MEG coherence imaging compared to electrocortical recordings from NeuroPace implants to determine the location of ictal onset in epilepsy patients J.E. Moran a, ⁎ , S.M. Bowyer a , A. Manoharan a , K.M. Mason a , N. Tepley a , B.J. Smith a , G.L. Barkley a , D. Greene b , M. Morrell b a Neuromagnetism Laboratory, Henry Ford Hospital, Detroit, MI, USA b NeuroPace, CA, USA Abstract. NeuroPace has developed an experimental therapy for epilepsy that utilizes intracranial electrodes (subdural and depth) bipolar electrode pairs to monitor key epileptic network sites for the onset of seizure. When the beginning of a seizure is detected, a sequence of high frequency electric stimuli is delivered to one or more of the electrode pairs to disrupt the abnormal network activity. Thus, for both detection and treatment, it is important the electrodes are at sites of high epileptic network connectivity. Epileptic network connectivity of a cortical site can be quantified by the average coherence with other sites in the epileptic network. In this paper, MEG coherence imaging is used to generate whole brain images of epileptic network connectivity and study the relationship between seizure reduction and electrode placement. © 2007 Elsevier B.V. All rights reserved. Keywords: MEG; Coherence; NeuroPace; Epilepsy; Networks 1. Introduction Epilepsy is characterized by abnormal brain network connectivity and abnormal focal inputs to the network. Abnormal focal brain activity and network responses are attenuated by drug therapy and surgery is sometimes used to remove significant focal inputs. Alternatively, using an implanted NeuroPace device, intracranial bipolar electrode pairs monitor epileptic International Congress Series 1300 (2007) 673 – 676 www.ics-elsevier.com ⁎ Corresponding author. MEG Laboratory, 2799 W. Grand Blvd., CFP 79, Detroit, MI 48202-2689, USA. Tel.: +1 313 916 1075; fax: +1 313 916 0526. E-mail address: moran@neurnis.neuro.hfh.edu (J.E. Moran). 0531-5131/ © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.ics.2007.03.004