title: [Correlates of cognitive impairment in patients with leukoaraiosis by magnetic resonance spectroscopy].
abstract: OBJECTIVE
  To explore the pathological changes in patients with leukoaraiosis (LA) by magnetic resonance spectroscopy (MRS) and examine its relationship with cognitive function.
  
  
  METHODS
  Twenty-three LA patients and 23 age and gender-matched healthy subjects were recruited from the Department of Neurology, Beijing Chaoyang Hospital, Capital Medical University between August 2010 and November 2010. All participants underwent the neuropsychological tests. Multi-voxel chemical shift imaging was performed and the regions of interest were positioned in bilateral frontal white matter. The relative metabolite ratios, involving N-acetyl aspartate/choline ratio (NAA/Cho), N-acetyl aspartate/creatine (NAA/Cr) and choline/creatine (Cho/Cr), were estimated. The correlation of the MRS data and the performance of cognitive function was analyzed.
  
  
  RESULTS
  The LA patients were associated with a worse performance of mini mental state examination (MMSE) versus the healthy controls (24 ± 3 vs 28 ± 1, P < 0.05). Univariate analysis of the MRS data revealed the ratios of NAA/Cho and NAA/Cr significantly decreased in bilateral frontal white matter lesions in the LA group versus the control group (1.72 ± 0.20 vs 1.96 ± 0.36, 1.67 ± 0.17 vs 1.85 ± 0.21, P < 0.05). The values of NAA/Cr and NAA/Cho in normal appearing white matter increased versus the LA group (1.83 ± 0.24 vs 1.72 ± 0.20, 1.78 ± 0.28 vs 1.67 ± 0.17) and decreased versus the control group (1.83 ± 0.24 vs 1.96 ± 0.36, 1.78 ± 0.28 vs 1.85 ± 0.21). But no significant differences were found (P > 0.05). The ratio of Cho/Cr did not differ among 3 groups (P > 0.05). The pathological change of NAA/Cr in white matter lesion in LA patients was markedly correlated with the performance of MMSE (r = 0.47, P < 0.05).
  
  
  CONCLUSIONS
  NAA may be a marker of axonal loss/dysfunction in LA patients. And the changes of NAA/Cr have a positive correlation with cognitive impairment.
authors.affiliation: Department of Neurology, Beijing Chaoyang Hospital, Capital Medical University, China.
authors.forename: Jun-liang
authors.initials: JL
authors.lastname: Yuan
authors.forename: Shuang-kun
authors.initials: SK
authors.lastname: Wang
authors.forename: Xiao-juan
authors.initials: XJ
authors.lastname: Guo
authors.forename: Peng
authors.initials: P
authors.lastname: Peng
authors.forename: Hua
authors.initials: H
authors.lastname: Gu
authors.forename: Wen-hui
authors.initials: WH
authors.lastname: Zhao
authors.forename: Shi-qin
authors.initials: SQ
authors.lastname: Niu
authors.forename: Wen-li
authors.initials: WL
authors.lastname: Hu
mesh_terms: D000368:Aged; D001921:Brain / Q000473:pathology; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000209:etiology / Q000473:pathology*; D005260:Female; D006801:Humans; D049292:Leukoaraiosis / Q000473:pathology* / Q000523:psychology; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009483:Neuropsychological Tests