High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria.
High Field MR Center, Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria; Department of Psyschiatry & Behavioral Sciences, Stanford University, Palo Alto, CA, USA.
Neuroimage. 2023 Aug 1;276:120175. doi: 10.1016/j.neuroimage.2023.120175. Epub 2023 May 17.
Functional connectivity analysis from rs-fMRI data has been used for determining cortical targets in therapeutic applications of non-invasive brain stimulation using transcranial magnetic stimulation (TMS). Reliable connectivity measures are therefore essential for every rs-fMRI-based TMS targeting approach. Here, we examine the effect of echo time (TE) on the reproducibility and spatial variability of resting-state connectivity measures. We acquired multiple runs of single-echo fMRI data with either short (TE = 30 ms) or long (TE = 38 ms) echo time to investigate inter-run spatial reproducibility of a clinically relevant functional connectivity map, i.e., originating from the sgACC. We find that connectivity maps obtained from TE = 38 ms rs-fMRI data are significantly more reliable than those obtained from TE = 30 ms data sets. Our results clearly show that optimizing sequence parameters can be beneficial for ensuring high-reliability resting-state acquisition protocols to be used for TMS targeting. The differences between reliability in connectivity measures for different TEs could inform future clinical research in optimising MR sequences.
基于 rs-fMRI 的功能连接分析已被用于确定经颅磁刺激（TMS）无创脑刺激治疗应用中的皮质靶区。因此，可靠的连接测量对于每一种基于 rs-fMRI 的 TMS 靶向方法都是至关重要的。在这里，我们研究了回波时间（TE）对静息态连接测量的可重复性和空间可变性的影响。我们采集了具有短（TE=30ms）或长（TE=38ms）回波时间的单回波 fMRI 数据的多个运行，以研究源自 sgACC 的临床相关功能连接图的运行间空间可重复性。我们发现，从 TE=38ms rs-fMRI 数据获得的连接图比从 TE=30ms 数据集获得的连接图更可靠。我们的结果清楚地表明，优化序列参数可以有助于确保高可靠性的静息状态采集协议用于 TMS 靶向。不同 TEs 下连接测量的可靠性差异可以为未来的优化磁共振序列的临床研究提供信息。
