Therapeutic effect of repetitive transcranial magnetic stimulation on non-lesional focal refractory epilepsy

The effects of repetitive transcranial magnetic stimulation (rTMS) on epilepsy remain unclear. This study was performed to investigate the effects of low-frequency rTMS on non-lesional focal epilepsy. This was a prospective open-label longitudinal study with four patients with multi-drug-resistant non-lesional focal epilepsy and no control group. The patients received daily doses of 900 pulses of 0.5-Hz stimulation for 10 days over the epileptic foci in neocortical areas determined by electrical source analysis. The outcomes were measured in terms of seizure reduction. The incidences of seizures were measured at baseline (4 weeks), intervention (2 weeks), and follow up (8 weeks). Seizure reduction was observed in three of four subjects. The effects of rTMS persisted over a follow-up period of 8 weeks. One of the four patients did not respond to rTMS and showed no seizure reduction. The low frequency rTMS would be an effective treatment for non-lesional focal refractory epilepsy, may be an adjunctive treatment with conventional medical treatment for refractory epilepsy. These results are therefore useful for planning treatment strategies for patients with refractory epilepsy, as well as for treatment of epilepsy.