Symptomatic Convergence Insufficiency Research Articles

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.

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.

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.

Neural consequences of symptomatic convergence insufficiency: A small sample study.

Convergence insufficiency (CI) is an oculomotor abnormality characterised by exophoria and inadequate convergence when focusing on nearby objects. CI has been shown to cause symptoms when reading. However, the downstream consequences on brain structure have yet to be investigated. Here, we investigated the neural consequences of symptomatic CI, focusing on the left arcuate fasciculus, a bundle of white matter fibres which supports reading ability and has been associated with reading deficits. We compared the arcuate fasciculus microstructure of participants with symptomatic CI versus normal binocular vision (NBV). Six CI participants and seven NBV controls were included in the analysis. All participants were scanned with 3 T magnetic resonance imaging (MRI), and anatomical and diffusion-weighted images were acquired. Diffusion-weighted images were processed with TRACULA to identify the arcuate fasciculus in each participant and compute volume and radial diffusivity (RD). Compared with NBV controls, those with symptomatic CI had significantly smaller arcuate fasciculi bilaterally (left: t = -3.21, p = 0.008; right: t = -3.29, p = 0.007), and lower RD in the left (t = -2.66, p = 0.02), but not the right (t = -0.81, p = 0.44, false discovery rate (FDR)-corrected p > 0.05) arcuate fasciculus. Those with higher levels of reading symptoms had smaller arcuate fasciculi (r = -0.74, p = 0.004) with lower RD (r = -0.61, p = 0.03). These findings suggest that symptomatic CI may lead to microstructural changes in the arcuate fasciculus. Since it is highly unlikely that abnormalities in the arcuate fasciculus are the cause of the neuromuscular deficits in the eyes, we argue that these changes may be a potential neuroplastic consequence of disruptions in sustained reading.

Altered Large-Scale Resting-State Functional Network Connectivity in Convergence Insufficiency Young Adults Compared With Binocularly Normal Controls.

To investigate the underlying resting-state functional connectivity (RSFC) of symptomatic convergence insufficiency (CI) compared with binocularly normal controls (BNC) using functional magnetic resonance imaging (fMRI) under The Convergence Insufficiency Neuro‑mechanism Adult Population Study (NCT03593031). A total of 101 participants were eligible for this study. After removing datasets with motion artifacts, 49 CI and 47 BNC resting-state functional magnetic resonance imaging datasets were analyzed. CI was diagnosed with the following signs: (1) receded near point of convergence of 6 cm or greater, (2) decreased positive fusional vergence of less than 15∆ or failing Sheard's criteria of twice the near phoria, (3) near phoria of at least 4∆ more exophoric compared with the distance phoria, and (4) symptoms using the Convergence Insufficiency Symptom Survey (score of ≥21). RSFC was assessed using a group-level independent components analysis and dual regression. A behavioral correlation analysis using linear regression method was performed between clinical measures and RSFC using the significant difference between the CI and BNC. On average, a decreased RSFC was observed within the frontoparietal network, default mode network and visual network in patients with CI, compared with the participants with BNC (P < 0.05, corrected for multiple comparisons). The default mode network RSFC strength was significantly correlated with the PFV, near point of convergence, and difference between the horizontal phoria at near compared with far (P < 0.05). Results support altered RSFC in patients with CI compared with participants with BNC and suggest that these differences in underlying neurophysiology may in part be in connection with the differences in optometric visual function used to diagnose CI.

A Systematic Review and Meta-analysis of Convergence Insufficiency Prevalence and Management Options

Background: Convergence insufficiency (CI) is one of the most common binocular vision disorders. The condition negatively affects the quality of life through its impact on near activities, while there is a large gap in the information on its global prevalence and consensus on treatment. Objectives: The purpose of this systematic review and meta-analysis was to assess the prevalence and treatment options available for convergence insufficiency. Methods: The study was performed in 2023 using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA-2020) guidelines. The authors have searched Google Scholar, Research Gate, Scopus, PubMed, Index Medicus, Web of Science, and the JAMA network. This review included peer-reviewed studies published between January 2000 to January 2023 that assessed the prevalence and treatment modalities of convergence insufficiency. Results: The authors screened 13250 studies, 20 for prevalence and 15 for treatment from 12 countries that met the inclusion criteria for the study. The overall pooled prevalence of convergence insufficiency was 7.98%, and the heterogeneity between the studies was highly significant P &lt; 0.0001. Majorities of the studies 12(80%) reported that office-based vision therapy is the most effective treatment of CI, form those studies 5(42.0%) highlighted that office-based vergence/accommodative therapy with home reinforcement is the best modality of treatment. Whereas, home-based pencil push-up therapy, vision therapy with modified refractive correction, and vision therapy with prismatic correction were reported as effective treatment options for CI. The reviewed studies showed that vision therapy is highly effective to recover from symptomatic CI in both adults and children. Conclusion: The prevalence of convergence insufficiency was high, there was highly significant heterogeneity between the reviewed studies. Office-based vergence/accommodative therapy with home reinforcement is the best modality of treatment, followed by home-based pencil push-up therapy, vision therapy with modified refractive correction, and vision therapy with prismatic correction. There is consensus among reviewed studies that vision therapy is highly effective to recover from symptomatic CI in both adults and children.

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.

Relationships among Clinical Factors and Patient-reported Outcome Measures in Adults with Convergence Insufficiency.

When exploring relationships among clinical measures and patient-reported outcome measures in adults with convergence insufficiency, worse symptoms (Convergence Insufficiency Symptom Survey [CISS] score) seemed to be correlated with worse reading function domain score (Adult Strabismus-20 quality-of-life questionnaire). After treatment, improved symptoms were associated with improved reading function quality of life. This study aimed to explore relationships between clinical measures and patient-reported outcome measures in adults undergoing treatment for symptomatic convergence insufficiency. In a prospective multicenter observational study, we evaluated adults with symptomatic convergence insufficiency (i.e., clinical measures of near exodeviation, receded near point of convergence, reduced near positive fusional vergence; CISS score ≥21). Fifty-seven participants treated with vision therapy/exercises (n = 35) or base-in prism (n = 22) were analyzed. Spearman correlation coefficients ( R ) were used to assess associations among the three clinical measures and patient-reported outcome measures (CISS, Diplopia Questionnaire, four Adult Strabismus-20 quality-of-life domains) before treatment (baseline) and after 10 weeks and 1 year. Associations were interpreted to be present when the lower limit of the 95% confidence interval (CI) was moderate to strong ( R ≥ 0.4). Among multiple exploratory analyses, the only moderate to strong baseline correlation was between worse CISS and worse Adult Strabismus-20 reading function scores ( R = 0.62; 95% CI, 0.43 to 0.76). Regarding change in measures with treatment, the only moderate to strong correlations were between improved CISS and improved Adult Strabismus-20 reading function scores for prism at 10 weeks ( R = 0.78; 95% CI, 0.52 to 0.91) and 1 year ( R = 0.85; 95% CI, 0.65 to 0.94) and for vision therapy/exercises at 1 year ( R = 0.78; 95% CI, 0.57 to 0.89). In exploratory analyses, we found positive correlations between CISS symptom scores and reading function quality-of-life scores. The absence of correlations between symptoms and individual clinical measures is consistent with clinical experience that, in convergence insufficiency, symptoms and clinical findings can be discordant.

Botulinum Toxin A Injection for Convergence Insufficiency.

To evaluate the effects of botulinum toxin A injection in one or both lateral rectus muscles in patients with convergence insufficiency previously managed with non-surgical and/or surgical options other than botulinum toxin A injection. All patients with symptomatic convergence insufficiency treated with botulinum toxin A injection to one or both lateral rectus muscles from 2013 to 2018 at the Department of Ophthalmology, Rigshospitalet-Glostrup, Copenhagen University Hospital were retrospectively reviewed. All patients had near symptoms and were previously treated with a combination of convergence exercises, prisms, and/or surgery. Patients with previous botulinum toxin A injection in an extraocular muscle were excluded. Reading symptoms and deviation at near and distance were recorded at baseline and after 1 and 6 months. Twenty-three patients with convergence insufficiency were included (8 men and 15 women). Follow-up was conducted after a median of 47 days (interquartile range [IQR]: 31.5 to 72.5 days) and 174 days (IQR: 139 to 267 days). At baseline, median near angle of deviation was 18 PD of exophoria (IQR: 13 to 21 PD). The near deviation was reduced to 10 PD of exophoria (IQR: 7 to 17 PD) at first follow-up visit and 14 PD of exophoria (IQR: 12 to 18 PD) at last follow-up visit. Thirteen of 23 patients (57%) and 3 of 13 patients (23%) reported improvement in reading symptoms at first and last follow-up visit, respectively, compared to baseline. Botulinum toxin A injection may be useful in patients with convergence insufficiency. However, some patients may require repeated injections. [J Pediatr Ophthalmol Strabismus. 2023;60(2):108-113.].

Does coexisting accommodative dysfunction impact clinical convergence measures, symptoms and treatment success for symptomatic convergence insufficiency in children?

To determine whether coexisting accommodative dysfunction in children with symptomatic convergence insufficiency (CI) impacts presenting clinical convergence measures, symptoms and treatment success for CI. Secondary data analyses of monocular accommodative amplitude (AA; push-up method), monocular accommodative facility (AF; ±2.00D lens flippers) and symptoms (CI Symptom Survey [CISS]) in children with symptomatic CI from the Convergence Insufficiency Treatment Trial (N=218) and CITT-Attention and Reading Trial (N=302) were conducted. Decreased AA was defined as more than 2D below the minimum expected amplitude for age (15 - ¼ age); those with AA<5D were excluded. Decreased AF was defined as <6 cycles per minute. Mean near point of convergence (NPC), near positive fusional vergence (PFV) and symptoms (CISS) were compared between those with and without accommodative dysfunction using analysis of variance and independent samples t-testing. Logistic regression was used to compare the effect of baseline accommodative function on treatment success [defined using a composite of improvements in: (1) clinical convergence measures and symptoms (NPC, PFV and CISS scores) or (2) solely convergence measures (NPC and PFV)]. Accommodative dysfunction was common in children with symptomatic CI (55% had decreased AA; 34% had decreased AF). NPC was significantly worse in those with decreased AA (mean difference=6.1cm; p<0.001). Mean baseline CISS scores were slightly worse in children with coexisting accommodative dysfunction (decreased AA or AF) (30.2 points) than those with normal accommodation (26.9 points) (mean difference=3.3 points; p<0.001). Neither baseline accommodative function (p≥0.12 for all) nor interaction of baseline accommodative function and treatment (p≥0.50) were related to treatment success based on the two composite outcomes. A coexisting accommodative dysfunction in children with symptomatic CI is associated with worse NPC, but it does not impact the severity of symptoms in a clinically meaningful way. Concurrent accommodative dysfunction does not impact treatment response for CI.

Convergence insufficiency symptom survey (CISS) scores are predictive of severity and number of clinical signs of convergence insufficiency in young adult Africans

PurposeThis study aimed to investigate the correlation between convergence insufficiency symptom survey (CISS) score and the signs of convergence insufficiency (CI) and to evaluate the sensitivity and specificity of the CISS to predict CI and ametropia among young adult university students. MethodThis prospective cross-sectional clinic-based study included 300 first year university students (mean age = 21.58 (SD ± 2.2) years) who consecutively reported for eye examination. Participants were administered the CISS questionnaire and investigated for the signs of CI. Diagnosis of CI was based on presence of three or four signs. The correlation between the CISS score and the signs of CI were determined and Receiver Operation Characteristics (ROC) curves were used to evaluate sensitivity and specificity. ResultsThere were significant correlations between CISS score and the clinical signs of CI namely NPC break (rs = 0.622, p = 0.0001), NPC recovery (rs = 0.620, p = 0.0001), near exophoria (rs = 0.434, p = 0.0001), near PFV blur (rs = -0.359, p = 0.0001), near PFV break (-0.306, p = 0.0001), near PFV recovery (rs = -0.326, p = 0.0001) and gradient AC/A ratio (rs = -0.290, p = 0.0001). There was a significant positive correlation between CISS score and the number of clinical signs of CI (rs = 0.575, p-value = 0.0001). The CISS had good sensitivity (AOC = 0.882) to predict CI and poor sensitivity (AOC = 0.642) to predict ametropia. ConclusionThe CISS score is correlated with the severity and number of signs of CI in young adult Ghanaian university students. Its use in addition to clinical investigative testing may give a definitive diagnosis of symptomatic CI.

Convergence Insufficiency Neuro-Mechanism Adult Population Study: Phoria Adaptation Results

PurposeThe purpose of this study was to compare changes in phoria adaptation between young adult binocularly normal controls (BNCs) and participants with symptomatic convergence insufficiency (CI), who were randomized to either office-based vergence accommodative therapy (OBVAT) or office-based placebo therapy (OBPT).MethodsIn the double-masked randomized clinical trial, 50 BNC and 50 CI participants were randomized to the following therapeutic interventions: OBVAT or OBPT with home reinforcement for 12 one-hour office sessions. A 6∆ base-out and 6∆ base-in phoria adaptation experiment at near (40 cm) was conducted using the flashed Maddox rod technique at baseline and at outcome. Measurements included the rate and the magnitude of phoria adaptation.ResultsAt baseline, BNC and CI participants had significantly different rates and magnitudes of base-in and base-out phoria adaptation (P < 0.001). When comparing the outcome to baseline measurements, significant main effect differences in longitudinal measurements were observed for the magnitude and the rate of phoria adaptation for both base-out and base-in experiments (P < 0.05). For the magnitude and rate of phoria adaptation, post hoc analyses using paired t-tests revealed that the CI group administered the OBVAT intervention exhibited a significant increase in the magnitude and rate of phoria adaptation compared to baseline for both base-in and base-out phoria adaptation (P < 0.01) but not for those administered OBPT.ConclusionsPhoria adaptation is significantly different at baseline between those with normal binocular vision and symptomatic CI participants. OBVAT significantly improves the rate and magnitude of both base-out and base-in phoria adaptation at near compared to OBPT. Results have clinical implications for new therapeutic interventions.

Home- and Office-Based Vergence and Accommodative Therapies for Treatment of Convergence Insufficiency in Children and Young Adults: A Report by the American Academy of Ophthalmology

To review home- and office-based vergence and accommodative therapies for treatment of convergence insufficiency (CI) in children and young adults up to 35 years of age. Literature searches were conducted through October 2020 in the PubMed database for English-language studies. The combined searches yielded 359 abstracts, of which 37 were reviewed in full text. Twelve of these were considered appropriate for inclusion in this assessment and assigned a level of evidence rating by the panel methodologist. Of the 12 studies included in this assessment, 8 were graded as level I evidence, 2 were graded as level II evidence, and 2 were graded as level III evidence. Two of the level I studies included older teenagers and young adults; the remainder of the studies exclusively evaluated children. Two randomized controlled trials found that office-based vergence and accommodative therapies were effective in improving motor outcomes in children with symptomatic CI. However, the studies reported conflicting results on the efficacy of office-based therapy for treating symptoms of CI. Data were inconclusive regarding the effectiveness of home-based therapies (including pencil push-ups and home computer therapy) compared with home placebo. In young adults, office-based vergence and accommodative therapies were not superior to placebo in relieving symptoms of CI. Level I evidence suggests that office-based vergence and accommodative therapies improve motor outcomes in children with symptomatic CI, although data are inconsistent regarding symptomatic relief.Evidence is insufficient to determine whether home-based therapies are effective.

Underlying neurological mechanisms associated with symptomatic convergence insufficiency

Convergence insufficiency (CI) is the most common binocular vision problem, associated with blurred/double vision, headaches, and sore eyes that are exacerbated when doing prolonged near work, such as reading. The Convergence Insufficiency Neuro-mechanism Adult Population Study (NCT03593031) investigates the mechanistic neural differences between 50 binocularly normal controls (BNC) and 50 symptomatic CI participants by examining the fast and slow fusional disparity vergence systems. The fast fusional system is preprogrammed and is assessed with convergence peak velocity. The slow fusional system optimizes vergence effort and is assessed by measuring the phoria adaptation magnitude and rate. For the fast fusional system, significant differences are observed between the BNC and CI groups for convergence peak velocity, final position amplitude, and functional imaging activity within the secondary visual cortex, right cuneus, and oculomotor vermis. For the slow fusional system, the phoria adaptation magnitude and rate, and the medial cuneus functional activity, are significantly different between the groups. Significant correlations are observed between vergence peak velocity and right cuneus functional activity (p = 0.002) and the rate of phoria adaptation and medial cuneus functional activity (p = 0.02). These results map the brain-behavior of vergence. Future therapeutic interventions may consider implementing procedures that increase cuneus activity for this debilitating disorder.

Negative Fusional Vergence Is Abnormal in Children with Symptomatic Convergence Insufficiency.

Deficits of disparity divergence found with objective eye movement recordings may not be apparent with standard clinical measures of negative fusional vergence (NFV) in children with symptomatic convergence insufficiency. This study aimed to determine whether NFV is normal in untreated children with symptomatic convergence insufficiency and whether NFV improves after vergence/accommodative therapy. This secondary analysis of NFV measures before and after office-based vergence/accommodative therapy reports changes in (1) objective eye movement recording responses to 4° disparity divergence step stimuli from 12 children with symptomatic convergence insufficiency compared with 10 children with normal binocular vision (NBV) and (2) clinical NFV measures in 580 children successfully treated in three Convergence Insufficiency Treatment Trial studies. At baseline, the Convergence Insufficiency Treatment Trial cohort's mean NFV break (14.6 ± 4.8Δ) and recovery (10.6 ± 4.2Δ) values were significantly greater (P < .001) than normative values. The post-therapy mean improvements for blur, break, and recovery of 5.2, 7.2, and 1.3Δ, respectively, were statistically significant (P < .0001). Mean pre-therapy responses to 4° disparity divergence step stimuli were worse in the convergence insufficiency group compared with the NBV group for peak velocity (P < .001), time to peak velocity (P = .01), and response amplitude (P < .001). After therapy, the convergence insufficiency group showed statistically significant improvements in mean peak velocity (11.63°/s; 95% confidence interval [CI], 6.6 to 16.62°/s), time to peak velocity (-0.12 seconds; 95% CI, -0.19 to -0.05 seconds), and response amplitude (1.47°; 95% CI, 0.83 to 2.11°), with measures no longer statistically different from the NBV cohort (P > .05). Despite clinical NFV measurements that seem greater than normal, children with symptomatic convergence insufficiency may have deficient NFV when measured with objective eye movement recordings. Both objective and clinical measures of NFV can be improved with vergence/accommodative therapy.

Interventions for convergence insufficiency: a network meta-analysis.

Interventions for convergence insufficiency: a network meta-analysis.

Convergence Insufficiency Neuro-mechanism in Adult Population Study Randomized Clinical Trial: Clinical Outcome Results.

These data confirm the effectiveness of office-based vergence/accommodative therapy for improving the near point of convergence and positive fusional vergence in young adults with symptomatic convergence insufficiency within a double-masked longitudinal randomized clinical trial. This study aimed to report changes in clinical signs and symptoms of convergence insufficiency from a randomized clinical trial evaluating the effectiveness of office-based vergence/accommodative therapy for young adults with symptomatic convergence insufficiency. In this double-masked, randomized clinical trial, convergence insufficiency patients (n = 50; average age, 21 ± 3 years; range, 18 to 32 years) were randomized to either office-based vergence/accommodative therapy or office-based placebo therapy. Improvements in (1) near point of convergence, (2) positive fusional vergence, and (3) self-reported symptoms (Convergence Insufficiency Symptom Survey [CISS] score) were evaluated after twelve 1-hour sessions of treatment within the office comparing the results from the vergence/accommodative therapy and the placebo therapy groups. The mean near point of convergence improved by 6.0 and 3.1 cm in the vergence/accommodative and placebo therapy groups, respectively (mean difference of -2.9 cm; 95% confidence interval [CI], -4.6 to -1.0 cm; P < .01). The mean positive fusional vergence increased by 17.3 and 7.4Δ in the vergence/accommodative and placebo therapy groups, respectively (mean difference of 9.9Δ; 95% CI, 4.9 to 16.0Δ; P < .001). The mean CISS score improved by 12.4 and 10.1 points in the vergence/accommodative and placebo therapy groups, respectively (mean difference of 2.3 points; 95% CI, -8.3 to +4.6 points; P = .56). Our results demonstrate that office-based vergence/accommodative therapy is effective for improving the near point of convergence and positive fusional vergence in young adults with symptomatic convergence insufficiency. However, given that both treatment groups had a similar reduction in self-reported symptoms, we recommend that the CISS be revised if it is to be used as an outcome measure in future studies of convergence insufficiency.

Effectiveness of vergence/accommodative therapy for accommodative dysfunction in children with convergence insufficiency.

To determine the effectiveness of office-based vergence/accommodative therapy for improving accommodative amplitude and accommodative facility in children with symptomatic convergence insufficiency and accommodative dysfunction. We report changes in accommodative function following therapy among participants in the Convergence Insufficiency Treatment Trial - Attention and Reading Trial with decreased accommodative amplitude (115 participants in vergence/accommodative therapy; 65 in placebo therapy) or decreased accommodative facility (71 participants in vergence/accommodative therapy; 37 in placebo therapy) at baseline. The primary analysis compared mean change in amplitude and facility between the vergence/accommodative and placebo therapy groups using analyses of variance models after 4, 8, 12 and 16weeks of treatment. The proportions of participants with normal amplitude and facility at each time point were calculated. The average rate of change in amplitude and facility from baseline to week 4, and from weeks 4 to 16, were determined in the vergence/accommodative therapy group. From baseline to 16weeks, the mean improvement in amplitude was 8.6 dioptres (D) and 5.2D in the vergence/accommodative and placebo therapy groups, respectively (mean difference=3.5D, 95% confidence interval (CI): 1.5 to 5.5D; p=0.01). The mean improvement in facility was 13.5 cycles per minute (cpm) and 7.6cpm in the vergence/accommodative and placebo therapy groups, respectively (mean difference=5.8cpm, 95% CI: 3.8 to 7.9cpm; p<0.0001). Significantly greater proportions of participants treated with vergence/accommodative therapy achieved a normal amplitude (69% vs. 32%, difference=37%, 95% CI: 22 to 51%; p<0.0001) and facility (85% vs. 49%, difference=36%, 95% CI: 18 to 55%; p<0.0001) than those who received placebo therapy. In the vergence/accommodative therapy group, amplitude increased at an average rate of 1.5D per week during the first 4weeks (p<0.0001), then slowed to 0.2D per week (p=0.002) from weeks 4 to 16. Similarly, facility increased at an average rate of 1.5cpm per week during the first 4weeks (p<0.0001), then slowed to 0.6cpm per week from weeks 4 to 16 (p<0.0001). Office-based vergence/accommodative therapy is effective for improving accommodative function in children with symptomatic convergence insufficiency and coexisting accommodative dysfunction.

BYNOCS®1 – A Cloud-Based Indigenous Tele-Health Vision Therapy Software for the Assessment and Management of Binocular Vision Disorders

Background: Binocular vision assessment is an integral part of an eye and vision care practice. With the need for a user friendly, simplified, and comprehensive tool especially in this digital era, we propose a new indigenous cloudbased software, Bynocs.® This manuscript describes the technical details, the functioning of this indigenous software, and a case series demonstrating the application and efficacy of Bynocs® as a tele-health vision therapy tool. All the three cases were handled remotely through the Bynocs tele-health vision therapy platform. Case Reports: Case 1: This is a case of symptomatic convergence insufficiency who had prior compliance issues with a conventional vision therapy approach. With 10 sessions of Bynocs vision therapy focused on improving convergence amplitudes, the patient showed significant improvements in both subjective and objective parameters. Case 2: This case is of a 12 year old child with residual anisometropic amblyopia who had excellent compliance with patching therapy for 3 years but visual acuity had plateaued over the last 6 months. After 20 sessions of Dichoptic amblyopia therapy, best-corrected visual acuity (BCVA) improved by 3 log MAR lines, with improvements in stereoacuity to 100 sec of arc. Case 3: This case of a 10 year old child with residual exophoria after strabismus surgery was referred for managing the residual deviation and associated visual complaints. The child had 20/20 visual acuity in both eyes and 10 prism diopters of residual exophoria at distance and near. After 30 sessions of vision therapy, improvements in fusional vergence amplitudes was achieved along with the deviation restoring to orthophoria at both distance and near, with further improvements in stereoacuity from 400 sec of arc to 120 sec of arc. Conclusions: As tele-health is finding favor across the globe, Bynocs® can be a valuable tele-health vision therapy tool for in the management of binocular vision anomalies and amblyopia with the functionality for remote diagnosis and therapy.

Vergence Eye Movements: From Basic Science to Clinical Application - Foreword to the Special Issue.

The abstract book of the last European Conference on Eye Movements [1] lists abstracts of 373 presentations, but less than five percent investigate vergence eye movements, i.e. the coordination of the right and left eye. Why then a special issue on this neglected issue? Human vision under natural conditions involves both eyes in coordination controlled by interacting processes subsumed under the concept of vergence.. Further, vergence is important for people in their daily lives since disorders of vergence can have serious consequences: ophthalmologists deal with squinting patients on the basis of heterophoria and heterotropia testing, eye strain or visual complaints can be related to impaired vergence dynamic or less accurate static vergence, remediation by optometrist includes vergence training or prism eye glasses, etc.