HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Data Supplement Correspondence: Submit a response Alert me when this article is cited Alert me when Correspondence are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sutherling, W. W. Articles by Lopez, N. Search for Related Content PubMed PubMed Citation Articles by Sutherling, W. W. Articles by Lopez, N. Related Collections Magnetic Source Imaging (MSI) Intracranial electrodes Epilepsy surgery Partial seizures

Influence of magnetic source imaging for planning intracranial EEG in epilepsy

From Huntington Medical Research Institutes (W.W.S., D.T., N.L.), Epilepsy and Brain Mapping Program (W.W.S., A.N.M., T.M., Y.M., L.P., N.L.), and Huntington Hospital (W.W.S., A.N.M., T.M., Y.M., L.P., N.L.), Pasadena, CA; and Maxine Dunitz Neurosurgical Institute (A.N.M.), Los Angeles, CA.

Address correspondence and reprint requests to Dr. William W. Sutherling, Huntington Medical Research Institutes, 10 Pico, Pasadena, CA 91105 sutherling{at}msn.com

Background: Magnetic source imaging (MSI) is used routinely in epilepsy presurgical evaluation and in mapping eloquent cortex for surgery. Despite increasing use, the diagnostic yield of MSI is uncertain, with reports varying from 5% to 35%. To add benefit, a diagnostic technique should influence decisions made from other tests, and that influence should yield better outcomes. We report preliminary results of an ongoing, long-term clinical study in epilepsy, where MSI changed surgical decisions.

Methods: We determined whether MSI changed the surgical decision in a prospective, blinded, crossover-controlled, single-treatment, observational case series. Sixty-nine sequential patients diagnosed with partial epilepsy of suspected neocortical origin had video-EEG and imaging. All met criteria for intracranial EEG (ICEEG). At a surgical conference, a decision was made before and after presentation of MSI. Cases where MSI altered the decision were noted.

Results: MSI gave nonredundant information in 23 patients (33%). MSI added ICEEG electrodes in 9 (13%) and changed the surgical decision in another 14 (20%). Based on MSI, 16 patients (23%) were scheduled for different ICEEG coverage. Twenty-eight have gone to ICEEG, 29 to resection, and 14 to vagal nerve stimulation, including 17 where MSI changed the decision. Additional electrodes in 4 patients covered the correct: hemisphere in 3, lobe in 3, and sublobar ictal onset zone in 1. MSI avoided contralateral electrodes in 2, who both localized on ICEEG. MSI added information to ICEEG in 1.

Conclusion: Magnetic source imaging (MSI) provided nonredundant information in 33% of patients. In those who have undergone surgery to date, MSI added useful information that changed treatment in 6 (9%), without increasing complications. MSI has benefited 21% who have gone to surgery.

Abbreviations: 2nd STEP = changed second step; ADD = MSI decision to add electrodes; BiF = bifrontal; Bil Uni = bilateral to unilateral; Change ICEEG = MSI changed the ICEEG decision as indicated; Class = postoperative outcome class; Dec VNS = declined surgery and had VNS; Decl = declined ICEEG and surgery; Defr = deferred surgery, pending ICEEG; ECoG = electrocorticography; F = frontal; FU = postoperative follow-up after focal excisional surgery; ICEEG = intracranial EEG; ICEEG Loc = intracranial EEG localization; ICEEG VNS = MSI changed decision from ICEEG to VNS; LAT = left anterior temporal lobectomy; LF = left frontal; LT = left temporal; LTm = left mesial temporal; LTml = left temporal both mesial and lateral; LTps = left temporal lateral posterior; MSI = magnetic source imaging; MSI Lat = MSI lateralization; MSI Lob = MSI lobar localization; MSI Loc = MSI sublobar localization; Op = surgical intervention; Pdg-Surg = pending excisional surgery; Pdg-VNS = pending VNS; RAT = right anterior temporal lobectomy; RC = right central; Red % = percentage reduction of seizures by surgery; Remis = spontaneous remission of seizures, no surgery; RF = right frontal focal excision; RFp = right frontopolar focal excision; ROp = right opercular; ROpRT = right opercular and right temporal regional ICEEG onset and multilobar resection; RTm = right mesial temporal; RTml = right temporal both mesial and lateral; T = temporal; VEEG = video-EEG; VNS = vagal nerve stimulation.

Supplemental data at www.neurology.org.

Supported by Public Health Service grants R01 NS20806 from the National Institute of Neurological Diseases and Stroke, S10-RR13276 from the National Center for Research Resources, the Zeilstra Foundation, and the Norris Foundation.

Disclosure: The authors report no disclosures.

Received January 9, 2007. Accepted in final form June 13, 2008.

This article has been cited by other articles:

				E. Asano, C. Juhasz, A. Shah, S. Sood, and H. T. Chugani Role of subdural electrocorticography in prediction of long-term seizure outcome in epilepsy surgery Brain, April 1, 2009; 132(4): 1038 - 1047. [Abstract] [Full Text] [PDF]