Background and objectives: Vagus nerve stimulation (VNS) is an approved treatment of partial onset seizures and has recently shown antidepressant effects in patients with treatment-resistant depression. This study was conducted to investigate whether acute VNS has an influence on cerebral blood flow (CBF) in humans.
Methods: This investigation was designed as an add-on study. In 10 patients with an implanted stimulator who participated in a multicenter clinical trial to evaluate the efficacy of VNS in depression, CBF was investigated by functional transcranial Doppler at baseline (before the stimulator was turned on for the first time) and during stimulation with three different stimulation intensities in a randomized order.
Results: Immediately after every increase of the current, CBF velocity showed a nonsignificant increase. Otherwise, no change of CBF above standard deviation could be registered.
Conclusion: Acute VNS does not have an influence on CBF velocity in depressive patients.
Copyright (c) 2005 S. Karger AG, Basel.