title: A multicenter reproducibility study of single-voxel 1H-MRS of the medial temporal lobe.
abstract: Proton magnetic resonance spectroscopy ((1)H-MRS) has provided evidence for a reduction of N-acetyl-aspartate (NAA) in the medial temporal lobe (MTL) in cerebral disorders such as Alzheimer's Disease. Within the (1)H-MRS study of the German Research Network on Dementia, we determined the multicenter reproducibility of single-voxel (1)H-MRS of the MTL. At five sites with 1.5T MR systems, single-voxel (1)H spectra from the MTL of an identical healthy subject were measured. The same subject was also examined at one of the sites five times to assess intracenter stability. The protocol included water-suppressed spectra with TE 272 ms and TE 30 ms and unsuppressed spectra for absolute quantification of metabolite concentrations. The intracenter reproducibility of absolute NAA concentration, expressed as coefficient of variation (CV), was 1.8%. CV for the concentrations of creatine (Cr), choline (Cho), and myoinositol (MI) and for the ratios NAA/Cr, NAA/Cho, and MI/NAA varied by 11-16%. Intercenter CV was 3.9% for NAA and were below 10% for all other metabolites and metabolic ratios. Our study demonstrates that quantitative assessment of NAA with single-voxel MRS can be performed with high intercenter reproducibility. This is the basis for applying (1)H-MRS in large-scale early recognition and treatment studies in MTL affecting disorders.
authors.affiliation: Department of Radiology, University of Bonn, Sigmund-Freud-Str. 25, D-53105 Bonn, Germany. traeber@uni-bonn.de
authors.forename: Frank
authors.initials: F
authors.lastname: Träber
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Block
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Freymann
authors.forename: Okan
authors.initials: O
authors.lastname: Gür
authors.forename: Thomas
authors.initials: T
authors.lastname: Kucinski
authors.forename: Thilo
authors.initials: T
authors.lastname: Hammen
authors.forename: Gabriele
authors.initials: G
authors.lastname: Ende
authors.forename: Ulrich
authors.initials: U
authors.lastname: Pilatus
authors.forename: Harald
authors.initials: H
authors.lastname: Hampel
authors.forename: Hans H
authors.initials: HH
authors.lastname: Schild
authors.forename: Reinhard
authors.initials: R
authors.lastname: Heun
authors.forename: Frank
authors.initials: F
authors.lastname: Jessen
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D006801:Humans; D007294:Inositol / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D011522:Protons; D012016:Reference Values; D015203:Reproducibility of Results; D013702:Temporal Lobe / Q000378:metabolism*
chemical_list: D011522:Protons; D001224:Aspartic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline