Functional Connectivity Of Hippocampus Head Correlated With Epileptic Episodes Of Patients With Mesial Tempo Rallobe Epilepsy

Objective:Increasing research has examined the alterations of functional connectivity (FC) in patients with mesial temporal lobe epilepsy (mTLE) by using resting state functional connectivity magnetic resonance imaging (rs-fcMRI). The present study is to investigate and compare the alterations of healthy side hippocampal functional connectivity in right and left mTLE-HS (hippocampal sclerosis).Methods:22patients diagnosed as having left mTLE-HS and right mTLE-HS by the comprehensive evaluation of detailed clinical history and neurological examinations, scalp EEG with sphenoidal electrodes, and conventional magnetic resonance imaging (cMRI) were enrolled in this study. These patients received rs-fcMRI scans and are compared to12age-matched healthy volunteers for investigating the healthy side hippocampal connectivity and examine brain regions correlated with the number of seizures.Results:The alterations of FC in left mTLE-HS group include ipsilateral hippocampal and extra-hippocampal regions mainly in language areas, while only extra-hippocampal regions including visual areas were detected in right mTLE-HS group. The FC of healthy side hippocampal head (HH) connectivity to the other brian regions mainly displayed decreased FC with the increased number of seizures in mTLE-HS. Meanwhile lingual gyrus showed increased FC with the increased number of seizures in both of two types of mTLE-HS.Conclusion:Language areas of HH networks in left mTLE showed disrupted, while visual areas of HH networks in right mTLE showed impaired. We suggest that the influence of ipsilateral impaired hippocampus induce a bilateral impairment of the neuroanatomical circuits subserving verbal and visual memory. The involved brain regions in right mTLE-HS group were wider than left mTLE-HS group.