title: Increased Expression of Epileptiform Spike/Wave Discharges One Year after Mild, Moderate, or Severe Fluid Percussion Brain Injury in Rats.
abstract: In this study, we describe increased expression of cortical epileptiform spike/wave discharges (SWD) in rats one year after mild, moderate, or severe fluid percussion traumatic brain injury (fpTBI). Groups of rats consisted of animals that had received mild, moderate, or severe fpTBI, or sham operation one year earlier than electrocorticography (ECoG) recordings. In addition, we included a group of age-matched naïve animals. ECoG was recorded from awake animals using epidural electrodes implanted on the injured hemisphere (right), sham-operated hemisphere (right), or right hemisphere in naïve animals. The SWDs were detected automatically using Fast Fourier Transformation and a novel algorithm for comparing changes in spectral power to control (nonepileptical) ECoG. The fpTBI resulted in increased expression of SWDs one year after injury compared with sham-operated or naïve animals. The number of SWD-containing ECoG epochs recorded in a 1 h recording session were: naïve 12.9 ± 10.3, n = 8, sham 23.6 ± 8.2, n = 10, mild TBI 78.9 ± 23.9, n = 10, moderate TBI 61.3 ± 32.5, n = 12, severe TBI 72.5 ± 28.3, n = 11 (mean ± standard error of the mean). Increased expression of SWDs was not related to injury severity. SWDs were observed to a lesser extent even in sham-operated and naïve animals. The data indicate that fpTBI exacerbates expression of SWDs in the rat and that this increase may be observed at least one year after injury. As others have discussed, the spontaneous occurrence of these epileptiform events in rodents limits the use of this model for investigations of acquired epilepsy, at least of the nonconvulsive type, after TBI.
authors.affiliation: 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.|2 Department of Neurology, University of Miami Miller School of Medicine , Miami, Florida.|3 Department of Neuroscience Program, University of Miami Miller School of Medicine , Miami, Florida.
authors.forename: Thomas
authors.initials: T
authors.lastname: Sick
authors.affiliation: 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.
authors.forename: Joseph
authors.initials: J
authors.lastname: Wasserman
authors.affiliation: 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.
authors.forename: Amade
authors.initials: A
authors.lastname: Bregy
authors.affiliation: 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.
authors.forename: Justin
authors.initials: J
authors.lastname: Sick
authors.affiliation: 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.|2 Department of Neurology, University of Miami Miller School of Medicine , Miami, Florida.|3 Department of Neuroscience Program, University of Miami Miller School of Medicine , Miami, Florida.|4 Department of Neurological Surgery, University of Miami Miller School of Medicine , Miami, Florida.
authors.forename: W Dalton
authors.initials: WD
authors.lastname: Dietrich
authors.affiliation: 1 The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine , Miami, Florida.|2 Department of Neurology, University of Miami Miller School of Medicine , Miami, Florida.|3 Department of Neuroscience Program, University of Miami Miller School of Medicine , Miami, Florida.|4 Department of Neurological Surgery, University of Miami Miller School of Medicine , Miami, Florida.|5 Bruce W. Carter Department of Veterans Affairs Medical Center , Miami, Florida.|6 Center for Computational Science, University of Miami , Miami, Florida.
authors.forename: Helen M
authors.initials: HM
authors.lastname: Bramlett
mesh_terms: D000818:Animals; D000070642:Brain Injuries, Traumatic / Q000150:complications / Q000503:physiopathology*; D000069280:Electrocorticography; D004827:Epilepsy / Q000209:etiology / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley
keywords: electrocorticogram; electroencephalogram; epilepsy; fluid percussion; nonconvulsive seizures; spike wave discharges; traumatic brain injury