Effectiveness of Therapy for the Treatment of Accommodative Insufficiency: An Open Pilot Study

Background: To evaluate improvements in clinical measures and symptoms in children and young adults with accommodative insufficiency in an open trial of office-based vergence and accommodative therapy. Methods: Major eligibility requirements included ages 9 to 30 years and amplitude of accommodation (AA) ≥2 diopters (D) below Hoffstetter’s minimum. Participants completed 8 weekly, 1-hour sessions of office-based vergence and accommodative therapy. Therapy procedures followed the Convergence Insufficiency Treatment Trial (CITT) therapy protocol with emphasis on accommodative procedures. Clinical measures of accommodation and symptoms (Convergence Insufficiency Symptom Survey [CISS]) were assessed at baseline and after therapy. Results were evaluated using the Student’s t test and Kruskal-Wallis test. Repeatability of CISS scores at baseline was assessed using Bland Altman 95% Limits of Agreement (LoA) and Interclass Correlation Coefficient (ICC). Results: Eighteen participants (mean age 17.4 ± 8.0 years) were enrolled; sixteen completed the study. The mean AA improved significantly from 5.5D OD and OS at baseline to 12.4D OD and 12.8D OS at outcome (p<0.001). Mean monocular accommodative facility (AF) also increased significantly in both eyes from 6.6 cycles per min (cpm) OD and 7.4cpm OS at baseline to 14.2cpm OD and OS at outcome (p≤0.0009). Amplitude-scaled monocular AF also showed significant improvements (p≤0.034 for both). Mean CISS score improved 10.50 points (p=0.0003). Significantly greater improvements in AA were observed in children (9.0D) than in adults (4.3D) in the right eye (p=0.007 for both comparisons). Conversely mean improvement in CISS score was significantly greater in adults than in children (p=0.039). Repeated CISS scores differed by, on average,1.47 points (95% limits of agreement:-5.19, 8.13; p=0.12). The ICC was 0.95 with a 95% confidence interval of 0.87 to 0.98. Conclusion: Eight weekly sessions of office-based accommodative vergence therapy combined with homebased- reinforcement therapy resulted in improvements of symptoms and clinical measures of accommodation in children and young adults with accommodative insufficiency.

Veränderung des NPC bei Personen mit Konvergenzinsuffizienz nach I.F.S.-Visualtraining

Purpose. The aim of this study was to evaluate the efficacy of the I.F.S. visual therapy (convergence training) developed by Bruce Evans in a randomized-controlled setting. The analysis of the changes of the near point of convergence (NPC) was the main target of the study. Material and Methods. 20 subjects (39.0 ± 15.32 years) with convergence insufficiency and an NPC > 10 cm underwent 4 weeks of visual therapy in a randomised-controlled singleblind setting. The verum group followed the I.F.S. exercises, while the control group performed a placebo therapy. Before and after the training phase, the NPC and the positive fusional vergence (PFV) were measured in all subjects and the Sheard and Mallett criteria were also assessed. The CISS questionnaire was used to record and quantify subjective symptoms. Results. The statistical analysis (α = 0.05) shows that the NPC of the verum group improved significantly compared to the control group (p = 0.0008) and within the verum group only (p = 0.0002). The positive effect of the I.F.S. exercises is confirmed by the also significant improvement of the PFV. Conclusion. The results as well as the practical experience with the exercises indicate that the I.F.S. visual therapy proves to be effective for individuals with a convergence insufficiency and an NPC > 10 cm in improving the near point of convergence. Keywords. convergence insufficiency, near point of convergence, NPC, visual therapy, convergence training, I.F.S. exercises

Refractive Errors and Binocular Vision Anomalies among Young University Students

It has been reported that refractive errors (RE) and binocular vision (BV) anomalies are common among university students. In this study we aimed to assess RE and BV status among university students in Saudi Arabia, and its relation to the academic performance. We recruited 109 participants (aged from 18 to 21 years). Visual acuity (VA) and objective refraction were used to assess the refractive status. Cover test, near-point convergence (NPC) and stereopsis tests were used to assess the BV status. Convergence insufficiency symptom survey (CISS) was applied to quantify near-work related symptoms. Mann-Whitney U test (p value was set as p &lt; 0.05) was used to compare VA, CISS, NPC and the academic performance between the groups who had heterophoria versus orthophoria. We found that there was only 38% emmetrope, while the percentage of heterophoria was 45.8%. The academic performance was not statistically different among the two groups, but CISS and stereopsis scores were significantly different (p &lt; 0.03). We concluded that RE and BV anomalies were common among university students in Saudi Arabia, but did not affect the academic performance. More studies are warranted to understand the low scores of CISS and stereoacuity, and their association with RE and BV anomalies.

Ophthalmic Causes of Headache among Patients Attending Tertiary Care Center in Kathmandu, Nepal

The purpose of this study was to evaluate the ophthalmic causes of headache among patients attending tertiary care hospital. This was a descriptive, cross sectional hospital-based study. One hundred and thirty-two patients with ocular cause of headache excluding primary headache and pediatrics patients during one year were included. Detail ocular examination was done including visual acuity, refraction, binocular vision assessment like convergence insufficiency and fusional insufficiency, anterior and posterior segment examination. Among headache patients, female was 106 (80.3%) and male was 26 (19.7%). The prevalence of headache in female was 6.9% and in male was 2%. Headache was more common in age group 18-29 (59.8%). The mean age of presentation was 29.9 ± 10.2 years (range 18-61 years). Out of 132 patients with headache, 104 (78.8%) had refractive error, 15 (11.4%) had fusional insufficiency, 6 (4.5%) had convergence insufficiency, 10 (7.6%) had anterior segment diseases and 5 (3.8%) had posterior segment diseases. Among refractive errors, both eyes astigmatism was the commonest 48 (36.5%) followed by both eyes simple myopia 44 (33.4 %) which was statistically significant with ocular headache (p=0.000). Ocular anomalies other than refractive error may coexist with headache complaints. Therefore, thorough ocular examination should be done in all patients suffering from headache.

Effect of Applying Binocular Visual Training after Slanted Lateral Rectus Recession on Orthophoric Rate and Binocular Visual Function Recovery on Patients with Convergence Insufficiency-Type Intermittent Exotropia

Objective. To explore the effect of applying binocular visual training after slanted lateral rectus recession on orthophoric rate and binocular visual function recovery on patients with convergence insufficiency-type intermittent exotropia (CI-IXT). Methods. A total of 76 CI-IXT child patients treated at the Strabismus and Pediatric Ophthalmology Department of our hospital from June 2019 to June 2020 were selected as the research objects, and those who met the inclusion criteria were equally divided into group A (63 eyes) and group B (61 eyes) according to the sealed envelope randomization. All child patients accepted the slanted lateral rectus recession, and after that, those in group A accepted the binocular visual training and those in group B accepted the conventional visual function rehabilitation training, so as to compare their position of eye, the best corrected visual acuity, etc., after training for statistical analysis. Results. Compared with group B after one month of surgery, group A had significantly less patients with grade I binocular vision function ( P < 0.001) and more patients with grade II and III vision function ( P < 0.05); between group A and group B, after 3 months and 6 months of treatment, the number of eyes with normal stereoscopic vision was significantly higher in group A ( P < 0.05); at 15 days, 1 month, 3 months, and 6 months of treatment, the visual strain scores of group A were significantly lower ( P < 0.001); after treatment, the number of orthophoria eyes was significantly higher in group A ( P < 0.001), while the numbers of overcorrected eyes and undercorrected eyes were significantly higher in group B ( P < 0.001); and the total incidence rate of adverse reactions was significantly lower in group A ( P < 0.05). Conclusion. Applying binocular visual training to child patients with CI-IXT after slanted lateral rectus recession can promote the recovery of binocular vision and ensure higher safety, and further study will help to establish a better solution for the affected children.

Virtual Reality-based Vision Therapy Versus OBVAT in the Treatment of Convergence Insufficiency, Accommodative Dysfunction: A Randomized Controlled Trial

Background: Virtual reality is being increasingly applied in vision therapy. However, the differences in effectiveness, optimal treatment cycle, and prognosis between virtual reality-based vision therapy and traditional therapies remain unknown. The purpose of this study was to compare the effectiveness of virtual reality-based vision therapy and office-based vergence/accommodative therapy in young adults with convergence insufficiency or accommodative dysfunction.Methods: The patients were randomly assigned to either the virtual reality-based vision therapy group or the office-based vergence/accommodative therapy group. The vision therapy lasted 12 weeks (1 h/week) in both groups. Binocular visual functions (vergence and accommodation) were measured and a subjective questionnaire-based assessment was performed at baseline and after 6 and 12 weeks of therapy.Results: In total, 33 patients with convergence insufficiency and 30 with accommodative dysfunction completed the study. After 12 weeks of treatment for convergence insufficiency, the Convergence Insufficiency Symptom Survey score (F2,31 = 13.704, P < 0.001), near point of convergence (F2,31 = 21.774, P < 0.001), positive fusional vergence (F2,31 = 71.766, P< 0.001), and near horizontal phoria (F2,31 = 16.482, P < 0.001) improved significantly in both groups. Moreover, the monocular accommodative amplitude (F2,25 = 22.154, P < 0.001) and monocular accommodative facility (F2,25 = 86.164, P < 0.001) improved significantly in both groups after 12 weeks of treatment. A statistically significant difference was observed in monocular accommodative facility (F1,25 = 8.140, P = 0.009) between the two groups, but not in other vergence and accommodative functions (0.098 < P < 0.687).Conclusion: Virtual reality-based vision therapy significantly improved binocular vision functions and symptoms in patients with convergence insufficiency and accommodative dysfunction, thereby suggesting its effectiveness as a new optional or additional treatment for young adults with these conditions.Trial registration: This study was registered at the Chinese Clinical Trials Registry on 16/04/2019 (identifier: ChiCTR1900022556).

Prevalence of strabismus among preschool children in eastern China and comparison at a 5-year interval: a population-based cross-sectional study

ObjectiveTo update data on strabismus and evaluate the changes in prevalence and patterns among preschoolers in eastern China over a period of 5 years.DesignNanjing Eye Study, a longitudinal population-based study.SettingRecruitment and testing in kindergartens in Yuhuatai District, Nanjing.Participants2300 eligible children.Main outcome measuresComprehensive ocular examinations were conducted in 1986 children aged 48–<60 months in Nanjing Eye Study (NES, 2016–2017), including visual acuity, ocular alignment, refractive error and ocular structures evaluation. The prevalence rate and pattern of strabismus were calculated and compared with those from the Nanjing Pediatric Vision Project (NPVP, 2011–2012) in children of the same age, of the same area and using the same diagnostic criteria.ResultsThe overall prevalence rate of strabismus in NES was 5.56% (95% CI 4.54% to 6.57%), which was not significantly different from that in NPVP (4.99%, 95% CI 4.13% to 5.84%, p=0.40). The prevalence of subtypes of strabismus underwent significant changes, with significant increase in intermittent exotropia (IXT) in NES (2.78% vs 4.69%, p=0.001) and significant decrease in constant exotropia (1.17% vs 0.15%, p<0.001). Significant change in pattern was observed in IXT, where the proportion of the convergence insufficiency type (2.90% vs 27.17%) increased and exceeded the divergence excess type (20.29% vs 11.96%) to be the second common type (p<0.001).ConclusionThe prevalence of strabismus appeared stable in children aged 48–<60 months in eastern China at a 5-year interval. The prevalence of IXT increased significantly, and the convergence insufficiency type became more prevalent in patients with IXT. Timely detection and intervention of IXT are important among preschoolers.