Natural history of drug resistant seizures: clinical aspects

In an effort to determine the long-term efficacy of surgical therapy for epilepsy, a control group of patients was identified. Both the surgically treated and non-surgical groups were evaluated before and after 5- or 10-year follow-ups for seizure frequency in the preceding 2 years. To date 39 patients have had bona fide partial seizures, with or without secondary generalization, and EEGs with focal epileptiform patterns. Prior to first evaluation, these patients had had seizures for an average of 10 years and were treated with an average of 54 AEDs with documented therapeutic serum levels in most; one-third of the patients participated in experimental studies. After treatment for another 5 years with an average of 2.5 AEDs or 10 years with an average of 4.0 AEDs, no one was seizure free. Fifteen percent had a 75% decrease in seizure frequency and 85% continued to have no significant improvement in seizure control. Thus despite vigorous treatment, these patients who might have been considered surgical candidates continued to have uncontrolled seizures.