重性抑郁症基于低频振幅的静息态功能磁共振成像研究

Study on resting-state fMRI based on amplitude of low-frequency fluctuation in patients with major depression

目的观察重性抑郁症患者静息态fMRI(rs-fMRI)特点,并探讨其可能发病机制。方法采用基于低频振幅(ALFF)的rs-f MRI对24例重性抑郁症患者和性别、年龄、受教育程度匹配的26例正常对照者进行比较,Spearman秩相关分析探讨各脑区mALFF值与汉密尔顿抑郁量表17项(HAMD-17)评分的相关性。结果与正常对照者相比,重性抑郁症患者双侧背外侧前额叶皮质、右侧眶部额上回、右侧颞下回、左侧岛盖部额下回、左侧内侧额上回、左侧直回mALFF值升高(均P<0.05,AlphaSim校正),双侧补充运动区、右侧后扣带回、右侧楔前叶、左侧舌回mALFF值降低(均P<0.05,AlphaSim校正)。Spearman秩相关分析显示,重性抑郁症患者各脑区mALFF值与HAMD-17评分无关联性(均P>0.05)。结论重性抑郁症患者静息态下神经功能损害主要集中于脑默认网络和边缘系统等多个脑区,提示其可能存在特征性神经功能改变基础。

Objective To observe characteristics of resting-state functional magnetic resonance imaging （rs-fMRI） in patients with major depression and explore the possible pathogenesis. Methods A total of 24 major depression patients and 26 sex-, age- and education-matched healthy controls were scanned with rs-fMRI based on amplitude of low-frequency fluctuation （ALFF）. The correlation between mALFF values of brain regions and Hamilton Depression Rating Scale-17 （HAMD-17） score was analyzed by Spearman rank correlation analysis. Results Compared with control group, mALFF values in bilateral dorsolateral prefrontal cortex （DLPFC）, right orbital superior frontal gyrus, right inferior temporal gyrus, left operculum inferior frontal gyrus, left medial superior frontal gyrus and left gyrus rectus in major depression group were significantly increased （P 〈 0.05, for all; AlphaSim correction）, while mALFF values in bilateral supplementary motor area （SMA）, right posterior cingulate gyrus, right precuneus and left lingual gyrus were significantly reduced （P 〈 0.05, for all; AlphaSim correction）. Spearman rank correlation analysis showed mALFF values of brain regions in major depression patients was not significantly correlated with HAMD-17 score （P 〉 0.05, for all）. Conclusions Abnormal brain spontaneous activity within default mode network （DMN） and limbic system could emerge in major depression patients during resting-state, which may be neurobiological substrate of major depression.