title: Multivoxel proton magnetic resonance spectroscopy of inflammatory and neoplastic lesions of the canine brain at 3.0 T.
abstract: OBJECTIVE
  To describe findings of 3.0-T multivoxel proton magnetic resonance spectroscopy ((1)H-MRS) in dogs with inflammatory and neoplastic intracranial disease and to determine the applicability of (1)H-MRS for differentiating between inflammatory and neoplastic lesions and between meningiomas and gliomas.
  
  
  METHODS
  33 dogs with intracranial disease (19 neoplastic [10 meningioma, 7 glioma, and 2 other] and 14 inflammatory).
  
  
  METHODS
  3.0-T multivoxel (1)H-MRS was performed on neoplastic or inflammatory intracranial lesions identified with conventional MRI. N-acetylaspartate (NAA), choline, and creatine concentrations were obtained retrospectively, and metabolite ratios were calculated. Values were compared for metabolites separately, between lesion categories (neoplastic or inflammatory), and between neoplastic lesion types (meningioma or glioma) by means of discriminant analysis and 1-way ANOVA.
  
  
  RESULTS
  The NAA-to-choline ratio was 82.7% (62/75) accurate for differentiating neoplastic from inflammatory intracranial lesions. Adding the NAA-to-creatine ratio or choline-to-creatine ratio did not affect the accuracy of differentiation. Neoplastic lesions had lower NAA concentrations and higher choline concentrations than inflammatory lesions, resulting in a lower NAA-to-choline ratio, lower NAA-to-creatine ratio, and higher choline-to-creatine ratio for neoplasia relative to inflammation. No significant metabolite differences between meningiomas and gliomas were detected.
  
  
  CONCLUSIONS
  (1)H-MRS was effective for differentiating inflammatory lesions from neoplastic lesions. Metabolite alterations for (1)H-MRS in neoplasia and inflammation in dogs were similar to changes described for humans. Use of (1)H-MRS provided no additional information for differentiating between meningiomas and gliomas. Proton MRS may be a beneficial adjunct to conventional MRI in patients with high clinical suspicion of inflammatory or neoplastic intracranial lesions.
authors.affiliation: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, Saint Paul, MN 55108.
authors.forename: Krystina L
authors.initials: KL
authors.lastname: Stadler
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Ober
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Feeney
authors.forename: Carl R
authors.initials: CR
authors.lastname: Jessen
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000032:analysis; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000473:pathology / Q000662:veterinary*; D002794:Choline / Q000032:analysis; D003401:Creatine / Q000032:analysis; D003937:Diagnosis, Differential; D016002:Discriminant Analysis; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D004660:Encephalitis / Q000473:pathology / Q000662:veterinary*; D005910:Glioma / Q000473:pathology / Q000662:veterinary*; D006801:Humans; D008577:Meningeal Neoplasms / Q000473:pathology / Q000662:veterinary*; D008579:Meningioma / Q000473:pathology / Q000662:veterinary*; D066244:Proton Magnetic Resonance Spectroscopy / Q000379:methods; D012189:Retrospective Studies
chemical_list: D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline