Introduction: Electroconvulsive therapy (ECT) is a commonly used brain stimulation treatment for treatment-resistant or severe depression. This study was planned to find the effects of ECT on brain connectivity by conducting a systematic review and coordinate-based meta-analysis of the studies performing resting state fMRI (rsfMRI) in patients with depression receiving ECT. Methods: We systematically searched the databases published up to July 31, 2020, for studies in patients having depression that compared resting-state functional connectivity (rsFC) before and after a course of pulse wave ECT. Meta-analysis was performed using the activation likelihood estimation method after extracting details about coordinates, voxel size, and method for correction of multiple comparisons corresponding to the significant clusters and the respective rsFC analysis measure with its method of extraction. Results: Among 41 articles selected for full-text review, 31 articles were included in the systematic review. Among them, 13 articles were included in the meta-analysis, and a total of 73 foci of 21 experiments were examined using activation likelihood estimation in 10 sets. Using the cluster-level interference method, one voxel-wise analysis with the measure of amplitude of low frequency fluctuations and one seed-voxel analysis with the right hippocampus showed a significant reduction (p < 0.0001) in the left cingulate gyrus (dorsal anterior cingulate cortex) and a significant increase (p < 0.0001) in the right hippocampus with the right parahippocampal gyrus, respectively. Another analysis with the studies implementing network-wise (posterior default mode network: dorsomedial prefrontal cortex) resting state functional connectivity showed a significant increase (p < 0.001) in bilateral posterior cingulate cortex. There was considerable variability as well as a few key deficits in the preprocessing and analysis of the neuroimages and the reporting of results in the included studies. Due to lesser studies, we could not do further analysis to address the neuroimaging variability and subject-related differences. Conclusion: The brain regions noted in this meta-analysis are reasonably specific and distinguished, and they had significant changes in resting state functional connectivity after a course of ECT for depression. More studies with better neuroimaging standards should be conducted in the future to confirm these results in different subgroups of depression and with varied aspects of ECT.

中文翻译：

---

抑郁症电惊厥治疗大脑的静息状态功能连接：Meta分析以了解其机制

简介：电休克疗法（ECT）是一种常用的脑刺激疗法，用于治疗难治性或重度抑郁症。本研究计划通过对接受 ECT 的抑郁症患者进行静息态 fMRI (rsfMRI) 的研究进行系统回顾和基于坐标的荟萃分析，以发现 ECT 对大脑连接的影响。方法：我们系统地搜索了截至 2020 年 7 月 31 日发布的数据库，以研究抑郁症患者在脉搏波 ECT 治疗前后静息状态功能连接 (rsFC) 的比较。在提取坐标、体素大小、和用于校正与重要簇对应的多重比较和各自的 rsFC 分析测量及其提取方法的方法。结果：在入选全文综述的41篇文章中，31篇被纳入系统综述。其中，13篇文章被纳入荟萃分析，并在10组中使用激活似然估计检查了21个实验的73个焦点。使用集群级干扰方法，一项测量低频波动幅度的体素分析和一项右侧海马体素分析显示左侧扣带回（背前扣带回）显着减少（p < 0.0001）皮层）和右侧海马体与右侧海马旁回分别显着增加（p < 0.0001）。另一项实施网络（后默认模式网络：背内侧前额叶皮层）静息状态功能连接研究的分析显示双侧后扣带回皮层显着增加（p < 0.001）。在神经图像的预处理和分析以及纳入研究的结果报告中存在相当大的可变性以及一些关键缺陷。由于研究较少，我们无法进行进一步分析来解决神经影像变异性和与受试者相关的差异。结论：本荟萃分析中指出的大脑区域具有相当的特异性和区别性，在治疗抑郁症 ECT 后，它们的静息状态功能连接性发生了显着变化。