Clinical and neuroimaging characteristics in patients with secondary bilateral synchrony (SBS) on EEG

J Korean Neurol Assoc > Volume 15(5); 1997 > Article

Journal of the Korean Neurological Association 1997;15(5): 990-995.

뇌파에서 이차적 양측성 동기화(Secondary Bilateral Synchrony, SBS)를 보이는 환자에서의 임상적, 뇌영상학적 소견

남현우, 박성호, 김종민, 이상건, 노재규

보라매병원 신경과, 서울대학교 의대 신경과

Clinical and neuroimaging characteristics in patients with secondary bilateral synchrony (SBS) on EEG

Hyunwoo Nam, M.D. , Seong-Ho Park, M.D. , Jong-Min Kim, M.D.* , Sang-kun Lee, M.D.*, Jae-Kuy Roh, M.D. *

Dept of Neurology, Boramae City Hospital, Dept of Neurology, College of Medicine, Seoul National University*

Abstract

Rationaele : Secondary bilateral synchrony(SBS) is not an unusual finding to the EEGers, but its Significance is not well-delineated. We reviewed the clinical EEG, and neuroimaging characteristicts in patients with SBS. Method : Patients who were admitted for presurgical evaluation of intractable epilepsy were classified on the basis of video-EEG monitoring, prolonged interictal EEG, MRI, ictal SPECT, PET, and, in a few cases, the surgical results. We analyzed clinical, electrophysiological, and neuroimaging characteristics of patients with SBS by comparing them, with those without SBS. Results : Among 319 patients who were admitted for presurgical epilepsy evaluation, 26 patients had SBS(8.2%). Medial temporal lobe epilepsy was predominant as a whole(140/319, 43.9%), but frontal lobe epilepsy(FLE) was main syndrome in the SBS group(16/26, 61.5%). Multifocal irritative zones were present in 12.5% of FLE with SBS group(2/16) and in 4.8% of FLE without SBS group(2/42). In FLE with SBS group, the location of ictal onset zone was parasaggital in 32%(5/16) and multifocal in 37%(6/16). There was a tendency to develop secondary generalized tonic clonic seizure in FLE with SBS group than in FLE without SBS group. Neuroimaging modalities revealed frontal abnormalities more accurately in FLE with SBS group than in FLE without SBS group. Conclusion : Frontal lobe as an epileptogenic zone is an important factor in generating SBS and SBS seems to facilitate seizure spreading to the contralateral hemisphere.