The influence of cervical spinal cord stimulation on induced epileptic discharges in rats

Abstract

Spinal cord stimulation (SCS), also known as dorsal column stimulation, is a novel technique used widely in pain surgery. However, its effect on other pathologies such as epileptic disorders is unknown. The aim of this study is to evaluate the influence of electrical epidural stimulation of the upper cervical region on epileptic cortical discharges. The long term goal is to elucidate and evaluate a therapeutic central nervous system (CNS) electrical stimulation methodology to treat epilepsy. Twelve Wistar female rats were randomly divided into two groups. In group 1 (six rats under general anesthesia), C2-3 laminectomies were performed and epidural electrodes were placed to perform SCS. To induce epileptic discharges, 1 ml (200 IU) penicillin G was microinjected into the left somatomotor cortex via left stereotactic parietal craniotomies, 0.01 to 0.1 mA at 2 Hz was used to stimulate the spinal cord. In group 2 (the control group, six rats under general anesthesia), C2-3 laminectomies were performed without electrode placement and epileptic discharges were induced with penicillin G microinjections, as described above. Both groups were monitored with digital electroencencephalography (EEG) for 70 min in seven stages and recordings analyzed with power spectral analysis. Spinal cord stimulation decreased penicillin-induced median values of epileptic discharges. Epileptic wave frequencies decreased significantly with increasing intensities of SCS. The results of this study suggest that SCS used for drug resistant epilepsies may be a viable alternative treatment modal. © 2006 Elsevier B.V. All rights reserved.