Near Point Of Convergence Research Articles

A Novel Device for Vergence Exercises: Testing Automatic Dual Rotational Risley Prisms on Asymptomatic Adults and Patients with Convergence Insufficiency.

This study investigated the effects of automatic dual rotational Risley prisms (ADRRPs), a mobile phone application-operated device, on vergence abilities in young adults. Fifty-six participants aged 20-24 performed vergence exercises. The test group used prisms with power changes from 30Δ base-out to 10Δ base-in, while the control group used plano lenses for 10min. Ophthalmic examinations included lateral heterophoria, near point of convergence (NPC), vergence facility (VF), negative fusional vergence (NFV), and positive fusional vergence (PFV), all measured before and after the vergence exercises. Pre- and post-test results were analyzed using a paired sample ttest. Additionally, three cases with convergence insufficiency (CI) performed similar exercises for 12weeks. Participants were divided into the test group (n = 39; age 21.82 ± 1.10years) and control group (n = 17; age 20.53 ± 0.51years). In the test group, NPC improved from 6.11 ± 2.52cm to 5.77 ± 2.30cm (p = 0.023). VF increased from 13.75 ± 4.10cpm to 16.50 ± 4.42cpm (p = 0.007). PFV at 6m and 0.4m increased from 19.49 ± 6.77∆ to 22.19 ± 6.64∆ (p < 0.001) and 20.51 ± 7.05∆ to 22.69 ± 6.44∆ (p = 0.012), respectively. After 12weeks, convergence insufficiency symptom survey scores for cases with CI decreased significantly, with NPC improving from 7.0 to 0cm, 6.0 to 5.8cm, and 6.0 to 4.7cm. PFV increased from 10 to 25∆, 20 to 30∆, and 25 to 50∆. This preliminary study showed the effect of ADRRPs on improving vergence abilities. Further studies are needed to investigate the long-term sustainability and effects in a larger population of individuals with CI of this approach.

Convergence insufficiency prevalence in attention deficit and hyperactivity disorder children depends on the diagnosis criteria.

Attention deficit and hyperactivity disorder (ADHD) is a neurodevelopmental condition commonly seen in children and adolescents, characterised by an increase in distractibility or inattention. Several studies have noted a higher rate of visual problems in this group, especially convergence insufficiency (CI), but when using different diagnostic criteria. The aim of this study was to evaluate visual function in ADHD children and non-ADHD controls to compare the different signs for diagnosis of CI. In this prospective case-control study, a group of children aged 7-17 years, diagnosed with ADHD before the start of pharmacological treatment and matched for age and gender with non-ADHD controls were examined. Visual acuity (VA), objective and subjective refraction, accommodative amplitude and facility, heterophoria, positive and negative fusional vergences (PFV and NFV) and stereopsis were assessed. Sixty participants (30 ADHD and 30 non-ADHD controls) were evaluated. There was no significant difference between the two groups for VA, refraction and accommodative abilities. There were significant differences in PFV and NFV: PFV break/recovery values for the ADHD and control groups were 18.9/16.2∆ and 26.9/22.1∆, respectively. Respective values for NFV were 15.7/13∆ and 19.3/15.9∆. Using the three signs of receded near point of convergence (NPC), decreased PFV and exophoria 4∆ greater at near than distance, the prevalence of CI was equivalent for the ADHD and controls (p = 0.34) If only two signs were considered for the CI diagnosis, (i.e., receded NPC and decreased PFV), then prevalence was significantly greater for the ADHD group (p < 0.01). These results show a higher prevalence of binocular vision problems in the ADHD group. This suggests a relationship between vergence problems and ADHD, but the direction of this link remains unclear. Further studies with specific samples may be needed to understand fully the association between binocular vision disorders and ADHD.

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

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

One-year follow-up of clinical convergence measures in children enrolled in the Convergence Insufficiency Treatment Trial-Attention and Reading Trial.

To assess the long-term stability of clinical measures of convergence (near point of convergence [NPC] and positive fusional vergence [PFV]) in participants enrolled in the Convergence Insufficiency Treatment Trial-Attention and Reading Trial (CITT-ART) who received 16 weeks of office-based vergence/accommodative therapy. A total of 310 children, 9-14 years old, with symptomatic convergence insufficiency were enrolled in CITT-ART. Some 270 completed both their 16-week primary outcome visit followed by a 1-year follow-up visit. Of those 270, 181 (67%) were randomised to the vergence/accommodative therapy. Of the 181 in the vergence/accommodative group, 121 (67%) reported not receiving any additional treatment after the 16-week primary outcome visit. The mean change in NPC, PFV and percentages of children classified by the predetermined success criteria of convergence (normal NPC [<6 cm] and/or improved by ≥4 cm; normal PFV [passing Sheard's criterion and base-out break >15Δ] and/or improved by ≥10Δ) were compared at the 16-week primary outcome visit and 1 year later. Of the 121 who returned for their 1-year follow-up visit, there was no significant change in mean adjusted NPC (reduction of -0.2 cm; 95% CI: -1.0 to 0.5 cm) at 1 year. There was a statistically significant decrease in mean-adjusted PFV (-4.7∆; 95% CI: -6.5 to -2.8Δ) at 1 year. There were similar percentages of participants classified as 'normal' (p = 0.30), 'normal and/or improved' (p > 0.50) and 'normal and improved' (p > 0.14) based on NPC and PFV at the 1-year visit compared with the 16-week primary outcome visit. The improvements in NPC and PFV following 16 weeks of vergence/accommodative therapy (with no reported additional treatment thereafter) in children with symptomatic convergence insufficiency persisted 1-year post-treatment.

Association of Accommodation and Convergence with Axial Length Elongation in Children with Basic Intermittent Exotropia: A 12-Month Observational Study.

The aim of the study was to investigate the association of parameters related to accommodation and convergence and axial elongation in basic intermittent exotropia (IXT) patients and the potential clinical predictors of axial length (AL) growth. A total of 140 basic IXT patients were recruited in this study. The medians of AL growth in different age brackets were chosen to divide the subjects into group A (slower axial elongation group, n = 69) and group B (faster axial elongation group, n = 71). Parameters of dominant and nondominant eyes were compared and analyzed during the 12-month follow-up period. The parameters, including baseline refraction, angle of deviation, Newcastle control score (NCS), accommodative amplitude (AMP), accommodative facility (AMF), accommodative response, positive or negative relative accommodation (PRA/NRA), and near point of convergence (NPC), were analyzed via univariate and multivariate regression. Subjects in the faster axial elongation group tended to have more myopic spherical equivalents (t = 3.956, p &lt; 0.001), greater AMPs of dominant eyes (t = -2.238, p = 0.027), and fewer near points of convergence (t = 2.347, p = 0.020) than in the slower axial elongation group. For dominant eyes, logistic and linear regression analysis revealed that more negative spherical equivalents (OR = 0.603, p &lt; 0.001; β = -0.045, p &lt; 0.001), greater AMPs (OR = 1.201, p = 0.027; β = 0.023, p = 0.010), and less near points of convergence (OR = 0.883, p = 0.021; β = -0.012, p = 0.019) were correlated with the faster axial elongation. For nondominant eyes, a more myopic spherical equivalent (OR = 0.682; p = 0.001; β = -0.029, p = 0.005) was the only parameter correlated with faster axial elongation through regression analysis. In children with basic IXT, faster axial elongation in the dominant eyes was associated with more myopic spherical equivalents, greater AMPs, and lower NPCs. These accommodative parameters can serve as potential clinical indicators for monitoring myopia progression in addition to AL.

The Impact of Optimized Blinking on Vision and Related Parameters in Individuals With Computer Vision Syndrome: A Single-Blind Randomized Controlled Trial.

Computer vision syndrome (CVS) has become a significant issue for individuals working on computers and digital devices for extended periods. The ocular and periocular symptoms and signs associated with CVS are a major concern, affecting individuals physically and financially. Additionally, CVS has been linked to the rapid progression of myopia, exacerbating the situation. Blinking has been one of the major treatment methods for the treatment of CVS. This study presents a unique and novel randomized controlled therapeutic trial that evaluates the impact of extended blinking therapyon eyehealth and vision, along with other related parameters. Materialsandmethods: The present studyis a randomized controlled trial conducted from September 2022 to April 2024. Participants aged 18-40 with CVSand a computer vision syndrome questionnaire (CVS-Q)score of ≥6, with mild to moderate refractive error (between -6D and +4D), were included. The sample size was determined based on a pilot study, resulting in a minimum required sample size of 36 patients (18 cases and 18 controls). Participants were randomly assigned to either the case (interventional) or control (conventional) group and were followed up for six months. Cases received conventional CVS treatment plus optimized blinking exercises, while controls received conventional therapy only. Comprehensive ocular assessments were conducted bi-monthly over six months, evaluating changes in uncorrected visual acuity (UCVA), refractive error, near point of accommodation (NPA), near point of convergence (NPC), Schirmer's test, and tear film breakup time (TBUT). The study included 20 patients in the case group and 18 in the control group, primarily aged 20-29 (60.5%). Most patients used laptops for their activities (55.26%). The CVS-Q score significantly decreased in both groups following treatment, with both cases and controls showing significant improvement (p<0.001 for both groups). UCVA in the right eye (RE) and left eye (LE) of the cases improved significantly post-treatment in the interventional group (RE: p=0.002; LE: p<0.001). A significant change in refractive error, which is measured as spherical equivalent (SE), was seen among cases following treatment (RE: p<0.001; LE: p=0.021). Controls showed no significant changes in visual acuity or refractive error. The NPAin the cases improved significantly in the RE (p=0.027) but not in the left. The NPC in the intervention group showed no significant change, while controls showed considerable improvement (p=0.042). Schirmer's test results showed no significant change in either group. However, TBUTin the cases improved significantly (RE: p<0.001; LE: p<0.001). In the controls, TBUT decreased significantly, indicating a deterioration in tear film stability. Asthenopia grades improved considerably in cases, while controls showed only some improvement. Severe symptoms still remained in the control group, emphasizing the potential benefits of the blinking exercise in reducing asthenopia symptoms. Optimized blinking therapy significantly improves vision and refractive error, tear film stability, and discomfort, making it beneficial for chronic computer users to maintain ocular health and enhance productivity and quality of life.

From convergence insufficiency to functional reorganization: Alongitudinal randomized controlled trial of treatment-induced connectivity plasticity.

Convergence Insufficiency (CI) is the most prevalent oculomotor dysfunction of binocular vision that negatively impacts quality of life when performing visual near tasks. Decreased resting-state functional connectivity (RSFC) is reported in the CI participants compared to binocularly normal control participants. Studies report that therapeutic interventions such as office-based vergence and accommodative therapy (OBVAT) can improve CI participants' clinical signs, visual symptoms, and task-related functional activity. However, longitudinal studies investigating the RSFC changes after such treatments in participants with CI have not been conducted. This study aimed to investigate the neural basis of OBVAT using RSFC in CI participants compared to the placebo treatment to understand how OBVAT improves visual function and symptoms. A total of 51 CI participants between 18 and 35 years of age were included in the study and randomly allocated to receive either 12 one-hour sessions of OBVAT or placebo treatment for 6 to 8 weeks (1 to 2 sessions per week). Resting-state functional magnetic resonance imaging and clinical assessments were evaluated at baseline and outcome for each treatment group. Region of interest (ROI) analysis was conducted in nine ROIs of the oculomotor vergence network, including the following: cerebellar vermis (CV), frontal eye fields (FEF), supplementary eye fields (SEF), parietal eye fields (PEF), and primary visual cortices (V1). Paired t-tests assessed RSFC changes in each group. A linear regression analysis was conducted for significant ROI pairs in the group-level analysis for correlations with clinical measures. Paired t-test results showed increased RSFC in 10 ROI pairs after the OBVAT but not placebo treatment (p < 0.05, false discovery rate corrected). These ROI pairs included the following: Left (L)-SEF-Right (R)-V1, L-SEF-CV, R-SEF-R-PEF, R-SEF-L-V1, R-SEF-R-V1, R-SEF-CV, R-PEF-CV, L-V1-CV, R-V1-CV, and L-V1-R-V1. Significant correlations were observed between the RSFC strength of the R-SEF-R-PEF ROI pair and the following clinical visual function parameters: positive fusional vergence and near point of convergence (p < 0.05). OBVAT, but not placebo treatment, increased the RSFC in the ROIs of the oculomotor vergence network, which was correlated with the improvements in the clinical measures of the CI participants.

Association of smartphones use, ocular symptoms and binocular dysfunctions in adolescents: a hospital-based cross-sectional study

ABSTRACT Purpose Given the current scenario of increased smartphone use in youth, this study aims to evaluate the proportion of ocular symptoms and binocular dysfunction and their association with smartphone use in adolescents through a hospital-based cross-sectional study. Methods The participants were asked to fill out questionnaires related to smartphone use and symptoms of eyestrain experienced (Balik et al. and Kucer). They were asked about the following seven symptoms: blurring of vision, redness, visual disturbance, secretion, inflammation, lacrimation, and dryness. Each symptom out of the 7, was scored on a scale of 0–1 and was used to calculate an Ocular Symptom Score (OSS) by summing the scores of each symptom.Depending upon the duration of smartphone usage, the participants were classified into four groups: <2 hours/day, 2–4 hours/day, 4–6 hours/day, and >6 hours/day. Binocular functions were assessed using near point of convergence (NPC), near point of accommodation (NPA), Accommodative convergence/Accommodation (AC/A) ratio, dissociated heterophoria, and binocular accommodative facility (BAF). Results A total of 123 smartphone user adolescents, aged 10–19 years were included in this study. The mean age of the study population was 16.58 + 2.8 years, out of which 52.03% were males. Prevalence of ocular symptoms was higher in groups with greater duration of smartphone use (2 to 4, 4 to 6, and >6 hours/day as compared to <2 hours/day: 90.48%, 94.74%, 100% vs. 75% respectively). The mean of NPC was 8.51, it was highest in subjects using smartphones for >6 hours. (p-value = .001). The mean AC/A ratio was 2.83 + 1.03: 1. A low AC/A ratio was associated with a longer duration of smartphone usage (p-value = .0001). The mean of BAF was 7.4 + 3.18 cycles/min, only 30 (24.4%) participants had BAF beyond the normal range (<5 cycles/min). The mean of BAF was lowest in the group with >6 hours/day of smartphone use (p-value < .0001). No significant change was found in NPA and dissociated heterophoria with the duration of smartphone usage. Conclusion Higher duration of smartphone use (>2 hours/day) is associated with various ocular symptoms and binocular dysfunction. However, additional research is necessary to authenticate the results of the study.

Evaluation of near point of convergence and amplitude of accommodation after treatment of malaria with artemether-lumefantrine

Evaluation of near point of convergence and amplitude of accommodation after treatment of malaria with artemether-lumefantrine

OculoMotor & Vestibular Endurance Screening (MoVES) Normative, Repeatability, and Reliability Data.

This study aims to assess oculomotor and vestibular endurance by utilizing the Oculomotor and Vestibular Endurance Screening (MoVES) assessment in athletes' pre-season and post-season and after a suspected head injury to detect impairment. Athletes (N = 311, 19.4 ± 1.3 years) were recruited to perform the following seven tasks: (1) horizontal saccades, (2) vertical saccades, (3) vergence jumps, (4) horizontal vestibular-oculomotor reflex (VOR), (5) vertical VOR, (6) amplitude of accommodation (AoA), and (7) near point of convergence (NPC). At pre-season, the observed number of eye movements in 60 s are horizontal saccades (74 ± 13 initial 30 s; 67 ± 11 latter 30 s), vertical saccades (70 ± 13; 66 ± 10), vergence jumps (48 ± 12; 45 ± 13), horizontal VOR (38 ± 11; 38 ± 11), and vertical VOR (8 ± 11; 38 ± 11). These results establish a normative database for eye movements within the MoVES assessment and show consistency in the number of movements from pre-season to post-season. The initial results show a trending decrease in the number of eye movements in the initial days post-head injury, which improves to pre-season measures 14-21 days post-injury. This foundation can be used by future studies to explore the extent of binocular and vestibular endurance dysfunctions caused by head injuries that subside within two weeks.

Immediate Effects of Pencil Push-Up Exercise on Visual Accommodation Skills in Amateur Badminton Players: A Randomized Controlled Trial

Background Visual skills are crucial for peak athletic performance, with Visual Accommodation (VA) playing a vital role. However, the immediate effects of interventions on VA in sports remain unclear. Objective To investigate the acute effects of a 10-minute Pencil Push-Up (PPU) exercise on VA skills in amateur badminton players. Methods A two-arm, parallel, randomized controlled trial was conducted with twenty-eight amateur badminton players. Participants were matched by age, duration, and frequency of badminton practice, as well as visual health, and randomly assigned to either a Trained Group (TG) or an untrained group (NT). The TG performed a 10-minute PPU exercise, while the NT rested with closed eyes for the same duration. VA parameters, including Amplitude of Accommodation (AA), Accommodative Facility (AF), and Near Point of Convergence (NPC), were assessed before and after the intervention. Results Significant improvements in AA and AF were observed in the TG from pre- to post-intervention (AA: p &lt; .0001, Cohen's d = 1.68; AF: p &lt; .0001, Cohen's d = 3.10). However, no significant changes were observed in NPC (p= .45, Cohen's d =0.60). Furthermore, the TG exhibited greater improvements in AA and AF compared to the NT at post-intervention (AA: 95%CI= [-2.812 to -0.2314], p = .02; AF: 95%CI= [-8.363 to -3.680], p &lt; .0001). No changes were observed in the NT group. Conclusion A single session of pencil push-up exercise acutely enhanced visual accommodation skills, specifically amplitude of accommodation and accommodative facility, in amateur badminton players. This suggests that visual accommodation training methods like pencil push-ups could improve visual performance in sports. Clinical Trials Registry TCTR20240531002 (https://www.thaiclinicaltrials.org/show/TCTR20240531002).

Comparative Effectiveness of different therapies for Convergence Insufficiency

Purpose: This study aimed to determine the effectiveness of different treatment options such as brock string, dot card, jump convergence and pencil push-up exercises for convergence insufficiency (CI). Methodology: After ethical approval, this quasi experimental study was conducted at District Head Quarter (DHQ) Bhakkar, Thel University Bhakkar, schools and collages of Bhakkar and district Layyah by selecting 140 patients presenting with symptomatic convergence insufficiency through non-probability convenient sampling. After informed consent, Positive Fusional Vergence (PFV), CI Symptom Survey (CISS) and near point of convergence (NPC) were measured. Then randomly divide into four groups of 35 patients by non-probability purposive sampling. Each group received one of the chosen therapy for 3 consecutive months. All patients were examined and self-structure proforma was filled as baseline data on each follow-up of therapy. Data was analyzed by IBM SPSS version 23. Results: After completion of three month of treatment, near point of convergence improved from mean 13.343 ±.219 to 8.757±.194; CI 95%: p&lt;0.001 respectively in brock string, mean 13.486 ±.197 to 7.729 ±.169; CI 95%: p&lt;0.001 in dot card exercise, in jump convergence mean 13.614 ±.214 to 9.057, ±.170; CI 95%: p&lt;0.001 improvement of NPC occur and in pencil push-up 13.243 ±.208 to 8.329 ±.143; CI 95%: p&lt;0.001. Conclusion: The dot card is most effective treatment to perform at home for CI, effective for achieving clinically significant improvements in signs and symptoms associated with CI in young adults.

Vergence and accommodation deficits in paediatric and adolescent patients during sub-acute and chronic phases of concussion recovery.

Visual function deficits have been reported in adolescents following concussion. We compared vergence and accommodation deficits in paediatric and adolescent patients at a tertiary medical centre in the sub-acute (15 days to 12 weeks) and chronic (12 weeks to 1 year) phases of concussion recovery. The study included patients aged 7 to <18 years seen between 2014 and 2021, who had a binocular vision (BV) examination conducted within 15 days and 1 year of their concussion injury. Included patients had to have 0.10 logMAR monocular best-corrected vision or better in both eyes and be wearing a habitual refractive correction. BV examinations at near included measurements of near point of convergence, convergence and divergence amplitudes, vergence facility, monocular accommodative amplitude and monocular accommodative facility. Vergence and accommodation deficits were diagnosed using established clinical criteria. Group differences were assessed using nonparametric statistics and ANCOVA modelling. A total of 259 patients were included with 111 in the sub-acute phase and 148 in the chronic phase of concussion recovery. There was no significant difference in the rates of vergence deficits between the two phases of concussion recovery (sub-acute = 48.6%; chronic = 49.3%). There was also no significant difference in the rates of accommodation deficits between the two phases of concussion recovery (sub-acute = 82.0%; chronic = 77.0%). Patients in both the sub-acute and chronic phases of concussion recovery exhibited a high frequency of vergence and accommodation deficits, with no significant differences between groups. Results indicate that patients exhibiting vision deficits in the sub-acute phase may not resolve without intervention, though a prospective, longitudinal study is required to test the hypothesis.

Comparing clinical measures of near point of convergence and accommodation from the lateral canthus and browline in a paediatric and adolescent population.

Clinicians measure the near point of convergence (NPC) and the amplitude of accommodation (AA) from the spectacle plane, the bridge of the nose or the lateral canthus when assessing visual function. These values are compared to standard clinical criteria to diagnose vergence and accommodation deficits, despite varying reference points. This prospective study explored measuring relative to the spectacle plane and from the lateral canthus for NPC and monocular AA, and the resulting clinical implications of diagnosing visual deficits. Participants were seen by a single clinician for an eye examination. NPC was measured from the forehead and the lateral canthus of the right eye. Monocular AA was measured from the brow and the lateral canthus. Differences between measurements were analysed using non-parametric statistical tests including Wilcoxon Signed Rank, as well as linear regression and a linear mixed effects model to adjust for inter-eye correlation and repeated measures. Chi-square tests were used to assess differences in rates of abnormal findings. Data were collected from 70 participants (53% female, median age 13 [11-15] years). On average, measuring NPC from the lateral canthus yielded a value 1.8 cm higher than measuring from the forehead. Measuring AA from the lateral canthus resulted in an average difference of 1.5 cm compared to measuring from the brow. A total of 39% and 76% of subjects failed NPC compared to clinical norms when measured from the forehead or the lateral canthus, respectively, while 7% and 40% failed AA when measured from the brow or the lateral canthus, respectively. With the variable anatomy of the eye, it is imperative to account for the measurement point when assessing visual function. Measuring from the lateral canthus greatly increased the failure rates for NPC and AA compared with measuring from the forehead and brow, respectively.

Assessing Brain Processing Deficits Using Neuropsychological and Vision-Specific Tests for Concussion.

Since verbal memory and visual processing transpire within analogous cerebral regions, this study assessed (i) if a visual function can predict verbal memory performance. It also hypothesized whether neurocognitive (e.g., ImPACT) tests focusing on the Visual Memory and Cognitive Efficacy Index will predict Verbal Memory scores and (ii) if vision metrics and age can identify individuals with a history of concussion. Finally, it also hypothesized that King-Devick and near point of convergence scores alongside age considerations will identify candidates with a prior reported history of concussion. This observational cohort assessed 25 collegiate ice hockey players prior to the competitive season considering age (19.76 ± 1.42 years) and BMI (25.9 ± 3.0 kg/cm2). Hypothesis 1 was assessed using a hierarchical (sequential) multiple regression analysis, assessing the predictive capacity of Visual Memory and Cognitive Efficacy Index scores in relation to Verbal Memory scores. Hypothesis 2 utilized a binomial logistic regression to determine if King-Devick and near point of convergence scores predict those with a prior history of concussion. Hypothesis 1 developed two models, where Model 1 included Visual Memory as the predictor, while Model 2 added the Cognitive Efficacy Index as a predictor for verbal memory scores. Model 1 significantly explained 41% of the variance. Results from Model 2 suggest that the Cognitive Efficacy Index explained an additional 24.4%. Thus, Model 2 was interpreted where only the Cognitive Efficacy Index was a significant predictor (p = 0.001). For every 1 unit increase in the Cognitive Efficacy Index, Verbal Memory increased by 41.16. Hypothesis 2's model was significant, accounting for 37.9% of the variance in those with a history of concussion. However, there were no significant unique predictors within the model as age (Wald = 1.26, p = 0.261), King-Devick (Wald = 2.31, p = 0.128), and near point of convergence (Wald = 2.43, p = 0.119) were not significant predictors individually. The conflicting findings of this study indicate that baseline data for those with a history of concussion greater than one year may not be comparable to the same metrics during acute concussion episodes. Young athletes who sustain a concussion may be able to overcompensate via the visual system. Future prospective studies with larger sample sizes are required using the proposed model's objective metrics.

Evaluation of convergence, accommodation and fusional vergence in pre-presbyopes with asthenopia

Background: Pre-presbyopes may suffer from ocular symptoms such as asthenopia of near work.Aim: This study aimed to evaluate near points of convergence, amplitudes of accommodation, and fusional vergence among pre-presbyopes with asthenopia symptoms.Setting: The study was conducted at El-Walidain Eye Hospital, Khartoum, Sudan in 2022.Methods: The study was a hospital-based prospective, including 107 pre-presbyopes aged 35–40 years who complained of asthenopia symptoms. Clinical examinations included an assessment of amplitude of accommodation, near point of convergence and fusional vergence.Results: The findings showed receded in near points of convergence and a decrease in the accommodation was highly significantly associated with increased age among emerging presbyopes with asthenopia symptoms (p = 0.0001). Conversely, positive and negative fusional vergence amplitudes were not significantly correlated with age with p = 0.109 and p = 0.355, respectively. Positive and negative fusional amplitudes were not significantly different between males and females (p ˃ 0.05). Esophoria was more common in pre-presbyopia 62 (57.4%) and exophoria 45 (43.6) with p = 0.503.Conclusion: The pre-presbyopes presented with low accommodation amplitude and receded near point of convergence, but without significant changes in positive and negative fusional vergence amplitudes.Contribution: This study added by demonstrating how early presbyopia altered accommodation amplitude and near point of convergence significantly while having no significant impact on amplitudes of positive and negative fusional vergence.

Convergence insufficiency in patients with post-concussion syndrome is accompanied by a higher symptom load: a cross-sectional study

ABSTRACT Objective To estimate the prevalence of convergence insufficiency (CI) in adult patients with post-concussion syndrome and determine the impact of CI on symptom load. Methods Cross-sectional study of 103 patients with neurological symptoms 2–6 months after a concussion. Symptoms were assessed with the Rivermead Post Concussion Symptoms Questionnaire (RPQ), and CI was diagnosed using near point of convergence, vergence facility, and the Convergence Insufficiency Symptom Survey. The RPQ score for patients with and without CI was compared, and sensitivity, specificity, and area under the receiver operating characteristic curve for the two visually related RPQ questions as indicators of CI were calculated. Results The proportion of patients diagnosed with symptomatic CI was 20.4% (95% confidence interval: 13.1–29.5%). The RPQ score was significantly higher for patients with symptomatic CI both before (p = .01) and after removal of the two visually related questions in the RPQ-questionnaire (p = .03). The two visually related RPQ questions were unable to detect CI. Conclusion In patients with post-concussion syndrome, the load of nonvisual symptoms is higher in the presence of CI. A prospective interventional study on CI is required to study the relationship between CI and other post-concussion symptoms.

Pilot Study Assessing the Safety and Acceptance of a Novel Virtual Reality System to Improve Visual Function

ABSTRACT Purpose To assess the feasibility of the clinical use of a novel Virtual Reality (VR) training software designed to be used for active vision therapy in amblyopic patients by determining its preliminary safety and acceptance on the visual function of healthy adults. Methods Pilot study enrolling 10 individuals (3 men, 7 women, mean age: 31.8 ± 6.5 years) with a best-corrected visual acuity (BCVA) of ≥ .90 (decimal) in both eyes were evaluated before and after 20 minutes of exposure to the NEIVATECH VR system using the HTC Vive Pro Eye head mounted display. Visual function assessment included near (40 cm) and distance (6 m) cover test (CT), stereopsis, binocular accommodative facility (BAF), near point of convergence (NPC), near point of accommodation (NPA), accommodative-convergence over accommodation (AC/A) ratio and positive and negative fusional vergences. Safety was assessed using the VR Sickness Questionnaire (VRSQ) and acceptance using the Technology Acceptance Model ;(TAM). Changes in all these variables after VR exposure were analyzed. Results Short-term exposure to the NEIVATECH VR system only induced statistically significant changes in distance phoria (p = .016), but these changes were not clinically relevant. No significant changes were observed in VRSQ oculo-motricity and disorientation scores after exposure (p = .197 and .317, respectively). TAM scores showed a good acceptance of the system in terms of perceived enjoyment and perceived ease of use, although some concerns were raised in relation to the intention-to-use domain. Conclusion Exposure to the NEIVATECH VR system does not seem to adversely affect the visual function in healthy adults and its safety and acceptance profile seems to be adequate for supporting its potential use in other populations, such as amblyopic patients.

Comparison of Visual Symptom Frequency and Occupational Issues Between Patients With and Without Concussion.

Occupational therapy practitioners' knowledge of and advocacy for clients with visual symptoms postconcussion can have a considerable impact on recovery. To compare the frequency of vision symptoms and occupational performance deficits in a sample of participants with and without concussion. Cross-sectional study. Sports medicine clinic. Adolescents and adults with concussion (n = 20) and musculoskeletal injuries (n = 19). Measures included monocular amplitude of accommodation, near point of convergence, Binocular Vision Assessment (BVA) computerized screening for phoria, BVA computerized screening for fusional vergence, the Developmental Eye Movement Test, the Canadian Occupational Performance Measure, and the Convergence Insufficiency Symptom Survey-Concussion Version (CISS-CON). We found significant differences between participants with and without concussion using the CISS-CON (p = .001), positive fusional vergence (p = .02), and near point of convergence (p = .02). Participants with concussion scoring above cutoffs on multiple measures reported poorer performance (p = .005) and satisfaction (p = .004) with valued occupations. Concussion has a detrimental effect on vision and occupation, and occupational therapy practitioners are well-positioned to assess and address issues arising from this relationship. Plain-Language Summary: Vision symptoms commonly experienced after a concussion are associated with reduced occupational performance and satisfaction and can have a considerable impact on recovery. Occupational therapy assessment for clients with concussion should include screening for vision difficulties.

Comparison of Near Point of Accommodation and Near Point of Convergence with Positive Fusional Vergence among Young Adults, Bengaluru

Background: When encountered with mass screening and increased walk-in patients in outpatient departments (OPD), evaluating complete binocular vision assessment becomes time-consuming. Consequently, there is a need to streamline the testing process. This study also aims to explore if there are any correlations between Near Point of Accommodation (NPA) and Near Point of Convergence (NPC) with Positive Fusional Vergence (PFV). Methodology: A retrospective study was carried out at Sankara Eye Hospital in Bangalore. Data from patients aged 18 to 35, who underwent binocular vision assessment between 2016 and 2020, were included. Out of 101,896 patients who visited the hospital during this period, 3,449 attended the vision therapy clinic. Among them, 1708 patients met the criteria for inclusion, while 1,741 were excluded. Results: Out of 1708 subjects, 759 are females and 949 are males. The relationship between Near Point of Accommodation (NPA), Near Point of Convergence (NPC), and Positive Fusional Vergence (PFV) blur and break values were analysed. A positive correlation was observed between NPA and PFV blur (Spearman's rho = 0.069, p=0.004) and a negative correlation between NPC and PFV break (Spearman's rho = -0.370, p&lt;0.001). There was a significant difference between NPA and PFV blur, as well as NPC and PFV break (p=0.000), emphasizing the importance of incorporating all three tests in a binocular vision assessment. Conclusion: These results emphasize the necessity for complete binocular vision assessment to effectively diagnose and manage binocular vision anomalies. By accounting for the various parameters involved in this investigation, clinicians can enhance the precision and quality of their assessments and plan for appropriate treatment strategies for patients with binocular vision anomalies.