Use of a Wireless Video-EEG System to Monitor Epileptiform Discharges Following Lateral Fluid-Percussion Induced Traumatic Brain Injury

Abstract

The lateral fluid percussion injury (FPI) model is well established and has been used to study TBI and post-traumatic epilepsy (PTE). However, considerable variability has been reported for the specific parameters used in different studies that have employed this model, making it difficult to harmonize and interpret the results between laboratories. For example, variability has been reported regarding the size and location of the craniectomy, how the Luer lock hub is placed relative to the craniectomy, the atmospheric pressure applied to the dura and the duration of the pressure pulse. Each of these parameters can impact injury severity, which directly correlates with the incidence of PTE. This has been manifested as a wide range of mortality rates, righting reflex times and incidence of convulsive seizures reported. Here we provide a detailed protocol for the method we have used to help facilitate harmonization between studies. We used FPI in combination with a wireless EEG telemetry system to continuously monitor for electrographic changes and detect seizure activity. FPI is induced by creating a 5 mm craniectomy over the left hemisphere, between the Bregma and Lambda and adjacent to the lateral ridge. A Luer lock hub is secured onto the skull over the craniectomy. This hub is connected to the FPI device, and a 20-millisecond pressure pulse is delivered directly to the intact dura through pressure tubing connected to the hub via a twist lock connector. Following recovery, rats are re-anesthetized to remove the hub. Five 0.5 mm, stainless steel EEG electrode screws are placed in contact with the dura through the skull and serve as four recording electrodes and one reference electrode. The electrode wires are collected into a pedestal connector which is secured into place with bone cement. Continuous video/EEG recordings are collected for up to 4 weeks post TBI.

Modelling epilepsy in the mouse: challenges and solutions

“…However, rats with clinically relevant mutations have also been studied ( Ohmori et al, 2020 ). Diverse EEG setups have been developed for both tethered ( Medlej et al, 2019 ) and wireless ( McGuire et al, 2019 ) EEG in rats, and ex vivo brain slice preparations can be used to study seizure susceptibility ( Accardi et al, 2018 ) and epileptogenesis ( Dyhrfjeld-Johnsen et al, 2010 ), and to screen ASDs ( Hill et al, 2010 ).…”

Cu‐Zn SOD suppresses epilepsy in pilocarpine‐treated rats and alters SCN2A/Nrf2/HO‐1 expression

“…Progression of epilepsy often leads to brain dysfunction, limb convulsions, and behavioural disorders or sensory disturbances, which seriously disturb patients • 651 [21,22]. According to the literature, development of epilepsy is known to result in the increase of oxidative stress, which leads to excessive neurotransmitter excitation, neuronal apoptosis or metabolic structural damage [23,24]. The present study found that Cu-Zn SOD suppresses epilepsy and alters the NaV1.2/Nrf2/ HO-1 axis.…”

Differential patterns of change in brain connectivity resulting from severe traumatic brain injury

“…Adult, male, Wistar rats (300-350g) were obtained from Charles River Laboratories (Wilmington, MA) and single housed in a 12-hour light/dark schedule with ad libitum access to food and water. The lateral fluid percussion injury procedure was performed as we have previously published (McGuire et al, 2019).…”