Presurgical thalamocortical connectivity is associated with response to vagus nerve stimulation in children with intractable epilepsy

Publication date: Available online 22 September 2017 Source:NeuroImage: Clinical Author(s): George M. Ibrahim, Priya Sharma, Ann Hyslop, Magno R. Guillen, Benjamin R. Morgan, Simeon Wong, Taylor Abel, Lior Elkaim, Iahn Cajigas, Ashish H. Shah, Aria Fallah, Alexander G. Weil, Nolan Altman, Byron Bernal, Santiago Medina, Elysa Widjaja, Prasanna Jayakar, John Ragheb, Sanjiv Bhatia Although chronic vagus nerve stimulation (VNS) is an established treatment for medically-intractable childhood epilepsy, there is considerable heterogeneity in seizure response and little data are available to pre-operatively identify patients who may benefit from treatment. Since the therapeutic effect of VNS may be mediated by afferent projections to the thalamus, we tested the hypothesis that intrinsic thalamocortical connectivity is associated with seizure response following chronic VNS in children with epilepsy. Twenty-one children (ages 5–21years) with medically-intractable epilepsy underwent resting-state fMRI prior to implantation of VNS. Ten received sedation, while 11 did not. Whole brain connectivity to thalamic regions of interest was performed. Multivariate generalized linear models were used to correlate resting-state data with seizure outcomes. A supervised support vector machine (SVM) algorithm was used to classify response to chronic VNS on the basis of intrinsic connectivity, while adjusting for age and sedation status. Of the 21 subjects, 11 (52%) had 50% or gr...
Source: NeuroImage: Clinical - Category: Radiology Source Type: research