Efficacy of the ketogenic diet in focal versus generalized seizures

Most reports of the ketogenic diet have focused on its efficacy for general ized seizures. Few data are available regarding its effect on focal seizure s. We retrospectively studied patients (mean = 7.5 years of age) with medic ally intractable epilepsy treated by the ketogenic diet. The predominant se izure types in each patient were classified as generalized (100 patients) o r focal (34 patients) based on ictal electroencephalograms (EEGs) or seizur e semiology and interictal EEG. A seizure reduction of more than 50% compar ed with baseline was seen in nine patients (27%) with focal seizures and 46 patients (46%) with generalized seizures at 3 months, in 10 patients (30%) with focal seizures and 46 patients (46%) with generalized seizures at 6 m onths, and in eight patients (24%) with focal seizures and 42 patients (42% ) with generalized seizures at 12 months. Differences were not significant. Outcome tended to be better in patients younger than 12 years of age compa red with the older age group, but the difference was significant at 6 month s only. Our results suggest that some patients with intractable focal epile psy may respond favorably to the ketogenic diet and that this option should be considered if epilepsy surgery is not possible. (C) 2001 by Elsevier Sc ience Inc. All rights reserved.