轻度认知功能障碍患者后扣带回的磁共振扩散张量成像研究

目的 应用磁共振DTI分析轻度认知功能障碍（MCI）患者后扣带回脑白质各向异性分数（FA）值的变化,探讨DTI对轻度认知障碍的诊断价值.方法 选择观察组MCI患者与对照组健康志愿者各18例,应用GE Signa Excite 1.5 T 核磁共振系统进行头颅DTI检查,分别测量2组后扣带回、海马旁回及内囊后肢脑白质的FA值,比较2组测量结果.结果 观察组双侧后扣带回脑白质FA值显著低于对照组,差异有统计学意义（P〈0.05）;2组海马旁回、内囊后肢及胼胝体膝部FA值比较差异无统计学意义（P〉0.05）.结论 DTI作为早期诊断MCI的无创性检查手段,对早期干预及提高患者生存质量具有重要意义.

Diffusion tensor imaging study of cingulum fibers in mild cognitive impairment

Objective To analyze the fractional anisotropy（FA） values of several white matter tracts of patients with mild cognitive impairment （MCI） by using magnetic resonance diffusion tensor imaging （ DTI）, in order to evaluate the value of DTI in diagnosis of mild cognitive impairment. Methods 18 cases of patients with MCI （ observation group） and 18 volun- teers （ control group） participated in the study. MRI was performed with a 1.5-T system to examine head DTI. We measured FA values of selected regions included bilateral posterior cingulate regions, bilateral parahippocampal regions, and bilateral re- gions at the posterior limb of internal capsule in 2 groups. We performed pairwise comparisons in each region of interest be- tween 2 groups. Results The FA value in the bilateral posterior cingnlate regions of observation group were significantly lower than that of control groups, and the difference was statistically significant （ P 〈 0.05 ）. However, the bilateral parahippocampal regions and bilateral posterior limb of internal capsule showed no significant FA differences between 2 groups （ P 〉 0.05 ）. Conclusion DTI is a promising noninvasive testing method for the early diagnosis of patients with MCI, which has important significance in early intervention and improving the quality of life of patients.