Chronic traumatic encephalopathy research viewed in the public domain: What makes headlines?

Objective: To determine chronic traumatic encephalopathy (CTE)-related publication characteristics associated with higher Altmetric scores.Methods: A systematic review of the CTE literature was conducted using PubMed. Publications were coded for: journal impact factor (JIF); publication type (primary versus non-primary data collection); discussion of American football; contact sport-CTE association conclusion (yes versus no/neutral); and Altmetric score. Multivariable ordinal logistic regression identified predictors of higher Altmetric scores.Results: Most of the 270 CTE-related publications did not include primary data collection (60%). The median Altmetric score was 12 (range = 0-3745). Higher Altmetric scores were associated with primary data collection [Odds ratio (OR)Adjusted = 2.29; 95% confidence interval (CI) = 1.35-3.89] and discussing American football (ORAdjusted = 2.11; 95%CI = 1.24-3.59). Among publications concluding contact sport-CTE associations, higher Altmetric scores were associated with higher JIF (3-point-JIF-increase ORAdjusted = 2.11; 95%CI = 1.24-3.59); however, the association of higher Altmetric scores with higher JIF was not found among neutral publications or those concluding no contact sport-CTE associations (3-point-JIF-increase ORAdjusted = 1.07; 95%CI = 0.94-1.22).Conclusions: Most CTE-related publications (60%) did not involve primary data collection. Publication characteristics such as higher JIF and concluding contact sport-CTE associations were associated with higher Altmetric scores. It is important for the academic community to consider strategies to counter publication and promotion bias in the presentation of CTE literature.

Is contact sport participation associated with chronic traumatic encephalopathy or neurodegenerative decline? A systematic review and meta-analysis.

INTRODUCTION: We sought to evaluate a potential association between contact vs. non-contact sport participation and long-term neurologic outcomes and chronic traumatic encephalopathy (CTE). EVIDENCE ACQUISITION: PubMed/Embase/PsycINFO/CINAHL databases were queried for studies between 1950-2020 with contact and non-contact sports, longitudinal assessment >10 years, and long-term neurologic outcomes in four-domains: I) clinical diagnosis; II) CTE neuropathology; III) neurocognition; and IV) neuroimaging. EVIDENCE SYNTHESIS: Of 2561 studies, 37 met inclusion criteria, and 19 contained homogenous outcomes usable in the meta-analysis. Domain I: Across six studies, no significant relationship was seen between contact sport participation and antemortem diagnosis of neurodegenerative disease or death related to such a diagnosis (RR1.88, P=0.054, 95%CI0.99, 3.49); however, marginal significance (P<0.10) was obtained. Domain II: Across three autopsy studies, no significant relationship was seen between contact sport participation and CTE neuropathology (RR42.39, P=0.086, 95%CI0.59, 3057.46); however, marginal significance (P<0.10) was obtained. Domain III: Across five cognitive studies, no significant relationship was seen between contact sport participation and cognitive function on the Trail Making Test (TMT) scores A/B (A:d=0.17, P=0.275,95% CI-0.13, 0.47; B:d=0.13, P=0.310, 95%CI-0.12, 0.38). Domain IV: In 10 brain imaging-based studies, 32% comparisons showed significant differences between those with a history of contact sport vs. those without. CONCLUSIONS: No statistically significant increased risk of neurodegenerative diagnosis, CTE neuropathology, or neurocognitive changes was found to be associated with contact sport participation, yet marginal significance was obtained in two domains. A minority of imaging comparisons showed differences of uncertain clinical significance. These results highlight the need for longitudinal investigations using standardized contact sport participation and neurodegenerative criteria.

Attention-Deficit Hyperactivity Disorder and Learning Disabilities Modify Recovery and Sport Behavior Following Sport-Related Concussion.

Limited evidence exists concerning how a diagnosis of attention-deficit hyperactivity disorder and/or learning disabilities (ADHD/LD) modifies recovery and behavior following sport-related concussion (SRC). To understand how ADHD/LD modifies the post-SRC experience, we conducted a retrospective cohort study of concussed young athletes through phone interviews with patients and guardians. Outcomes included time until symptom resolution (SR) and return-to-learn (RTL), plus subjective changes in post-SRC activity and sports behavior. Multivariate Cox and logistic regression was performed, adjusting for biopsychosocial characteristics. The ADHD/LD diagnosis was independently associated with worse outcomes, including lower likelihood to achieve SR (hazard ratio [HR] = 0.62, 95% confidence interval [CI] = [0.41-0.94]; P = .02) and RTL (HR = 0.55, 95% CI = [0.36-0.83]; P < .01) at any time following injury, and increased odds of changing sport behavior after concussion (odds ratio [OR] = 3.26, 95% CI = [1.26-8.42], P = .02), often to a safer style of play (62.5% vs 39.6%; P = .02) or retiring from the sport (37.5% vs 18.5%; P = .02). These results provide further evidence of the unique needs for athletes with ADHD/LD following SRC.

Prevalence of the interthalamic adhesion in the human brain: a review of literature.

The interthalamic adhesion (IA) is a midline structure connecting the two thalami. Though it has been studied for centuries its exact function remains elusive. Early studies had noted its peculiar absence even among some healthy individuals. Population studies have investigated the differences in prevalence of IA in pathologic conditions and healthy controls. However, there is a general lack of consensus on IA prevalence in the healthy population. Understanding the true prevalence is critical in providing context for future studies, as well as uncovering further clues regarding IA's function. We systematically reviewed the existing literature to evaluate the prevalence of IA. The average prevalence among reviewed studies was higher than previously reported, at 87.3%. Studies utilizing magnetic resonance imaging rather than cadaveric specimens reported higher rates of IA prevalence. A higher prevalence among females was noted throughout the literature that persisted regardless of acquisition modality utilized.

Bone Cement Cranioplasty Reduces Cerebrospinal Fluid Leak Rate after Microvascular Decompression: A Single-Institutional Experience.

Background Microvascular decompression (MVD) is a common surgical treatment for cranial nerve compression, though cerebrospinal fluid (CSF) leak is a known complication of this procedure. Bone cement cranioplasty may reduce rates of CSF leak. Objective To compare rates of CSF leak before and after implementation of bone cement cranioplasty for the reconstruction of cranial defects after MVD. Methods Retrospective chart review was performed of patients who underwent MVD through retrosigmoid craniectomy for cranial nerve compression at a single institution from 1998 to 2017. Study variables included patient demographics, medical history, type of closure, and postoperative complications such as CSF leak, meningitis, lumbar drain placement, and ventriculoperitoneal shunt insertion. Cement and noncement closure groups were compared, and predictors of CSF leak were assessed using a multivariate logistic regression model. Results A total of 547 patients treated by 10 neurosurgeons were followed up for more than 20 years, of whom 288 (52.7%) received cement cranioplasty and 259 (47.3%) did not. Baseline comorbidities were not significantly different between groups. CSF leak rate was significantly lower in the cement group than in the noncement group (4.5 vs. 14.3%; p < 0.001). This was associated with significantly fewer patients developing postoperative meningitis (0.7 vs. 5.2%; p = 0.003). Multiple logistic regression model demonstrated noncement closure as the only independent predictor of CSF leak (odds ratio: 3.55; 95% CI: 1.78-7.06; p < 0.001). Conclusion CSF leak is a well-known complication after MVD. Bone cement cranioplasty significantly reduces the incidence of postoperative CSF leak and other complications. Modifiable risk factors such as body mass index were not associated with the development of CSF leak.

The value of simplicity: externally validating the Baylor cranial gunshot wound prognosis score.

OBJECTIVE: Gunshot wounds to the head (GSWH) are devastating injuries with a grim prognosis. Several prognostic scores have been created to estimate mortality and functional outcome, including the so-called Baylor score, an uncomplicated scoring method based on bullet trajectory, patient age, and neurological status on admission. This study aimed to validate the Baylor score within a temporally, institutionally, and geographically distinct patient population. METHODS: Data were obtained from the trauma registry at a level I trauma center in the southeastern US. Patients with a GSWH in which dural penetration occurred were identified from data collected between January 1, 2009, and June 30, 2019. Patient demographics, medical history, bullet trajectory, intent of GSWH (e.g., suicide), admission vital signs, Glasgow Coma Scale score, pupillary response, laboratory studies, and imaging reports were collected. The Baylor score was calculated directly by using its clinical components. The ability of the Baylor score to predict mortality and good functional outcome (Glasgow Outcome Scale score 4 or 5) was assessed using the receiver operating characteristic curve and the area under the curve (AUC) as a measure of performance. RESULTS: A total of 297 patients met inclusion criteria (mean age 38.0 [SD 15.7] years, 73.4% White, 85.2% male). A total of 205 (69.0%) patients died, whereas 69 (23.2%) patients had good functional outcome. Overall, the Baylor score showed excellent discrimination of mortality (AUC = 0.88) and good functional outcome (AUC = 0.90). Baylor scores of 3-5 underestimated mortality. Baylor scores of 0, 1, and 2 underestimated good functional outcome. CONCLUSIONS: The Baylor score is an accurate and easy-to-use prognostic scoring tool that demonstrated relatively stable performance in a distinct cohort between 2009 and 2019. In the current era of trauma management, providers may continue to use the score at the point of admission to guide family counseling and to direct investment of healthcare resources.

Incorporating conditional survival into prognostication for gunshot wounds to the head.

OBJECTIVE: Several scores estimate the prognosis for gunshot wounds to the head (GSWH) at the point of hospital admission. However, prognosis may change over the course of the hospital stay. This study measures the accuracy of the Baylor score among patients who have already survived the acute phase of hospitalization and generates conditional outcome curves for the duration of hospital stay for patients with GSWH. METHODS: Patients in whom GSWH with dural penetration occurred between January 2009 and June 2019 were identified from a trauma registry at a level I trauma center in the southeastern US. The Baylor score was calculated using component variables. Conditional overall survival and good functional outcome (Glasgow Outcome Scale score of 4 or 5) curves were generated. The accuracy of the Baylor score in predicting mortality and functional outcome among acute-phase survivors (survival > 48 hours) was assessed using receiver operating characteristic curves and the area under the curve (AUC). RESULTS: A total of 297 patients were included (mean age 38.0 [SD 15.7] years, 73.4% White, 85.2% male), and 129 patients survived the initial 48 hours of admission. These acute-phase survivors had a decreased mortality rate of 32.6% (n = 42) compared to 68.4% (n = 203) for all patients, and an increased rate of good functional outcome (48.1%; n = 62) compared to the rate for all patients (23.2%; n = 69). Among acute-phase survivors, the Baylor score accurately predicted mortality (AUC = 0.807) and functional outcome (AUC = 0.837). However, the Baylor score generally overestimated true mortality rates and underestimated good functional outcome. Additionally, hospital day 18 represented an inflection point of decreasing probability of good functional outcome. CONCLUSIONS: During admission for GSWH, surviving beyond the acute phase of 48 hours doubles the rates of survival and good functional outcome. The Baylor score maintains reasonable accuracy in predicting these outcomes for acute-phase survivors, but generally overestimates mortality and underestimates good functional outcome. Future prognostic models should incorporate conditional survival to improve the accuracy of prognostication after the acute phase.

Traumatic Cerebrovascular Injuries Associated with Gunshot Wounds to the Head: A Single-Institution Ten-Year Experience.

BACKGROUND: Cerebrovascular injury (CVI) is a potentially devastating complication of gunshot wounds to the head (GSWH), with yet unclear incidence and prognostic implications. Few studies have also attempted to define CVI risk factors and their role in patient outcomes. We aimed to describe 10 years of CVI from GSWH and characterize these injury patterns. METHODS: Single-institution data from 2009 to 2019 were queried to identify patients presenting with dural-penetrating GSWH. Patient records were reviewed for GSWH characteristics, CVI patterns, management, and follow-up. RESULTS: Overall, 63 of 297 patients with GSWH underwent computed tomography angiography (CTA) with 44.4% showing CVI. The middle cerebral artery (22.2%), dural venous sinuses (15.9%), and internal carotid artery (14.3%) were most frequently injured. Arterial occlusion was the most prominent injury type (22.2%) followed by sinus thrombosis (15.9%). One fifth of patients underwent delayed repeat CTA, with 20.1% showing new/previously unrecognized CVI. Bihemispheric bullet tracts were associated with CVI occurrence (P = 0.001) and mortality (P = 0.034). Dissection injuries (P = 0.013), injuries to the vertebrobasilar system (P = 0.036), or the presence of ≥2 concurrent CVIs (P = 0.024) were associated with increased risk of mortality. Of patients with CVI on initial CTA, 30% died within the first 24 hours. CONCLUSIONS: CVI was found in 44.4% of patients who underwent CTA. Dissection and vertebrobasilar injuries are associated with the highest mortality. CTA should be considered in any potentially survivable GSWH. Longitudinal study with consistent CTA use is necessary to determine the true prevalence of CVI and optimize the use of imaging modalities.