Resting-state functional connectivity changes with microburst vagus nerve stimulation therapy

Area of Science:

• Neuroscience
• Epilepsy Research
• Medical Technology

Background:

• Drug-resistant epilepsy (DRE) poses significant challenges to patient quality of life.
• Microburst vagus nerve stimulation (μVNS) is an emerging therapy targeting DRE.
• Thalamic plasticity is a proposed mechanism for μVNS efficacy.

Purpose of the Study:

• To investigate the role of thalamic resting-state functional connectivity (rsFC) in the therapeutic effects of μVNS.
• To determine if baseline thalamic rsFC predicts long-term seizure frequency changes in DRE patients undergoing μVNS.
• To compare rsFC patterns between focal and generalized DRE.

Main Methods:

• Prospective study involving 28 DRE patients (18 focal, 10 generalized).
• 3T resting-state fMRI was performed at baseline, 2 weeks, and 6 months post-μVNS implantation.
• rsFC analysis used automated anatomical atlas (AAL) regions; correlations assessed baseline rsFC with 12-month seizure reduction.

Main Results:

• Generalized DRE showed stronger baseline rsFC than focal DRE.
• Significant longitudinal rsFC changes were observed in both groups, with distinct patterns involving the thalamus.
• In focal DRE, baseline rsFC between the thalamus and specific cortical regions negatively correlated with long-term seizure reduction.

Conclusions:

• Baseline thalamic rsFC is a significant predictor of μVNS treatment response in focal DRE.
• rsFC may serve as a potential imaging biomarker to personalize μVNS therapy for focal epilepsy.
• The relationship between thalamic rsFC and μVNS efficacy may differ between focal and generalized DRE subtypes.