title: Bone marrow fat quantification in the presence of trabecular bone: initial comparison between water-fat imaging and single-voxel MRS.
abstract: OBJECTIVE
  The purpose of the present study was to test the relative performance of chemical shift-based water-fat imaging in measuring bone marrow fat fraction in the presence of trabecular bone, having as reference standard the single-voxel magnetic resonance spectroscopy (MRS).
  
  
  METHODS
  Six-echo gradient echo imaging and single-voxel MRS measurements were performed on the proximal femur of seven healthy volunteers. The bone marrow fat spectrum was characterized based on the magnitude of measurable fat peaks and an a priori knowledge of the chemical structure of triglycerides, in order to accurately extract the water peak from the overlapping broad fat peaks in MRS. The imaging-based fat fraction results were then compared to the MRS-based results both without and with taking into consideration the presence of short T2* water components in MRS.
  
  
  RESULTS
  There was a significant underestimation of the fat fraction using the MRS model not accounting for short T2* species with respect to the imaging-based fat fraction. A good equivalency was observed between the fat fraction using the MRS model accounting for short T2* species and the imaging-based fat fraction (R(2) = 0.87).
  
  
  CONCLUSIONS
  The consideration of the short T2* water species effect on bone marrow fat quantification is essential when comparing MRS-based and imaging-based fat fraction results.
authors: Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA; Department of Diagnostic and Interventional Radiology, Technische Universität München, Munich, Germany.
authors: Dimitrios C
authors: DC
authors: Karampinos
authors: Gerd
authors: G
authors: Melkus
authors: Thomas
authors: T
authors: Baum
authors: Jan S
authors: JS
authors: Bauer
authors: Ernst J
authors: EJ
authors: Rummeny
authors: Roland
authors: R
authors: Krug
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry*; D050154:Adiposity; D000328:Adult; D000465:Algorithms; D001834:Body Water / Q000737:chemistry*; D001853:Bone Marrow / Q000737:chemistry*; D005260:Female; D005269:Femur / Q000737:chemistry*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D057054:Molecular Imaging / Q000379:methods; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
references: J Magn Reson Imaging. 2011 Apr;33(4):974-9
references: 21448966
references: J Magn Reson Imaging. 2011 Apr;33(4):873-81
references: 21448952
references: Magn Reson Med. 2012 Mar;67(3):638-44
references: 21713978
references: J Magn Reson Imaging. 2012 Nov;36(5):1011-4
references: 22777847
references: Int J Body Compos Res. 2011;9(3):111-122
references: 23204926
references: J Magn Reson Imaging. 2009 Jun;29(6):1332-9
references: 19472390
references: J Magn Reson Imaging. 2005 Aug;22(2):279-85
references: 16028245
references: Obesity (Silver Spring). 2010 Apr;18(4):841-7
references: 19834463
references: Radiology. 2011 Mar;258(3):767-75
references: 21248233
references: Radiology. 2011 Mar;258(3):749-59
references: 21212366
references: J Nucl Med. 2011 Sep;52(9):1482-9
references: 21799087
references: Magn Reson Med. 2004 Jan;51(1):35-45
references: 14705043
references: Magn Reson Med. 2011 Jul;66(1):199-206
references: 21695724
references: J Magn Reson Imaging. 2012 Jan;35(1):117-24
references: 22190287
references: Radiology. 2005 Sep;236(3):945-51
references: 16055699
references: J Magn Reson Imaging. 2013 Feb;37(2):414-22
references: 23165934
references: Magn Reson Med. 2010 Sep;64(3):680-7
references: 20806375
references: Radiology. 2006 Dec;241(3):831-8
references: 17053202
references: Magn Reson Med. 2007 Aug;58(2):354-64
references: 17654578
references: J Magn Reson Imaging. 2007 Oct;26(4):1153-61
references: 17896369
references: J Magn Reson Imaging. 2011 Oct;34(4):729-749
references: 22025886
references: Magn Reson Med. 2012 Feb;67(2):389-404
references: 21661045
references: Magn Reson Med. 2008 Nov;60(5):1122-34
references: 18956464
references: Magn Reson Imaging. 2008 Apr;26(3):347-59
references: 18093781
references: Magn Reson Med. 2011 Nov;66(5):1312-26
references: 21452279
references: Magn Reson Med. 2005 Sep;54(3):636-44
references: 16092103
references: Magn Reson Med. 2008 Mar;59(3):571-80
references: 18306409
references: Magn Reson Med. 2012 Nov;68(5):1495-505
references: 22247024
references: NMR Biomed. 2011 Aug;24(7):784-90
references: 21834002
references: Magn Reson Med. 1992 Aug;26(2):207-17
references: 1513248