Near Point Of Convergence Research Articles

Smartphone Use on Accommodation and Vergence Parameters: A Systematic Review

Introduction: The frequency and the trend of smartphone use increase rapidly, and 85% of Malaysians owns a smartphone and spend an average of 187 minutes per day to use the smartphone. Aims: To evaluate the potential effects of smartphone use on Accommodation and Vergence of the users. Methods: A total of 18 articles were selected in this review following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, and the research question was formulated based on the population, intervention, control, and outcomes (PICO) method. This review was registered with PROSPERO (reference number: CRD42022293325). Data Sources: Databases namely PubMed, Web of Science, and Science-Direct were used in the article search using appropriate keywords, phrases, and Medical Subject Heading (MeSH) terms. The inclusion criteria of this review were journal articles published from January 2010 until December 2021 with full articles or abstract in English available. Results: Accommodative function has been reported to changed significantly with 20 minutes of smartphone use, with reduced amplitude, facility, relative and increased lag. In addition, vergence function has been reported to be altered significantly with receded near point of convergence. Conclusion: Smartphone use has an effect on the accommodation and vergence parameters among adults. Assessments of accommodation and vergence parameters need to be conducted in patients with the symptoms of Computer Vision Syndrome to prevent vision problems. Future reviews are required in younger cohorts with various smartphone features.

The short-term influences of paediatric smartphone use on the eye

The aim of this study is to comprehensively evaluate the effect of smartphone use on the eye. Twenty-two children, aged 8-16 years, participated in this study. A self-administered questionnaire about smartphone usage time, outdoor activities, and sleep time to obtain dry eye was applied to the child and parents. An ocular surface disease index (OSDI), tear break-up time (TBUT), blink time, autorefractometer, optical biometry, accommodation, contrast sensitivity, and optical coherence tomography tests were applied before a 5-min video watching, and during the video session we counted the complete -incomplete blinks. After video watching, we did the tests. After the tests, we again applied a 5-min video watching and after the video we tested all the parameters again, and finally, following a 5-min resting period, we tested the parameters again. We found no difference between the groups in terms of OSDI scores. Children with punctate epithelial erosions and time spent on the phone have a statistical relation. TBUT also differs statistically before and after test periods ( p = .014), since complete blinks did not differ but incomplete blinks differed before and after video watching. The nearpoint of convergence also differs after video watching ( p = .008) and anterior chamber depth (ACD) decreases even after the short-time video watching period. On the contrary, we did not find any effect of short-time smartphone watching on auto-keratometer values and retinal-choroidal thickness. This is the first comprehensive study on the short-term effects of smartphone on the paediatric age group. Even 10 min of smartphone can have an effect on TBUT, incomplete blinks, nearpoint of convergence break-recovery, and ACD. During this coronavirus disease 2019 pandemic, we must be mindful of the time our children spend on the phone and keep in mind that even 10 min can have ocular effects.

Comparing the directional effect of number calling on the developmental eye movement test results in Hebrew‐speaking children

To evaluate the directional effect of number calling on the developmental eye movement (DEM) test in Hebrew-speaking children who read from right (R) to left (L). Previously, the DEM has been studied in nine languages, all read from L to R and has never been tested on Hebrew speakers. Healthy Hebrew-speaking children, aged 6-13 years were divided into two age groups (6-9, 10-13 years). Children had near visual acuity of 0.00 logMAR or better, no strabismus, stereoacuity ≤100 s of arc and near point of convergence ≤6 cm. The DEM test was performed twice, from R to L and L to R, randomly. Comparisons between age groups for horizontal and vertical reading speed and ratio between reading directions were analysed, as well as the correlation between age and directionality. A total of 92 children were included; 48 and 44 in the 6-9 and 10-13 year age groups, respectively. The mean vertical and horizontal time for both directions (R to L and L to R) in the younger group was significantly slower than the older group (p < 0.001). The older children showed no significant difference in the horizontal time reading from L to R and R to L. However, the younger children read more quickly in their native direction (R-L; 71.5 ± 25.9 s) compared with L-R (76.0 ± 31.4 s, p = 0.01). In both directions, the ratio was significantly higher in the younger age group. A negative correlation was demonstrated between age and reading ratio (p = 0.001). A clear directional preference of R to L was found in children under 10 years of age. We suggest administering the test from R to L in young Hebrew-speaking children. These results may also apply to young Arab- and Persian-speaking children who also read from R to L.

Receded near point of convergence as a predictor of mild cognitive impairment in the general geriatric population: results from a population-based study.

To investigate the relationship between near point of convergence (NPC) and mild cognitive impairment (MCI) in the general elderly population. The present report is a part of the Tehran Geriatric Eye Study (TGES): a population-based cross-sectional study conducted on individuals 60 years of age and above living in Tehran, Iran using the multi-stage stratified random cluster sampling method. Cognitive status was assessed using the Persian version of the Mini-Mental State Examination (MMSE). All study participants underwent complete ocular examination including measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, cover testing, NPC measurement, and slit-lamp biomicroscopy. The data of 1190 individuals were analyzed for this report. The mean age of the participants analyzed was 66.82±5.42 (60-92y) and 728 (61.2%) of them were female. Patients with MCI had a significantly more receded NPC compared to subjects with normal cognitive status (10.89±3.58 vs 7.76±2.71 cm, P<0.001). In the multivariable logistic regression model and in the presence of confounding variables, a receded NPC was statistically significantly associated with an increased risk of MCI (odds ratio: 1.334, 95% confidence interval: 1.263 to 1.410, P<0.001). According to receiver operating characteristic (ROC) analysis, a cut point NPC> 8.5 cm (area under the curve: 0.764, P<0.001) could predict the presence of MCI with a sensitivity and specificity of 70.9% and 69.5%, respectively. A receded NPC can be clinically proposed as a predictor of MCI in older adults. It is recommended that elderly with a receded NPC>8.50 cm undergo detailed cognitive screening for a definite diagnosis of MCI. In this case, the necessary interventions can be carried out to slow down MCI progression to dementia.

The effects of breaks on digital eye strain, dry eye and binocular vision: Testing the 20-20-20 rule.

To evaluate the benefits on the eyes of taking breaks based on the 20-20-20 rule. Bespoke computer software using the laptop webcam to assess user breaks, eye gaze and blinking, and emitting personalized reminders of breaks based on the 20-20-20 rule, was downloaded onto the laptops of 29 symptomatic computer users. Digital eye strain (DES), binocular vision and dry eye were assessed before and after two weeks of using the reminders and one week after the discontinuation of the strategy. Binocular measurements included visual acuity, accommodative posture, stereopsis, fixation disparity, ocular alignment, accommodative facility, positive/negative vergences and near point of convergence. Symptoms were evaluated using the computer vision syndrome questionnaire, ocular surface disease index (OSDI), and symptom assessment in dry eye questionnaire (SANDE) versions one and two. Dry eye signs were assessed by measuring tear meniscus height, conjunctival redness, blink rate and incomplete blinking, lipid layer thickness, non-invasive keratograph break-up time, corneal and conjunctival staining and lid wiper epitheliopathy. A decrease in the duration of computer work and the duration of breaks, along with an increase in the number of breaks taken per day was observed as a result of the 20-20-20 rule reminders (p≤0.015). No changes on any binocular parameter were observed after the management period (p≥0.051), except for an increase in accommodative facility (p=0.010). Dry eye symptoms and DES decreased with the rule reminders (p≤0.045), although this improvement was not maintained one week after discontinuation (p>0.05). No changes on any ocular surface and tear film parameter were observed with the rule reminders (p≥0.089). The 20-20-20 rule is an effective strategy for reducing DES and dry eye symptoms, although 2weeks was not enough to considerably improve binocular vision or dry eye signs.

Nexus of ocular motility and dry eye.

To evaluate the effectiveness of vision therapy (VT) in patients with chronic presumed refractory dry eye disease (DED) and concurrent nonstrabismic binocular vision anomalies (NSBVAs). To propose an algorithmic approach to manage patients with refractory DED. Thirty-two patients with chronic (>1 year) presumed refractory DED and NSBVA were prospectively evaluated. The baseline dry eye evaluation and comprehensive orthoptic evaluation were done. VT was administered by a trained orthoptist for 2 weeks. The binocular vision (BV) parameters and percentage subjective improvement were assessed after the VT. On evaluation, 12 patients (37.5%) had both DED and NSBVA, and 20 patients (62.5%) had only NSBVA. Twenty-nine patients (90.62%) showed significant improvement in BV parameters following VT. Binocular near point of accommodation (median, range) improved from 17 (8-40) to 12 (5-26) mm (P value < 0.0001), and near point of convergence (median, range) improved from 6 (3-33) to 6 (5-14) (P value 0.004) with VT. Thirty-one patients (96.87%) reported symptomatic improvement after VT, and 62.5% of these showed more than 50% improvement in symptoms. The present study confirms the beneficial role of VT in the treatment of patients with DED with concurrent NSBVA. It is essential to diagnose and treat NSBVA in patients with DED to ensure complete relief of symptoms and patient satisfaction. As there is a significant overlap between symptoms of dry eye disease and that of NSBVA, a complete orthoptic evaluation is recommended in all patients presenting with refractory dry eye disease related symptoms.

Virtual Reality Application for Vestibular/Ocular Motor Screening: Current Clinical Protocol Versus a Novel Prototype.

Virtual reality (VR) has been explored to improve baseline and postinjury assessments in sport-related concussion (SRC). Some experience symptoms related to VR, unrelated to concussion. This may deter use of vestibular/ocular motor screening (VOMS) using VR. Baseline VR VOMS symptomatology differentiates baseline from overall symptomatology. There will be no difference between current clinical manual VOMS (MAN), a clinical prototype (PRO), and VR for symptom provocation change score (SPCS) and near point of convergence (NPC) average score in a healthy population and sex differences among the 3 modes of administration. Cohort study. Level 3. A total of 688 National Collegiate Athletic Association Division I student-athletes completed VOMS using 3 methods (MAN, N = 111; female athletes, N = 47; male athletes, N = 64; average age, 21 years; PRO, N = 365; female athletes, N = 154; male athletes, N = 211; average age, 21 years; VR, N = 212; female athletes, N = 78; male athletes, N = 134; average age = 20 years) over a 3-year period (2019-2021) during annual baseline testing. Exclusion criteria were as follows: self-reported motion sickness in the past 6 months, existing or previous neurological insult, attention deficit hyperactivity disorder, learning disabilities, or noncorrected vision impairment. Administration of MAN followed the current clinical protocols, PRO used a novel prototype, and VR used an HTC Vive Pro Eye head mounted display. Symptom provocation was compared using Mann-Whitney U tests across each VOMS subtest with total SPCS and NPC average by each method. MAN had significantly (P < 0.01) more baseline SPCS (MAN = 0.466 ± 1.165, PRO = 0.163 ± 0.644, VR = 0.161 ± 0.933) and significantly (P < 0.01) and more SPCS (MAN = 0.396 ± 1.081, PRO = 0.128 ± 0.427, VR = 0.48 ± 0.845) when compared with PRO and VR. NPC average measurements for VR (average, 2.99 ± 0.684 cm) were significantly greater than MAN (average, 2.91 ± 3.35 cm; P < 0.01; Cohen's d = 0.03) and PRO (average, 2.21 ± 1.81 cm; P < 0.01; Cohen's d = 0.57). For sex differences, female athletes reported greater SPCS with PRO (female athletes, 0.29 ± 0.87; male athletes, 0.06 ± 0.29; P < 0.01) but not in VR or MAN. Using a VR system to administer the VOMS may not elicit additional symptoms, resulting in fewer false positives and is somewhat stable between sexes. VOMS may allow for standardization among administrators and reduce possible false positives.

Baseline Computerized Neurocognitive Testing and Oculomotor Measures are not Altered by Hormonal Contraceptive Use.

Neurocognitive testing and oculomotor assessment have been an integral component to provide objective measures for sport-related concussion (SRC) detection and management. Hormonal contraceptive (HC) use is common among collegiate female athletes and may modify baseline SRC performance. The purpose was to examine the effects of HC use on baseline computerized neurocognitive testing (CNT) and oculomotor testing in college-aged individuals. A total of 63 participants (22 HC using females, 22 non-HC using females, 19 males) completed a baseline SRC battery consisting of CNT, near point of convergence (NPC), and the King-Devick (KD) test. CNT measures were composite scores of verbal and visual memory, visual motor processing speed and reaction time, impulse control, and cognitive efficiency index (CEI). NPC was measured as the average convergence distance across three trials. KD time was recorded as total time for each of the two trials and best trial marked as baseline. There were no group differences between HC, non-HC, and male control groups on all baseline CNT composite scores (p = .13-.98), impulse control (p = .47), and CEI (p = .49). NPC distance was similar between groups (p = .41), as well as KD time by trial (Trial 1 p = .65; 2 p = .48) and best time (p = .49). HC use does not appear to influence baseline SRC measures of neurocognition and oculomotor assessment. Clinicians should continue to consider the effects of modifying factors at baseline and post-concussion. Additional research is needed to better understand sex hormone levels and SRC performance measures.

The impact of smartphone use on accommodative functions: pilot study

ABSTRACT Evidence about the effect of smartphone use on accommodation is limited and inconclusive. Several studies have investigated either symptoms or near triad measures following smartphone use. These suggest that, certainly for the short term, smartphones have a negative impact on the near triad and produce symptoms. In addition, there is a body of recent work reporting cases of acute acquired concomitant esotropia (AACE) that may be caused by the accommodation-vergence demand of excessive smartphone use. A pilot study was undertaken to investigate accommodative measures before and after 30 minutes of smartphone use. Participants aged 16-40 years were invited to participate. Accommodative facility (AF), near point of accommodation (NPA), and near point of convergence (NPC) before and after 30 minutes of habitual smartphone use were assessed. NPA and AF were assessed with both eyes open (BEO), right eye (RE) and left eye (LE). Accommodative facility was assessed using ±2DS flipper lenses and measured in cycles per minute (cpm). NPA and NPC were assessed using the RAF rule and measured in centimeters. Data were analyzed in StatsDirect using non-parametric statistical tests. Eighteen participants were recruited, with a mean age of 24 years (SD: 7.6yrs). AF improved by 3cpm (p= .015) for BEO, 2.25cpm for RE (p = .004) and 1.5 cpm for the LE (p =. 278) after smartphone use. NPA with BEO became worse by 2 cm (p =.0474), with the RE worse by 0.5cms (p = .0474) and the LE, worse by 0.125 cms (p = .047). Convergence worsened by 0.75 cms (p = .018). Although these appeared to represent a change in measures following smartphone use, post-hoc analysis with Bonferroni correction demonstrated that these were not statistically significant at the 0.07 significance level. This pilot study found that there was no difference in accommodative and convergence measures before and after 30 minutes of smartphone use. These results suggest evidence contrary to the existing literature. There are several limitations to this pilot study and previous work, which are discussed. Suggestions on future work to explore the effect of smartphone use on the near triad to address limitations and further knowledge, in this area, are provided.

Refractive and Binocular Vision Status and Associated Asthenopia among Clinical Microscopists

Background Clinical microscopists are at a greater risk of developing binocular vision anomalies and asthenopia.&#x0D; Objective To assess the refractive and binocular vision status and to explore the association between the presence of asthenopic symptoms and microscopy work among clinical microscopists working at medical laboratory department.&#x0D; Method This cross-sectional study involved 37 clinical microscopists working at medical laboratory department of Dhulikhel Hospital, Nepal. The study was conducted from January to December 2013. Only those participants who had been using microscope for at least a year were enrolled in this study. Each participant underwent distance visual acuity (VA) assessment, refractions, and orthoptic evaluation, including measurement of distance and near phoria, near point of convergence (NPC), near point of accommodation (NPA), positive fusional vergence (PFV), adduction, and calculation of accommodation convergence/accommodation (AC/A) ratio. The tear test was also carried out in each subject. Information about use of glasses, microscopy work (duration, and time spent per day in microscope), and visual symptoms associated with the use of microscope such as eye strain, headache, double vision, and near vision were collected.&#x0D; Result The mean age of the clinical microscopists was 29 ± 5.7 years. The prevalence of refractive error was 56.76% and the mean spherical equivalent (SE) refractive error was -0.77 ± 0.86 D. Refractive error had neither correlation with microscopy work and asthenopic symptoms associated with it, and nor with binocular vision parameters- NPC, AA and AC/A ratio. However, there was a positive association between asthenopic symptoms and microscopy work. There was statistically significant difference between symptomatic and asymptomatic subjects for binocular vision parameters, including NPC, AA and positive fusional vergence (PFV) for near.&#x0D; Conclusion Microscopy work has an impact on near binocular vision. Asthenopic symptoms bear a positive association with microscopy work. Refractive error has no significant correlation with either microscopy works or associated asthenopic symptoms.

Incidence of Remote Near-Point of Convergence in University Athletes After Sport-Related Concussion.

Near-point of convergence (NPC) testing is an attractive screening tool in the sport setting because it is rapid, requires few resources, and is easy to administer. Remote NPC has been reported after sport-related concussion (SRC), although the incidence among a university-aged population is not well defined. The purpose of the study was to examine the incidence of remote NPC after SRC in a cohort of Canadian interuniversity athletes. Cross-sequential. University. One hundred thirty-two university athletes [SRC, n = 68; musculoskeletal (MSK) injury, n = 64] were tested before the beginning of their competitive season and again after their injury. Healthy athletes measured preseason were compared with athletes after SRC or MSK injury using both longitudinal and cross-sectional designs. Remote NPC (pass/fail), measured at 6 cm or greater, repeated 3 times. After SRC, 22% of athletes failed their test postinjury (95% CI, 14%-33%). Comparatively, in the MSK group, 3% of athletes failed their test postinjury (95% CI, 1%-7%). A direct comparison of both injury groups yielded a mean 19% higher prevalence of failed NPC tests after SRC versus MSK injury (95% CI, 10%-30%). There seems to be no relationship between reported symptom burden and NPC performance after SRC. Remote NPC occurs in approximately 1 of 5 athletes after SRC and is rarely observed after MSK injury.

The Vestibular/Ocular Motor Screening-Child (VOMS-C) tool for concussion evaluation in 5- to 9-year-old pediatric patients: preliminary evidence.

Vestibular and ocular motor dysfunction occurs in an estimated 60%-90% of concussion patients. The Vestibular/Ocular Motor Screening (VOMS) tool is validated for use in concussion patients older than 9 years. The goal of the current study was to adapt the current VOMS tool for a pediatric sample of children aged 5-9 years and establish its clinical utility in this patient population. In this case-control study, 80 symptomatic concussion patients (n = 33 [41%] female) aged 5-9 years (mean age 7.40 ± 1.09 years) and 40 (n = 18 [45%] female) age- and sex-matched uninjured controls (mean age 7.10 ± 1.26 years) completed the VOMS-Child (VOMS-C), a version of the VOMS adapted for younger patients. Differences in binary "yes" or "no" symptom provocation for headache, dizziness, and nausea/"tummy ache" across the 7 items of the VOMS-C, and near point of convergence (NPC) distance, were examined. Logistic regression (LR) models were built to classify concussion and controls. Predicted probabilities were generated from the LR model and entered into receiver operating characteristic (ROC) curve models to generate area under the curve (AUC) values. VOMS-C item provocation ranged from 13% to 30% for concussed patients and 3% to 20% for controls. The LR model distinguished concussed participants from controls (R2 = 0.39; p < 0.001), with significant predictors being smooth pursuits, family depression history, and NPC distance. The ROC analysis had an AUC of 0.81 (95% CI 0.73-0.89; p < 0.001) in the good range. Accurate diagnosis of concussion in the clinic setting requires comprehensive evaluation in multiple domains, including detailed clinical interview, neurocognitive testing, and vestibular/ocular motor assessment, regardless of patient age. Our results provide preliminary support for the VOMS-C as a developmentally appropriate tool for concussion management.

Double Vision and Light Sensitivity Symptoms are Associated With Return-to-School Timing After Pediatric Concussion.

To determine the association between academic time loss postconcussion and vision symptoms/impairments among pediatric patients. Cross-sectional. Sports medicine clinic. Pediatric patients seen for care in a sports medicine clinic between the ages 6 and 18 years (n = 212; mean age = 14.3, SD = 2.4 years; 48% female) were evaluated within 21 days of concussion (mean = 9.8, SD = 5.7 days). Patients were grouped based on academic time loss (missed >5 days vs ≤5 days of school) at their initial postconcussion evaluation. Patients rated concussion symptoms using the Health and Behavior Inventory (HBI) and underwent near point of convergence (NPC) testing. We compared groups on specific HBI symptom ratings of dizziness, blurry vision, seeing double, and light sensitivity, as well as NPC break and recovery point distances. Two hundred twelve patients were included; n = 36 (17%) who reported missing >5 days of school. After adjusting for time since injury, parental education level, mechanism of injury, and preinjury anxiety, patients who reported missing >5 days of school had higher ratings of double vision (β = 0.27; 95% confidence interval [CI], 0.01-0.53; P = 0.04) and light sensitivity (β = 0.506; 95% CI, 0.061-0.951; P = 0.02), but not dizziness (β = 0.390; 95% CI, -0.047 to 0.827; P = 0.08) or blurry vision (β = 0.026; 95% CI, -0.352 to 0.404; P = 0.89). Missing >5 days of school was associated with worse double vision and light sensitivity symptoms. Given the importance of vision in learning, assessing postconcussion vision symptoms may facilitate a successful return to school. Clinicians should assess a wide spectrum of vision-specific symptoms to ensure appropriate support during the return-to-school process.

Vergence/accommodative therapy for symptomatic convergence insufficiency in children: Time course of improvements in convergence function.

To evaluate the time course of improvements in clinical convergence measures for children with symptomatic convergence insufficiency treated with office-based vergence/accommodative therapy. We evaluated convergence measures from 205, 9- to 14-year-old children with symptomatic convergence insufficiency randomised to office-based vergence/accommodative therapy in the Convergence Insufficiency Treatment Trial - Attention and Reading Trial (CITT-ART). Near-point of convergence (NPC) and near-positive fusional vergence (PFV) were measured at baseline and after 4, 8, 12 and 16 weeks of therapy; mean change in NPC and PFV between these time points were compared using repeated measures analysis of variance. Rates of change in NPC and PFV from: (1) baseline to 4 weeks and (2) 4-16 weeks were calculated. For each time point, the proportion of participants to first meet the normal criterion for NPC (<6cm), PFV blur (break if no blur; >15Δ and >2 times the exodeviation) and convergence composite (NPC and PFV both normal) were calculated. The greatest change in NPC and PFV (7.6cm and 12.7 Δ) and the fastest rate of improvement in NPC and PFV (1.9cm/week and 3.2 Δ/week, respectively) were both found during the first 4 weeks of therapy, with both slowing over the subsequent 12 weeks. After 12 weeks of therapy, the NPC, PFV and convergence composite were normal in 93.2%, 91.7% and 87.8% of participants, respectively, and normalised with another 4 weeks of therapy in 4.4%, 2.0% and 4.4% of participants, respectively. Although the greatest improvements in NPC and PFV occurred in the first 4 weeks of therapy, most participants had weekly improvements over the subsequent 12 weeks of treatment. While most children with convergence insufficiency obtained normal convergence following 12 weeks of therapy, an additional 4 weeks of vergence/accommodative therapy may be beneficial for some participants.

Are binocular alignment and convergence amplitude different between phakic and pseudophakic older patients?

ABSTRACT Purpose To compare the binocular alignment status and convergence amplitude between phakic and pseudophakic older adults. Methods The present report is a part of the Tehran Geriatric Eye Study (TGES), a population-based study performed on the elderly population above 60 years of age in Tehran, Iran. All study participants were transferred to the examination site and underwent complete ocular examinations including the measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, unilateral and alternating cover tests, and slit-lamp biomicroscopy. Results Of 3791 invitees, 3310 participated in the TGES (response rate: 87.3%). After applying the exclusion criteria, the data of 1969 individuals were analyzed for this report. The mean of far exophoria, far esophoria, near exophoria, and near esophoria was 5.09 ± 3.66, 8.20 ± 9.60, 6.94 ± 3.69, 7.00 ± 5.83 prism diopter in phakic and 5.15 ± 2.43, 6.50 ± 5.80, 7.77 ± 4.00, 4.75 ± 1.50 prism diopter in pseudophakic individuals, respectively. The mean of far exotropia, far esotropia, near exotropia, and near esotropia was 14.92 ± 9.49, 22.00 ± 13.86, 15.09 ± 7.20, 21.33 ± 14.47 prism diopter in phakic and 19.67 ± 22.5, 8.00 ± 0, 17.36 ± 7.55, 17.36 ± 7.55, 0 prism diopter in pseudophakic individuals, respectively. Near exophoria (P = .003) was significantly higher in pseudophakic than in phakic participants after controlling the effects of age, sex, body mass index, diabetes, and hypertension. The mean near point of convergence was 7.94 ± 3.27 cm in phakic and 7.99 ± 3.3 cm in pseudophakic participants. Conclusion Near exophoria was significantly higher in pseudophakic compared to phakic individuals while other deviations and near point of convergence were not significantly different between phakic and pseudophakic groups.

The Function of the Proprioceptive, Vestibular and Visual Systems Following Fatigue in Individuals With and Without Chronic Ankle Instability.

To maintain postural balance, the proprioceptive, vestibular, and visual systems continuously provide body position and movement data to the central nervous system. In this study, our main aim was to examine, for the first time, the influence of anaerobically or aerobically induced fatigue on these separate functions in persons with and without chronic ankle instability (CAI). We obtained assessments pre- and post-fatigue protocols from 60 physical education students (Mage = 24.3, SD = 3.4) Twenty-seven students had CAI, and 33 students did not have CAI). To measure proprioception, we used the AMEDA device; for vision, we used near point of convergence (NPC); and, for vestibular function, we used subjective visual vertical (SVV). We found a pre-post proprioception (AMEDA) effect in the aerobic group (p < .001), and a visual (NPC) effect in both anaerobic and aerobic participant groups (both p < .001). There were no visual system (NPC) fatigue effect differences among aerobic or anerobic participants who had or did not have CAI (p = .047); there was a significant aerobic fatigue effect on proprioception (AMEDA) (p = .010) that favored participants without CAI. There was a significant interaction effect between time of testing and CAI for visual (NPC) (p = .003) in the aerobic group only. In both the anaerobic and aerobic groups, post-fatigue vestibular function (AMEDA) was significantly lower for those with than those without CAI (anaerobic: p = .030; and aerobic: p =.016). Thus, post-fatigue, participants with CAI showed worse proprioceptive, visual, and vestibular function than those without CAI. Future investigators should further examine each movement sense system in individuals with CAI.

Characterizing the evolution of oculomotor and vestibulo-ocular function over time in children and adolescents after a mild traumatic brain injury.

BackgroundImpairments to oculomotor (OM) and vestibulo-ocular reflex (VOR) function following pediatric mTBI have been demonstrated but are poorly understood. Such impairments can be associated with more negative prognosis, affecting physical and mental wellbeing, emphasizing the need to more fully understand how these evolve.Objectivesto determine i) the extent to which performance on clinical and computerized tests of OM and VOR function varies over time in children and adolescents at 21 days, 3-, and 6-months post-mTBI; ii) the proportion of children and adolescents with mTBI presenting with abnormal scores on these tests at each timepoint.DesignProspective longitudinal design.SettingTertiary care pediatric hospital.Participants36 participants with mTBI aged 6 to18.ProceduresParticipants were assessed on a battery of OM and VOR tests within 21 days, at 3- and 6-months post injury.Outcome measuresClinical measures: Vestibular/ocular motor screening tool (VOMS) (symptom provocation and performance); Computerized measures: reflexive saccade test (response latency), video head impulse test (VOR gain), and dynamic visual acuity test (LogMAR change).AnalysisGeneralized estimating equations (parameter estimates and odd ratios) estimated the effect of time. Proportions above and below normal cut-off values were determined.ResultsOur sample consisted of 52.8% females [mean age 13.98 (2.4) years, assessed on average 19.07 (8–33) days post-injury]. Older children performed better on visual motion sensitivity (OR 1.43, p = 0.03) and female participants worse on near point of convergence (OR 0.19, p = 0.03). Change over time (toward recovery) was demonstrated by VOMS overall symptom provocation (OR 9.90, p = 0.012), vertical smooth pursuit (OR 4.04, p = 0.03), voluntary saccade performance (OR 6.06, p = 0.005) and right VOR gain (0.068, p = 0.013). Version performance and VOR symptom provocation showed high abnormal proportions at initial assessment.DiscussionResults indicate impairments to the VOR pathway may be present and driving symptom provocation. Vertical smooth pursuit and saccade findings underline the need to include these tasks in test batteries to comprehensively assess the integrity of OM and vestibular systems post-mTBI.ImplicationsFindings demonstrate 1) added value in including symptom and performance-based measures in when OM and VOR assessments; 2) the relative stability of constructs measured beyond 3 months post mTBI.

Evaluation of the vestibular/ocular motor screening assessment in active combat sport athletes: an exploratory study

ABSTRACT Objective The first aim of this study was to compare the results of the vestibular/ocular motor screening (VOMS) in combat sport athletes with a healthy control population. Second, to explore differences between athletes with and without a concussion history. Third, to examine the relationship between VOMS and the Post-Concussion Symptom Scale (PCSS) in combat sport athletes. Participants Forty active male combat sport athletes and 40 healthy male control participants were recruited from 4 clubs and a University in Australia. Methods Participants completed the VOMS in a primary care physiotherapy clinic. Participants completed an injury questionnaire and the PCSS. Results An “abnormal” score in at least one subtest or near point convergence (NPC) was recorded in 45% of the combat group compared with 22.5% of the control group. All VOMS scores and NPC distance were greater in the combat group compared with control group (p < 0.05). The VOMS scores were found to be moderately positively correlated with the PCSS. There was no difference in VOMS between athletes with and without a history of concussion (p > 0.05). Conclusion VOMS scores differed between combat sport athletes and control participants. The PCSS may aid clinicians in identifying athletes who have underlying vestibular/oculomotor impairment.

Dizziness Is Associated With Neck/Shoulder Pain Following Pediatric Concussion.

To examine the association between dizziness and neck/shoulder pain after concussion and if differences in postural stability and oculomotor function exist among patients reporting dizziness with or without concurrent neck/shoulder pain. Cross sectional. Sports medicine clinic. Pediatric patients ≤14 days post concussion. N/A. Patients completed the Health and Behavior Inventory (HBI) symptom rating and separately rated neck/shoulder pain (scale 0-3; 0 = no pain). We grouped patients by HBI dizziness rating (0 = not-dizzy; 1-3 = dizzy) and compared neck/shoulder pain ratings between the groups. We then compared oculomotor and postural stability outcomes between dizzy patients with and without neck/shoulder pain. We included 153 patients: dizzy (n = 100; age = 14.6 ± 2.2 years; 48% female) and not-dizzy (n = 53, age = 14.4 ± 3.1 years; 38% female). The dizzy group reported significantly higher neck/shoulder pain (1.4 ± 1.1 vs 0.5 ± 0.9 points, P < 0.001) and total symptom score (25.7 ± 11.2 vs 11.7 ± 9.3 points, P < 0.001) than the not-dizzy group. After adjusting for total symptom score and preinjury anxiety, depression, and migraines, dizziness was associated with higher odds of neck/shoulder pain (odds ratio = 1.9, 95% CI, 1.2-3.0; P = 0.004). No differences were observed between dizzy patients with and without neck/shoulder pain for near point of convergence (10.0 ± 7.5 vs 8.5 ± 6.7 cm, P = 0.43), modified Balance Error Scoring System (8.9 ± 5.5 vs 6.8 ± 4.7 errors, P = 0.09), or tandem gait (single-task: 26.0 ± 12.3 vs 24.2 ± 11.9 seconds, P = 0.56; dual-task: 35.1 ± 14.3 vs 35.6 ± 18.6 seconds, P = 0.90). In concussion patients experiencing dizziness, evaluating neck/shoulder pain may help identify individuals who would benefit from cervical spine rehabilitation. However, other potential causes of dizziness should also be evaluated to facilitate timely recovery.

Changes to Visual Parameters Following Virtual Reality Gameplay.

Introduction:Virtual reality (VR) gameplay is popular with a range of games and educational resources available. However, it puts high demands on the visual system. Current evidence shows conflicting impacts on visual parameters. Therefore, this study explores the changes to vision following VR gameplay.Methods:The study was conducted at the School of Health Sciences, University of Liverpool. All participants had binocular vision with good visual acuity and no manifest strabismus. Participants were assessed before and after playing 15 minutes of the VR game Beat Saber, which incorporated convergence and divergence movements. Clinical assessments including near point of convergence (NPC) and near point of accommodation (NPA) using the RAF rule; accommodative convergence to accommodation (AC/A) ratio; motor fusion using the prism fusion range (at 33cm), accommodation facility using +2.00/–2.00DS flipper lenses, and stereoacuity using the Frisby stereo test were assessed before and after playing.Results:Seventy-eight participants (19–25 years old) were included in the study, with 16 males and 41 females respectively. The breakpoint of convergence reduced by 0.5 cm (p = 0.001). The binocular accommodative facility improved by 2 cycles per minute (cpm); p = 0.004. The mean, near horizontal prism fusion range (PFR) base break and recovery points both worsened by of 5.0 dioptres (p = 0.003), whereas the mean near horizontal PFR base in recovery point improved by of 4.0 dioptres (p = 0.003).Discussion:The study validated previous findings as VR gameplay over-exercised and fatigued convergence muscles, but to a small degree. The VR experience improved the participants’ ability to change focus quickly and improve accommodation, as well as the divergence function of the eye. However, as the participants were retested directly after the VR gameplay, the findings were limited to short term effects on vision.