Table of Contents
Epilepsy Research and Treatment
Volume 2016, Article ID 3581358, 8 pages
http://dx.doi.org/10.1155/2016/3581358
Research Article

Hippocampography Guides Consistent Mesial Resections in Neocortical Temporal Lobe Epilepsy

1Section of Neurology, Department of Internal Medicine, Health Sciences Centre, University of Manitoba, Winnipeg, MB, Canada
2Clinical Neurophysiology, Beaumont Hospital, Dublin, Ireland
3Epilepsy Service, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
4Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA

Received 2 April 2016; Revised 27 June 2016; Accepted 14 August 2016

Academic Editor: Roy G. Beran

Copyright © 2016 Marcus C. Ng et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background. The optimal surgery in lesional neocortical temporal lobe epilepsy is unknown. Hippocampal electrocorticography maximizes seizure freedom by identifying normal-appearing epileptogenic tissue for resection and minimizes neuropsychological deficit by limiting resection to demonstrably epileptogenic tissue. We examined whether standardized hippocampal electrocorticography (hippocampography) guides resection for more consistent hippocampectomy than unguided resection in conventional electrocorticography focused on the lesion. Methods. Retrospective chart reviews any kind of electrocorticography (including hippocampography) as part of combined lesionectomy, anterolateral temporal lobectomy, and hippocampectomy over 8 years . Patients were divided into mesial (i.e., hippocampography) and lateral electrocorticography groups. Primary outcome was deviation from mean hippocampectomy length. Results. Of 26 patients, fourteen underwent hippocampography-guided mesial temporal resection. Hippocampography was associated with 2.6 times more consistent resection. The range of hippocampal resection was 0.7 cm in the mesial group and 1.8 cm in the lateral group (). 86% of mesial group versus 42% of lateral group patients achieved seizure freedom (). Conclusions. By rationally tailoring excision to demonstrably epileptogenic tissue, hippocampography significantly reduces resection variability for more consistent hippocampectomy than unguided resection in conventional electrocorticography. More consistent hippocampal resection may avoid overresection, which poses greater neuropsychological risk, and underresection, which jeopardizes postoperative seizure freedom.