Clinical features and early detection of sport-related concussion

Changes in the central nervous system in football players: an MRI study

BACKGROUND

Football (soccer) is the world's most popular team sport.

PURPOSE

To comprehensively examine the brain in football (soccer) players, with the use of magnetic resonance imaging (MRI) techniques.

MATERIAL AND METHODS

The study involved 65 football players and 62 controls. The MR examinations were performed using MR 1.5-T system (Optima MR 360; GE Medical Systems). The examinations were carried out in the 3D Bravo, CUBE, FSEpropeller, and diffusion-weighted imaging (DWI) sequences. The 1HMRS signal was obtained from the volume of interest in the frontal and occipital lobes on both sides.

RESULTS

The present study, based on structural MRI, shows some changes in the brains of the group of football players. The findings show asymmetry of the ventricular system in four football players, arachnoid cysts in the parieto-occipital region, and pineal cysts. NAA/Cr concentration in the right frontal lobe was lower in the football players than in the controls, and the Glx/Cr concentration in the right occipital lobe was higher. The apparent diffusion coefficient value is lower in football players in the occipital lobes.

CONCLUSION

Playing football can cause measurable changes in the brain, known to occur in patients diagnosed with traumatic brain injury. The present findings fill the gap in the literature by contributing evidence showing that playing football may lead to changes in the brain, without clinical symptoms of concussion.

Sport level and sex differences in sport-related concussion among Japanese collegiate athletes: Epidemiology, knowledge, reporting behaviors, and reported symptoms

This study investigated the incidence of sport-related concussion (SRC) in sports, effect of athlete knowledge on reporting behavior differences between collegiate and non-collegiate athletes, and differences in SRC symptoms between sexes and level of participation. In this cross-sectional survey, 1 344 Japanese collegiate and non-collegiate athletes from a single institute were analyzed. Using a web-based survey, demographics, general SRC, knowledge of SRC, the most recent SRC reporting behaviors, and symptom presentation were examined. The prevalence of SRC during the academic year 2016-2017 was 2.68 (95% confidence interval [CI]: 1.88-3.69) across all sports. The prevalence of SRC was 33.3 (95% CI: 17.96-51.83) in rugby union and 8.33 (95% CI: 1.03-27.00) in women's soccer. The prevalence of SRC in males (3.47 [95% CI: 2.38-4.86] was 3.65 times higher than that in females (0.95 [95% CI: 0.26-2.41]). In total, the mean total score of knowledge was 5.30 (4.2) across 25 questions; dizziness was the most well-known symptom (867/1 344, 64.5%), followed by headache (59.3%). Being more emotional (44/1 345, 3.3%) was the least frequently known symptom. Level of participation did not affect scores (5.16 [3.96] vs. 5.52 [4.54]; p ​= ​0.131). All 87 disclosing participants experienced drowsiness and irritability and felt more emotional. In terms of sex and participant level, no significant differences were found in any symptoms. This study found very low rates of concussion education in Japan. Dissemination of concussion education is essential in the future to recognize concussion earlier and prevent severe concussive injury.

Numerical Simulation of Concussive-Generated Cortical Spreading Depolarization to Optimize DC-EEG Electrode Spacing for Noninvasive Visual Detection

BACKGROUND

Cortical spreading depolarization (SD) is a propagating depolarization wave of neurons and glial cells in the cerebral gray matter. SD occurs in all forms of severe acute brain injury, as documented by using invasive detection methods. Based on many experimental studies of mechanical brain deformation and concussion, the occurrence of SDs in human concussion has often been hypothesized. However, this hypothesis cannot be confirmed in humans, as SDs can only be detected with invasive detection methods that would require either a craniotomy or a burr hole to be performed on athletes. Typical electroencephalography electrodes, placed on the scalp, can help detect the possible presence of SD but have not been able to accurately and reliably identify SDs.

METHODS

To explore the possibility of a noninvasive method to resolve this hurdle, we developed a finite element numerical model that simulates scalp voltage changes that are induced by a brain surface SD. We then compared our simulation results with retrospectively evaluated data in patients with aneurysmal subarachnoid hemorrhage from Drenckhahn et al. (Brain 135:853, 2012).

RESULTS

The ratio of peak scalp to simulated peak cortical voltage, Vscalp/Vcortex, was 0.0735, whereas the ratio from the retrospectively evaluated data was 0.0316 (0.0221, 0.0527) (median [1st quartile, 3rd quartile], n = 161, p < 0.001, one sample Wilcoxon signed-rank test). These differing values provide validation because their differences can be attributed to differences in shape between concussive SDs and aneurysmal subarachnoid hemorrhage SDs, as well as the inherent limitations in human study voltage measurements. This simulated scalp surface potential was used to design a virtual scalp detection array. Error analysis and visual reconstruction showed that 1 cm is the optimal electrode spacing to visually identify the propagating scalp voltage from a cortical SD. Electrode spacings of 2 cm and above produce distorted images and high errors in the reconstructed image.

CONCLUSIONS

Our analysis suggests that concussive (and other) SDs can be detected from the scalp, which could confirm SD occurrence in human concussion, provide concussion diagnosis on the basis of an underlying physiological mechanism, and lead to noninvasive SD detection in the setting of severe acute brain injury.

Concussion Office Based Rehabilitation Assessment: A Novel Clinical Tool for Concussion Assessment and Management

The Concussion Office Based Rehabilitation Assessment (COBRA) is a novel tool constructed to ensure a comprehensive assessment of patients who may have sustained a concussion. The SCAT-5 (Sport Concussion Assessment Tool) has long been the gold standard for concussion assessment, however, it was designed as a sideline tool and its utility can be seen to decrease after a few days post-concussion. It also does not prompt evaluation of all the phenotypes of concussion. As such, the COBRA was created to assess the majority of potential manifestations of concussion in the office setting a day or two after an injury has been sustained. The COBRA utilizes the eight phenotypes of concussion as a guide to assess each of the potential biopsychosocial features that can be associated with these injuries and can be used to guide evidence-based treatments. Through early identification of concussion phenotypes, the clinician may start optimal treatment and hopefully prevent prolonged recovery and persisting symptoms.