title: Seizure outcomes of temporal lobe epilepsy surgery in patients with normal MRI and without specific histopathology.
abstract: Seizure outcome following surgery in pharmacoresistant temporal lobe epilepsy patients with normal magnetic resonance imaging and normal or non-specific histopathology is not sufficiently presented in the literature.
  
  
  
  In a retrospective design, we reviewed data of 263 patients who had undergone temporal lobe epilepsy surgery and identified 26 (9.9%) who met the inclusion criteria. Seizure outcomes were determined at 2-year follow-up. Potential predictors of Engel class I (satisfactory outcome) were identified by logistic regression analyses.
  
  
  
  Engel class I outcome was achieved in 61.5% of patients, 50% being completely seizure free (Engel class IA outcome). The strongest predictors of satisfactory outcome were typical ictal seizure semiology (p = 0.048) and localised ictal discharges on scalp EEG (p = 0.036).
  
  
  
  Surgery might be an effective treatment choice for the majority of these patients, although outcomes are less favourable than in patients with magnetic resonance imaging-defined lesional temporal lobe epilepsy. Typical ictal seizure semiology and localised ictal discharges on scalp EEG were predictors of Engel class I outcome.
authors.affiliation: Department of Neurosurgery, Oslo University Hospital, Sognsvannsveien 20, N-0027, Oslo, Norway. jugiva@ous-hf.no.
authors.forename: Jugoslav
authors.identifier: 0000-0002-0920-2341
authors.initials: J
authors.lastname: Ivanovic
authors.affiliation: Clinical Neurophysiologic Laboratory, Department of Neurosurgery, Oslo University Hospital, Oslo, Norway.
authors.forename: Pål G
authors.initials: PG
authors.lastname: Larsson
authors.affiliation: Department of Clinical Psychology and Neuropsychology, National Centre for Epilepsy, Oslo University Hospital, Oslo, Norway.
authors.forename: Ylva
authors.initials: Y
authors.lastname: Østby
authors.affiliation: Department of Radiology, Oslo University Hospital, Oslo, Norway.
authors.forename: John
authors.initials: J
authors.lastname: Hald
authors.affiliation: Department of Pathology, Oslo University Hospital, Oslo, Norway.
authors.forename: Bård K
authors.initials: BK
authors.lastname: Krossnes
authors.affiliation: Department of Nuclear Medicine, Oslo University Hospital, Oslo, Norway.|Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
authors.forename: Jan G
authors.initials: JG
authors.lastname: Fjeld
authors.affiliation: Oslo Centre for Biostatistics and Epidemiology, Research Support Service, Oslo University Hospital, Oslo, Norway.
authors.forename: Are H
authors.initials: AH
authors.lastname: Pripp
authors.affiliation: Department of Adult Epilepsy, National Centre for Epilepsy, Oslo University Hospital, Oslo, Norway.
authors.forename: Kristin Å
authors.initials: KÅ
authors.lastname: Alfstad
authors.affiliation: Department of Neurosurgery, Oslo University Hospital, Sognsvannsveien 20, N-0027, Oslo, Norway.
authors.forename: Arild
authors.initials: A
authors.lastname: Egge
authors.affiliation: Department of Neurosurgery, Oslo University Hospital, Sognsvannsveien 20, N-0027, Oslo, Norway.
authors.forename: Milo
authors.initials: M
authors.lastname: Stanisic
mesh_terms: D000293:Adolescent; D000328:Adult; D000069279:Drug Resistant Epilepsy / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods*; D055815:Young Adult
keywords: Epilepsy surgery; Normal MRI; Normal or non-specific histopathology; Postsurgical seizure outcomes; Prognostic factors; Temporal lobe epilepsy