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The Q-Collar designed to facilitate the actions of the compressive effect of the omohyoids to reduce blood outflow of the brain (A) and produce a tighter fit of the brain within the cranium (B).
Source publication
Objectives
Utilize a prospective in vivo clinical trial to evaluate the potential for mild neck compression applied during head impact exposure to reduce anatomical and physiological biomarkers of brain injury.
Methods
This project utilized a prospective randomized controlled trial to evaluate effects of mild jugular vein (neck) compression (colla...
Citations
... Four out of 11 studies found increased mean diffusivity (MD) values [60,61,63,64]. One study reported increased FA values (which was only identified in one of the two observed teams) [62]. ...
... Lastly, radial diffusivity (RD) decrease was identified in three articles [58,65,66]. A subset of two articles highlighted increased RD values over time in the corpus callosum and the brainstem [61,64]. A total of seven out of 11 included studies in this section reported a significant relationship between cumulative head impact metrics (i. ...
... The current work shows that exposure to RSHIs exceeding a threshold of 10 g leads to white matter alterations in the athletes' brains [46,58,[60][61][62][63][64][65][66]. Specifically, the structural changes seem to be related to the total number of subconcussive head impacts > 10 g [46,51,60,63,65,66]. White matter alterations are mainly characterized by reduced fractional anisotropy (FA) values [46,[60][61][62]. ...
Repetitive subconcussive head impacts occur regularly in sports. However, the exact relationship between the biomechanical properties of repetitive subconcussive head impacts in sports and their consequences on brain structure and function has not been clarified yet. We therefore reviewed prospective cohort studies that objectively reported the biomechanical characteristics of repetitive subconcussive head impacts and their impact on brain anatomy and function. Only studies with a pre- to post measurement design were included. Twenty-four studies met the inclusion criteria. Structural white matter alterations, such as reduced fractional anisotropy and an increase in mean diffusivity values, seem to be evident in athletes exposed to repetitive subconcussive head impacts exceeding 10 g. Such changes are observable after only one season of play. Furthermore, it exists a dose-response relationship between white matter abnormalities and the total number of subconcussive head impacts. However, functional changes after repetitive subconcussive head impacts remain inconclusive. We therefore conclude that repetitive subconcussive head impacts induce structural changes, but thus far without overt functional changes.
... The most frequently observed changes are related to white matter microstructure which can occur in as short a time span as a single season and persist after the season ends (20)(21)(22)(23)(24). Common findings include reduced fractional anisotropy in long association tracts as well as increased mean and radial diffusivity in the corpus callosum (20)(21)(22)(23)(24), which collectively indicate reduced microstructural integrity resulting in less organized diffusion. Notably, findings of this nature are not homogeneous, with some research indicating no or very limited change in white matter integrity indicators (25)(26)(27). Given the frequency of RHSIs and the potential for long-term detrimental effect on brain structure, interventions that mitigate the adverse effects of RSHIs could significantly change the course of neurological damage. ...
Context
Repetitive sub-concussive head impacts (RSHIs) are common in American football and result in changes to the microstructural integrity of white matter. Both docosahexaenoic acid (DHA) and eicosapentaoic acid (EPA) supplementation exerted neuroprotective effects against RSHIs in animal models and in a prior study in football players supplemented with DHA alone.
Objective
Here, we present exploratory neuroimaging outcomes from a randomized controlled trial of DHA + EPA supplementation in American football players. We hypothesized that supplementation would result in less white matter integrity loss on diffusion weighted imaging over the season.
Design, setting, participants
We conducted a double-blind placebo-controlled trial in 38 American football players between June 2019 and January 2020.
Intervention
Participants were randomized to the treatment (2.442 g/day DHA and 1.020 g/day EPA) or placebo group for five times-per-week supplementation for 7 months. Of these, 27 participants were included in the neuroimaging data analysis (n = 16 placebo; n = 11 DHA + EPA).
Exploratory outcome measures
Changes in white matter integrity were quantified using both voxelwise diffusion kurtosis scalars and deterministic tractography at baseline and end of season. Additional neuroimaging outcomes included changes in regional gray matter volume as well as intra-regional, edge-wise, and network level functional connectivity. Serum neurofilament light (NfL) provided a peripheral biomarker of axonal damage.
Results
No voxel-wise between-group differences were identified on diffusion tensor metrics. Deterministic tractography using quantitative anisotropy (QA) revealed increased structural connectivity in ascending corticostriatal fibers and decreased connectivity in long association and commissural fibers in the DHA+EPA group compared to the placebo group. Serum NfL increases were correlated with increased mean (ρ = 0.47), axial (ρ = 0.44), and radial (ρ = 0.51) diffusivity and decreased QA (ρ = −0.52) in the corpus callosum and bilateral corona radiata irrespective of treatment group. DHA + EPA supplementation did preserve default mode/frontoparietal control network connectivity (g = 0.96, p = 0.024).
Conclusions
These exploratory findings did not provide strong evidence that DHA + EPA prevented or protected against axonal damage as quantified via neuroimaging. Neuroprotective effects on functional connectivity were observed despite white matter damage. Further studies with larger samples are needed to fully establish the relationship between omega-3 supplementation, RSHIs, and neuroimaging biomarkers.
Trial registration
ClinicalTrials.gov-NCT04796207
... Studies in a mouse model demonstrated that IJV compression leads to dramatic reductions of traumatic brain injury (TBI) from direct head trauma. 1 2 Subsequent studies have confirmed brain protective effects of IJV compression in the accumulated trauma of contact sports. [3][4][5][6][7][8][9][10] A critical gap in verifying the sequence of events between the IJV compression and slosh mitigation is the demonstration of filling the intracranial compartment and thereby reduction of the intracranial compliance. In upright humans, IJV compression must cause blood to back up against gravity, into the intracranial space, specifically the venous capacitance vessels and dural sinuses. ...
Background
Mild internal jugular vein (IJV) compression, aimed at increasing intracranial fluid volume to prevent motion of the brain relative to the skull, has reduced brain injury markers in athletes suffering repeated traumatic brain injuries. However, an increase in intracranial volume with IJV compression has not been well demonstrated. This study used transorbital ultrasound to identify changes in optic nerve sheath diameter (ONSD) as a direct marker of accompanying changes in intracranial volume.
Methods
Nineteen young, healthy adult volunteers (13 males and 6 females) underwent IJV compression of 20 cm H 2 O low in the neck, while in upright posture. IJV cross-sectional area at the level of the cricoid cartilage, and the change in right ONSD 3 mm behind the papillary segment of the optic nerve, were measured by ultrasound. Statistical analysis was performed using a paired t-test with Bonferroni correction.
Results
Mean (SD) cross-sectional area for the right IJV before and after IJV compression was 0.10 (0.05) cm ² and 0.57 (0.37) cm ² , respectively (p=0.001). ONSD before and after IJV compression was 4.6 (0.5) mm and 4.9 (0.5) mm, respectively (p=0.001).
Conclusions
These data verify increased cerebral volume following IJV compression, supporting the potential for reduced brain ‘slosh’ as a mechanism connecting IJV compression to possibly reducing traumatic brain injury following head trauma.
... This suggests a direct relationship between WM-based structural connectivity and EEG measures of cognitive responses. Myer et al. (2016) evaluated the so-called Q-Collar, a neck collar worn by athletes with the intention to protect the brain from head impacts. Aim of this study was to test the collar's effect on reducing neuroanatomical and neurophysiological damage in two groups of hockey players that either wore the collar or did not (the latter served as controls). ...
Implications of structural connections within and between brain regions for their functional counterpart are timely points of discussion. White matter microstructural organization and functional activity can be assessed in unison. At first glance, however, the corresponding findings appear variable, both in the healthy brain and in numerous neuro-pathologies. To identify consistent associations between structural and functional connectivity and possible impacts for the clinic, we reviewed the literature of combined recordings of electro-encephalography (EEG) and diffusion-based magnetic resonance imaging (MRI). It appears that the strength of event-related EEG activity increases with increased integrity of structural connectivity, while latency drops. This agrees with a simple mechanistic perspective: the nature of microstructural white matter influences the transfer of activity. The EEG, however, is often assessed for its spectral content. Spectral power shows associations with structural connectivity that can be negative or positive often dependent on the frequencies under study. Functional connectivity shows even more variations, which are difficult to rank. This might be caused by the diversity of paradigms being investigated, from sleep and resting state to cognitive and motor tasks, from healthy participants to patients. More challenging, though, is the potential dependency of findings on the kind of analysis applied. While this does not diminish the principal capacity of EEG and diffusion-based MRI co-registration, it highlights the urgency to standardize especially EEG analysis.
... TBSS) tool uses observer-independent voxelwise statistical analysis to process the complex information contained within diffusion-weighted images. [4][5][6][7][8][9][10][11][12][13][14][15][16] TBSS can be used to identify specific WM tracts and structures in the infant brain that correlate with later developmental outcomes. 8,10,[13][14][15] Previous studies have used TBSS to objectively assess WM microstructure following clinical events such as infection, sports injury, or preterm brain injury (eg, intraventricular hemorrhage) and to relate the associated WM alterations to outcomes. ...
... 8,10,[13][14][15] Previous studies have used TBSS to objectively assess WM microstructure following clinical events such as infection, sports injury, or preterm brain injury (eg, intraventricular hemorrhage) and to relate the associated WM alterations to outcomes. 9,11,[16][17][18][19] In addition, studies have used TBSS to identify brain regions and tracts in which FA significantly correlates with cognitive and motor outcomes at 2 years of age or younger. 10,13,15 These studies have consistently concluded that higher FA is associated with better motor, cognitive, and language functioning. ...
... As previously described, 27 all MR imaging scans were read by pediatric neuroradiologists qualitatively for the degree of brain injury/maturation and objective quantitative biometric measurements, using a standardized scoring system per Kidokoro et al. 28 This approached yielded a global brain abnormality score, which was categorized as normal (total score, 0-3), mild (total score, 4-7), moderate (total score, [8][9][10][11], or severe abnormality (total score, ≥12). All readings were unblinded to clinical history but blinded to outcomes. ...
Background and purpose:
Microstructural white matter abnormalities on DTI using Tract-Based Spatial Statistics at term-equivalent age are associated with cognitive and motor outcomes at 2 years of age or younger. However, neurodevelopmental tests administered at such early time points are insufficiently predictive of mild-moderate motor and cognitive impairment at school age. Our objective was to evaluate the microstructural antecedents of cognitive and motor outcomes at 3 years' corrected age in a cohort of very preterm infants.
Materials and methods:
We prospectively recruited 101 very preterm infants (<32 weeks' gestational age) and performed DTI at term-equivalent age. The Differential Ability Scales, 2nd ed, Verbal and Nonverbal subtests, and the Bayley Scales of Infant and Toddler Development, 3rd ed, Motor subtest, were administered at 3 years of age. We correlated DTI metrics from Tract-Based Spatial Statistics with the Bayley Scales of Infant and Toddler Development, 3rd ed, and the Differential Ability Scales, 2nd ed, scores with correction for multiple comparisons.
Results:
Of the 101 subjects, 84 had high-quality DTI data, and of these, 69 returned for developmental testing (82%). Their mean (SD) gestational age was 28.4 (2.5) weeks, and birth weight was 1121.4 (394.1) g. DTI metrics were significantly associated with Nonverbal Ability in the corpus callosum, posterior thalamic radiations, fornix, and inferior longitudinal fasciculus and with Motor scores in the corpus callosum, internal and external capsules, posterior thalamic radiations, superior and inferior longitudinal fasciculi, cerebral peduncles, and corticospinal tracts.
Conclusions:
We identified widespread microstructural white matter abnormalities in very preterm infants at term that were significantly associated with cognitive and motor development at 3 years' corrected age.
... 6 Research suggests that MJC facilitates the minimization of WMAs by slowing and reducing the impact of the brain against the skull (slosh mitigation) during sport activities; therefore, minimizing risk of concussions. [2][3][4] Athletes, especially football players, experience many blows over lower intensity that could cause the degree of brain slosh associated with these WMAs. Strategies for effective slosh mitigation then would be of considerable benefit for these populations. ...
... The mean age for the studied samples ranged from 16.3 to 17.3 years. [2][3][4] At the time of data collection, only the Neuroshield brand MJC device was available for purchase in Canada. At time of publication, the Q-Collar (Westport, CT, USA) has also been approved for sale in Canada. ...
Clinical question: Do mild jugular compression (MJC) devices reduce white matter alterations in high school-aged males playing collision sports? Clinical bottom line: There is moderate evidence at Strength of Recommendation B to support that MJC reduces WMAs in high school-aged males playing collision sports.
Accepted author manuscript version reprinted, by permission, from [International Journal of Athletic Therapy and Training, 2021, Published Ahead of Print, https://doi.org/10.1123/ijatt2020-0035. © Human Kinetics, Inc
... Woodpeckers are, however, rarely mentioned in scientific publications from 2016. These are publications which have sought to demonstrate the utility of the collar for reducing neurotrauma, not only in rats and pigs, but in humans acting in settings ranging from military drills (Bonnette et al., 2018;Yuan et al., 2019); to American football (Myer et al., 2016;Yuan et al., 2018aYuan et al., , 2017; to soccer (Myer et al., 2019;Yuan et al., 2018b). Nelson suggests that, once work is complete, the 'scaffold is dismantled' (Nelson, 2013, p. 7) and evidence of its presence disappears: the reduced visibility of the woodpecker within scientific publications can certainly be read in such terms. ...
Chronic Traumatic Encephalopathy, or CTE, is a neurodegenerative disease caused by traumatic brain injury and most frequently associated with contact sports such as American Football. Perhaps surprisingly, the woodpecker – an animal apparently immune to the effects of head impacts – has increasingly figured into debates surrounding CTE. On the one hand, the woodpecker is described as being contra-human and used to underscore the radical inappropriateness of humans playing football. On the other, there have been attempts to mitigate against the risk of CTE through the creation of biomimetic technologies inspired by woodpeckers. In this article I examine the highly politicized encounters between humans and woodpeckers and discuss how the politics of re-/dis-/en-tanglement during these interspecies relations is rendered meaningful. I show here, first, that those who seek to keep the human and the woodpecker apart envisage social overhaul while biomimetic technologies are put to work for the status quo. Second, I stress that different forms of entanglement have diverse sociopolitical consequences. I conclude by suggesting that the case of the woodpecker troubles a strand of contemporary scholarship in Science and Technology Studies that argues that biotechnologies are inherently transformatory and that foregrounding entanglement and interspecies relations is ethically generative. Instead, a discursive separation of nature and culture may be innovative.
... This aforementioned acceleration then may cause the brain to impact the side of the skull opposite to the injury [8,15,18]. Together, these injuries are known as, 'coup contrecoup injury' [17], and the mechanism of injury through which dynamic forces cause movement of the brain and its fluids within the skull is known as 'slosh' [6,15,19]. As most conventional protective methods, such as helmets, protect the skull but fail to mitigate the brain's freedom of movement, slosh injury is not addressed by these conventional methods [15,19]. ...
... Together, these injuries are known as, 'coup contrecoup injury' [17], and the mechanism of injury through which dynamic forces cause movement of the brain and its fluids within the skull is known as 'slosh' [6,15,19]. As most conventional protective methods, such as helmets, protect the skull but fail to mitigate the brain's freedom of movement, slosh injury is not addressed by these conventional methods [15,19]. To properly address slosh injury, protective methods must focus on the freedom of movement of the brain within the skull. ...
... Increases in intracranial volume cause a reduction in intracranial compliance thereby reducing the brain's movement within the skull, or slosh, and risk of TBI [6,15,19]. Of the components within the skull (the brain, CSF, and blood), blood is the component that is acquiescent to rapid changes in volume and, thereby pressure [15]. ...
Multiple species obtain repetitive head collisions throughout the course of their lifetimes with minimal neurologic deficit. Nature has allowed the unique development of multiple protective mechanisms to help prevent neurotrauma. In this review, we examine the concept of rapid brain movement within the skull 'Slosh' and what nature teaches on how to prevent this from occurring. We look at individual animals and the protective mechanisms at play. Marching from macroscopic down to the molecular level, we pinpoint key elements of neuroprotection that are likely contributing. We also introduce new concepts for neuroprotection and address avenues of further discovery.
... In addition, sub-concussive head impacts (SCIs), or impacts that do not result in overt clinical symptoms that lead to a clinical diagnosis of concussion, can elicit potentially deleterious neurophysiologic effects in athletes. 11,[26][27][28] Recent neuroimaging studies using diffusion tensor imaging (DTI) have shown significant changes to the diffusion and anisotropic properties of white matter (WM)-reflecting microstructural alterations in these pathways-after just one competitive sport season of football, 2,4,11,17,22,27 ice hockey, 3,26 and/or soccer. 28 Further, a systematic review of football, SCI exposure, and DTI revealed that the relative quantity and magnitude of athletes' SCI exposure is related to the degree of WM microstructural alterations, with greater cumulative exposure and load potentially being more injurious. ...
... In addition, sub-concussive head impacts (SCIs), or impacts that do not result in overt clinical symptoms that lead to a clinical diagnosis of concussion, can elicit potentially deleterious neurophysiologic effects in athletes. 11,[26][27][28] Recent neuroimaging studies using diffusion tensor imaging (DTI) have shown significant changes to the diffusion and anisotropic properties of white matter (WM)-reflecting microstructural alterations in these pathways-after just one competitive sport season of football, 2,4,11,17,22,27 ice hockey, 3,26 and/or soccer. 28 Further, a systematic review of football, SCI exposure, and DTI revealed that the relative quantity and magnitude of athletes' SCI exposure is related to the degree of WM microstructural alterations, with greater cumulative exposure and load potentially being more injurious. ...
... Although other methods exist to characterize the deleterious effects of SCIs on WM alterations, sensor-based kinematic assessment is the most prevalent method of in vivo SCI assessment in sport 4,11,[26][27][28] ; thus, accurate sensor-based SCI quantification is necessary when assessing neuroanatomical changes that potentially result from participation in contact sports, such as soccer, football, and lacrosse. In the present study, video confirmation revealed a high false positive rate and low accuracy (22.0%) when using thresholdbased filtering, indicating a steep overestimation of true SCI exposure. ...
Cumulative exposure to head impacts during contact sports can elicit potentially deleterious brain white matter alterations in young athletes. Head impact exposure is commonly quantified using wearable sensors; however, these sensors tend to overestimate the number of true head impacts that occur and may obfuscate potential relationships with longitudinal brain changes. The purpose of this study was to examine whether data-driven filtering of head impact exposure using machine learning classification could produce more accurate quantification of exposure and whether this would reveal more pronounced relationships with longitudinal brain changes. Season-long head impact exposure was recorded for 22 female high school soccer athletes and filtered using three methods—threshold-based, heuristic filtering, and machine learning (ML) classification. The accuracy of each method was determined using simultaneous video recording of a subset of the sensor-recorded impacts, which was used to confirm which sensor-recorded impacts corresponded with true head impacts and the ability of each method to detect the true impacts. Each filtered dataset was then associated with the athletes’ pre- and post-season MRI brain scans to reveal longitudinal white matter changes. The threshold-based, heuristic, and ML approaches achieved 22.0% accuracy, 44.6%, and 83.5% accuracy, respectively. ML classification also revealed significant longitudinal brain white matter changes, with negative relationships observed between head impact exposure and reductions in mean and axial diffusivity and a positive relationship observed between exposure and fractional anisotropy (all p < 0.05).
... More recently, specialized technologies have been developed to both record AE to head impacts and to diminish the consequences of these impacts. The earlier discussed specialized neck collar, designed to reduce intracranial energy absorption, has been shown to preserve white matter integrity in studies of football and hockey athletes [95,96]. In female high school soccer athletes, Myer et al. found microstructural changes in the white matter tracts on DTI in athletes who did not wear the collar device in comparison to athletes who wore the device [46]. ...
Sports-related concussion has been examined extensively in collision sports such as football and hockey. However, historically, lower-risk contact sports such as soccer have only more recently garnered increased attention. Here, we review articles examining the epidemiology, injury mechanisms, sex differences, as well as the neurochemical, neurostructural and neurocognitive changes associated with soccer-related concussion. From 436 titles and abstracts, 121 full texts were reviewed with a total of 64 articles identified for inclusion. Concussion rates are higher during competitions and in female athletes with purposeful heading rarely resulting in concussion. Given a lack of high-level studies examining sports-related concussion in soccer, clinicians and scientists must focus research efforts on large-scale data gathering and development of improved technologies to better detect and understand concussion.
