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.

Chronic traumatic encephalopathy (CTE) is associated with pathological changes, yet detecting these changes during life has proven elusive. Positron emission tomography (PET) offers the potential for identifying such pathology. Few studies have been completed to date and their approaches and results have been diverse. It was the objective of this review to systematically examine relevant research using ligands for PET that bind to identified pathology in CTE. We focused on identification of patterns of binding and addressing gaps in knowledge of PET imaging for CTE. A comprehensive literature search was conducted. Data used were published on or before May 22, 2017. As the extant literature is limited, any peer-reviewed article assessing military, contact sports athletes, or professional fighters was considered for inclusion. The main outcomes were regional binding to brain regions identified through control comparisons or through clinical metrics (e.g., standardized uptake volume ratios). A total of 1207 papers were identified for review, of which six met inclusion criteria. Meta-analyses were planned but were deemed inappropriate given the small number of studies identified. Methodological concerns in these initial papers included small sample sizes, lack of a control comparison, use of nonstandard statistical procedures to quantify data, and interpretation of potentially off-target binding areas. Across studies, the hippocampi, amygdalae, and midbrain had reasonably consistent increased uptake. Evidence for increased uptake in cortical regions was less consistent. The evidence suggests that the field of PET imaging in those at risk for CTE remains nascent. As the field evolves to include more stringent studies, ligands for PET may prove an important tool in identifying CTE in vivo.

The objective of this systematic review and meta-analysis is to evaluate whether the pre-injury use of antiplatelet therapy (APT) is associated with increased risk of traumatic intracranial hemorrhage (tICH) on CT scan. PubMed, Medline, Embase, Cochrane Central, reference lists, and national guidelines on traumatic brain injury were used as data sources. Eligible studies were cohort studies and case-control studies that assessed the relationship between APT and tICH. Studies without control group were not included. The primary outcome of interest was tICH on CT. Two reviewers independently selected studies, assessed methodological quality, and extracted outcome data. This search resulted in 10 eligible studies with 20,247 patients with head injury that were included in the meta-analysis. The use of APT in patients with head injury was associated with significant increased risk of tICH compared with control (odds ratio [OR] 1.87, 95% confidence interval [CI]1.27-2.74). There was significant heterogeneity in the studies (I2 84%), although almost all showed an association between APT use and tICH. This association could not be established for patients receiving aspirin monotherapy. When considering only patients with mild traumatic brain injury (mTBI), the OR is 2.72 (95% CI 1.92-3.85). The results were robust to sensitivity analysis on study quality. In summary, APT in patients with head injury is associated with increased risk of tICH; this association is most relevant in patients with mTBI. Whether this association is the result of a causal relationship and whether this relationship also exists for patients receiving aspirin monotherapy cannot be established with the current review and meta-analysis.