Ictal Stereo-Electroencephalography Onset Patterns of Mesial Temporal Epilepsy. (16th November 2020)

• Record Type: Journal Article
• Authors: Feng, Rui; Hameed, N.U. Farruk; Hu, Jie; Lang, Liqin; Pan, Li
• Is Part Of: Neurosurgery. Volume 67(2010)Supplement 1
• Publication Date: 2020-11-16
• Subjects: Nervous system -- Surgery -- Periodicals; 617.48005
• DOI: 10.1093/neuros/nyaa447_679
• Languages: English
• ISSNs: 0148-396X

Abstract

Abstract: INTRODUCTION: Identification of epileptogenic characteristics and various epilepsy onset patterns has gained significant researches in recent years. For mesial temporal epilepsy (MTE) however, differences in stereo-electroencephalography (SEEG) onset patterns and their clinical implications remains unclear. METHODS: We analyzed the data of 28 consecutive patients with MTE who underwent non-invasive evaluations, SEEG evaluation and resective surgeries. Cases were classified into either mesial temporal sclerosis (MTS) group or non-MTS group in which mesial temporal structures appeared normal or with subtle abnormality on magnetic resonance imaging (MRI). RESULTS: Engel I outcome was achieved by 20 (71.4%) patients. MTS was observed in 15 (53.6%) patients. Thirteen patients had one ictal onset pattern, 15 had two or more ictal onset patterns. No difference was observed in terms of outcome between patients with single or multiple ictal onset patterns in unilateral mesial temporal structures. Patients with seizure-onsets originating from outside the resected temporal lobe (multiple onsets) had poorer prognosis ( P < .05). We identified five patterns of seizure-onset in MTE and found seizure onset zones (SOZ) differed significantly across the 5 patterns, with low-voltage fast activity (LVFA)-onset pattern having the highest median ratio ( P < .05). The periodic spike-onset type was associated with MTS ( P < .05) and the burst-onset type with non-MTS lesions ( P < .05). CONCLUSION: Distinct ictal SEEG onset patterns of MTE were identified and two of them correlate with MRI findings. In addition, we show multiple seizure-onset patterns in unilateral mesial temporal structures not necessarily mean poor prognosis. However, multiple onsets including ones originating from outside the resected temporal lobe have significantly poorer prognosis.