title: EEG-fMRI in the presurgical evaluation of temporal lobe epilepsy.
abstract: Drug-resistant temporal lobe epilepsy (TLE) often requires thorough investigation to define the epileptogenic zone for surgical treatment. We used simultaneous interictal scalp EEG-fMRI to evaluate its value for predicting long-term postsurgical outcome.
  
  
  
  30 patients undergoing presurgical evaluation and proceeding to temporal lobe (TL) resection were studied. Interictal epileptiform discharges (IEDs) were identified on intra-MRI EEG and used to build a model of haemodynamic changes. In addition, topographic electroencephalographic correlation maps were calculated between the average IED during video-EEG and intra-MRI EEG, and used as a condition. This allowed the analysis of all data irrespective of the presence of IED on intra-MRI EEG. Mean follow-up after surgery was 46 months. International League Against Epilepsy (ILAE) outcomes 1 and 2 were considered good, and 3-6 poor, surgical outcome. Haemodynamic maps were classified according to the presence (Concordant) or absence (Discordant) of Blood Oxygen Level-Dependent (BOLD) change in the TL overlapping with the surgical resection.
  
  
  
  The proportion of patients with good surgical outcome was significantly higher (13/16; 81%) in the Concordant than in the Discordant group (3/14; 21%) (χ(2) test, Yates correction, p=0.003) and multivariate analysis showed that Concordant BOLD maps were independently related to good surgical outcome (p=0.007). Sensitivity and specificity of EEG-fMRI results to identify patients with good surgical outcome were 81% and 79%, respectively, and positive and negative predictive values were 81% and 79%, respectively.
  
  
  
  The presence of significant BOLD changes in the area of resection on interictal EEG-fMRI in patients with TLE retrospectively confirmed the epileptogenic zone. Surgical resection including regions of haemodynamic changes in the TL may lead to better postoperative outcome.
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, Brazil.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Coan
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK MRI Unit, Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK.
authors.forename: Umair J
authors.initials: UJ
authors.lastname: Chaudhary
authors.affiliation: Department of Radiology and Medical Informatics, Geneva University Hospitals, Geneva, Switzerland.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Grouiller
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, Brazil.
authors.forename: Brunno M
authors.initials: BM
authors.lastname: Campos
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK MRI Unit, Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK.
authors.forename: Suejen
authors.initials: S
authors.lastname: Perani
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK MRI Unit, Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK.
authors.forename: Alessio
authors.initials: A
authors.lastname: De Ciantis
authors.affiliation: EEG and Epilepsy Unit and Functional Brain Mapping Laboratory, Neurology Department, University Hospitals and Faculty of Medicine of University of Geneva, Geneva, Switzerland.
authors.forename: Serge
authors.initials: S
authors.lastname: Vulliemoz
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK MRI Unit, Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK.
authors.forename: Beate
authors.initials: B
authors.lastname: Diehl
authors.affiliation: Neurophysics Group, Gleb Wataghin Physics Institute, University of Campinas, Campinas, Brazil.
authors.forename: Guilherme C
authors.initials: GC
authors.lastname: Beltramini
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK MRI Unit, Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK.
authors.forename: David W
authors.initials: DW
authors.lastname: Carmichael
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK MRI Unit, Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK.
authors.forename: Rachel C
authors.initials: RC
authors.lastname: Thornton
authors.affiliation: Neurophysics Group, Gleb Wataghin Physics Institute, University of Campinas, Campinas, Brazil.
authors.forename: Roberto J
authors.initials: RJ
authors.lastname: Covolan
authors.affiliation: Neuroimaging Laboratory, Department of Neurology, University of Campinas, Campinas, Brazil.
authors.forename: Fernando
authors.initials: F
authors.lastname: Cendes
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, University College London, London, UK MRI Unit, Epilepsy Society, Chalfont St Peter, Buckinghamshire, UK.
authors.forename: Louis
authors.initials: L
authors.lastname: Lemieux
mesh_terms: D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D002648:Child; D000069279:Drug Resistant Epilepsy / Q000175:diagnosis* / Q000601:surgery*; D004569:Electroencephalography; D004833:Epilepsy, Temporal Lobe / Q000175:diagnosis* / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007089:Image Enhancement; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010100:Oxygen / Q000097:blood*; D011237:Predictive Value of Tests; D011300:Preoperative Care; D012189:Retrospective Studies; D013702:Temporal Lobe / Q000098:blood supply / Q000601:surgery; D014741:Video Recording; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: FUNCTIONAL IMAGING; IMAGE ANALYSIS; SURGERY