A method for focused ultrasound (FUS) neuromodulation with simultaneous electroencephalogram recordings in awake, head-fixed mice with temporal lobe epilepsy

Abstract

Transcranial focused ultrasound (FUS) may be a promising neuromodulation technology for treating people with epilepsy whose seizures are drug resistant. Prior studies have shown seizure suppression in animal studies using FUS. However, most of these studies were performed in evoked seizure models and not in animal models of epilepsy. Evoked seizure models do not exhibit the pathophysiology of epilepsy and do not exhibit spontaneous recurrent seizures, which define epilepsy. For translation to humans, there is a critical need to determine the specific FUS stimulation parameters that reduce spontaneous recurrent seizures in a chronic disease model of epilepsy. To achieve this goal, we developed and optimized an approach to determine the effects of ultrasonic stimulation on metrics of seizure-like events (SLEs) in awake, head-fixed mice within the intrahippocampal kainate (IHK) mouse model of temporal lobe epilepsy (TLE). A proof-of-principle study demonstrated that two target (bilateral and contralateral to the kainic acid injection site) stimulation conditions and two FUS parameter sets (low and high pressure) could be combined with the ability to simultaneously record hippocampal electroencephalograms. We also provide a method for analysis of the effects of FUS stimulation on the metrics of SLEs (interevent duration, SLE duration, and spike frequency).