Progressive familial myoclonus epilepsy.

Seven cases of progressive familial myoclonus epilepsy occurring in three families are presented. The patients were in different stages of the illness. The EEG was abnormal in all. It is suggested that these cases belong clinically to the Lafora bodies group. Nystagmus and optic atrophy, seen in one patient, have not been described previously. Myoclonic jerks did not respond to treatment with diazepam and ethosuximide.