title: Does superficial fat affect metabolite concentrations determined by MR spectroscopy with water referencing?
abstract: It has recently been reported in this journal that local fat depots produce a sizable frequency-dependent signal attenuation in magnetic resonance spectroscopy (MRS) of the brain. If of a general nature, this effect would question the use of internal reference signals for quantification of MRS and the quantitative use of MRS as a whole. Here, it was attempted to verify this effect and pinpoint the potential causes by acquiring data with various acquisition settings, including two field strengths, two MR scanners from different vendors, different water suppression sequences, RF coils, localization sequences, echo times, and lipid/metabolite phantoms. With all settings tested, the reported effect could not be reproduced, and it is concluded that water referencing and quantitative MRS per se remain valid tools under common acquisition conditions.
authors.affiliation: Department of Clinical Research and Institute of Diagnostic, Interventional and Pediatric Radiology, University of Bern, Bern, Switzerland.|Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland.
authors.forename: S P
authors.initials: SP
authors.lastname: Kyathanahally
authors.affiliation: Department of Clinical Research and Institute of Diagnostic, Interventional and Pediatric Radiology, University of Bern, Bern, Switzerland.|Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland.|Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland.
authors.forename: N D
authors.initials: ND
authors.lastname: Fichtner
authors.affiliation: Department of Clinical Research and Institute of Diagnostic, Interventional and Pediatric Radiology, University of Bern, Bern, Switzerland.|Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland.
authors.forename: V
authors.initials: V
authors.lastname: Adalid
authors.affiliation: Department of Clinical Research and Institute of Diagnostic, Interventional and Pediatric Radiology, University of Bern, Bern, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Kreis
mesh_terms: D016477:Artifacts; D001834:Body Water / Q000378:metabolism*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008279:Magnetic Resonance Imaging / Q000295:instrumentation* / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation* / Q000379:methods*; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D050151:Subcutaneous Fat / Q000033:anatomy & histology / Q000378:metabolism*
keywords: MRS; brain; fat; quantification