Intracranial Ictal Electroencephalographic Patterns in Parietal Lobe Epileptic Seizures : Correlation with Surgical Outcome

J Korean Neurol Assoc > Volume 19(5); 2001 > Article

Journal of the Korean Neurological Association 2001;19(5): 478-484.

두정엽간질의 두개내 발작 뇌파양상 : 수술 예후와의 연관성

손영민, 한설희*·서대원 ·김한영

성균관대학교 의과대학 삼성서울병원 신경과학교실,충북대학교 의과대학 신경과학교실*

Intracranial Ictal Electroencephalographic Patterns in Parietal Lobe Epileptic Seizures : Correlation with Surgical Outcome

Young-Min Shon, M.D., Seol-Heui Han, M.D., Dae Won Seo, M.D., Hahn Young Kim, M.D.

"Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine Department of Neurology, Chungbuk National University*"

Abstract

"Backgrounds : Parietal lobe epilepsy is uncommon and its intracranial ictal EEG findings have not been well eluci-dated. We investigated the ictal EEG patterns of epilepsy originating from the parietal lobe and its adjacent areas recorded by intracranial subdural electrode arrays. Methods : The following intracranial ictal EEG patterns from twenty patients who underwent epilepsy surgery for medically intractable parietal lobe epilepsy were studied: 1) Anatomical ictal onset area [pure parietal (PP), combined parietal and extraparietal, such as fronto-parietal, temporo-parietal, etc. (EP)], 2) localization within the parietal lobe, 3) extent of the ictal onset zone, 4) the number of ictal onset zones, 5) fre-quency and waveform of ictal onset rhythms, and 6) type of spreading. Results : Twelve patients (60%) were seizure-free (5 from PP, 7 from EP) and 8 were with persistent seizures (3 from PP, 5 from EP). Eight patients (40%) had ictal onset from PP and 12 were from EP. There were! Significant correlations with surgical outcome (p<0.05) in two vari-ables: extent of ictal onset zone and type of spread. Patients with focal onset zones (n=9) showed better outcomes (eight are seizure-free) than those with wide ictal onset zones (4 out of 7 are seizure-free). Patients with slow spreading pat-terns showed better outcomes (12 from 16 are seizure-free) than those with fast spreading outcomes (all of them had persistent seizures). Conclusions : The extent of ictal onset zones correlates with surgical outcomes. The patterns of intracranial ictal EEG are helpful in predicting the surgical outcomes for parietal lobe epilepsy. J Korean Neurol Assoc 19(5):478~484, 2001 Key Words : Parietal lobe epilepsy, Intracranial EEG, Ictal EEG pattern, Ictal onset zone, Surgical outcome"