A study on posterior cingulate gyrus glutamate levels in mild cognitive impairment patients using proton magnetic resonance spectroscopy with multi-voxel
Chen Shuangqing, Cai Qing,Shen Yuying, Zhao Zhong, Zhou Hua
Department of Radiology, Suzhou Hospital, Nanjing Medical University, Suzhou 215001, China
Abstract:Objective To explore the diagnosis value of quantitative analysis of glutamate(Glu) with mild cognitive impairment (MCI) by proton magnetic resonance spectroscopy (1H-MRS).Methods According to the clinical diagnosis standard for cognitive function, the study group included 20 patients with mild cognitive impairment (MCI group, 9 males and 11 females) and 20 patients with Alzheimer′s disease (AD group,10 males and 10 females), and the control group used 20 healthy volunteers (NC group, 9 males and 11 females). All of the patients and volunteers were scanned by multi voxel 1H-MRS using rapid acquisition with relaxation enhancement (RARE) and point-resolved spectroscopy (PRESS) pulse sequence. The levels of the Glu and Cr were measured in the posterior cingulate gyrus, hippocampus and the frontal gyms cortex automatically by the NUTS-NMR Utility Transform Software. The ratios of Glu/Cr were calculated and compared among the groups. Comparisons of the cognitive function and the 1H-MRS indexes among MCI, AD and NC group were conducted by single factor analysis of variance (one-way ANOVA), between two groups significantly compared with minimal difference method (LSD).Results Gender,age,and the fixed number of year of the education comparison between each group had no statistical difference(P>0.05). MMSE detection showed that cognitive function in the MCI group was lower than that in the NC group, and difference was statistically significant (t=0.427,P<0.05).However,there was significant difference in cognitive function between AD and MCI groups (t=0.366,P<0.05). According to 1H-MRS, Glu/Cr ratios of the posterior cingulate gyri region in AD (0.37±0.03) and MCI (0.30±0.03) groups were significantly decline compared with NC group(0.42±0.03), and different had statistical difference (t=0.271 and 0.652,P<0.05). However, there were no significant difference for Glu/Cr ratios of the hippocampus between MCI (0.40±0.03) and NC (0.41±0.03) groups (t=0.054,P>0.05), but the Glu/Cr ratios of the hippocampus region in AD (0.32±0.03) and NC groups were significantly different 公式,P<0.05). There were no significant changes in Glu/Cr ratios among AD, MCI and NC groups (0.41±0.03, 0.43±0.03 and 0.43±0.03).Conclusion In 1H-MRS test, Glu may be an effective biochemical index of the diagnosis of MCI. 1H-MRS quantitative analysis provides the important basis for the early diagnosis of MCI.
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