There is Greater Interictal Band Related Local Functional Connectivity in Patients with Excellent Outcome to Surgery in Comparison to those with Poorer Outcome
Abstract number :
2.058
Submission category :
1. Translational Research: 1C. Human Studies
Year :
2017
Submission ID :
350124
Source :
www.aesnet.org
Presentation date :
12/3/2017 3:07:12 PM
Published date :
Nov 20, 2017, 11:02 AM
Authors :
Hitten P. Zaveri, Yale University; Steven Pincus, 990 Moose Hill Road, Guilford, CT; Irina I. Goncharova, Yale University; Reshma Munbodh, 500 Prospect Street, New Haven, CT; Rafeed Alkawadri, Yale University; Jason L. Gerrard, Yale University; Robert B.
Rationale: To determine the band-related local functional connectivity (BRLFC) of the seizure onset area (SOA) and the peri-SOA in patients with excellent outcome (EO) and poorer outcome (PO) to epilepsy surgery. Methods: This study was conducted on 18 unselected adult patients with intractable epilepsy who underwent intracranial EEG (icEEG) monitoring, 13 of whom underwent subsequent surgery. Intracranial EEG electrode contacts were located from post-implantation CT and MR images and registered to the MRI of a standard brain to allow interpretation of results from all patients in the same space. A 1 hr icEEG epoch, recorded during wake and removed in time from seizure occurrence, was studied. Coherence was estimated for all pairs of electrode contacts ipsilateral to the SOA in delta, theta, alpha, beta, gamma and a high frequency band. The BRLFC of each electrode contact was estimated as the average band-related coherence between it and all electrode contacts within a specified spatial window. Results: The average BRLFC was significantly (p < 0.05) non-zero, significantly greater in EO patients in comparison to PO patients, and demonstrated an inverse relationship with distance from the SOA. The contacts ipsilateral to the SOA were separated into three sets based on radial distance to the SOA: (1) S: SOA contacts, (2) P: all contacts within 5 cm of the SOA but not including SOA contacts, (3) D: all contacts from 6 to 10 cm of the SOA. The mean BRLFC for all contacts in each of these three sets was calculated as well as the ratios of the mean values of BRLFC for S, P and D. The most pronounced significant differences in these values were observed between P and D in gamma BRLFC. Conclusions: There is greater BRLFC in EO patients in comparison to PO patients. Further, a graded relationship exists between BRLFC and distance to the SOA, for specific frequency bands, such that electrode contacts with the greatest connectivity are in the SOA or in the immediate peri-SOA and those with the lowest connectivity are at a distance of several cm from the SOA.
Translational Research