Search

BACKGROUND: Clinical vestibular technology is rapidly evolving to improve objective assessments of vestibular function. Understanding the reliability and expected score ranges of emerging clinical vestibular tools is important to gauge how these tools should be used as clinical endpoints. OBJECTIVE: The objective of this study was to evaluate inter-rater and test-retest reliability intraclass correlation coefficients (ICCs) of four vestibular tools and to determine expected ranges of scores through smallest real difference (SRD) measures. METHODS: Sixty healthy graduate students completed two 1-hour sessions, at most a week apart, consisting of two video head-impulse tests (vHIT), computerized dynamic visual acuity (cDVA) tests, and a smartphone-assisted bucket test (SA-SVV). Thirty students were tested by different testers at each session (inter-rater) and 30 by the same tester (test-retest). ICCs and SRDs were calculated for both conditions. RESULTS: Most measures fell within the moderate ICC range (0.50–0.75). ICCs were higher for cDVA in the inter-rater subgroup and higher for vHITs in the test-retest subgroup. CONCLUSIONS: Measures from the four tools evaluated were moderately reliable. There may be a tester effect on reliabilities, specifically vHITs. Further research should repeat these analyses in a patient population and explore methodological differences between vHIT systems.

Orthostatic intolerance (OI) following pediatric concussion is not well understood. Assessing the prevalence of concussion-related OI and how it compares to non-concussion-related OI will improve care for patients suffering with these symptoms. OBJECTIVE: We set out to describe concussion-related OI in adolescence, with particular emphasis on time to recovery and differences from non-concussion-related OI (including male vs. female prevalence). Retrospective chart reviews were completed on post-concussion patients endorsing symptoms of OI. The patients' sex, sport history, previous concussions, time since injury, and recovery time were analyzed and compared between males and females as well as against general OI statistics. Thirty-nine pediatric patients, representing 8.7% of all new patients referred to a specialized concussion clinic over a 13-month interval, were included in the chart review. Mean age of onset was 15.0 ± 2.5 years and 18 (46%) were males. The median times from evaluation to symptom resolution were 120 days. Of 18 patients who completed head-up tilt table testing, 17 (94%) had orthostatic tachycardic response (>40 bpm heart rate increment). Post-concussive OI differs from other orthostatic intolerance etiologies, lacking a strong female predominance and exhibiting a shorter time course to recovery compared to other etiologies of OI (but longer recovery time compared to concussion patients in general). Clinical orthostatic vital signs may not be sensitive for diagnosing orthostatic intolerance in athletes, likely due to higher vagal tone and more efficient skeletal muscle pump.

Background and purpose Balance disorders and dizziness are common in people with multiple sclerosis (MS), suggesting dysfunction of the vestibular system. Evaluating how people with MS perform on objective clinical vestibular tools will help broaden understanding of vestibular function in MS. This cross-sectional study's goal was to complete a robust battery of vestibular-ocular reflex (VOR), dynamic visual acuity (DVA), subjective visual vertical (SVV), and cervical and ocular vestibular-evoked myogenic potential (c/oVEMP) tests in people with and without MS. Methods Forty people with relapsing-remitting MS (Expanded Disability Status Scale [EDSS] ≤6.5) and 20 controls completed the vestibular testing battery. Results were compared between groups and correlations with EDSS scores were calculated. Results People with MS were less able to visually cancel their VOR and showed a larger variance in response on SVV. EDSS significantly correlated with VOR cancellation, SVV variance, and DVA lines lost; linear regression showed that VOR cancellation and SVV variance significantly predicted EDSS. Discussion and conclusion Vestibular functions requiring central integration of vestibular information, but not reflexive vestibular functions like VEMP, were impaired in people with MS and correlated with EDSS, suggesting that clinical evaluation of functions requiring central integration best evaluates MS-related vestibular dysfunction. Measures assessing central vestibular integration and not vestibular reflexes may be more sensitive to detecting vestibular deficits in people with mild to moderate MS.Video Abstract available for more insight from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A344).

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.

Background. Cognitive impairment is common, but poorly managed in people with multiple sclerosis (MS). Balance has been correlated with cognition in people with MS, potentially through shared utilization of central sensory integration pathways. Objective. This study characterized the relationship between central vestibular integration and cognition in people with MS through measurement of several clinical vestibular functions requiring central sensory integration and multiple cognitive domains. Methods. Forty people with MS and 20 controls completed a battery of vestibular and cognitive examinations targeting different central vestibular integration measures and different domains of cognition, respectively. Performance on these measures was compared between people with MS and controls, and then correlational analyses were undertaken between the vestibular and cognitive measures in the MS sample. Results. People with MS performed worse than controls on all vestibular and cognitive measures. There were consistent correlations between vestibular and cognitive measures in the MS sample. Factor analysis of vestibular functions yielded a single factor hypothesized to represent central vestibular integration that demonstrated a significant relationship with a composite cognitive measure in people with MS. Discussion. Our results suggest that vestibular and cognitive dysfunction may both arise from central sensory processing pathways in people with MS. This connection could be targeted through vestibular rehabilitation techniques that improve central sensory processing and both balance and cognition in people with MS.

BACKGROUND AND PURPOSE According to the most recent consensus statement on management of sport-related concussion (SRC), athletes with suspected SRC should receive a comprehensive neurological examination. However, which measures to include in such an examination are not defined. Our objectives were to (1) evaluate test-retest reliability and normative data on vestibular and balance tests in athletes without SRC; (2) compare athletes with and without SRC on the subtests; and (3) identify subtests for concussion testing protocols. METHODS Healthy athletes (n = 87, mean age 20.6 years; standard deviation = 1.8 years; 39 female and 48 male) and athletes with SRC (n = 28, mean age 20.7 years; standard deviation = 1.9 years; 11 female and 17 male) were tested using rotary chair, cervical vestibular-evoked myogenic potential (c-VEMP), and the Sensory Organization Test (SOT). A subset (n = 43) were tested twice. We analyzed reliability of the tests, and compared results between athletes with and without SRC. RESULTS Reliability ranged from poor to strong. There was no significant difference between athletes with and without SRC for tests of peripheral vestibular function (ie, rotary chair and c-VEMP). Athletes with SRC had significantly worse scores (P < 0.05) on vestibular-ocular reflex (VOR) cancellation gain, subjective visual vertical and horizontal variance, and all conditions of the SOT. DISCUSSION AND CONCLUSION SRC did not affect medium frequency VOR or saccular function. SRC did affect the ability to use vestibular inputs for perception of vertical and postural control, as well as ability to cancel the VOR.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A274).

SIGNIFICANCE. Oculomotor tests in concussion commonly show impairment in smooth pursuit and saccadic function. Honing in on the systems likely to be affected by concussion will streamline use of oculomotor function as a supplemental diagnostic and prognostic tool, as well as improve our understanding of the pathophysiology of concussion. PURPOSE. This study investigates oculomotor function between concussed and healthy collegiate athletes, as well as determines measurement test-retest reliability of those tools. METHODS. Eighty-seven healthy athletes were recruited from a US Division 1 sports university and completed a 30-minute vestibular ocular testing battery in an enclosed rotary chair system equipped with 100Hz eye-tracking goggles. Forty-three individuals completed the battery twice. Twenty-eight individuals with a current diagnosis of concussion also completed the battery. All participants were ages 18–24. Bivariate statistical tests examined differences in scores across groups, and intraclass coefficients were computed to test reliability. RESULTS. Concussed individuals had significantly longer saccadic, visual, and dual-task reaction times and reduced saccadic accuracy. There was no difference in optokinetic reflex gain, but few concussed individuals tolerated the task. Reaction time latencies and optokinetic gain show moderate test-retest reliability. Smooth pursuit tasks and saccadic accuracies showed poor test-retest reliability. CONCLUSIONS. Saccadic latency was the most sensitive oculomotor function to change following concussion and was reliable over time. Saccadic accuracy was significantly lower in the concussed group but had poor retest-reliability. Optokinetic gain may warrant more investigation due to its high test-retest reliability and symptom provocation in concussion, despite not showing a significant difference between groups.

Objective Imbalance and fatigue are among the most common and disabling symptoms of multiple sclerosis (MS). Vestibular rehabilitation studies demonstrate not only improvements in balance but fatigue also, suggesting a relationship between central vestibular integration and fatigue. The objective of this study was to determine whether the relationship between balance and fatigue in people with MS is seen between other measures of central vestibular integration and fatigue and to understand how central vestibular integration measures interrelate. Methods This cross-sectional study consisted of 40 people with MS (age = 27–55 years, Expanded Disability Severity Scale score = 1.0–6.5) who completed vestibular ocular reflex testing, subjective visual vertical testing, static posturography, dynamic gait, 2 self-report fatigue surveys, and a 6-Minute Walk Test to assess walking capacity/physical fatigue was completed. Spearman correlations were calculated between variables. Results Measures of central vestibular integration were significantly correlated with measures of fatigue and walking capacity and with each other. The correlations between physical fatigue and central vestibular functions were larger than self-reported fatigue correlations with central vestibular functions. Conclusion The relationship between balance and fatigue extends to other measures requiring central vestibular integration, suggesting a deficit in central vestibular processing in people with MS. These measures may compliment balance assessment as outcome measures for vestibular rehabilitation in people with MS. Fatigue measures should be included in vestibular rehabilitation as secondary outcomes. Impact Correlations between central vestibular integration and fatigue in people with MS suggest that future studies of vestibular rehabilitation should include fatigue, as a secondary outcome measure as vestibular function and fatigue may share similar a similar etiology in people with MS.

BACKGROUND AND OBJECTIVES:Congenital cytomegalovirus (cCMV) is the leading nongenetic cause of sensorineural hearing loss and developmental disabilities. Because there are limited data from studies of vestibular involvement in select groups of children with cCMV, the true frequency of vestibular disorders in cCMV is likely underestimated. Our objective for this study is to determine the prevalence of vestibular, gaze, and balance disorders in a cohort of children with asymptomatic cCMV.METHODS:Comprehensive vestibular, gaze, and balance assessments were performed in 40 children with asymptomatic cCMV. The function of semicircular canals of the inner ear and vestibulo-visual tract were assessed by measuring vestibulo-ocular reflex in a computer-driven motorized rotary chair; inner ear saccular function was assessed by using cervical vestibular evoked myogenic potential; gaze stability during head movement was assessed by using clinical dynamic visual acuity, and balance was assessed by using the sensory organization test and the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition. Test results for each variable were compared with those of a control group without cCMV and/or compared to age-matched normative published data.RESULTS:Vestibular disorders were evident in 45% of the cohort on the basis of rotary chair and cervical vestibular evoked myogenic potential testing, suggesting abnormalities in semicircular canals, the utricle and saccule of the inner ear, and vestibulo-visual tracts. Additionally, 46% of the cohort had difficulties maintaining gaze during head movement, and one-third to one-half of the cohort had difficulties maintaining balance.CONCLUSIONS:Vestibular, gaze, and balance disorders are highly prevalent in children with asymptomatic cCMV. Systematic screening for vestibular disorders will be used to determine the full clinical impact for the development of effective interventions.

Concussion policies are increasingly being developed and adopted among professional sports organizations. We sought to compare the policies of the National Hockey League (NHL), the National Basketball Association (NBA), the National Football League (NFL), and Major League Baseball (MLB). Our objective was to summarize each policy and evaluate the extent to which each policy is organization-specific and/or consistent with medical guidelines. We visited websites for the NHL, NBA, NFL, and MLB. We searched media articles reporting concussion policy. We utilized only publically available data. We collected information on each league's approach to the definition of concussion, education provided about concussion, baseline testing requirements, minimum return to play time and return to play protocol. We found that concussion policies vary across these organizations. Most organizations utilize the Concussion in Sport Group (CISG) definition (2013) to define concussion. The NFL and NBA mandate preseason education. All organizations require some type of baseline testing. All organizations require sideline evaluation after suspected concussion. The NFL and MLB require Sport Concussion Assessment Tool (SCAT) testing for sideline evaluation of suspected concussion. MLB is the only organization to require minimum time before return to play. There is a return to play protocol in place for each organization. The NFL and MLB require independent neurologic consultation as part of their return to play protocol. There is variability in concussion policy among the professional sports organizations. The most pronounced variation from the CISG consensus statement is the variability in the minimum time to return to play. Further, the rules of the individual sports have a role in how concussion policy can be designed and implemented. Professional sports set an example for thousands of recreational sports enthusiasts so their publically available policies on concussion have a large impact.

Three paediatric patients post-mild traumatic brain injury (mTBI, also known as concussion) developed saccadic intrusions, which are irregular, involuntary saccades that interrupt fixation. Each patient presented to a mTBI clinic months post-injury, complaining of headaches, difficulty concentrating, and dizziness. Written informed consent from parents was obtained for use of these cases.

We aimed to describe vestibular/oculomotor function of 7-12-year-old children with CP, Gross Motor Function Classification System (GMFCS) levels (I-III), in comparison to an age-matched control group to understand the effect of the vestibular system on activities and participation of children with CP.Vestibular, oculomotor and balance function were tested in children with CP. Central and peripheral vestibular function was examined using an enclosed rotary chair and infrared video goggles (100 Hz) that measured eye movements. Oculomotor tests included smooth pursuit and optokinetic nystagmus (OKN). Vestibulo-Ocular Reflex (VOR) tests, done in complete darkness, included step rotation (STEP), sinusoidal harmonic acceleration (SHA) test, VOR cancellation and enhancement, and subjective visual vertical and horizontal (SVV/SVH). The integrity of the saccule was tested with the Cervical Vestibular Evoked Myogenic Potential. If able, the participants' balance abilities were examined using the Sensory Organization Test (SOT) to determine ability to maintain standing balance during six conditions that challenged the visual, somatosensory and vestibular systems. Independent t-tests and Mann-Whitney U tests were used to compare results between groups.Forty-one children with CP (mean age = 9.44 years, SD = 1.66; 23F/18M; Gross Motor Function Classification System levels: I (n = 19), II (n = 7), III (n = 15) and thirty-three typically developing (TD) children (mean age = 10.16 years, SD = 1.6; 13F/20M) were recruited from the Birmingham, AL community. There was no significant difference between children with CP and TD children in saccular function (i.e. C-VEMP test), and peripheral vestibular end organ (i.e. SHA test and STEP test), VOR enhancement, or OKN gain. Velocity gain for horizontal smooth pursuit was significantly worse in children with CP (p = 0.009), compared to TD children. Poor mediation of central vestibular function were that evident with significantly higher VOR cancellation gain in children with CP (p 0.0001), compared to TD children and significantly higher SVV variance (p = 0.002), SVH mean (p = 0.001), and SVH variance (p 0.0001) in children with CP compared to TD children. Compromised balance abilities in children with CP was evident with significantly lower composite scores (p 0.0001), vestibular ratio (p 0.0001), and visual ratio (p = 0.021). The somatosensory ratio (p = 0.798) of children with CP was similar to children with TD.Although peripheral vestibular function was intact, children with CP had difficulty coupling eye and head movement (VOR cancellation), using the vestibular system for postural control (SOT), demonstrated poor perception of upright (SVV/SVH), and had difficulty following a slow moving target (smooth pursuit eye movement). These results implicate a central vestibular and oculomotor function impairment the severity of which corresponded with severity of the level of CP.

This study investigates 4 single-nucleotide polymorphisms [Apolipoprotein E (APOE), APOE promoter, catechol-O-methyl transferase (COMT), and dopamine D2 receptor] that have been implicated in concussion susceptibility and/or cognitive ability in collegiate student-athletes.Cross-sectional study.Neuroscience laboratory at Elon University.Two hundred fifty division I collegiate student-athletes (66 women, 184 men) from various sports.All participants completed Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) testing at baseline concussion testing and had a buccal swab taken for DNA for genotyping.Self-reported history of concussions and neurocognitive performance were taken from ImPACT.Individuals carrying an ε4 allele in their APOE gene had a significantly slower reaction time (P = 0.001). Individuals homozygous for the Val allele of the COMT gene showed significantly worse impulse control scores (P = 0.014). None of the genotypes were able to predict self-reported concussion history in collegiate student-athletes.These results indicate that certain genotypes may influence performance on cognitive testing at baseline and that the APOE genotypes may not influence concussion susceptibility as suggested by past studies.

Objective Fatigue and apathy are common symptoms in both multiple sclerosis (MS) and Parkinson's disease (PD). Both symptoms are considered “amotivational”—fatigue is a lack of energy to start or complete an action and apathy is a loss of interest in activities. Whether the two symptoms are related to each other is not known. The present study sought to investigate the prevalence and severity of fatigue and apathy in MS and PD, and the relationship between the two. Methods The Fatigue Severity Scale (FSS) and the Apathy Scale (AS) were administered to 89 consecutive PD and 73 consecutive MS subjects. Results The mean FSS score for PD subjects was 4.46 and 5.01 for MS; the average total AS score for PD was 12.4 and 12.5 for MS. Using a cutoff of >4.0 on the FSS to assess fatigue, 64% of PD subjects and 74% of MS subjects suffered from severe fatigue. Using an AS cutoff score of >14.0 to determine apathy, 57% of PD subjects and 52% of MS subjects were apathetic. There was a significant correlation between FSS score and AS score in both disorders. FSS average scores and AS total scores were significantly correlated with motor severity in PD but not in MS. Duration of disease was not correlated with either scale scores in either disorder. Discussion Results confirm that AS and FSS are correlated with each other in both disorders and that MS subjects rate their fatigue significantly higher.

Background Single-nucleotide polymorphisms (SNPs) of neurologically relevant genes play a role in concussions from increasing susceptibility or hampering cognitive performance. Objective The purpose of this study was to investigate the effects of polymorphisms of APOE, APOE promoter, COMT and DRD2 on baseline neurocognitive function and concussion history in collegiate student-athletes. Design Cross-sectional. Setting Collegiate campus in North Carolina. Participants 262 (194 males, 68 females) collegiate student-athletes. Assessment of risk factors Buccal mucosa swabs were collected from participants. SNP genotyping was run on all samples to determine APOE, APOE promoter, COMT, and DRD2 genotypes. Participants were split into three groups based on their genotypes for each gene. Outcome measures Participants completed the Immediate Post-Concussion Assessment and Cognitive Testing neurocognitive assessment which generated composite scores on Verbal Memory, Visual Memory, Visuomotor Speed, and Reaction Time as well as Impulse Control Results None of the genotype variables influenced number of concussions (p>0.05). MANOVA analysis determined no differences for APOE promoter and DRD2 genotypes (p>0.05). There were statistical differences for APOE for Visuomotor composite (APOE-e3 (m=41.2, %95 CI [40.8, 42.1]) vs e4 (m=39.1, %95 CI [37.8, 40.5], p=0.017) and Reaction Time (APOE-e4 (m=0.62, %95 CI [0.60, 0.64]) was different than both e2 (m=0.57, %95 CI [0.54, 0.60] and e3(m=0.58, %95 CI [0.56, 0.59], p Conclusions APOE and COMT single nucleotide polymorphisms lead to significant differences in neurocognitive performance at baseline but not concussion history. Competing interests None.