michael
authors.initials: M
authors.lastname: Forsting
authors.forename: Henry
authors.initials: H
authors.lastname: Völzke
authors.forename: Norbert
authors.initials: N
authors.lastname: Hosten
authors.forename: Maximilian F
authors.initials: MF
authors.lastname: Reiser
authors.forename: Fabian
authors.initials: F
authors.lastname: Bamberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005858:Germany; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D059629:Signal-To-Noise Ratio; D013997:Time Factors; D051598:Whole Body Imaging / Q000295:instrumentation*