Experimental therapy of epilepsy with transcranial magnetic stimulation -: Lack of additional benefit with prolonged treatment

Objective: To investigate the effect of three months of low-frequency repetitive transcranial magnetic stimulation (rTMS) treatment in intractable epilepsy. Methods: Five patients (four males, one female; ages 6 to 50 years), were enrolled in the study; their epilepsy could not be controlled by medical treatment and surgery was not indicated. rTMS was performed twice a week for three months; patients kept records of seizure frequency for an equal period of time before, during, and after rTMS sessions. rTMS was delivered to the vertex with a round coil, at an intensity 5% below motor threshold. During rTMS sessions, 100 stimuli (five series of 20 stimuli, with one-minute intervals between series) were delivered at a frequency of 0.3 Hz. Results: Mean daily number of seizures (MDNS) decreased in three patients and increased in two during rTMS- one of these was treated for only one month; the best result was achieved in a patient with focal cortical dysplasia (reduction of 43.09% in MDNS). In the whole patient group, there was a significant (p<0.01) decrease in MDNS of 22.8%. Conclusions: Although prolonged rTMS treatment is safe and moderately decreases MDNS in a group of patients with intractable epilepsy, individual patient responses were mostly subtle and clinical relevance of this method is probably low. Our data suggest, however, that patients with focal cortical lesions may indeed benefit from this novel treatment. Further studies should concentrate on that patient subgroup.