基于相干局部一致性方法的抑郁症静息态脑功能研究

A resting-state functional magnetic resonance imaging study of regional brain functioning in patients with major depressive disorder

目的利用静息态fMRI技术，综合脑相干局部一致性（coherence—based regional homogeneity，Cohe—ReHo）的分析方法进一步对抑郁症自发脑活动改变的区域进行定位。方法18例首次发作、既往未服药的抑郁症患者（患者组）以及性别、年龄、受教育年限与患者相匹配的18例健康受试者（对照组）完成了fMRI扫描；将基于Cohe—ReHo的方法应用于数据分析，比较患者组与对照组的ReHo图像；将差异有统计学意义（校正后P〈0．05）区域的局部一致性均值与HDRS总分及其因子分做相关分析以观察其临床相关性。结果患者组右背侧前扣带回（t=-3．498，P〈0．05）、右颞中回（t=-3．454，P〈0．05）及右顶下小叶（t=-4．285，P〈0．05）的Cohe—ReHo减低，左背内侧前额叶（t=3．339，P〈0．05）、左梭状回（t=3．881，P〈0．05）及左小脑（t=3．167，P〈0．05）的Cohe—ReHo增高；左梭状回的ReHo值与焦虑因子存在显著的正相关（r=0．54，P〈0．05）。结论抑郁症患者脑功能改变的区域分布于前额叶、扣带回、颞叶、顶叶及小脑，这些区域局部的异常可能与抑郁症情感与认知相关的功能网络如皮质一边缘、前额叶．小脑等环路的紊乱有关。

Objective Using resting-state functional magnetic resonance imaging （fMRI） and coherence-based regional homogeneity （Cohe-ReHo） to explore regional brain functioning in patients with major depressive disorder （MDD）. Methods A total of 36 subjects, including 18 first-episode, treatmentnaive patients with MDD matched with 18 healthy controls completed the fMRI scans. A recently validated approach Cohe-ReHo was used for the analysis of imaging data. Two-sample t-test was used to compare the ReHo maps between patients and controls. The statistical significance was determined with a corrected P 〈 0. 05. The correlation analyses were performed between the mean ReHo values in regions showing ReHo changes and severity of depressive symptoms assessed by the 17-item Hamilton Depression Rating Scale （HDRS）. Results Compared with controls, MDD patients showed decreased Cohe-ReHo in the right dorsal anterior eingulate gyms （ t = - 3. 498,P 〈 0. 05 ） , right middle temporal gyms （ t = - 3.454,P 〈 0. 05 ） , and right inferior parietal lobule （ t = - 4. 285, P 〈 0. 05 ） but increased Cohe-ReHo in the left dorsal medial prefrontal cortex（ t = 3. 339 ,P 〈 0. 05 ）, left fusiform gyms（ t = 3. 881 ,P 〈 0. 05 ）, and left cerebellum （ t = 3. 167 ,P 〈 0. 05 ）. A significant positive correlation was observed between ReHo value of the left fusiform gyms and anxiety factor of HDRS （ r = 0. 54, P 〈 0. 05 ）. Conclusion Patients with MDD possibly have altered regional brain function in brain areas distributed over the prefrontal lobe, anterior cingulate gyms, temporal lobe, parietal lobe, and cerebellum. Regional functional alteration in these regions may be associated with the disturbance of cognition and emotion related neural networks seen in MDD such as cortical-limbic and prefrontal-cerebellar loops.