Lateralization of mesial temporal lobe epilepsy with chronic ambulatory electrocorticography

• Type of Material: Article
• Authors: David King-Stephens, Pacific Medical Center; Emily Mirro, NeuroPace, Inc.; Peter B Weber, Pacific Medical Center; Kenneth D Laxer, Pacific Medical Center; Paul C Van Ness, University of Texas Southwestern Medical Center; Vicenta Salanova, Indiana University; David C Spencer, Oregon Health and Science University; Christianne N Heck, University of Southern California; Alica Goldman, Baylor College of Medicine; Barbara Jobst, Dartmouth-Hitchcock; Donald C Shields, George Washington University; Gregory K Bergey, Johns Hopkins University; Stephan Eisenschenk, University of Florida; Gregory A Worrell, Mayo Clinic; Marvin A Rossi, Rush Epilepsy Center; Robert Gross, Emory University; Andrew J Cole, Massachusetts General Hospital; Michael R Sperling, Thomas Jefferson University; Dileep R Nair, Cleveland Clinic; Ryder P Gwinn, Swedish Neuroscience Institute; Yong D Park, Georgia Regents University; Paul A Rutecki, University of Wisconsin; Nathan B Fountain, University of Virginia; Robert E Wharen, Mayo Clinic Jacksonville; Lawrence J Hirsch, Yale University; Ian O Miller, Miami Children’s Hospital; Gregory L Barkley, Henry Ford Hospital; Jonathan C Edwards, Medical University of South Carolina; Eric B Geller, Saint Barnabas Medical Center; Michel J Berg, University of Rochester; Toni L Sadler, Via Christi Health; Felice T Sun, NeuroPace, Inc.; Martha J Morrell, Stanford University
• Language: English
• Date: 2015-06-01
• Publisher: Wiley
• Publication Version: Final Published Version
• Copyright Statement: © 2015 Neuropace, Inc. Epilepsia published by Wiley Periodicals on behalf of International League Against Epilepsy.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1111/epi.13010
• Title of Journal or Parent Work: Epilepsia
• ISSN: 0013-9580
• Volume: 56
• Issue: 6
• Start Page: 959
• End Page: 967
• Keywords: SURGERY; Science & Technology; TRIAL; Intracranial EEG; STIMULATION; WITHDRAWAL; Clinical Neurology; BRAIN; RECURRENCE; PARTIAL SEIZURES; Neurosciences & Neurology; ADULTS; Electrocorticography; Ambulatory EEG; Life Sciences & Biomedicine; Localization; Responsive stimulation; EEG monitoring; EEG
• Research Categories: Biology, Neuroscience; Health Sciences, Medicine and Surgery

Abstract

Objective: Patients with suspected mesial temporal lobe (MTL) epilepsy typically undergo inpatient video-electroencephalography (EEG) monitoring with scalp and/or intracranial electrodes for 1 to 2 weeks to localize and lateralize the seizure focus or foci. Chronic ambulatory electrocorticography (ECoG) in patients with MTL epilepsy may provide additional information about seizure lateralization. This analysis describes data obtained from chronic ambulatory ECoG in patients with suspected bilateral MTL epilepsy in order to assess the time required to determine the seizure lateralization and whether this information could influence treatment decisions. Methods: Ambulatory ECoG was reviewed in patients with suspected bilateral MTL epilepsy who were among a larger cohort with intractable epilepsy participating in a randomized controlled trial of responsive neurostimulation. Subjects were implanted with bilateral MTL leads and a cranially implanted neurostimulator programmed to detect abnormal interictal and ictal ECoG activity. ECoG data stored by the neurostimulator were reviewed to determine the lateralization of electrographic seizures and the interval of time until independent bilateral MTL electrographic seizures were recorded. Results: Eighty-two subjects were implanted with bilateral MTL leads and followed for 4.7 years on average (median 4.9 years). Independent bilateral MTL electrographic seizures were recorded in 84%. The average time to record bilateral electrographic seizures in the ambulatory setting was 41.6 days (median 13 days, range 0-376 days). Sixteen percent had only unilateral electrographic seizures after an average of 4.6 years of recording. Significance: About one third of the subjects implanted with bilateral MTL electrodes required >1 month of chronic ambulatory ECoG before the first contralateral MTL electrographic seizure was recorded. Some patients with suspected bilateral MTL seizures had only unilateral electrographic seizures. Chronic ambulatory ECoG in patients with suspected bilateral MTL seizures provides data in a naturalistic setting, may complement data from inpatient video-EEG monitoring, and can contribute to treatment decisions.