A study of multi-voxel 1H-magnetic resonance spectroscopy in patients with vascular cognitive impairment no dementia / 中华神经科杂志

ABSTRACT

Objective To evaluate the roles of multi-voxel proton magnetic resonance spectroscopy (1H-MRS) in the early diagnosis of vascular cognitive impairment no dementia (VCIND).Methods Seventy-eight out-patients and inpatients in Department of Neurology, the second Affiliated Hospital of Soochow University from December 2008 to September 2009 were recruited in this case-control study.Their cognitive functions were assessed with a wide range of neuropsychological battery of tests including Montreal cognitive assessment ( MoCA Beijing Version ), auditory verbal learning test ( AVLT), digital span test (DST), Rey-Osterrieth complex figure test (CFT) ,semantic and phonetic fluency tests, digit symbol coding subtest (DSCT), trail making test (TMT), clock drawing test (CDT) and the Stroop color-word test (SCWT).All patients were classified into vascular cognitive impairment no dementia (VCIND) group and cognitive normal control group based on the results of neuropsychological tests.Eighteen patients with VCIND and 18 gender-, age- and education-matched normal control were randomly selected for the following study.With multi-voxel 1H-MRS, the levels of N-acetylaspartartate (NAA), creatine (Cr) and choline (Cho) in gray matters of bilateral frontal lobe, temporal lobe, parietal lobe and thalamus were measured and the ratios of NAA/Cr, Cho/Cr were compared between the two groups.Meanwhile, the correlations between scores of MoCA and its sub-items and the ratios of NAA/Cr, Cho/Cr were analyzed in VCIND group.Informed consent was obtained from all participants and the study was approved by the Ethics Committee of the hospital.Results Compared with control group, the ratios of NAA/Cr were significantly decreased in bilateral gray matters of thalamus ( left, 1.56 ± 0.49 vs 1.89 ± 0.48, F = 11.222, P = 0.002; right,1.63± 0.45 vs 1.86 ± 0.33, F = 5.358, P = 0.027 ).No significant difference were found in NAA/Cr in gray matters of bilateral frontal lobe, temporal lobe, parietal lobe and Cho/Cr in all regions between two groups ( all P ＞ 0.05 ).In VCIND group, the decreased degree of NAA/Cr in bilateral gray matters of thalamus was significantly positively correlated with the MoCA total score ( r = 0.54, 0.44 ) as well as the sub-scores in tested items of memory ( r = 0.61, 0.49 ), attention ( r = 0.43, 0.36 ), language ( r = 0.39,0.31) and visuospatial or executive( r = 0.29 , 0.33, all P＜0.05 orP＜0.01).Conclusions Cognitive impairment in patients with VCIND maybe related to metabolic dysfunction of neurons in bilateral thalamic.Multi-voxel 1H-MRS plays an important role in early diagnosis and monitoring disease progression of VCIND.