Lateralizing value of interictal epileptiform discharge in temporal lobe epilepsy

J Korean Neurol Assoc > Volume 15(1); 1997 > Article

Journal of the Korean Neurological Association 1997;15(1): 67-76.

측두엽간질에서의 interictal epileptiform discharge의 진단적 가치

남현우, 이상건, 박성호, 이상복, 명호진

서울대학교 의대 신경과, 보라매병원 신경과

Lateralizing value of interictal epileptiform discharge in temporal lobe epilepsy

Hyunwoo Nam, M.D., Sang-Kun Lee, M.D., Sung-Ho Park, M.D., Sangbok Lee, M.D., Ho-Jin Myung M.D.

Department of Neurology, College of Medicine, Seoul National University, and Department of Neurology, Boramae Hospital

Abstract

Objective & Background : There have been reports on the lateralizing value of temporal lobe interictal epileptiform discharge(IED), yet it is a matter of debate till now. We studied our patients focusing on the degree of lateralization by which accurate lateralization was possible and also on the significance of bisynchronous IED(BIED) in the lateralization of temporal lobe epilepsy. Method : Fifty two patients were included in the study who were diagnosed as having medial temporal lobe epilepsy through video-EEG monitoring and brain MRI. Twenty four hour sleep-deprived interictal scalp EEG was checked for all of them. After that, we counted the number of independent IED(IIED) and BIED originating from anterior temporal areas. Then we tried to find a reasonable degree of IED above which correct lateralization of epileptogenic area was possible by using brain MRI as a standard. We also tried to find a significance of BIED in the lateralization of temporal lobe epilepsy by comparing the result excluding patients with BIED to that includig patients with BIED. Result : Lateralization of IED was over 80% accurate if the cutoff point was set at 70% and patients with BIED were included, but nearly 100% accurate of the cutoff point was set at 80% and patients with BIED were excluded. Conclusion : Influence of BIED on the accuracy of lateralization by IED is significant, and if the lateralization of IED is over 80% in patients with no BIED, the chance of true lateralization is very high. Key Words : Temporal lobe epilepsy, Lateralization, Interictal epileptiform dis charge(IED), Independent interictal epileptiform discharge(IIED), Bisynchronous interictal epileptiform discharge(BIED).