Incidence Of Post-traumatic Epilepsy Research Articles

Risk of epilepsy after traumatic brain injury: a nationwide Norwegian matched cohort study.

Post-traumatic epilepsy (PTE) is a well-known complication of traumatic brain injury (TBI). Although several risk factors have been identified, prediction of PTE is difficult. Changing demographics and advances in TBI treatment may affect the risk of PTE. Our aim was to provide an up-to-date estimate of the incidence of PTE by linking multiple nationwide registers. Patients with TBI admitted to hospital 2015-2018 were identified in the Norwegian Trauma Registry and matched to trauma-free controls on sex and birth year according to a matched cohort design. They were followed up for epilepsy in nationwide registers 2015-2020. Cumulative incidence of epilepsy in TBI patients and controls was estimated taking competing risks into account. Analyses stratified by the Abbreviated Injury Scale (AIS) severity score, Glasgow Coma Scale score and age were conducted for the TBI group. Occurrence of PTE in different injury types was visualized using UpSet plots. In total, 8,660 patients and 84,024 controls were included in the study. Of the patients, 3,029 (35%) had moderate to severe TBI. The cumulative incidence of epilepsy in the TBI group was 3.1% (95% Confidence Interval [CI] 2.8-3.5%) after 2 years and 4.0% (3.6-4.5%) after 5 years. Corresponding cumulative incidences in the control group were 0.2% (95% CI 0.2-0.3%) and 0.5% (0.5-0.6%). The highest incidence was observed in patients with severe TBI according to AIS (11.8% [95% CI 9.7-14.4%] after 2 years and 13.2% [10.8-16.0%] after 5 years) and in patients >40 years of age. Patients with TBI have significantly higher risk of developing epilepsy compared to population controls. However, PTE incidence following moderate-severe TBI was notably lower than what has been reported in several previously published studies.

A role of dentate gyrus mechanistic target of rapamycin activation in epileptogenesis in a mouse model of posttraumatic epilepsy.

The mechanistic target of rapamycin (mTOR) pathway has been implicated in promoting epileptogenesis in animal models of acquired epilepsy, such as posttraumatic epilepsy (PTE) following traumatic brain injury (TBI). However, the specific anatomical regions and neuronal populations mediating mTOR's role in epileptogenesis are not well defined. In this study, we tested the hypothesis that mTOR activation in dentate gyrus granule cells promotes neuronal death, mossy fiber sprouting, and PTE in the controlled cortical impact (CCI) model of TBI. An adeno-associated virus (AAV)-Cre viral vector was injected into the hippocampus of Rptorflox/flox (regulatory-associated protein of mTOR) mutant mice to inhibit mTOR activation in dentate gyrus granule cells. Four weeks after AAV-Cre or AAV-vehicle injection, mice underwent CCI injury and were subsequently assessed for mTOR pathway activation by Western blotting, neuronal death, and mossy fiber sprouting by immunopathological analysis, and posttraumatic seizures by video-electroencephalographic monitoring. AAV-Cre injection primarily affected the dentate gyrus and inhibited hippocampal mTOR activation following CCI injury. AAV-Cre-injected mice had reduced neuronal death in dentate gyrus detected by Fluoro-Jade B staining and decreased mossy fiber sprouting by ZnT3 immunostaining. Finally, AAV-Cre-injected mice exhibited a decrease in incidence of PTE. mTOR pathway activation in dentate gyrus granule cells may at least partly mediate pathological abnormalities and epileptogenesis in models of TBI and PTE. Targeted modulation of mTOR activity in this hippocampal network may represent a focused therapeutic approach for antiepileptogenesis and prevention of PTE.

Incidence and predictors of posttraumatic epilepsy and cognitive impairment in patients with traumatic brain injury: A retrospective cohort study in Malaysia.

Posttraumatic epilepsy (PTE) significantly impacts morbidity and mortality, yet local PTE data remain scarce. In addition, there is a lack of evidence on cognitive comorbidity in individuals with PTE in the literature. We sought to identify potential PTE predictors and evaluate cognitive comorbidity in patients with PTE. A 2-year retrospective cohort study was employed, in which adults with a history of admission for traumatic brain injury (TBI) in 2019 and 2020 were contacted. Three hundred one individuals agreed to participate, with a median follow-up time of 30.75 months. The development of epilepsy was ascertained using a validated tool and confirmed by our neurologists during visits. Clinical psychologists assessed the patients' cognitive performance. The 2-year cumulative incidence of PTE was 9.3% (95% confidence interval [CI] 5.9-12.7). The significant predictors of PTE were identified as a previous history of brain injury [hazard ratio [HR] 4.025, p = .021], and intraparenchymal hemorrhage (HR: 2.291, p = .036), after adjusting for other confounders. TBI patients with PTE performed significantly worse on the total ACE-III cognitive test (73.5 vs 87.0, p = .018), CTMT (27.5 vs 33.0, p = .044), and PSI (74.0 vs 86.0, p = .006) than TBI patients without PTE. A significantly higher percentage of individuals in the PTE group had cognitive impairment, compared to the non-PTE group based on ACE-III (53.6% vs 46.4%, p = .001) and PSI (70% vs 31.7%, p = .005) scores at 2 years post-TBI follow-up. This study emphasizes the link between TBI and PTE and the chance of developing cognitive impairment in the future. Clinicians can target interventions to prevent PTE by identifying specific predictors, which helps them make care decisions and develop therapies to improve patients' quality of life.

Hospital-acquired infections as a risk factor for post-traumatic epilepsy: A registry-based cohort study.

Hospital-acquired infections are a common complication for patients with moderate or severe traumatic brain injury (TBI), contributing to morbidity and mortality. As infection-mediated immune responses can predispose towards epilepsy, we hypothesized that post-injury hospital-acquired infections increase the risk of post-traumatic epilepsy (PTE). A retrospective cohort study of adults with moderate to severe TBI was conducted using data from the Victorian State Trauma Registry in Australia. Infections were identified from the International Statistical Classification of Diseases and Related Health Problems 10th Revision-Australian Modification (ICD-10-AM) codes, and diagnosis of PTE was determined by the Glasgow Outcome Scale - Extended questionnaire regarding epileptic fits at 24 months follow-up. Of all TBI patients (n = 15 152), 24% had evidence of having had any type of infection, with the most common being pneumonia, urinary tract, and respiratory infections. Of those who responded to the PTE question at 24 months (n = 1361), 11% had developed PTE. Univariable analysis found that the incidence of PTE was higher in patients who had any type of infection compared to patients without an infection (p < 0.001). After adjustment for covariates associated with both development of PTE and risk of infection, multivariable analysis found a solid association between infection and PTE (adjusted RR = 1.59; 95% CI: 1.11-2.28; p = 0.011). Having any type of complicating infection acquired during admission was also associated with poor GOSE outcomes at subsequent follow-ups (adjusted OR = 0.20; 95% CI: 0.11-0.35, p < 0.001). These findings suggest that hospital-acquired infections contribute to PTE development after TBI. Future investigation into infections as a modifiable target to reduce poor outcomes after TBI is warranted. Hospital-acquired infections are common in patients with traumatic brain injuries. A database study of adults with moderate or severe brain injuries in Australia examined whether these infections are associated with the development of epilepsy after a brain injury. 24% of patients had infections, with pneumonia and urinary tract infections being the most common. Of those surveyed 2 years after the injury, 11% developed post-traumatic epilepsy. Patients with infections had a significantly higher risk of epilepsy, even when accounting for other known risk factors, and infections were also linked to poor outcomes more broadly. The study suggests that preventing hospital-acquired infections could be a crucial target for improving outcomes after traumatic brain injuries.

Insights into epileptogenesis from post-traumatic epilepsy.

Post-traumatic epilepsy (PTE) accounts for 5% of all epilepsies. The incidence of PTE after traumatic brain injury (TBI) depends on the severity of injury, approaching one in three in groups with the most severe injuries. The repeated seizures that characterize PTE impair neurological recovery and increase the risk of poor outcomes after TBI. Given this high risk of recurrent seizures and the relatively short latency period for their development after injury, PTE serves as a model disease to understand human epileptogenesis and trial novel anti-epileptogenic therapies. Epileptogenesis is the process whereby previously normal brain tissue becomes prone to recurrent abnormal electrical activity, ultimately resulting in seizures. In this Review, we describe the clinical course of PTE and highlight promising research into epileptogenesis and treatment using animal models of PTE. Clinical, imaging, EEG and fluid biomarkers are being developed to aid the identification of patients at high risk of PTE who might benefit from anti-epileptogenic therapies. Studies in preclinical models of PTE have identified tractable pathways and novel therapeutic strategies that can potentially prevent epilepsy, which remain to be validated in humans. In addition to improving outcomes after TBI, advances in PTE research are likely to provide therapeutic insights that are relevant to all epilepsies.

Initial clinical evidence on biperiden as antiepileptogenic after traumatic brain injury-a randomized clinical trial.

There is currently no efficacious intervention for preventing post-traumatic epilepsy (PTE). Preclinical studies support the potential use of anticholinergics for this condition. The purpose of this study was to evaluate the effects of biperiden as an intervention for preventing PTE. A randomized, double-blinded clinical trial was conducted at HC/FMUSP between 2018-2022. Adults with acute traumatic brain injury (TBI) were randomly assigned to receive biperiden or placebo, for 10 days. The primary outcome was the incidence of PTE while the secondary outcomes included the frequency of seizures, the frequency of any adverse events and mortality after 24 months. The study was powered at a planned enrolment of 132 patients. The trial began in January 2018 and was halted by researchers on March 2020 (and terminated in December 2022) in the face of the global COVID-19 pandemic. Overall, 123 participants were randomized and 112 contributed with data for modified mITT analysis, being that 61 (49.5%) participants completed the 24-month follow-up consult. Data analysis indicated lack of evidence of biperiden for either, the incidence of post-traumatic epilepsy (2.6, 95%CI, 0.65-10.57; p = 0.170) or the mortality rate (1.57, 95%CI, 0.73-3.38; p = 0.248). The frequency of late post-traumatic seizures was higher for biperiden group (2.03, 95%CI = 0.912-3.1597; p <0.001). The present study suggests that there was insufficient evidence regarding the effect of biperiden in preventing PTE after TBI, which underpins the need for larger studies. Clinical trial registration: ClinicalTrials.gov, identifier: NCT01048138.

The Cumulative Incidence of Post-Traumatic Epilepsy After Mild Traumatic Brain Injury: A Systematic Review and Individual Participant Data Meta-Analysis Protocol.

A precise understanding of the latency to post-traumatic epilepsy (PTE) following a traumatic brain injury (TBI) is necessary for optimal patient care. This precision is currently lacking despite a surprising number of available data sources that could address this pressing need. Following guidance from the Cochrane Collaboration and Joanna Briggs Institute, we conduct a systematic review to address the research questions: What is the cumulative incidence of PTE following mild TBI (mTBI; concussion), and what is the distribution of the latency to onset? We designed a comprehensive search of medical databases and gray literature sources. Citations will be screened on both abstract and full-text levels, independently and in duplicate. Studies will be evaluated for risk of bias independently and in duplicate using published instruments specific to incidence/prevalence studies. Data will be abstracted independently and in duplicate using piloted extraction forms. Disagreements will be resolved by consensus or third-party adjudication. Evidence synthesis will involve pairwise and individual participant data meta-analysis with heterogeneity explored via a set of predetermined subgroups. The robustness of the findings will be subjected to sensitivity analyses based on the risk of bias, outlier studies, and mTBI definitional criteria. The overall certainty in the estimates will be reported using GRADE (Grading of Recommendations, Assessment, Development, and Evaluations). This protocol presents an innovative and impactful approach to build on the growing body of knowledge surrounding post-mTBI PTE. Through a precise understanding of the latency period, this study can contribute to early detection, tailored interventions, and improved outcomes, leading to a substantial impact on patient care and quality of life.

Clinical characteristics and associated factors of posttraumatic epilepsy after traumatic brain injury in children: A retrospective case-control study

BackgroundTraumatic brain injury (TBI) affects approximately 69 million individuals annually, often resulting in well-documented complications such as epilepsy. Although numerous studies have been performed on posttraumatic epilepsy (PTE) in adults over the past decade, research on chronic consequences of TBI in children remains limited. Herein, we retrospectively assessed children who had experienced moderate to severe TBI to determine their clinical characteristics and identify associated factors associated with the development of PTE in the pediatric population. MethodsThe study population comprised children aged 0–18 years who had experienced moderate to severe TBI and underwent treatment at the Children's Hospital of Chongqing Medical University between 2011 and 2021. They were categorized into two groups: the PTE group, comprising individuals diagnosed with PTE within a one-year follow-up period, and the nPTE group, consisting of those who did not develop PTE during the same timeframe. The primary objective was to investigate the clinical characteristics and identify related associated factors. The relationship between various clinical factors and the incidence of PTE was assessed through univariate and multivariate logistic regression. ResultsA total of 132 patients were assessed. Most participants were male (65%) and the age distribution skewed towards younger children, with a median age of 41.0 months (interquartile range: 45.3). Upon their last clinical visit, 64 children (49%) were diagnosed with PTE. Notably, the first posttraumatic seizure predominantly occurred within the first week following the traumatic event. Further analyses revealed that increasing injury severity, as indicated by a lower Glasgow Coma Scale (GCS) score (odds ratio [OR]: 0.78, 95% confidence interval [CI]: 0.54–1.12, p= 0.018), a contusion load ≥3 (OR: 8.1, 95% CI: 2.3–28.9, p= 0.001), immediate posttraumatic seizures (IPTS) (OR: 8.9, 95% CI: 2.5–31.2, p < 0.001), and early posttraumatic seizures (EPTS) (OR: 54, 95% CI: 11–276, p < 0.001), were all significantly associated with a higher risk of developing PTE. ConclusionThis study highlights that the onset of PTE was associated with the markers of injury severity or PTS and identified GCS scores, contusion loads of ≥3, IPTS, and EPTS as independent associated factors significantly associated with the development of PTE.

The Role of Decreased Levels of Neuronal Autophagy in Increased Susceptibility to Post-traumatic Epilepsy.

Post-traumatic epilepsy (PTE) caused by mild TBI (mild traumatic brain injury, mTBI) has a high incidence and poor prognosis, but its mechanisms are unclear. Herein, we investigated the role of reduced levels of neuronal autophagy during the latency period in the increased susceptibility to PTE. In the study, a gentle whole-body mechanical trauma rat model was prepared using Noble-Collip drums, and the extent of injury was observed by cranial CT and HE staining of hippocampal tissue. The incidence of epilepsy and its seizure form were observed 7-90days after mTBI, and electroencephalography (EEG) was recorded during seizures in rats. Subcortical injection of non-epileptogenic dose of ferrous chloride (FeCl2) was used to observe the changes of PTE incidence after mTBI. Western blot and Real-time PCR were used to detect the level of autophagy in hippocampal cells at different time points during the latency period of PTE, and its incidence was observed after up-regulation of autophagy after administration of autophagy agonist-rapamycin. The results showed that mTBI was prepared by Noble-Collip drum, which could better simulate the clinical mTBI process. There was no intracerebral hemorrhage and necrosis in rats, no early-onset seizures, and the incidence of PTE after mTBI was 26.7%. The incidence of PTE was 56.7% in rats injected cortically with FeCl2 at a dose lower than the epileptogenic dose 48h after mTBI, and the difference was significant compared with no FeCl2 injection, suggesting an increased susceptibility to PTE after mTBI. Further study of neuronal autophagy during PTE latency revealed that autophagy levels were reduced, and the incidence of PTE was significantly reduced after administration of rapamycin to upregulate autophagy. Taken together, the decreased level of neuronal autophagy during the latency period may be a possible mechanism for the increased susceptibility to PTE after mTBI.

Incidence and risk factors of posttraumatic epilepsy following pediatric traumatic brain injury: A systematic review and meta-analysis.

Posttraumatic epilepsy (PTE) is a well-known chronic complication following traumatic brain injury (TBI). Despite some evidence that age at the time of injury may influence the likelihood of PTE, the incidence of PTE in pediatric populations remains unclear. We therefore conducted a systematic review to determine the overall reported incidence of PTE, and explore potential risk factors associated with PTE after pediatric TBI. A comprehensive literature search of the PubMed, Embase, and Web of Science databases was conducted, including randomized controlled trials and cohort studies assessing the incidence of PTE in TBI pediatric patients. We excluded studies with a sample size of <10 patients and those in which a pediatric cohort was not clearly discernable. The review was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We found that the overall incidence of PTE following pediatric TBI was 10% (95% confidence interval [CI]=5.9%-15%). Subgroup analysis of a small number of studies demonstrated that the occurrence of early seizures (cumulative incidence ratio [CIR]=7.28, 95% CI=1.09-48.4, p= .040), severe TBI (CIR=1.81, 95% CI=1.23-2.67, p< .001), and intracranial hemorrhage (CIR=1.60, 95% CI=1.06-2.40, p= .024) increased the risk of PTE in this population. Other factors, including male sex and neurosurgical intervention, were nonsignificantly associated with a higher incidence of PTE. In conclusion, PTE is a significant chronic complication following childhood TBI, similar to in the adult population. Further standardized investigation into clinical risk factors and management guidelines is warranted. PROSPERO ID# CRD42021245802.

121 Analysis of Post-traumatic Epilepsy After Severe Traumatic Brain Injury in a Modern Series Identifies an Increasing Incidence and Novel Risk Factors

INTRODUCTION: Post-traumatic epilepsy (PTE) accounts for 20% of symptomatic epilepsy with rates highest after severe Traumatic Brain Injury (TBI). PTE has not been well studied in modern cohorts and its risk factors are poorly understood. METHODS: We retrospectively reviewed severe TBI patients from a prospective database treated from 2002 through 2018 at a single level 1 trauma center, excluding those with alcohol withdrawal seizures, prior epilepsy, or death at discharge. Using definitions from the International League Against Epilepsy, a seizure was defined as a witnessed clinical event confirmed to be a seizure by the treating healthcare team or electroencephalography, and PTE as two or more seizures. We collected timing of seizures, follow up, demographic, clinical information, and Glasgow Outcomes Scale (GOS). Because more severe injury predisposes to both death and PTE, we developed a competing hazards model to identify independent predictors of PTE. RESULTS: We identified 393 patients after exclusions. The rate of early seizures within 7 days was 2.8% (11). The cumulative incidence of PTE was 11% by one year and 25% overall, with 29% of PTE patients requiring multiple anti-seizure medications.Patients with PTE had more severe injuries with higher rates of unreactive pupils, subdural hematomas, obliteration of the basal cisterns, skull fractures, Marshall CT classification, decompressive hemicraniectomies (DHC), lobectomies, and shunting, as well as increased length of stay (LOS), younger age, and intracranial infections (all p &lt; 0.01). Our adjusted model identified age (subdistribution hazard 0.75; 95% confidence interval [95% CI]: 0.62 – 0.93]), DHC (3.3; 95% CI: 2.0-5.5), lobectomy (2.2; 95% CI: 2.6 – 4.2), and infection (1.9; 95% CI: 1.1 – 3.3) as predictors of PTE. Patients with PTE had worse functional outcomes (GOS 1-3 versus 4-5) at 6, 12, and 24 months (p &lt; 0.03). CONCLUSION: The incidence of PTE after severe TBI is higher than historical cohorts suggest and continues to increase though fifteen years post-trauma. Patients with PTE have more severe injuries with worse functional outcomes.

DYNAMICS OF CLINICAL AND NEUROPHYSIOLOGICAL CHANGES AGAINST THE BACKGROUND OF COMPLEX MEDICAL THERAPY IN PATIENTS WITH POSTTRAUMATIC EPILEPSY WITH CONCOMITANT SOMATIC DISEASES

Posttraumatic epilepsy can be characterized as a variant of the consequences of craniocerebral trauma (CMT) with a leading epileptic syndrome, which is manifested, respectively, by systematically repeated epileptic seizures, most often of convulsive nature.The leading etiological factor of symptomatic epilepsy of young age is craniocerebral trauma, which takes 30-50% of all types of injuries in peace time. The incidence of post-traumatic epilepsy in cases of previously suffered traumatic brain injury ranges from 5 to 50%, according to numerous studies, and its course is often progredient. The problem of diagnosis and drug treatment of posttraumatic epilepsy remains one of the most difficult tasks of clinical neurology [1,3,5].

Incidence of post traumatic epilepsy in Khartoum State, Sudan between the period of December 2018 to January 2020

Epilepsy is one of the commonest neurological disorders. It has a strong association with trauma to the brain, constituting of 5% of epilepsy cases. To determine the prevalence of post-traumatic epilepsy among Sudanese patients and to demonstrate the relation between traumatic brain injury and occurrence of epilepsy.

Preventing epilepsy after traumatic brain injury: A propensity score analysis

Background:Due to the potential consequences of post-traumatic epilepsy (PTE) exacerbating secondary injury following traumatic brain injury (TBI), the use of antiepileptic drugs (AEDs) is an accepted option for seizure prophylaxis. However, there is only a paucity of data that can be found regarding outcomes surrounding the use of AEDs. The purpose of this retrospective study is to evaluate whether the prophylactic administration of AEDs significantly decreased the incidence of PTE, when considering the severity of TBI.Methods:All trauma patients who had been newly diagnosed with TBI from January 1, 2010 to December 31, 2017 were retrospectively analyzed. Statistical comparisons were made using the chi-square test, Mann-Whitney U test, and Cox regression modeling. After excluding any exposed subjects with no appropriate match, patients who had received AED prophylaxis were matched by propensity score with those who did not receive AEDs. All of the TBI populations were followed up until June 30, 2018.Results:We identified 1316 patients who met the inclusion and exclusion criteria in our matched cohort through their propensity scores, where 138 patients had been receiving prophylactic AEDs and 138 patients had not. Baseline characteristics were similar in gender, age, Glasgow Coma Scale (GCS) scores, and risk factors of PTE including skull fracture, chronic alcoholism, subdural hematoma, epidural hematoma, and intracerebral hematoma. After adjusting for those risk factors, the relative incidence of seizure was not statistically significant in either of the groups (p = 0.566).Conclusion:In our cohort analysis, AED prophylaxis was ineffective in preventing seizures, as the rate of seizures was similar whether patients had been receiving the drugs or not. We therefore concluded that the benefits of routine prophylactic anticonvulsant therapy in patients with TBI need to be re-evaluated.

Epidemiology of traumatic brain injury-associated epilepsy in western China: An analysis of multicenter data

ObjectivesThis study aims to explore the probability of developing posttraumatic epilepsy (PTE) in the following 8 years after traumatic brain injury (TBI), the risk factors associated with PTE and its cumulative prevalence. MethodsThis is a retrospective follow-up study of patients with traumatic brain injury (TBI) discharged from the West China Hospital between January 1, 2011 and December 31, 2017, Chengdu Shang Jin Nan Fu Hospital and Sichuan Provincial People’s Hospital from January 1, 2013 to March 1, 2015. We used forward stepwise method to build the final multivariate cox proportional hazard regression model to obtain estimates of hazard ratio (HR) of PTE and 95% confidence intervals (CI). We also conducted Kaplan–Meier survival analysis to investigate the cumulative prevalence of PTE. ResultsThe cumulative incidence of PTE rose from 6.2% in one year to 10.6% in eight years. There were more male patients in PTE group and generally older. Besides, patients with PTE tended to have abnormal CT scan results. The risk factors of PTE were male (HR = 1.6, 95% CI: 1.1−2.2, P = 0.009), early posttraumatic seizures (HR = 2.9, 95% CI: 2.2−4.1, P < 0.001), TBI severity (moderate TBI: HR = 3.0, 95% CI: 1.8−5.0, P = 0.001; severe TBI: HR = 4.3, 95% CI: 2.3−7.6, P < 0.029), loss of consciousness (LOC) more than 30 min (30 min–24 h: HR = 1.8, 95% CI: 1.02−3.1, P = 0.041; >24 h: HR = 2.4, 95% CI: 1.4−2.4, P = 0.001), subdural hematoma (SDH) (HR = 1.9, 95% CI: 1.4−2.5, P < 0.001), brain contusion sites (frontal–temporal lobe: HR = 2.7, 95% CI: 1.9−3.9, P < 0.001; other sites: HR = 1.5, 95% CI: 1.01−2.3, P = 0.042) and cranial surgery (HR = 1.7, 95% CI: 1.3−2.3, P < 0.001). SignificanceThe probability of developing PTE increased during the study period. In addition, the risk of developing PTE was significantly associated with gender, EPTS, LOC time, SDH, brain contusion sites, surgery and TBI severity. However, further researches may be needed to predict the risk of PTE in combination with quantitative factors.

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

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.

Epidemiology of traumatic brain injury-associated epilepsy and early use of anti-epilepsy drugs: An analysis of insurance claims data, 2004–2014

BackgroundAbout 2.8 million TBI-related emergency department visits, hospitalizations and deaths occurred in 2013 in the United States. Post-traumatic epilepsy (PTE) can be a disabling, life-long outcome of TBI. ObjectivesThe purpose of this study is to address the probability of developing PTE within 9 years after TBI, the risk factors associated with PTE, the prevalence of anti-epileptic drug (AEDs) use, and the effectiveness of using AEDs prophylactically after TBI to prevent the development of PTE. MethodsUsing MarketScan® databases covering commercial, Medicare Supplemental, and multi-state Medicaid enrollees from 2004 to 2014, we examined the incidence of early seizures (within seven days after TBI) and cumulative incidence of PTE, the hazard ratios (HR) of PTE by age, gender, TBI severity, early seizure and AED use (carbamazepine, clonazepam, divalproex sodium, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, phenytoin, pregabalin, topiramate, acetazolamide). We used backward selection to build the final Cox proportional hazard model and conducted multivariable survival analysis to obtain estimates of crude and adjusted HR (cHRs, aHRs) of PTE and 95% confidence intervals (CI). ResultsThe incidence of early seizure among TBI patients in our study was 0.5%. The cumulative incidence of PTE increased from 1.0% in one year to 4.0% in nine years. Most patients with TBI (93%) were not prescribed any AED. Gender was not associated with PTE. The risk of PTE was higher for individuals with older age, early seizures, and more severe TBI. Only individuals using prophylactic acetazolamide had significantly lower risk of PTE (aHR = 0.6, CI 0.4-0.9) compared to those not using any AED. ConclusionThe probability of developing PTE increased within the study period. The risk of developing PTE significantly increased with age, early seizure and TBI severity. Most of the individuals did not receive AED after TBI. There was no evidence suggesting AEDs helped to prevent PTE with the possible exception of acetazolamide. However, further studies may be needed to test the efficacy of acetazolamide in preventing PTE.

Clinical and diagnostic profiles of post traumatic epilepsy patients

Background: One of the most common identifiable causes of epilepsy is traumatic brain injury (TBI). The incidence of post-traumatic epilepsy is between 5 and 50% according to numerous studies, and often has a progressive character.

Chapter 33 - Post-traumatic epilepsy: clinical clues to pathogenesis and paths to prevention

Post-traumatic epilepsy (PTE) remains one of the most intractable consequences of traumatic brain injury (TBI) and its incidence and characteristics have remained relatively constant through the past century, in spite of significant advances in medical management. Survivors of military penetrating head injury (PHI) suffer by far the highest incidence of (PTE), ranging from 32% to 55%, and they are a particularly valuable group in which to study this complication. Clues to the high incidence of PTE in PHI survivors are likely related to dural penetration with free intracerebral blood, and perhaps to retained ferric metal fragments. The failure of well-reasoned and well-conducted trials evaluating conventional anticonvulsants for prevention of PTE also offers important clues and has forced us to reconsider our approach to management. Here we briefly review the clinical characteristics of PHI patients with PTE, with an emphasis on clues to pathogenesis that can generalize to other types of head injury; followed by a discussion of the pathogenetic mechanisms common to epilepsy, PHI, and TBI in general, with an eye to future neuroprotection and PTE prophylaxis. Future studies that more directly target the basic pathogenesis of TBI, including neuroinflammation and lipid peroxidation with their consequent excitotoxic mechanisms and aberrant regeneration, may ultimately prove to be more fruitful in the struggle to understand and control this especially stubborn complication of head injury.

Epilepsy after head injury in dogs: A natural model of posttraumatic epilepsy

In humans, traumatic brain injury (TBI) is one of the most common causes of acquired (symptomatic) epilepsy, but as yet there is no treatment to prevent the development of epilepsy after TBI. Animal models of posttraumatic epilepsy (PTE) are important to characterize epileptogenic mechanisms of TBI and to identify clinically effective antiepileptogenic treatments. The prevalence and phenomenology of naturally occurring canine epilepsy are similar to those in human epilepsy. However, the risk of epilepsy after TBI has not been systemically studied in dogs. We therefore performed a large retrospective study in 1,000 dogs referred to our clinical department over a period of 11.5years with the aim to determine the incidence of early and late seizures after head trauma in this species. Two strategies were used: in group I (n=392), we evaluated whether dogs referred for the treatment of a head trauma (group Ia) or other trauma (group Ib) developed seizures after the trauma, whereas in group II (n=608) we evaluated whether dogs referred for the treatment of recurrent epileptic seizures had a history of head trauma. Data for this study were obtained from our clinical database, questionnaires sent to the dogs' owners, and owner interviews. In group Ia, 6.6% of the dogs developed PTE, which was significantly different from group Ib (1.9%), indicating that head trauma increased the risk of developing epilepsy by a factor of 3.4. The risk of PTE increased with severity of TBI; 14.3% of the dogs with skull fracture developed PTE. In group II, 15.5% of the dogs with epilepsy had a history of head injury, which was significantly higher than the incidence of PTE determined for group Ia. Our study indicates that head trauma in dogs is associated with a significant risk of developing epilepsy. Therefore, dogs with severe TBI are an interesting natural model of PTE that provides a novel translational platform for studies on human PTE.