Microstructure of the Corpus Callosum Long after Pediatric Concussion

Effects of Cumulative Head Impact Exposure in Adolescent Male Contact and Collision Sport Student Athletes

OBJECTIVE

This prospective cohort study aimed to investigate the association between head impact exposure (HIE) and neuropsychological sequelae in high school football and ice hockey players over 1 year.

SETTING

Community sample.

PARTICIPANTS

A cohort of 52 adolescent American football and ice hockey players were enrolled in the study, with a final study sample of 35 included in analyses.

DESIGN

The study followed a prospective cohort design, with participants undergoing neuropsychological screening and accelerometer-based measurement of HIE over 1 season.

MAIN MEASURES

Changes in cognition, emotions, behavior, and reported symptoms were assessed using standardized neuropsychological tests and self-reported questionnaires.

RESULTS

Cumulative HIE was not consistently associated with changes in cognition, emotions, behavior, or reported symptoms. However, it was linked to an isolated measure of processing speed, showing inconsistent results based on the type of HIE. History of previous concussion was associated with worsened verbal memory recognition (ImPACT Verbal Memory) but not on a more robust measure of verbal memory (California Verbal Learning Test [CVLT]). Reported attention-deficit/hyperactivity disorder history predicted improved neurocognitive change scores. No associations were found between reported history of anxiety/depression or headaches/migraines and neuropsychological change scores.

CONCLUSION

Overall, our findings do not support the hypothesis that greater HIE is associated with an increase in neuropsychological sequelae over time in adolescent football and ice hockey players. The results align with the existing literature, indicating that HIE over 1 season of youth sports is not consistently associated with significant neuropsychological changes. However, the study is limited by a small sample size, attrition over time, and the absence of performance validity testing for neurocognitive measures. Future studies with larger and more diverse samples, longer follow-up, and integration of advanced imaging and biomarkers are needed to comprehensively understand the relationship between HIE and neurobehavioral outcomes. Findings can inform guidelines for safe youth participation in contact sports while promoting the associated health and psychosocial benefits.

Interhemispheric transfer time and concussion in adolescents: A longitudinal study using response time and event-related potential measures

Introduction

Concussion in children and adolescents is a public health concern with higher concussion incidence than adults and increased susceptibility to axonal injury. The corpus callosum is a vulnerable location of concussion-related white matter damage that can be associated with short- and long-term effects of concussion. Interhemispheric transfer time (IHTT) of visual information across the corpus callosum can be used as a direct measure of corpus callosum functioning that may be impacted by adolescent concussion with slower IHTT relative to matched controls. Longitudinal studies and studies testing physiological measures of IHTT following concussion in adolescents are lacking.

Methods

We used the N1 and P1 components of the scalp-recorded brain event-related potential (ERP) to measure IHTT in 20 adolescents (ages 12–19 years old) with confirmed concussion and 16 neurologically-healthy control participants within 3 weeks of concussion (subacute stage) and approximately 10 months after injury (longitudinal).

Results

Separate two-group (concussion, control) by two-time (3 weeks, 10 months) repeated measures ANOVAs on difference response times and IHTT latencies of the P1 and N1 components showed no significant differences by group (ps ≥ 0.25) nor by time (ps ≥ 0.64), with no significant interactions (ps ≥ 0.15).

Discussion

Results from the current sample suggest that measures of IHTT may not be strongly influenced at 3 weeks or longitudinally following adolescent concussion using the current IHTT paradigm.

A Scoping Review of Magnetic Resonance Modalities Used in Detection of Persistent Postconcussion Symptoms in Pediatric Populations

Up to 30% of youth with concussion experience PPCSs (PPCS) lasting 4 weeks or longer, and can significantly impact quality of life. Magnetic resonance imaging (MRI) has the potential to increase understanding of causal mechanisms underlying PPCS. However, there are no clear modalities to assist in detecting PPCS. This scoping review aims to synthesize findings on utilization of MRI among children and youth with PPCS, and summarize progress and limitations. Thirty-six studies were included from 4907 identified papers. Many studies used multiple modalities, including (1) structural (n = 27) such as T1-weighted imaging, diffusion weighted imaging, and susceptibility weighted imaging; and (2) functional (n = 23) such as functional MRI and perfusion-weighted imaging. Findings were heterogeneous among modalities and regions of interest, which warrants future reviews that report on the patterns and potential advancements in the field. Consideration of modalities that target PPCS prediction and sensitive modalities that can supplement a biopsychosocial approach to PPCS would benefit future research.

Susceptibility-Weighted Magnetic Resonance Imaging (MRI) of Microbleeds in Pediatric Concussion

OBJECTIVE

The long-term consequences of pediatric concussion on brain structure are poorly understood. This study aimed to evaluate the presence and clinical significance of cerebral microbleeds several years after pediatric concussion.

METHODS

Children and adolescents 8-19 years of age with either a history of concussion (n = 35), or orthopedic injury (n = 20) participated. Mean time since injury for the sample was 30.4 months (SD = 19.6). Participants underwent susceptibility-weighted imaging, rated their depression and postconcussion symptoms, and completed cognitive testing. Parents of participants also completed symptom ratings for their child. Hypointensities in susceptibility-weighted images indicative of cerebral microbleeds were calculated as a measure of hypointensity burden.

RESULTS

Hypointensity burden did not differ significantly between participants with a history of concussion and those with a history of orthopedic injury. Depression ratings (self and parent report), postconcussion symptom ratings (self and parent report), and cognitive performance did not significantly correlate with hypointensity burden in the concussion group.

CONCLUSIONS

These findings suggest that at approximately 2.5 years postinjury, children and adolescents with prior concussion do not have a greater amount of cerebral microbleeds compared to those with orthopedic injury. Future research should use longitudinal study designs and investigate children with persistent postconcussive symptoms to gain better insight into the long-term effects of concussion on cerebral microbleeds.

Implications of DTI in mild traumatic brain injury for detecting neurological recovery and predicting long-term behavioural outcome in paediatric and young population-a systematic review

PURPOSE

This systematic review was done with the aim to answer these three questions: 1) Is there any change in diffusion metrics in MRI-DTI sequences after mild traumatic brain injury in paediatric and young population?, 2) Is there any correlation of these changes in diffusion metrics with severity of post concussion symptoms?, 3) Is the change in diffusion metrics predictive of neurocognitive function or neurological recovery?

MATERIAL AND METHODS

Eligibility criteria- Mild TBI patients upto 22 years of age, MRI- DTI sequence done post injury, Outcome measurement with follow up at least for onemonth and articles published in English language only. Data sources- PubMed, EMBASE, CINAHL, Scopus and Cochrane RESULTS: Some studies show increased FA and some studies show decrease FA and few showed no change in white matter microstructure in mTBI patients and this depends on the duration of injury. Prediction of PCSs severity on the basis of changes in white matter microstructure showed inconsistent results. Radiological recovery in contrast to clinical recovery, is often delayed ranging from 6 months to 2-3 years. But change in diffusion metrics after mTBI is not definite predictive of neurocognitive outcomes.

CONCLUSION

Large, properly designed, multicentric studies with appropriate extracranial or orthopedic control and long follow up are needed to establish the use of DTIin mTBI for predicting behavioral outcome.

Cortical Volume and Thickness in Youth Several Years After Concussion

OBJECTIVE

The long-term effects of pediatric concussion on brain morphometry remain poorly delineated. This study used magnetic resonance imaging (MRI) to investigate cortical volume and thickness in youth several years after concussion.

METHODS

Participants aged 8-19 years old with a history of concussion (n = 37) or orthopedic injury (n = 20) underwent MRI, rated their postconcussion symptoms, and completed cognitive testing on average 2.6 years (SD = 1.6) after injury. FreeSurfer was used to obtain cortical volume and thickness measurements as well as determine any significant correlations between brain morphometry, postconcussion symptoms (parent and self-report), and cognitive functioning.

RESULTS

No significant group differences were found for either cortical volume or thickness. Youth with a history of concussion had higher postconcussion symptom scores (both parent and self-report Postconcussion Symptom Inventory) than the orthopedic injury group, but symptom ratings did not significantly correlate with cortical volume or thickness. Across both groups, faster reaction time on a computerized neurocognitive test battery (CNS Vital Signs) was associated with a thinner cortex in the left pars triangularis of the inferior frontal gyrus and the left caudal anterior cingulate. Better verbal memory was associated with a thinner cortex in the left rostral middle frontal gyrus.

CONCLUSION

Findings do not support differences in cortical volume or thickness approximately 2.5 years postconcussion in youth, suggesting either long-term cortical recovery or no cortical differences as a result of injury. Further research using a longitudinal study design and larger samples is needed.