Eye Movements, Dizziness, and Mild Traumatic Brain Injury (mTBI): A Topical Review of Emerging Evidence and Screening Measures

Impacts of education level on Montreal Cognitive Assessment and saccades in community residents from Western China

OBJECTIVES

This cross-sectional study sought to evaluate the effectiveness of the Montreal Cognitive Assessment (MoCA) and saccade in discerning the cognitive function levels among community populations characterized by diverse educational backgrounds.

METHODS

Data from 665 Western China individuals encompassed MoCA scores and saccade performance. The study examined how education level and age influenced these assessments and highlighted the contrasting abilities of these measures in detecting cognitive abnormalities.

RESULTS

The saccade model revealed a consistent cognitive impairment prevalence (15.5%) compared to previous clinical data (9.7% to 23.3%), while MoCA exhibited variable rates (25.1% to 52.8%). Notably, saccades and MoCA significantly diverged in detecting cognitive dysfunction. Additionally, education level had a greater impact on MoCA (effect size: 0.272) compared to saccades (0.024) affecting all MoCA sub-items, with age exerting a smaller influence on MoCA (0.037) compared to saccades (0.056).

CONCLUSION

Saccades are less susceptible to the influence of education level when compared to MoCA, making saccade a potentially more suitable cognitive screening tool for rural community populations.

SIGNIFICANCE

This study represents a pioneering approach by employing saccade detection within community populations to distinguish cognitive function status.

Transient Acute Diplopia as a Rare Side Effect of Hydromorphone: A Case Report

Diplopia, or double vision, has been listed as a rare adverse effect of intravenous hydromorphone, although there are no case studies or literature documenting this. We detail a case of acute transient diplopia correlated with the use of intraoperative hydromorphone and postoperative hydromorphone patient-controlled analgesia. Although the mechanism for this adverse effect is unknown, there may be risk factors that predispose patients to the potential toxic metabolic effects of hydromorphone. We share the first published case of diplopia as a clinically relevant adverse effect of hydromorphone and propose a potential reason behind this association.

Post-Concussion Symptoms Rule: Derivation and Validation of a Clinical Decision Rule for Early Prediction of Persistent Symptoms after a Mild Traumatic Brain Injury

Mild traumatic brain injury (mTBI) is a common problem. Depending on diagnostic criteria, 13 to 62% of those patients develop persistent post-concussion symptoms (PPCS). The main objective of this prospective multi-center study is to derive and validate a clinical decision rule (CDR) for the early prediction of PPCS. Patients aged ≥14 years were included if they presented to one of our seven participating emergency departments (EDs) within 24 h of an mTBI. Clinical data were collected in the ED, and symptom evolution was assessed at 7, 30 and 90 days post-injury using the Rivermead Post-Concussion Questionnaire (RPQ). The primary outcome was PPCS at 90 days after mTBI. A predictive model called the Post-Concussion Symptoms Rule (PoCS Rule) was developed using the methodological standards for CDR. Of the 1083 analyzed patients (471 and 612 for the derivation and validation cohorts, respectively), 15.6% had PPCS. The final model included the following factors assessed in the ED: age, sex, history of prior TBI or mental health disorder, headache in ED, cervical sprain and hemorrhage on computed tomography. The 7-day follow-up identified additional risk factors: headaches, sleep disturbance, fatigue, sensitivity to light, and RPQ ≥21. The PoCS Rule had a sensitivity of 91.4% and 89.6%, a specificity of 53.8% and 44.7% and a negative predictive value of 97.2% and 95.8% in the derivation and validation cohorts, respectively. The PoCS Rule will help emergency physicians quickly stratify the risk of PPCS in mTBI patients and better plan post-discharge resources.

The University of Kansas Health System Outpatient Clinical Concussion Comprehensive Protocol: An Interdisciplinary Approach

Objective:

The concussion team at The University of Kansas Health System outpatient rehabilitation spine center is comprised of experienced multi-disciplinary experts including physical therapists and a speech language pathologist. The team set forth with a purpose of creating and organizing an internal physical therapy clinical recommendation protocol for initial evaluations and subsequent treatments for the concussed patient. The aim of this paper is to share these recommendation protocols with other therapy teams and provide a foundational layout for treating the patient with post-concussion symptoms in an outpatient physical therapy clinical setting.

Study design:

Clinical recommendation protocol provides guidance for patients ages 10+ from initial evaluation through discharge with emphasis on evidence-based research in the areas of: oculomotor, cervical, vestibular, post-concussion migraine influence, mood disorders(such as anxiety and depression), exertion, and cognitive communicative dysfunction.

Results:

Finding a written, comprehensive clinical resource protocol for post-concussion outpatient evaluation(s) and treatment strategies can be difficult. This document serves as a resource for other outpatient concussion rehabilitation clinics, providing rationale, and objective measurement tools, for assessing and treating concussion patients. To the authors’ knowledge, no other research has produced a practical, efficient evaluation tool to be utilized at bed side, condensing evidence-based research into an easy-to-use form.

Conclusion:

The University of Kansas Health System outpatient concussion rehabilitation center developed clinical recommendation protocols for concussion care. The intent was to standardize assessment and treatment for concussion patients and to share these objective measurement tools and procedures, focused on a team approach of concussion providers, as a clinical outline for both the novice and seasoned clinician specializing in the field of concussion work in an outpatient rehabilitation setting.

Pathway of care for visual and vestibular rehabilitation after mild traumatic brain injury: a critical review

PRIMARY OBJECTIVE

To review the pathway to care for treatment and management of patients receiving visual and vestibular rehabilitation after mild traumatic brain injury (mTBI).

METHODS & PROCEDURES

English scientific peer-reviewed articles from PubMed, CINAHL, Embase, and PsycINFO between 2000 and 2020 were first screened by title and abstract, then those selected underwent full-text review and analysis.

MAIN OUTCOMES & RESULTS

The database search yielded 1640 results and after title and abstract review, 75 articles were selected for full-text screening, from which 8 were included in the qualitative synthesis. Current evidence includes a limited number of retrospective cohort studies and case studies.

CONCLUSIONS

Many patients with visual and vestibular deficits following mTBI do not receive rehabilitation services until months following their injury as there is no standardized pathway to care for patients for visual and vestibular rehabilitation. Barriers to establishing a standardized pathway are the lack of natural history data for visual and vestibular function following mTBI and the lack of randomized clinical trials establishing the efficacy of rehabilitation in patients following mTBI.

Challenging the Vestibular System Affects Gait Speed and Cognitive Workload in Chronic Mild Traumatic Brain Injury and Healthy Adults

People with persistent symptoms after mild traumatic brain injury (mTBI) report imbalance during walking with head movements. The purpose of this study was (1) to compare usual walk gait speed to walking with head turns (HT) between people with mTBI and controls, (2) to compare the cognitive workload from usual walk to HT walk between groups, and (3) to examine if gaze stability deficits and mTBI symptoms influence gait speed. Twenty-three individuals (mean age 55.7 ± 9.3 years) with persistent symptoms after mTBI (between 3 months to 2 years post-injury) were compared with 23 age and sex-matched controls. Participants walked a 12-inch wide, 60-foot walkway when looking ahead and when walking with HT to identify letters and their colors. Gait speed during usual walk and HT walk were calculated. Pupillary responses during both walks were converted to the Index of Cognitive Activity (ICA) as a measure of cognitive workload. Gaze stability was examined by the dynamic visual acuity (DVA) test in the yaw plane. The post-concussion symptom scale (PCSS) was used to collect symptom severity. Within group analysis showed that gait speed was lower during HT walk compared to usual walk in the people with mTBI (p < 0.001) as well as in controls (p < 0.001). ICA was higher with HT compared to usual walk in the mTBI group in the right eye (p = 0.01) and left eye (p = 0.001), and in controls in the right eye (p = 0.01) and left eye (p = 0.01). Participants in the mTBI group had slower usual (p < 0.001), and HT gait speed (p < 0.001) compared to controls. No differences were noted in ICA in the right or left eye during usual walk and HT walk between groups (p > 0.05). DVA loss in the yaw plane to the right and left was not different between groups (p > 0.05) and were not correlated with gait speed. PCSS scores were correlated with usual walk (r = −0.50, p < 0.001) and HT gait speed (r = −0.44, p = 0.002). Slower gait speed, poorer stability, and higher cognitive workload during walking with head turns may reduce community participation in people with mTBI and persistent symptoms.

Vestibulo-ocular dysfunction in mTBI: Utility of the VOMS for evaluation and management – A review

BACKGROUND: Individuals who have suffered a concussion/mild traumatic brain injury (mTBI) frequently report symptoms associated with vestibular and/or oculomotor dysfunction (VOD) like dizziness, nausea, fatigue, brain fog, headache, gait and neurocognitive impairments which are associated with the development of chronic symptoms. The Vestibular/Ocular Motor Screening (VOMS) tool has been established as a reliable and clinically relevant complement to use alongside a battery of post-concussion tests to improve screening and referral for further evaluation and treatment of VOD. OBJECTIVES: This paper will review the pathoanatomy and symptomatology of common vestibular and oculomotor disorders after concussion, as well as the utility of the VOMS to assist in diagnosis, referral, and management. METHODS: Primary articles were identified using a search via PubMed, Google Scholar, OneSearch, and CINAHL. Search key terms were combinations of “mild traumatic brain injury” or “concussion” or “pursuit” or “accommodation” or “vergence” or “convergence insufficiency” or “saccades” or “vestibulo-ocular reflex” or “vestibular ocular motor screen” or “vestibular rehabilitation”, or “vision rehabilitation” including adult and pediatric populations that were published in print or electronically from 1989 to 2021 in English. Classic papers on anatomy of eye movements, vestibular system and pathological changes in mTBI were also included, regardless of publication date. RESULTS: Objective impairments are commonly found during testing of smooth pursuit, saccades, vergence, accommodation, vestibular ocular reflex, and visual motion sensitivity after mTBI. These deficits can be actively treated with vestibular physical therapy and oculomotor/neuro-optometric vision therapy. VOMS is an efficient and reliable tool that can be used by all healthcare and rehabilitation providers to aid in diagnosis of post-concussion VOD, to help facilitate the decision to refer for further evaluation and treatment to expedite symptomatic post-concussion recovery. CONCLUSIONS: VOD is common after concussion in acute, post-acute, and chronic phases. Once areas of impairments are identified through proper assessment, clinicians can maximize recovery by referring to vestibular physical therapy and/or neuro-optometry to design a targeted treatment program to address individual deficits.

Post-traumatic headaches and vision: A review

BACKGROUND: Post-traumatic headache is the most common sequela of brain injury and can last months or years after the damaging event. Many headache types are associated with visual concerns also known to stem from concussion. OBJECTIVES: To describe the various headache types seen after head injury and demonstrate how they impact or are impacted by the visual system. METHODS: We will mirror the International Classification of Headache Disorders (ICHD) format to demonstrate the variety of headaches following brain injury and relate correlates to the visual pathways. The PubMed database was searched using terms such as headache, head pain, vision, concussion, traumatic brain injury, glare, visuomotor pathways. RESULTS: Every type of headache described in the International Classification of Headache Disorders Edition III can be initiated or worsened after head trauma. Furthermore, there is very often a direct or indirect impact upon the visual system for each of these headaches. CONCLUSION: Headaches of every described type in the ICHD can be caused by brain injury and all are related in some way to the afferent, efferent or association areas of the visual system.

Neuro-Visual and Vestibular Manifestations of Concussion and Mild TBI

PURPOSE OF REVIEW

Mild traumatic brain injury, or concussion, is a major cause of disability. Vestibular and visual dysfunction following concussion is common and can negatively affect patients' well-being and prolong recovery. Etiologies of visual and vestibular symptoms are numerous, including ocular, neuro-ophthalmic, otologic, and neuro-vestibular conditions. Some etiologies are benign and may be treatable, while others are potentially vision or life-threatening, making a focused history and examination essential. This review offers an approach to the evaluation and treatment of the most common neuro-visual and vestibular impairments that may result from concussion.

RECENT FINDINGS

Treatment of concussion including exercise, computerized programs, transcranial magnetic stimulation, gene therapy, stem cell therapy, and nanoparticles has shown promise. Many novel therapies are in the pipework for visual and vestibular recovery after concussion; however, the treatment mainstay remains therapy and evaluation for co-existing diseases.

Vestibular Rehabilitation Telehealth During the SAEA-CoV-2 (COVID-19) Pandemic

During the COVID-19 pandemic, physical therapists transitioned to provide telehealth in the United States. We sought to determine the experiences of physical therapists delivering telerehabilitation for vestibular disorders including barriers, preferences, and concerns. A survey was created using the results of a focus group and previously published studies. The survey was distributed across social media sites and through email- the link was sent to the orthopedic, neurologic, and geriatric academies of the American Physical Therapy Association list serves. The email was also shared with each of the 50 state chapters of the American Physical Therapy Association. The survey was broken down into five sections: demographic information, physical therapists' general impressions of telehealth, physical therapists' comfort level treating various vestibular diagnoses, and common barriers physical therapists experienced during telehealth sessions. There were 159 completed surveys. More than 80% of physical therapists surveyed agreed that telehealth was an effective platform for vestibular physical therapy. When asked whether physical therapists felt the patient had similar health outcomes with telehealth versus clinic care 68% of physical therapists agreed. For the physical therapists who treated posterior or horizontal canal benign paroxysmal positional vertigo via telehealth, more than 50% were comfortable treating these conditions via telehealth. In analyzing common peripheral vestibular diagnoses treated via telehealth including bilateral vestibular loss, Meniere's disease, and vestibular neuritis more than 75% of the physical therapists reported comfort treating these diagnoses. Similarly, more than 75% of physical therapists who treated central vestibular diagnoses- including mild traumatic brain injury and vestibular migraine- via telehealth reported being comfortable treating these diagnoses. Physical therapists reported several barriers to tele healthcare ranging from concerns about testing balance with no caregiver present (94%) to challenges with providing a written home exercise program (33%). Physical therapists report that telehealth is a viable mechanism for providing rehabilitation for persons with balance and vestibular disorders. For common diagnoses, most physical therapists were comfortable treating vestibular disorders via telehealth. While barriers remain including maintaining patient safety and being able to complete a thorough vestibular exam, telehealth for vestibular physical therapy services holds promise for the delivery of virtual care.

Saccade and Fixation Eye Movements During Walking in People With Mild Traumatic Brain Injury

Background: Clinical and laboratory assessment of people with mild traumatic brain injury (mTBI) indicate impairments in eye movements. These tests are typically done in a static, seated position. Recently, the use of mobile eye-tracking systems has been proposed to quantify subtle deficits in eye movements and visual sampling during different tasks. However, the impact of mTBI on eye movements during functional tasks such as walking remains unknown.

Objective: Evaluate differences in eye-tracking measures collected during gait between healthy controls (HC) and patients in the sub-acute stages of mTBI recovery and to determine if there are associations between eye-tracking measures and gait speed.

Methods: Thirty-seven HC participants and 67individuals with mTBI were instructed to walk back and forth over 10-m, at a comfortable self-selected speed. A single 1-min trial was performed. Eye-tracking measures were recorded using a mobile eye-tracking system (head-mounted infra-red Tobbii Pro Glasses 2, 100 Hz, Tobii Technology Inc. VA, United States). Eye-tracking measures included saccadic (frequency, mean and peak velocity, duration and distance) and fixation measurements (frequency and duration). Gait was assessed using six inertial sensors (both feet, sternum, right wrist, lumbar vertebrae and the forehead) and gait velocity was selected as the primary outcome. General linear model was used to compare the groups and association between gait and eye-tracking outcomes were explored using partial correlations.

Results: Individuals with mTBI showed significantly reduced saccade frequency (p = 0.016), duration (p = 0.028) and peak velocity (p = 0.032) compared to the HC group. No significant differences between groups were observed for the saccade distance, fixation measures and gait velocity (p > 0.05). A positive correlation was observed between saccade duration and gait velocity only for participants with mTBI (p = 0.025).

Conclusion: Findings suggest impaired saccadic eye movement, but not fixations, during walking in individuals with mTBI. These findings have implications in real-world function including return to sport for athletes and return to duty for military service members. Future research should investigate whether or not saccade outcomes are influenced by the time after the trauma and rehabilitation.

The development and the inter-rater agreement of a treatment protocol for vestibular/oculomotor rehabilitation in children and adolescents post-moderate-severe TBI

Introduction:There is limited evidence investigating the effect of vestibular/oculomotor rehabilitation programs in children and adolescents post moderate-severe TBI at the sub-acute stage.Objective:To describe the development of a treatment protocol for vestibular/oculomotor interventions in this population, and to assess the inter-rater agreement of this protocol as an initial step of a clinical trial.Method:The protocol was developed by 10 health professionals, address the high variability of balance performance, the high prevalence of vestibular/oculomotor abnormalities and the low prevalence of symptoms reported in this population.Results:The protocol enables the clinician to use the assessment during the treatment exercise selection. The training position was defined by the Pediatric Balance Scale. Vestibular/oculomotor exercises were selected using a quantified version of the Vestibular/Ocular Motor Screening. The exercise protocol was selected based on impairment in function or reproduction of symptoms. The protocol planning was implemented by two assessors in 27 children and adolescents post-moderate-severe TBI (median age 14.1 [6-18.4] years) in the sub-acute stage (median 40 [14-162] days since injury). Very high agreement was found (k > 0.72) in all the parameters.Conclusion: This protocol could reliably be used in a randomized control trial that assesses the effect of vestibular/oculomotor rehabilitation program in children and adolescents post moderate-severe TBI at the sub-acute stage.

Vestibular, Oculomotor, and Balance Functions in Children With and Without Concussion

OBJECTIVE

The main objective of this study was to assess whether objective vestibular, oculomotor, and balance functions were impaired in children with a current diagnosis of concussion with vestibular and/or ocular symptoms.

SETTING

Data were collected in a vestibular/ocular clinical laboratory. Patient participants were recruited from a concussion clinic in a children's hospital.

PARTICIPANTS

Thirty-three children aged 8 to 17 years with a current diagnosis of concussion and vestibular and/or ocular symptoms and 30 children without concussion.

DESIGN

Cross-sectional single-visit study.

MAIN OUTCOME MEASURES

Eye-tracking rotary chair oculomotor and vestibular measures, vestibular evoked potentials, and static posturography.

RESULTS

There were no statistically significant differences on any clinical measure between children with concussion and children without concussion. Younger children without concussion performed significantly worse on several rotary chair and balance measures compared with older children without concussion.

CONCLUSIONS

No vestibular, oculomotor, or balance measures were significantly different between children with concussion and children without concussion, suggesting these measures may not be useful in the evaluation of a child with concussion and vestibular and/or oculomotor symptoms. Future research should investigate age effects and other vestibular and oculomotor tests to identify objective findings that better relate to vestibular and/or ocular symptoms in children with concussion.

Oculomotor Training for Poor Saccades Improves Functional Vision Scores and Neurobehavioral Symptoms

OBJECTIVES

To determine if participants with saccadic dysfunction improved after participating in a standardized oculomotor training program. A secondary objective was to accurately quantify change in saccades after training using eye tracking technology. A third objective was to examine patients' neurobehavioral symptoms before and after oculomotor training using the Neurobehavioral Symptom Inventory (NSI).

DESIGN

A prospective study involving treatment and control group pre-post intervention design.

SETTING

Data were collected in eye clinics with a standardized eye tracking equipment setup.

PARTICIPANTS

Participants in the bottom 25th percentile for saccadic eye movements (N=92; intervention=46, control=46) who were currently asymptomatic of specific disorder.

INTERVENTIONS

Participants were randomly assigned to the control or intervention group. The intervention group engaged in 10 minutes of oculomotor training daily for 5 days.

MAIN OUTCOME MEASURES

The ratio of the peak saccadic velocity over its average velocity (the Q ratio), saccadic targeting, and NSI.

RESULTS

Results revealed significant interactions between control and intervention groups (P=.013). The control group increased 7% from pre to post; however, the intervention group exhibited a 6% decreased from pre to post. Participants in the intervention group demonstrated a 25% improvement in targeting saccade accuracy (P=.021). Additionally, there was a significant reduction in all neurobehavioral factors on the NSI in the intervention group, specifically the affective and cognitive factors relating to poor saccades.

CONCLUSIONS

For this population, oculomotor training (Q ratio and saccade accuracy) resulted improved saccadic metrics and a significant reduction in overall symptoms as shown on the NSI. Future participants reported improved symptoms pre- and postintervention. Further research is needed to understand saccadic performance and gaze stability during specific tasks (such as reading).

Vestibular-ocular reflex dysfunction following mild traumatic brain injury: A narrative review

Mild traumatic brain injury (mTBI) is a prevalent injury which occurs across many populations, including children and adolescents, athletes, military personnel, and the elderly. mTBI can result in various subjective symptoms and clinical deficits, such as abnormalities to the vestibulo-ocular reflex (VOR). Over 50% of individuals with mTBI are reported to have VOR abnormalities, which strongly contribute to feelings of dizziness and unsteadiness. Dizziness is a strong predictor for prolonged recovery following mTBI and is additionally linked with mental health difficulties and functional limitations affecting likelihood of return to work. Early diagnosis, and subsequent treatment, of VOR deficits following mTBI may greatly improve recovery outcomes and a patient's quality of life, but a thorough comprehension of the related pathophysiology is necessary to understand the assessments used to diagnose VOR abnormalities. Therefore, the purpose of this article is i) provide readers with an introduction on the VOR physiology to facilitate understanding about mTBI-related abnormalities, and ii) to discuss current assessments that are commonly used to measure VOR function following mTBI. As the VOR and oculomotor (OM) systems are heavily linked and often work in tandem, discussion of the relevant aspects of the OM system is also provided.

Measuring optokinetic after-nystagmus: potential for detecting patients with signs of visual dependence following concussion

Concussed patients with chronic symptoms commonly report dizziness during exposure to environments with complex visual stimuli (e.g. supermarket aisles, busy crossroads). Such visual induced dizziness is well-known in patients with vestibular deficits, in whom it indicates an overreliance on visual cues in sensory integration. Considering that optokinetic after-nystagmus (OKAN) reflects the response of the central network integrating visual and vestibular self-motion signals (velocity storage network), we investigated OKAN in 71 patients [17 (23.9%) females, 30.36 ± 9.05 years old] who suffered from persistent symptoms after a concussion and presented clinical signs suggesting visual dependence. Data were retrospectively compared with 21 healthy individuals [13 (61.9%) females, 26.29 ± 10.00 years old]. The median values of the slow cumulative eye position and of the time constant of OKAN were significantly higher in patients than in healthy individuals (slow cumulative eye position: 124.15 ± 55.61° in patients and 77.87 ± 45.63° in healthy individuals—p = 0.012; time constant: 25.17 ± 10.27 s in patients and 13.95 ± 4.92 s in healthy individuals—p = 0.003). The receiving operating curve (ROC) estimated on the time constant had an overall area under the curve of 0.73. Analysis of the ROC suggests that a test measuring the OKAN time constant could obtain a sensitivity of 0.73 and specificity of 0.72 in determining the origin of the visual-related disturbances in those patients (threshold 16.6 s). In a subset of 43 patients who also performed the Sensory Organization Test (SOT), the proposed OKAN test was twice as sensitive as the SOT. This study suggests that concussed patients with persisting visual symptoms may have an underlying impairment of the velocity storage mechanism and that measuring the OKAN time constant can objectify such impairment.

A commentary for neuropsychologists on CDC's guideline on the diagnosis and management of mild traumatic brain injury among children

Objective: In 2018, the Centers for Disease Control Prevention (CDC) published an evidence-based guideline on the diagnosis and management of mild traumatic brain injury (mTBI) among children. This commentary summarizes the key recommendations in the CDC Pediatric mTBI Guideline most relevant for neuropsychologists and discusses research gaps and topics that should receive attention in future iterations of the Guideline.Method: We described the methods used to develop the Guideline, which included a comprehensive Systematic Review. We also distilled and presented key practice strategies reflected in Guideline.Results: To optimize care of pediatric patients with mTBI, neuropsychologists should: use validated, age-appropriate symptom scales, assess evidence-based risk factors for prolonged recovery, provide patients with instructions on return to activity customized to their symptoms, and counsel patients to return gradually to nonsports activities after a short period of rest. Future iterations of the Guideline should encompass a review and guidance on care of patients with psychiatric and psychological difficulties, as well as the potential use of imaging to assess patients with persistent symptoms. Expanded research on mTBI among girls, children age 8 and under, and effective treatments for pediatric mTBI will be beneficial to inform care practices.Conclusions: Recommendations in the CDC Pediatric mTBI Guideline highlight multiple opportunities for neuropsychologists to take action to improve the care of young patients with mTBI and to advance research in the field. Multiple resources and tools are available to support implementation of these recommendations into clinical practice.

The Measurement of Eye Movements in Mild Traumatic Brain Injury: A Structured Review of an Emerging Area

Mild traumatic brain injury (mTBI), or concussion, occurs following a direct or indirect force to the head that causes a change in brain function. Many neurological signs and symptoms of mTBI can be subtle and transient, and some can persist beyond the usual recovery timeframe, such as balance, cognitive or sensory disturbance that may pre-dispose to further injury in the future. There is currently no accepted definition or diagnostic criteria for mTBI and therefore no single assessment has been developed or accepted as being able to identify those with an mTBI. Eye-movement assessment may be useful, as specific eye-movements and their metrics can be attributed to specific brain regions or functions, and eye-movement involves a multitude of brain regions. Recently, research has focused on quantitative eye-movement assessments using eye-tracking technology for diagnosis and monitoring symptoms of an mTBI. However, the approaches taken to objectively measure eye-movements varies with respect to instrumentation, protocols and recognition of factors that may influence results, such as cognitive function or basic visual function. This review aimed to examine previous work that has measured eye-movements within those with mTBI to inform the development of robust or standardized testing protocols. Medline/PubMed, CINAHL, PsychInfo and Scopus databases were searched. Twenty-two articles met inclusion/exclusion criteria and were reviewed, which examined saccades, smooth pursuits, fixations and nystagmus in mTBI compared to controls. Current methodologies for data collection, analysis and interpretation from eye-tracking technology in individuals following an mTBI are discussed. In brief, a wide range of eye-movement instruments and outcome measures were reported, but validity and reliability of devices and metrics were insufficiently reported across studies. Interpretation of outcomes was complicated by poor study reporting of demographics, mTBI-related features (e.g., time since injury), and few studies considered the influence that cognitive or visual functions may have on eye-movements. The reviewed evidence suggests that eye-movements are impaired in mTBI, but future research is required to accurately and robustly establish findings. Standardization and reporting of eye-movement instruments, data collection procedures, processing algorithms and analysis methods are required. Recommendations also include comprehensive reporting of demographics, mTBI-related features, and confounding variables.