Surgical Outcomes and Prognostic Factors after Epilepsy Surgery in Children with Extratemporal Lobe Epilepsy

Abstract

PURPOSE: In this study, we reviewed surgical outcomes in children with extratemporal lobe epilepsy in our institution and suggested prognostic factors from these results. METHODS: We retrospectively analyzed the records of 59 patients(males n=35, females n=24; mean age of 10 years, mean age of seizure onset of 3 years, mean age of epilepsy surgery of 8 years) who received extratemporal lobe surgery between October 2003 to May 2008. Every patients were performed preoperative evaluation to determine the anatomical location of the ictal onset zone employing video electroencephalography(EEG) monitoring, intraoperative electrocorticography, intracranial EEG monitoring and neuroimagings such as Magnetic Resonance Imaging (MRI), positron emission tomography, interictal/ictal single photon emission computed tomography. Developmental test was taken at pre- and post-operation. RESULTS: Postoperative outcome as defined by Engel's classification were as follows; class I in 42(71.2%), II in 6(10.2%), III in 4(6.8%), and IV in 7(11.9%) patients. We considered six favorable prognostic factors from our data; age at operation, matching accuracy of video-EEG monitoring results, presence of a structural lesion on MRI, using specialized neuromodalities, involvement of lobe at surgery, and nature of the epileptogenic lesion. We also focused on unfavorable prognostic factors; no structural lesion on MRI, low grade of surgical pathology, postoperative epileptiform discharges on EEG. CONCLUSION: Early surgical intervention in pediatric patients with medically refractory seizure who possess focal epileptogenic foci of extratemporal lobe origin has been an effective and safe treatment