SEIZURE AND EEG PATTERNS IN ANGELMANS SYNDROME

We studied the seizure and polygraphic patterns of 18 patients with An gelman's syndrome. All patients showed movement problems. Eleven patie nts were also reported to have long-lasting periods of jerky movements . The polygraphic recording showed a myoclonic status epilepticus in n ine of them. Seven patients had partial seizures with eye deviation an d vomiting, similar to those of childhood occipital epilepsies. These seizures and electroencephalographic patterns suggest that Angelman's syndrome occurs in most of the patients as a nonprogressive, age-depen dent myoclonic encephalopathy with a prominent occipital involvement. These findings indicate that, whereas ataxia is a constant symptom in Angelman's syndrome, the occurrence of a transient myoclonic status ep ilepticus may account for the recurrence of different abnormal movemen ts, namely the jerky ones.