Purpose

To explore the effect of vagal nerve stimulation (VNS) on spontaneous brain activity in patients with drug-resistant epilepsy (DRE).

Methods

15 patients and eight healthy controls (HC) were enrolled and scanned by resting-state functional MRI to investigate changes in the fractional amplitude of low-frequency fluctuation (fALFF) and regional homogeneity (ReHo). A two-sample t-test or paired sample t-test was used to compare activity between the HCs, preoperative patients (EP-pre), and postoperative patients (EP-post). We also performed correlation analyses to examine the seizure improvement ratio.

Results

The voxel-level analyses indicated that, compared with the HC, the EP-pre group exhibited decreased or increased fALFF and ReHo in the frontal cortex, temporal cortex, precentral/postcentral gyrus, amygdala, insula, cerebellum, and lingual gyrus. Furthermore, compared with the EP-pre group, the EP-post group exhibited decreased or increased fALFF and ReHo in the frontal cortex, temporal cortex, precentral gyrus, insula, anterior/median cingulate gyri, and cerebellum. The regions of interest-level analyses indicated that, compared with HC, the EP-pre group exhibited decreased fALFF or ReHo in the caudate nucleus, supramarginal gyrus, precuneus and middle temporal gyrus. Furthermore, compared with the EP-pre group, the EP-post group exhibited increased fALFF or ReHo in the olfactory cortex, gyrus rectus, and superior temporal gyrus. Increased ReHo in the right superior or middle temporal gyrus was positively correlated with the improvement ratio.

Conclusions

Altered regional activity in DRE patients was reorganized after 3 months of stimulation. Increased ReHo in the right superior or middle temporal gyrus was implicated in VNS-induced improvement in seizure frequency.

中文翻译：

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迷走神经刺激对耐药性癫痫患者自发区域脑活动影响的静息态功能性 MRI 研究。

目的

探讨迷走神经刺激（VNS）对耐药性癫痫（DRE）患者自发性脑活动的影响。

方法

招募了 15 名患者和 8 名健康对照 (HC)，并通过静息状态功能 MRI 进行扫描，以研究低频波动的分数幅度 (fALFF) 和区域均匀性 (ReHo) 的变化。使用双样本 t 检验或配对样本 t 检验来比较 HC、术前患者 (EP-pre) 和术后患者 (EP-post) 之间的活动。我们还进行了相关分析以检查癫痫发作改善率。

结果

体素水平分析表明，与 HC 相比，EP-pre 组在额叶皮层、颞叶皮层、中央前/中央后回、杏仁核、岛叶、小脑和舌回中的 fALFF 和 ReHo 减少或增加。此外，与 EP-pre 组相比，EP-post 组的额叶皮层、颞叶皮层、中央前回、岛叶、前/中扣带回和小脑的 fALFF 和 ReHo 减少或增加。兴趣水平区域分析表明，与 HC 相比，EP-pre 组在尾状核、缘上回、楔前叶和颞中回中的 fALFF 或 ReHo 减少。此外，与 EP-pre 组相比，EP-post 组的嗅觉皮层、直回和颞上回的 fALFF 或 ReHo 增加。

结论

在刺激 3 个月后，DRE 患者中改变的区域活动被重组。右侧颞上回或中回的 ReHo 增加与 VNS 诱导的癫痫发作频率改善有关。