title: Interictal estimation of intracranial seizure onset in temporal lobe epilepsy.
abstract: OBJECTIVE
  To evaluate the lateralizing and localizing values of interictal focal slow activity (IFSA), single pulse electrical stimulation (SPES) and (18)FDG PET, in order to estimate their potential to complement ictal intracranial recordings and reduce prolonged monitoring in patients with temporal lobe epilepsy.
  
  
  METHODS
  The study includes 30 consecutive patients with bilateral temporal subdural electrodes and focal seizure onset. IFSA, SPES and (18)FDG PET when available, were visually assessed and their combined lateralization was based on the majority of the individual lateralizing tests.
  
  
  RESULTS
  In the 18 patients who had all three tests, lateralization was congruent with seizure onset areas in 15 (83%). When lateralized (15 patients), (18)FDG PET was always congruent with intracranial seizure onset. In all 12 patients without (18)FDG PET, lateralization combining IFSA and SPES was congruent with seizure onset, including two with bilateral independent seizure onset on subdural monitoring. 22 out of the 23 patients who had surgery enjoyed favorable outcome (Engel I or II).
  
  
  CONCLUSIONS
  Intracranial IFSA and SPES can reliably predict the side and site (mesial versus lateral temporal) of seizure onset when they lateralize to the same side.
  
  
  CONCLUSIONS
  (18)FDG PET can be useful in planning electrode implantation. During intracranial recordings, IFSA and SPES have the potential to reduce telemetry time, risks and costs.
authors: Department of Clinical Neuroscience, King's College London, Institute of Psychiatry, UK; Department of Clinical Neurophysiology, King's College Hospital, London, UK. Electronic address: antonio.valentin@kcl.ac.uk.
authors: Antonio
authors: A
authors: Valentín
authors: Department of Clinical Neuroscience, King's College London, Institute of Psychiatry, UK; Department of Clinical Neurophysiology, King's College Hospital, London, UK; Departamento de Fisiología, Facultad de Medicina, Universidad Complutense, Madrid, Spain.
authors: Gonzalo
authors: G
authors: Alarcón
authors: Clinical PET centre, Guy's and St Thomas' NHS Trust, King's College London, London, UK.
authors: Sally F
authors: SF
authors: Barrington
authors: Departamento de Fisiología, Facultad de Medicina, Universidad Complutense, Madrid, Spain.
authors: Jorge J
authors: JJ
authors: García Seoane
authors: Departamento de Neurofisiología, Hospital Gregorio Marañón, Madrid, Spain.
authors: María C
authors: MC
authors: Martín-Miguel
authors: Department of Neurosurgery, King's College Hospital, London, UK.
authors: Richard P
authors: RP
authors: Selway
authors: Department of Clinical Neuroscience, King's College London, Institute of Psychiatry, UK; Department of Clinical Neurophysiology and Epilepsies, Guy's and St Thomas' NHS Trust, London, UK.
authors: Michalis
authors: M
authors: Koutroumanidis
mesh_terms: D000293:Adolescent; D000328:Adult; D004558:Electric Stimulation; D004567:Electrodes, Implanted; D004569:Electroencephalography; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D012640:Seizures / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D013355:Subdural Space / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D016896:Treatment Outcome
keywords: Electrical stimulation; Epilepsy; Interictal slow; Intracranial recordings; PET