Polyspike ictal onset absence seizures.
Polyspike ictal-onset absence seizures may predict an unfavorable response to treatment in patients with epilepsy. The authors assessed absences in adults with idiopathic generalized epilepsy (IGE) associated with polyspike onset before classic 3-Hz generalized spike-and-waves (GSW). Seven adults with absences undergoing video EEG were accompanied by 3-Hz GSW, preceded by polyspike-ictal onset by >1 second in two or more seizures. The clinical profile, interictal, and ictal EEG noted had at least 1-year follow-up. A total of 1,164 patients underwent video EEG, with 58 (5%) receiving a diagnosis of IGE or subsyndrome. All seven patients with absence seizures had an ictal EEG pattern of polyspike onset prior to 3-Hz GSW. Four female and three male adults (mean age, 28.9 years) had absence as their primary seizure type. All but one had seizure onset between 4 and 20 years and failed at least two broad-spectrum antiepileptic drug trials. Typical features of IGE were normal neurologic examination, brain MRI, and 3- to 3.5-Hz GSW and generalized polyspike-and-waves on interictal EEG. Atypical features included learning disability (2 of 7), absence status (1 of 7), and paroxysmal fast activity during nonrapid eye movement sleep (3 of 7).


CONCLUSIONS
Polyspikes are common during video EEG in adults with IGE. Absence seizures with polyspike onset 3-Hz GSW suggest an intermediary form of IGE that may be drug resistant.
Tatum
William O
WO
Tampa General Hospital, University of South Florida, Department of Neurology, Mayo College of Medicine, Mayo Clinic, Jacksonville, FL 32224, USA. wotiv@aol.com
Ho
Son
S
Benbadis
Selim R
SR
D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use; D001921:Brain / Q000473:pathology / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004569:Electroencephalography / Q000379:methods; D004832:Epilepsy, Absence / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D004829:Epilepsy, Generalized / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D013997:Time Factors; D014741:Video Recording / Q000379:methods; D055815:Young Adult
D000927:Anticonvulsants