title: Proton MR Spectroscopy for Diagnosis and Evaluation of Treatment Efficacy in Parkinson Disease.
abstract: OBJECTIVE
  To assess the neurochemical profile in the putamen of patients with parkinsonian syndromes undergoing L-3,4-dihydroxyphenylalanine (L-DOPA) treatment (drug-on) or after withdrawal of L-DOPA medication (drug-off) compared with healthy volunteers to identify dopaminergic therapy-sensitive biomarkers of Parkinson disease.
  
  
  METHODS
  The local institutional review board approved the study, and all participants gave informed consent. A short echo-time (29 msec) single-voxel (1-cm(3)) proton (hydrogen 1 [(1)H]) magnetic resonance (MR) spectroscopic approach was used at 3 T to explore the metabolic profile in the putamen of patients with Parkinson disease. Spectra obtained from 20 healthy volunteers were blindly compared with spectra obtained from 20 patients with parkinsonian syndromes in drug-on and drug-off conditions in a randomized permuted block study to assess the accuracy of diagnostic biomarkers for Parkinson disease and efficacy of L-DOPA therapy. The statistical tests were two sided, with a type-I error set at α of .05. Random-effects models were used to compare healthy subjects and patients with parkinsonian syndromes in drug-on or drug-off conditions.
  
  
  RESULTS
  Measured concentrations of putaminal total N-acetylaspartate (tNAA) (8.1 ± 0.2 vs 9.4 ± 0.4; P < .01), total creatine (tCr) (7.5 ± 0.2 vs 8.3 ± 0.3; P < .01), and myo-inositol (m-Ins) (3.8 ± 0.3 vs 5.6 ± 0.4; P < .001) were significantly lower in patients with parkinsonian syndromes in drug-off condition than in healthy volunteers. Moreover, L-DOPA therapy restored tNAA (9.1 ± 0.4 vs 8.1 ± 0.2; P < .01) and tCr (8.1 ± 0.3 vs 7.5 ± 0.2; P < .01) levels, whereas m-Ins levels remained unchanged. The combined glutamate and glutamine and choline showed no changes in drug-off or drug-on condition compared with those in control subjects.
  
  
  CONCLUSIONS
  tNAA, tCr, and m-Ins were identified as putative biomarkers of Parkinson disease in the putamen of patients. tNAA and tCr levels are responsive to L-DOPA therapy.
authors.affiliation: From the Department of UFR Medicine, Auvergne University, EA7280, Clermont-Ferrand, France (L.M., F.D.); Center for Magnetic Resonance Imaging (C.C., B.J., A.C., C.S.) and Department of Neurology (B.P., F.D.), CHU Gabriel Montpied, 58 rue Montalembert, 63000 Clermont-Ferrand, France.
authors.forename: Leslie
authors.initials: L
authors.lastname: Mazuel
authors.affiliation: From the Department of UFR Medicine, Auvergne University, EA7280, Clermont-Ferrand, France (L.M., F.D.); Center for Magnetic Resonance Imaging (C.C., B.J., A.C., C.S.) and Department of Neurology (B.P., F.D.), CHU Gabriel Montpied, 58 rue Montalembert, 63000 Clermont-Ferrand, France.
authors.forename: Carine
authors.initials: C
authors.lastname: Chassain
authors.affiliation: From the Department of UFR Medicine, Auvergne University, EA7280, Clermont-Ferrand, France (L.M., F.D.); Center for Magnetic Resonance Imaging (C.C., B.J., A.C., C.S.) and Department of Neurology (B.P., F.D.), CHU Gabriel Montpied, 58 rue Montalembert, 63000 Clermont-Ferrand, France.
authors.forename: Betty
authors.initials: B
authors.lastname: Jean
authors.affiliation: From the Department of UFR Medicine, Auvergne University, EA7280, Clermont-Ferrand, France (L.M., F.D.); Center for Magnetic Resonance Imaging (C.C., B.J., A.C., C.S.) and Department of Neurology (B.P., F.D.), CHU Gabriel Montpied, 58 rue Montalembert, 63000 Clermont-Ferrand, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Pereira
authors.affiliation: From the Department of UFR Medicine, Auvergne University, EA7280, Clermont-Ferrand, France (L.M., F.D.); Center for Magnetic Resonance Imaging (C.C., B.J., A.C., C.S.) and Department of Neurology (B.P., F.D.), CHU Gabriel Montpied, 58 rue Montalembert, 63000 Clermont-Ferrand, France.
authors.forename: Aurélie
authors.initials: A
authors.lastname: Cladière
authors.affiliation: From the Department of UFR Medicine, Auvergne University, EA7280, Clermont-Ferrand, France (L.M., F.D.); Center for Magnetic Resonance Imaging (C.C., B.J., A.C., C.S.) and Department of Neurology (B.P., F.D.), CHU Gabriel Montpied, 58 rue Montalembert, 63000 Clermont-Ferrand, France.
authors.forename: Claudine
authors.initials: C
authors.lastname: Speziale
authors.affiliation: From the Department of UFR Medicine, Auvergne University, EA7280, Clermont-Ferrand, France (L.M., F.D.); Center for Magnetic Resonance Imaging (C.C., B.J., A.C., C.S.) and Department of Neurology (B.P., F.D.), CHU Gabriel Montpied, 58 rue Montalembert, 63000 Clermont-Ferrand, France.
authors.forename: Franck
authors.initials: F
authors.lastname: Durif
mesh_terms: D000368:Aged; D000978:Antiparkinson Agents / Q000627:therapeutic use*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis* / Q000188:drug therapy*; D011446:Prospective Studies; D011522:Protons; D015203:Reproducibility of Results; D016896:Treatment Outcome
chemical_list: D000978:Antiparkinson Agents; D011522:Protons