Classification of Comprehensive Neuro-Ophthalmologic Measures of Postacute Concussion

Comparing return to play protocols after sports-related concussion among international sporting organisations

BACKGROUND

Return to play (RTP) protocols are an important part of recovery management following a sport-related concussion (SRC) and can prevent athletes from returning to competition too early and thereby avoid prolonged recovery times. To assist sporting organizations in the development of RTP guidelines, the Concussion in Sports Group (CISG) provides scientific-based recommendations for the management of SRC in its consensus statement on concussion in sport.

OBJECTIVES

This study investigates commonalities and differences among current RTP protocols of international sporting organizations and examines the implementation of the most recent CISG recommendations.

METHODS

Concussion guidelines and medical rules of 12 international sporting organizations from contact, collision and combat sports were accessed via the organizations websites and compared regarding the management of SRC and the RTP decision.

RESULTS

Only six of the included organizations developed and published their own concussion guidelines, which included an RTP protocol on their website. The number of steps until RTP was similar across the different protocols. Each protocol required at least one medical examination before clearing an athlete to RTP. A high variation among organizations was found for initial resting period after injury, the implementation of sport-specific training drills and the time needed to complete the protocol before returning to competition. At the date of this study (9 September 2023), none of the accessible RTP protocols were updated to include the latest version of the CISG consensus statement.

CONCLUSION

To improve the safety of athletes after a head injury, sporting organizations should develop sport-specific guidelines according to the latest CISG consensus statement, and this should be updated regularly. Implementation is especially important in combat sports, where there is a high incidence of head injury. Thus, there is a requirement for the most up-to-date concussion management protocols in these sports.

Psychometric Properties of Vestibular and Ocular Measures Used for Concussion Assessments: A Scoping Review

BACKGROUND

Concussions most commonly affect the vestibular and ocular systems. Clinical measures used in the assessment of vestibular and ocular deficits should contain strong psychometric properties so that clinicians can accurately detect abnormality to guide treatment interventions.

OBJECTIVES

The aim of this scoping review was: (1) to identify the measures used to evaluate the vestibular and ocular domains postconcussion and (2) to document the psychometric properties of the measures.

METHODS

Two databases (Medline (Ovid) and Embase) were searched from inception to May 2023. An updated search was completed in January 2024 using the same databases and search terms. Studies were screened and data were extracted independently by 2 reviewers. Measures were categorized into vestibular, ocular, or both (vestibular and ocular) domains, and relevant psychometric properties were documented.

RESULTS

Fifty-two studies were included in this review. 28 studies explored the use of vestibular measures, 12 explored ocular measures, and 12 explored both vestibular and ocular measures or explored the use of vestibulo-ocular reflex measures. Most studies explored the properties associated with balance measures, particularly the balance error scoring system. Diagnostic accuracy (sensitivity and specificity metrics) of the associated measures was the most frequently documented characteristic in the literature.

CONCLUSION

Identification of clinical measures used to evaluate vestibular and ocular deficits postconcussion is needed to understand the evidence supporting their use in practice. Documenting the psychometric properties will allow clinicians and researchers to understand the status of the current literature and support for the use of certain measures in practice in terms of their ability to appropriately detect deficits in people with concussion when deficits are truly present.

Clinical Utility of Ocular Assessments in Sport-Related Concussion: A Scoping Review

Background/objectives: Ocular tools and technologies may be used in the diagnosis of sport-related concussions (SRCs), but their clinical utility can vary. The following study aimed to review the literature pertaining to the reliability and diagnostic accuracy of such assessments. Methods: The preferred reporting items for systematic reviews and meta-analysis (PRISMA) extension for scoping reviews was adhered to. Reference standard reliability (RSR ≥ 0.75) and diagnostic accuracy (RSDA ≥ 0.80) were implemented to aid interpretation. Results: In total, 5223 articles were screened using the PCC acronym (Population, Concept, Context) with 74 included in the final analysis. Assessments included the King-Devick (KD) (n = 34), vestibular-ocular motor screening (VOMs) and/or near point of convergence (NPC) (n = 25), and various alternative tools and technologies (n = 20). The KD met RSR, but RSDA beyond amateur sport was limited. NPC met RSR but did not have RSDA to identify SRCs. The VOMs had conflicting RSR for total score and did not meet RSR in its individual tests. The VOMs total score did perform well in RSDA for SRCs. No alternative tool or technology met both RSR and RSDA. Conclusion: Ocular tools are useful, rapid screening tools but should remain within a multi-modal assessment for SRCs at this time.

Biofluid, Imaging, Physiological, and Functional Biomarkers of Mild Traumatic Brain Injury and Subconcussive Head Impacts

Post-concussive symptoms are frequently reported by individuals who sustain mild traumatic brain injuries (mTBIs) and subconcussive head impacts, even when evidence of intracranial pathology is lacking. Current strategies used to evaluate head injuries, which primarily rely on self-report, have a limited ability to predict the incidence, severity, and duration of post-concussive symptoms that will develop in an individual patient. In addition, these self-report measures have little association with the underlying mechanisms of pathology that may contribute to persisting symptoms, impeding advancement in precision treatment for TBI. Emerging evidence suggests that biofluid, imaging, physiological, and functional biomarkers associated with mTBI and subconcussive head impacts may address these shortcomings by providing more objective measures of injury severity and underlying pathology. Interest in the use of biomarker data has rapidly accelerated, which is reflected by the recent efforts of organizations such as the National Institute of Neurological Disorders and Stroke and the National Academies of Sciences, Engineering, and Medicine to prioritize the collection of biomarker data during TBI characterization in acute-care settings. Thus, this review aims to describe recent progress in the identification and development of biomarkers of mTBI and subconcussive head impacts and to discuss important considerations for the implementation of these biomarkers in clinical practice.

Precision Concussion Management: Approaches to Quantifying Head Injury Severity and Recovery

Mitigating the substantial public health impact of concussion is a particularly difficult challenge. This is partly because concussion is a highly prevalent condition, and diagnosis is predominantly symptom-based. Much of contemporary concussion management relies on symptom interpretation and accurate reporting by patients. These types of reports may be influenced by a variety of factors for each individual, such as preexisting mental health conditions, headache disorders, and sleep conditions, among other factors. This can all be contributory to non-specific and potentially misleading clinical manifestations in the aftermath of a concussion. This review aimed to conduct an examination of the existing literature on emerging approaches for objectively evaluating potential concussion, as well as to highlight current gaps in understanding where further research is necessary. Objective assessments of visual and ocular motor concussion symptoms, specialized imaging techniques, and tissue-based concentrations of specific biomarkers have all shown promise for specifically characterizing diffuse brain injuries, and will be important to the future of concussion diagnosis and management. The consolidation of these approaches into a comprehensive examination progression will be the next horizon for increased precision in concussion diagnosis and treatment.

Role of biomarkers and emerging technologies in defining and assessing neurobiological recovery after sport-related concussion: a systematic review

OBJECTIVE

Determine the role of fluid-based biomarkers, advanced neuroimaging, genetic testing and emerging technologies in defining and assessing neurobiological recovery after sport-related concussion (SRC).

DESIGN

Systematic review.

DATA SOURCES

Searches of seven databases from 1 January 2001 through 24 March 2022 using keywords and index terms relevant to concussion, sports and neurobiological recovery. Separate reviews were conducted for studies involving neuroimaging, fluid biomarkers, genetic testing and emerging technologies. A standardised method and data extraction tool was used to document the study design, population, methodology and results. Reviewers also rated the risk of bias and quality of each study.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Studies were included if they: (1) were published in English; (2) represented original research; (3) involved human research; (4) pertained only to SRC; (5) included data involving neuroimaging (including electrophysiological testing), fluid biomarkers or genetic testing or other advanced technologies used to assess neurobiological recovery after SRC; (6) had a minimum of one data collection point within 6 months post-SRC; and (7) contained a minimum sample size of 10 participants.

RESULTS

A total of 205 studies met inclusion criteria, including 81 neuroimaging, 50 fluid biomarkers, 5 genetic testing, 73 advanced technologies studies (4 studies overlapped two separate domains). Numerous studies have demonstrated the ability of neuroimaging and fluid-based biomarkers to detect the acute effects of concussion and to track neurobiological recovery after injury. Recent studies have also reported on the diagnostic and prognostic performance of emerging technologies in the assessment of SRC. In sum, the available evidence reinforces the theory that physiological recovery may persist beyond clinical recovery after SRC. The potential role of genetic testing remains unclear based on limited research.

CONCLUSIONS

Advanced neuroimaging, fluid-based biomarkers, genetic testing and emerging technologies are valuable research tools for the study of SRC, but there is not sufficient evidence to recommend their use in clinical practice.

PROSPERO REGISTRATION NUMBER

CRD42020164558.

Portable eye-tracking as a reliable assessment of oculomotor, cognitive and reaction time function: Normative data for 18-45 year old

Eye movements measured by high precision eye-tracking technology represent a sensitive, objective, and non-invasive method to probe functional neural pathways. Oculomotor tests (e.g., saccades and smooth pursuit), tests that involve cognitive processing (e.g., antisaccade and predictive saccade), and reaction time tests have increasingly been showing utility in the diagnosis and monitoring of mild traumatic brain injury (mTBI) in research settings. Currently, the adoption of these tests into clinical practice is hampered by a lack of a normative data set. The goal of this study was to construct a normative database to be used as a reference for comparing patients' results. Oculomotor, cognitive, and reaction time tests were administered to male and female volunteers, aged 18-45, who were free of any neurological, vestibular disorders, or other head injuries. Tests were delivered using either a rotatory chair equipped with video-oculography goggles (VOG) or a portable virtual reality-like VOG goggle device with incorporated infrared eye-tracking technology. Statistical analysis revealed no effects of age on test metrics when participant data were divided into pediatric (i.e.,18-21 years, following FDA criteria) and adult (i.e., 21-45 years) groups. Gender (self-reported) had an effect on auditory reaction time, with males being faster than females. Pooled data were used to construct a normative database using 95% reference intervals (RI) with 90% confidence intervals on the upper and lower limits of the RI. The availability of these RIs readily allows clinicians to identify specific metrics that are deficient, therefore aiding in rapid triage, informing and monitoring treatment and/or rehabilitation protocols, and aiding in the return to duty/activity decision. This database is FDA cleared for use in clinical practice (K192186).