Huaxi MR Research Center, Department of Radiology, West China Hospital of Sichuan University, China.
Am J Psychiatry. 2011 Jun;168(6):642-8. doi: 10.1176/appi.ajp.2010.10101419. Epub 2011 Mar 1.
The authors used resting-state functional connectivity MRI to evaluate brain networks in patients with refractory and nonrefractory major depressive disorder.
In a cross-sectional study, 28 patients with refractory major depression, 32 patients with nonrefractory major depression, and 48 healthy comparison subjects underwent scanning using a gradient-echo echo-planar imaging sequence on a 3-T MR system. Thirteen regions of interest that have been identified in the literature as relevant to mood regulation were selected as seed areas. A reference time series was extracted for each seed and used for voxel-wise correlation analysis with the rest of the brain. Voxel-based comparisons of z-value maps among the three groups were performed using one-way analysis of variance followed by post hoc t tests with age and duration of illness as covariates of no interest.
Relative to healthy comparison subjects, both patient groups showed significantly reduced connectivity in prefrontal-limbic-thalamic areas bilaterally. However, the nonrefractory group showed a more distributed decrease in connectivity than the refractory group, especially in the anterior cingulate cortex and in the amygdala, hippocampus, and insula bilaterally; in contrast, the refractory group showed disrupted functional connectivity mainly in prefrontal areas and in thalamus areas bilaterally.
Refractory depression is associated with disrupted functional connectivity mainly in thalamo-cortical circuits, while nonrefractory depression is associated with more distributed decreased connectivity in the limbic-striatal-pallidal-thalamic circuit. These results suggest that nonrefractory and refractory depression are characterized by distinct functional deficits in distributed brain networks.
作者使用静息态功能连接磁共振成像来评估难治性和非难治性重度抑郁症患者的脑网络。
在一项横断面研究中，28 例难治性重度抑郁症患者、32 例非难治性重度抑郁症患者和 48 例健康对照者在 3.0T MR 系统上接受梯度回波回波平面成像序列扫描。选择文献中确定与情绪调节相关的 13 个感兴趣区作为种子区域。为每个种子提取参考时间序列，并用于与大脑其余部分的体素-wise 相关分析。使用单因素方差分析对三组间 z 值图进行体素比较，然后进行年龄和病程作为无兴趣协变量的事后 t 检验。
与健康对照组相比，两组患者双侧额皮质-边缘-丘脑区的连接均明显减少。然而，非难治性组的连接减少更为广泛，特别是在前扣带皮质和双侧杏仁核、海马和岛叶；相比之下，难治性组的功能连接中断主要发生在双侧额皮质和丘脑区域。
难治性抑郁症与丘脑-皮质回路的功能连接中断有关，而非难治性抑郁症与边缘-纹状体-苍白球-丘脑回路中更广泛的连接减少有关。这些结果表明，非难治性和难治性抑郁症的特征是分布式脑网络中存在不同的功能缺陷。
