title: Apparent diffusion coefficients of metabolites in patients with MELAS using diffusion-weighted MR spectroscopy.
abstract: OBJECTIVE
  DW-MR spectroscopy can detect the diffusion coefficients of NAA, Cr, PCr, and Cho and can, therefore, provide some useful information. The aims of this study were to probe the mechanisms underlying the pathogenesis of MELAS and to see whether DW-MR spectroscopy is a useful technique for other diseases besides cerebral infarction.
  
  
  METHODS
  Fifteen healthy volunteers and 10 patients with MELAS were enrolled in the study. All were scanned on a 3T whole-body MR imaging scanner. Fifteen ADCs of the singlet metabolites in the gray matter of the healthy subjects, 10 ADCs of the singlet metabolites in the lesions, and 8 ADCs of the singlet metabolites in the nonaffected areas were used in the statistical analysis, respectively.
  
  
  RESULTS
  The metabolite ADCs of the nonaffected areas and the lesions in the patients were higher than those of the frontal gray matter in the healthy controls. There were significant differences between the metabolite ADCs of the nonaffected areas in patients and those in the healthy controls, and it was the same with the metabolite ADCs of the lesions and those of the healthy controls.
  
  
  CONCLUSIONS
  The increased ADC values of the metabolites reveal that MELAS is a mitochondrial neuronopathy and involves the entire brain. DW-MR spectroscopy is a very useful noninvasive technique, which can show some valuable information that conventional MR imaging cannot display. Thus, it can be applied to brain diseases besides cerebral infarction.
authors.affiliation: Department of Radiology, Center for Functional Imaging, Peking University First Hospital, Peking University, Beijing, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Liu
authors.forename: D
authors.initials: D
authors.lastname: Zheng
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Zhang
authors.forename: S
authors.initials: S
authors.lastname: Xie
authors.forename: J
authors.initials: J
authors.lastname: Xiao
authors.forename: X
authors.initials: X
authors.lastname: Jiang
mesh_terms: D000293:Adolescent; D000328:Adult; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D002648:Child; D002794:Choline / Q000378:metabolism*; D003404:Creatinine / Q000378:metabolism*; D004058:Diffusion; D005260:Female; D006801:Humans; D017241:MELAS Syndrome / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D009474:Neurons / Q000378:metabolism*; D055815:Young Adult
chemical_list: D001224:Aspartic Acid; C000179:N-acetylaspartate; D003404:Creatinine; D002794:Choline