Binocular Visual Function Research Articles

Efficacy of anti-suppression therapy in improving binocular vision in children with small-angle Esotropia

PurposeTo evaluate the efficacy of anti-suppression exercises in children with small-angle esotropia in achieving binocular vision. MethodsA retrospective review of patients aged 3–8 years who underwent anti-suppression exercises for either monocular or alternate suppression between January 2016 and December 2021 was conducted. Patients with esotropia less than 15 prism diopters (PD) and visual acuity ≥ 6/12 were included. Patients with previous intra-ocular surgery or less than three-month follow-up were excluded. Success was defined as the development of binocular single vision (BSV) for distance, near, or both (measured clinically with either the 4 prism base out test or Worth four dot test) and maintained at two consecutive visits. Qualified success was defined as the presence of diplopia response for both distance and near. Additionally, improvement in near stereo acuity was measured using the Stereo Fly test. ResultsEighteen patients with a mean age of 5.4 ± 1.38 years (range 3–8 years) at the time of initiation of exercises were included in the study. The male female ratio was 10:8. The mean best corrected visual acuity was 0.18 LogMAR unit(s) and the mean spherical equivalent was +3.8 ± 0.14 diopters (D). The etiology of the esotropia was fully accommodative refractive esotropia (8), microtropia (1), post–operative infantile esotropia (4), partially accommodative esotropia (1), and post-operative partially accommodative esotropia (4). Patients received either office-based, home-based, or both modes of treatment for an average duration of 4.8 months (range 3–8). After therapy, BSV was achieved for either distance or near in 66.6 % of patients (95 % CI = 40.03–93.31 %). Binocular single vision for both distance and near was seen in 50 % of children. Qualified success was observed in 38.46% of patients. Persistence of suppression was observed in one patient (5.5 %). Near stereopsis improved to 200 s of arc or more in 60% of the patients. The mean esotropia reduced from 5.7 ± 4.0 PD for distance and 6.2 ± 4.66 PD for near to 2.7 ± 2.4 PD and 3.38 ± 4.7 PD respectively, at the last follow-up (p-value 0.004 and 0.006). Failure of therapy was noticed after six months of follow-up in the child with infantile esotropia. ConclusionAnti-suppression exercises may be beneficial to improve binocular vision functions in children with small-angle esotropias of variable etiologies. Recurrence of suppression after cessation of therapy is possible, warranting regular follow up.

Clinical outcomes in eyes with diffractive continuous depth-of-focus intraocular lenses enhanced for near vision: comparison with trifocal intraocular lenses

BackgroundTo prospectively evaluate visual functions and patient satisfaction after bilateral implantation of diffractive continuous depth-of-focus intraocular lens (CDF IOL) compared with trifocal IOLs.MethodsThis investigator-initiated study was approved by a certified local review board (registered: jRCTs032210305). CDF IOL (Synergy, J&J, group S) and trifocal IOL (AcrySof PanOptix, Alcon, group P) were implanted bilaterally in 30 patients each. Three months postoperatively, binocular outcomes of uncorrected (BUCVA) and distance-corrected (BDCVA) visual acuities at distances of 0.3, 0.4, 0.5, 0.7, and 5 m were measured. Contrast sensitivities were binocularly measured using CSV-1000 (2.5 m) and Pelli-Robson charts at distances of 0.4 and 1 m. Symptoms of glare, halo, starburst, and waxy vision, and satisfaction for near, intermediate, and far visions were assessed with questionnaires. Differences between the two groups were examined.ResultsTwenty-seven patients each completed the follow-up. The mean age of the group S was lower than that of the group P (P < 0.001). The BUCVA at 0.4 m was better in the S group, while the mean manifest refraction of the P group showed a significant hyperopic shift (P < 0.001). BDCVA was significantly better in the S group. The contrast sensitivity results at three distances showed no discernible differences. Although more patients in the S group reported significant glare and halo, their satisfaction with near vision was higher.ConclusionsThe binocular visual function of patients with CDF IOLs was comparable to or better than that of patients with trifocal IOLs. The patients were satisfied with near vision, despite the enhanced glare and halo. Understanding the differences between the two types of presbyopia-correcting IOLs is important to ensure patient satisfaction.Trial registrationThis clinical trial was registered in the Japan Registry for Clinical Research (identifier: jRCTs032210305) on September 13, 2021.

Binocular Function in Adults Before and after Strabismus Surgery

Purpose: To evaluate the state of binocular vision, the amount and direction of the ocular deviation before and after strabismus surgery in adult patients and to monitor the occurrence of postoperative complications. Methods: The retrospective study of 58 adult patients with selected types of strabismus who were surgically treated in the Eye Department of the Tomas Bata Regional Hospital in Zlín. We evaluated the amount and the degree of the primary ocular deviation and the binocular alignment before and after surgery, as well as the state of binocular vision after surgery and the occurrence of postoperative complications. Results: The average deviation in convergent strabismus before surgery was +23.46 degrees, after surgery +6.6 degrees, in divergent strabismus it was -21.5 degrees, after surgery -1.48 degrees, for vertical strabismus before surgery +12.5 degrees and +3.75 degrees after surgery and in paralytic strabismus +20 degrees before surgery and +3 degrees postoperatively. Preoperatively there was effectively no binocular vision in up to 63.9% of patients, superposition occurred in 31%, fusion in 5.1%. No patient had stereopsis before surgery. After surgery, superposition was present in 39.7%, fusion in 31% and stereopsis in 6.9% of patients. Only 22.4% of patients experienced no binocular vision after surgery. Of the selected 21 patients out of 58 with an observation period of at least 3 years, we observed an improvement or development of binocular vision functions after surgery in 12 patients and no improvement of binocular vision functions in 9 patients. In the first group, 58.3% had a stable deviation throughout the follow-up period. While in the second group the deviation was stable in only 33.3%. We can assume that the improvement in binocular vision function after strabismus surgery, leads to a greater longer-term stability of postoperative deviations. Conclusion: Strabismus surgery in adult patients is an effective and safe method, which is not only a cosmetic procedure used to adjust the position of the eyes, but also enables us to induce or improve the state of binocular vision functions.

Clinical Outcomes and Nutritional Status of Children with Intermittent Exotropia Treated with Surgery During the Preschool and Post-School Age

In this study, we compared the clinical outcomes and differences in nutritional status between preschool and post-surgical treatment of intermittent exotropia. We selected 100 children with intermittent exotropia between August 2019 and August 2022 for the study. Among them, 42 children received surgical treatment before school age (4–6 years) and were considered to be in group A, whereas 58 children received surgical treatment after school age (7–12 years) and were considered to be in group B. We found no difference in orthokeratology, overcorrection, or undercorrection rates between the two groups of children before and after surgery (P &gt; 0.05), and the strabismus was lower at 6 and 12 months after surgery than before surgery and lowest at 12 months after surgery (P &lt; 0.05). In addition, the normal rates of visual function, fusion function, and binocular stereopsis were higher in group A than in the control group at 6 and 12 months postoperatively (P &lt; 0.05). The Child Intermittent Exotropia Questionnaire scores were higher in both groups at 12 months postoperatively than at 6 months and were higher in group A than in group B (P &lt; 0.05). Family members of children in group A were more satisfied with the treatment than in group B (P &lt; 0.05), but the difference in albumin, transferrin, and proalbumin before and after surgery was lower in group B than in group A (P &lt; 0.05). It follows that performing intermittent exotropia surgery before school age can more effectively improve the prognosis of children’s binocular visual function, whereas performing intermittent exotropia after school age has less impact on nutritional status.

Effect of visual perception training on binocular visual function reconstruction in patients after strabismus surgery.

To explore the effect of visual perception learning software training (VPT) on binocular visual function reconstruction in children with intermittent exotropia after strabismus surgery. Ninety children with intermittent exotropia admitted to our hospital from June 2018 to December 2018 were included, and randomly divided into VPT and control groups. Children in the control group received basic binocular vision training, while those in the VPT group received VPT after strabismus surgery. Tertiary visual function, visual perception function, Newcastle Control Score (NCS), and ocular position retraction rate were compared at 3 and 12mo after the surgery. At 3 and 12mo after the surgery, the proportion of simultaneous perception, binocular fusion version and binocular stereo vision in the VPT group was conspicuously higher than that in the control group (P<0.05). After the vision training, the binocular visual perception functions of children in both groups were significantly improved compared with that before training (P<0.05). Interestingly, the grating sharpness, texture perception and texture motion perception in the VPT group were dramatically better than control group (P<0.01). The NCS in the VPT group was significantly lower than that in the control group (P<0.05). The ocular position retraction rate in the VPT group was significantly lower than that in the control group at 12mo (8.89% vs 26.67%, P=0.03). VPT effectively promotes binocular visual function reconstruction in intermittent exotropia children after strabismus surgery and reduces the strabismus severity and ocular position retraction rate.

Effects of alcohol consumption on driving performance in the presence of interocular differences simulated by filters

The role of interocular differences simulated by filters (fog filter and Bangerter foil) on visual and driving performance in alcohol users was assessed. We found that the binocular visual function deteriorates significantly in terms of contrast sensitivity (from 6 to 18 cpd). Additionally, driving performance is significantly impaired under these conditions as evidenced by increased mean speed, standard deviation of the lateral position, distance traveled outside the lane, reaction time and number of collisions. Furthermore, we found that interocular differences due to intraocular scattering and straylight are directly related to an overall reduction in visual and driving performance. This provided a comprehensive perspective from which to understand the relationship between binocular visual function, interocular differences, and driving performance. In practice, our findings contribute to the understanding of the importance of limiting interocular differences, which can be common among presbyopes corrected using the monovision technique, as well as in cases of cataract or other ocular pathology affecting only one eye, or even in cases of cataract surgery of the first eye. These interocular differences can have an adverse impact on road safety, especially when combined with moderate alcohol consumption.

Measurements of Binocular Visual Function and Reading Ability in Induced Aniseikonia

Measurements of Binocular Visual Function and Reading Ability in Induced Aniseikonia

Changes in saccadic eye movement and smooth pursuit gain in patients with acquired comitant esotropia after strabismus surgery.

This study investigates the change in horizontal saccadic eye movement and smooth pursuit in patients with acquired comitant esotropia (ACE), before and after strabismus surgery. The horizontal saccades and pursuit in 11 patients with ACE were recorded using a video eye-tracker under binocular viewing before and after strabismus surgery. Participants were instructed to fixate on the new target as rapidly as possible when it randomly appeared at either 18.3° rightward or 18.3° leftward. For smooth pursuit, participants were asked to track, as accurately as possible, a step-ramp target moving at ±6.1°/s. The asymmetry of adduction-abduction and the binocular coordination in gains of saccade and pursuit were compared between the pre- and post-surgical data. The asymmetry of adduction-abduction saccade gain in each eye after surgery tended to be smaller than that before surgery. The binocular coordination of saccade showed significant improvement after surgery in only the non-dominant eye direction. Adduction-abduction asymmetry in the smooth pursuit gain in each eye after surgery tended to be smaller than before surgery. After surgery, the binocular coordination of pursuit was improved significantly in both directions. In patients with ACE, binocular coordination of saccade and smooth pursuit was poor. Binocular coordination of saccade and pursuit seems to be improved due to the improvement in ocular deviation angle and binocular visual function after surgery.

Comparison of binocular visual quality in six treatment protocols for bilateral cataract surgery with presbyopia correction: a prospective two-center single-blinded cohort study

Objective To compare the postoperative binocular visual quality in six treatment protocols for bilateral age-related cataract surgery with presbyopia correction for clinical decisions. Materials and methods In this prospective two-center single-blinded cohort study, participants from North or South China who underwent bilateral phacoemulsification and intraocular lens implantation were divided into six protocols: monovision, diffractive bifocal, mixed, refractive bifocal, trifocal, and micro-monovision extended range of vision (EROV). Binocular visual quality was evaluated at 3 months postoperatively, including binocular uncorrected full-range visual acuity, binocular defocus curves (depth of focus [DoF] and area under the curve [AUC]), binocular visual function (fusion function and stereopsis), binocular subjective spectacle independence rates, visual analog scale (VAS) of overall satisfaction, 25-item visual function questionnaire (VFQ-25), and binocular dysphotopsia symptoms. Results Of the 300 enrolled patients, 272 (90.7%; 544 eyes) were analyzed. The trifocal protocol showed excellent binocular full-range visual acuity and the best performance for most DoFs and AUCs. The monovision protocol presented the worst binocular visual quality in most perspectives, especially in convergence, distance, and near stereopsis (p < 0.001). The full-range subjective spectacle independence rates were sorted from highest to lowest as follows: trifocal (84.8%), refractive bifocal (80.9%), EROV (80.0%), mixed (73.3%), diffractive bifocal (65.2%), and monovision (32.6%) protocols, with no statistically significant differences between the former five protocols (p > 0.05). The EROV protocol achieved the highest VAS and VFQ-25 scores. The incidence of postoperative binocular dysphotopsia symptoms was comparable in all protocols. Conclusions The trifocal protocol showed the best performance, and the monovision protocol presented the worst performance in most perspectives of binocular visual quality for presbyopia correction. The refractive bifocal, mixed, or EROV protocols can provide an approximate performance as a trifocal protocol. Ophthalmologists can customize therapies using different protocols.

Monocular and Binocular Visual Function Assessments and Activities of Daily Living Performance in Age-Related Macular Degeneration

To evaluate the relationship between specific monocular and binocular visual function (VF) assessments with binocularly performed activities of daily living task tests (ADLTTs) in patients with age-related macular degeneration (AMD) and healthy controls. Prospective case-control cohort study. Thirty-six AMD patients and 36 controls. Visual field assessments included monocular and binocular best-corrected visual acuity (BCVA), contrast sensitivity (CS), and monocular microperimetry testing for mean macula sensitivity, mean retina sensitivity (MRS), fixation area, and fixation distance from fovea (FDF). Age-related macular degeneration lesion area and sensitivity were measured on OCT and microperimetry, respectively. Participants performed 4 validated ADLTTs with binocular BCVA: (1) reading; (2) item-search; (3) money-counting; and (4) multi-step drink-making tasks. Spearman correlations and multivariate regression analysis, adjusted for age, sex, and potential correlation between the 2 eyes, were used to assess the relationship between monocular and binocular VF assessments, and ADLTT performance in both groups. Age-related macular degeneration patients had poorer VF (BCVA, CS, mean macula sensitivity, and MRS) compared with healthy controls. Monocular BCVA in both better- and worse-vision eyes was moderately correlated with the binocular reading speed and money-counting tasks in participants with AMD. In AMD, monocular worse eye CS, MRS, AMD lesion area on OCT, and lesion sensitivity on microperimetry showed moderate correlations to various ADLTTs, such as reading, money-counting, and drink-making. Similar findings were found in our AMD cohort on multivariate regression analysis. Fewer significant correlations were observed for the better-vision eye, whereas no correlations were observed for healthy controls between VF parameters and ADLTTs. In contrast, significant associations were observed between binocular BCVA and CS with binocular ADLTTs (reading and item-search tasks) but not in AMD patients. Although monocular BCVA remains the most common measure of VF, CS and microperimetry testing also show significant correlations with ADLTTs performance in AMD patients, and should be considered as complimentary VF-outcome measures in both clinical and research settings. Unlike healthy subjects, AMD patients do not rely on binocular VF for ADLTT function, with the worse-vision eye impacting binocular ADLTT function more than the better-vision eye. Therefore, the worse-vision eye should not be neglected during the management of AMD. Proprietary or commercial disclosure may be found after the references.

Unilateral visual impairment: impact on binocular function of school children in rural communities of Saki-East, Southwest Nigeria

PurposeThis study was designed to determine the impact of unilateral visual impairment or blindness on binocular visual function in children. MethodsA multistage, cross-sectional study was conducted among primary and secondary school students in the Saki-East Local Government Area of Oyo State between May and July 2021. Unilateral visual impairment was defined as presenting visual acuity <+0.3 LogMAR. Stereopsis, contrast sensitivity and peripheral visual fields were assessed with the Titmus fly test chart, Mars Contrast sensitivity chart and Lister perimeter respectively. Chi-squared test and Logistic regression were performed to assess the association between the degree of unilateral visual impairment and the other independent variables. ResultsFifty-one of 3671 (1.4%) children had unilateral visual impairment or blindness. The mean age was 10.7 ± 3.6 years. Stereopsis was weak or absent in 38 (74.5%) participants, contrast sensitivity values were impaired in 50 (98%) participants, and 29 (61.7%) participants had constricted peripheral visual fields. The level of stereopsis of participants worsened with increasing severity of the unilateral visual impairment, and this was statistically significant (p < 0.001). ConclusionChildren with unilateral visual impairment had poor binocular function. This correlated with stereopsis, worse in participants with severe visual impairment.

Impact of Monocular and Binocular Visual Function Parameters on Vision-Related Quality of Life in Glaucoma.

This study describes the impact of monocular (M/O) and binocular (B/O) visual function decline, primarily the contrast sensitivity (CS) and visual field (VF) defect severity and its location, on the subjective perception of quality of life (QoL) among the Indian glaucoma population with spared central acuity. To investigate the influence of M/O and B/O visual function parameters on vision-related QoL (VRQoL) in glaucoma with spared central visual acuity. Glaucoma subjects underwent M/O and B/O visual acuity, CS assessment, followed by the M/O perimetry from which the integrated VF was estimated (B/O summation method). VRQoL was evaluated using the Glaucoma Quality Of Life-15 (GQL-15) and Visual Function Questionnaire-Utility Index (VFQ-UI) questionnaires. The relationship between CS and VF defect (VFD) with the composite VRQoL scores was analyzed. A total of 154 glaucoma subjects with a median age of 61 (range: 24-83) years were enrolled. Subjects with severe VFD reported poor composite scores for GQL-15 and VFQ-UI when compared with unilateral and mild groups ( P < 0.001, Dunn post hoc). Both the composite scores were negatively correlated with M/O and B/O CS and VF mean deviation ( r range: -0.3 to -0.5, P < 0.001, Spearman rank correlation). B/O VFD in the inferior central zone contributed to poor GQL-15 score [odds ratio: 1.14 (95% CI: 1.10-1.29), P = 0.04] irrespective of sex, whereas females with increasing B/O VFD reported poor QoL score in VFQ-UI [odds ratio: 4.09 (95% CI: 1.77-9.43), p=0.003]. Poor GQL-15 and VFQ-UI scores were reported with increasing disease severity. B/O VFD in the inferior central region was found to contribute predominantly to the poor GQL-15 scores while both disease severity and sex influenced VFQ-UI scores.

Korean Versions of the Reading Test and Visual Perception Test for Children Treated for Unilateral Amblyopia

Purpose: Reading speed and visual perception are used to evaluate visual function in children with amblyopia. This study used standardized tests to evaluate binocular reading performance and visual motor function in children treated for unilateral refractive amblyopia.Methods: In a prospective pilot study, reading and visual perception were evaluated in children aged 5-12 years who were diagnosed with unilateral refractive amblyopia between September 2020 and March 2021. To evaluate reading skills, the Readability Diagnostic Assessment and Korean Language-based Reading Assessment (KOLRA) were administered. The Korean version of the Developmental Test of Visual Perception-Third Edition (K-DTVP-3) test was used to evaluate visual perception function.Results: Reading ability and visual perception function were evaluated in 10 patients with unilateral refractive amblyopia. In the reading fluency test, the average reading speed of the patients was 185 ± 78.2 words per minute (WPM), and did not differ from that of the control group provided by KOLRA (p &gt; 0.05). The general visual perception score was not significantly different from that of the controls. Among subtests of the K-DTVP-3, the hand coordination and figure-background tests scored 32.3 ± 17.7% and 29.9 ± 18.7%, respectively, lower than 50% of the normal average. The scores of the eye-hand coordination (r2 = 0.585, p = 0.01) and figure-background (r2 = 0.482, p = 0.03) tests were significantly correlated with the subject’s best-corrected visual acuity.Conclusions: In this study, there was no significant difference in reading fluency between the patients and controls. Among the K-DTVP-3 subtests, the average scores of the hand coordination and figure-background tests were lower than normal. Further studies are required to determine whether the reading fluency test and K-DTVP-3 reflect visual perception deficits in amblyopic patients.

Clinical observation of bow-tie adjustable suture technique for overcorrection in intermittent exotropia

Objective: To investigate the clinical effects of the bow-tie adjustable suture technique in managing overcorrection in patients with intermittent exotropia after surgery. Methods: This was a retrospective case series study. Clinical data were collected from children with intermittent exotropia who underwent strabismus correction surgery, including the bow-tie adjustable suture technique and conventional techniques, at the Department of Strabismus and Pediatric Ophthalmology, Shanxi Eye Hospital, from January 2020 to September 2021. Children with postoperative esodeviation≥15 prism diopters (PD) within the first 6 days were treated differently based on the surgical technique and their individual conditions, including suture adjustment and conservative treatment. The overcorrection rate and its changes among different surgical groups, the recovery of ocular alignment and binocular visual function after different treatment methods in children with overcorrection on the sixth postoperative day, and the postoperative complications in different surgical groups were observed. Statistical analysis was performed using independent samples t-test, Wilcoxon rank-sum test, repeated-measures analysis of variance, Bonferroni test, chi-square test, or Fisher's exact probability test, as appropriate. Results: A total of 643 children who underwent intermittent exotropia correction surgery were included in the study. Among them, 325 children underwent the bow-tie adjustable suture technique, with 185 males and 140 females, and the mean age was (9.50±2.69) years. The remaining 318 children underwent conventional techniques, with 176 males and 142 females, and the mean age was (9.90±2.67) years. There were no statistically significant differences in age and gender distribution between the two surgical groups (all P>0.05). On the first postoperative day, among children who underwent the bow-tie adjustable suture technique, 40 had an esodeviation of≥10 PD, resulting in an overcorrection rate of 12.3% (40/325), while among children who underwent conventional techniques, 32 had an esodeviation of≥10 PD, resulting in an overcorrection rate of 10.1% (32/318). On the sixth postoperative day, these rates decreased to 5.5% (18/325) and 3.1% (10/318) in the two groups, respectively. At 1, 6, and 12 months postoperatively, the overcorrection rate in children who underwent the bow-tie adjustable suture technique was 0, while in children who underwent conventional techniques, the overcorrection rate did not show a significant decrease compared to before surgery. The differences between the two surgical groups were statistically significant (all P<0.05). On the sixth postoperative day, among children with an esodeviation of≥15 PD, 13 underwent suture adjustment and 7 received conservative treatment. The results of repeated-measures analysis of variance showed statistically significant differences in near and distance esodeviation angles among children who received different treatment methods (F=145.20, 106.87, both P<0.001), as well as statistically significant differences in near and distance esodeviation angles at different time points within each group of children (F=81.67, 35.09, both P<0.001). There were also significant differences in the trends of change in near and distance esodeviation angles at different time points among children who received different treatment methods (F=79.90, 36.73, both P<0.001). Further pairwise comparisons showed significant differences in near and distance esodeviation angles between the sixth postoperative day and 1, 6, and 12 months postoperatively in children who underwent suture adjustment (all P<0.05), while no statistically significant differences were observed in children who received conservative treatment (all P>0.05). At 12 months postoperatively, among the 13 children who underwent suture adjustment, 12 achieved stereopsis, while among the 7 children who received conservative treatment, all became stereo-blind after removing the prismatic correction. No serious complications occurred in any of the children postoperatively. Conclusion: The proportion of children with intermittent exotropia who achieved orthotropic alignment one year after surgery was relatively low among those who had an overcorrection of≥15 PD on the sixth postoperative day. The bow-tie adjustable suture technique is a simple and effective approach for managing overcorrection in patients with intermittent exotropia. Adjusting the sutures on the sixth postoperative day can reduce the overcorrection rate and is considered a safe and effective method.

The diagnostic accuracy of the IFLIP system for binocular visual function anomalies assessment.

This study aimed to evaluate the diagnostic accuracy of the intelligent flipper (IFLIP) system in identifying binocular vision anomalies. This study comprised 70 participants aged 18 to 22. Participants underwent comprehensive eye assessments, including measurement of visual acuity, refraction, far and near cover test, stereopsis, and worth four dot test. The manual accommodation amplitude and facility, as well as the IFLIP system test, were also evaluated. The correlation between the indices of the IFLIP and manual accommodation tests was analyzed using multiple regression models, and the diagnostic ability of the IFLIP was characterized using Receiver Operating Curve (ROC) analysis. The significance level was 0.05. The mean age of the 70 participants was 20.03±0.78 years. The mean manual and IFLIP accommodation facilities were 12.00±3.70 cycle per minute (CPM) and 10.01±2.77 CPM, respectively. No correlation was found between the indices of the IFLIP system and manual accommodative amplitude. However, the regression model showed that the contraction/relaxation ratio of the IFLIP system was positively correlated to the manual accommodation facility, and the average contraction time was negatively correlated with the manual accommodation facility. The ROC analysis proposed a cut-off of 10.15 CPM monocularly for the IFLIP accommodation facility assessment. This study indicated that the parameters obtained by the IFLIP system and the manual accommodation facility were comparable, and the IFLIP system had good sensitivity and specificity in the assessment of the accommodation facility, thus may serve as a promising tool for screening and diagnosis of binocular visual function anomalies in clinical and community settings.

Characteristics of binocular vision and oculomotor function among sports-concussed athletes

Purpose: To compare the binocular vision and oculomotor function between sports-concussed athletes and aged-matched controls. Methods: Thirty mild concussed athletes were recruited and compared with aged-matched controls. All the participants underwent a comprehensive ocular assessment followed by an oculomotor assessment which included tests for accommodation, vergence, eye movements, and reading parameters. Results: Three categories of oculomotor-based deficits were found: convergence insufficiency (40%), accommodative insufficiency (25%), and oculomotor-based reading dysfunctions (20%). A statistically significant reduction in the mean ± SD of the following parameters was noted in concussed athletes v/s controls:- binocular accommodative amplitude: 7.13 ± 1.59 v/s 15.35 ± 2.95 (P &lt; 0.001), convergence amplitude: 14.23 ± 5.00 v/s 5.65 ± 0.90 (P &lt; 0.001), positive fusional vergence for distance: 21.17 ± 8.97 v/s 31.32 ± 6.23 (P &lt; 0.001), vergence facility: 6.47 ± 1.47 v/s 11.84 ± 1.00 (P &lt; 0.001), accommodative facility: 7.10 ± 4.57 v/s 11.67 ± 1.83 (P &lt; 0.001), reading speed: 66.97 ± 17.82 v/s 144.13 ± 24.45 (P = 0.03) and Developmental Eye Movement ratio: 1.40 ± 0.19 v/s 1.17 ± 0.06 (P &lt; 0.001). Conclusion: Concussions caused by sports have a considerable impact on binocular vision and oculomotor parameters. These findings have substantial therapeutic implications in terms of establishing a periodic screening program for athletes so that essential therapy can be provided for a better outcome.

Clinical analysis of eye movement-based data in the medical diagnosis of amblyopia

Amblyopia is an abnormal visual processing-induced developmental disorder of the central nervous system that affects static and dynamic vision, as well as binocular visual function. Currently, changes in static vision in one eye are the gold standard for amblyopia diagnosis. However, there have been few comprehensive analyses of changes in dynamic vision, especially eye movement, among children with amblyopia. Here, we proposed an optimization scheme involving a video eye tracker combined with an "artificial eye" for comprehensive examination of eye movement in children with amblyopia; we sought to improve the diagnostic criteria for amblyopia and provide theoretical support for practical treatment. The resulting eye movement data were used to construct a deep learning approach for diagnostic and predictive applications. Through efforts to manage the uncooperativeness of children with strabismus who could not complete the eye movement assessment, this study quantitatively and objectively assessed the clinical implications of eye movement characteristics in children with amblyopia. Our results indicated that an amblyopic eye is always in a state of adjustment, and thus is not "lazy." Additionally, we found that the eye movement parameters of amblyopic eyes and eyes with normal vision are significantly different. Finally, we identified eye movement parameters that can be used to supplement and optimize the diagnostic criteria for amblyopia, providing a diagnostic basis for evaluation of binocular visual function.

Binocular visual function improvement after pars plana vitrectomy for epiretinal membrane.

To report binocular visual function changes after pars plana vitrectomy for epiretinal membrane (ERM) and the related outcomes. Twenty-three eyes of 23 patients operated on for ERM were included in a retrospective study. Clinical data, best-corrected visual acuity (BCVA), contrast sensitivity and binocular visual function were assessed pre- and 1 and 3 months post-operatively. Binocular visual function assessment included the evaluation of fusional amplitudes (i.e., vergences) by the synoptophore, far distance stereopsis using polarized glasses and near stereopsis using Randot and TNO tests. Central macular thickness (CMT) was measured on Spectral Domain - Optical Coherence Tomography. Mean age of the patients was 67 years. Mean BCVA and contrast sensitivity significantly improved post-operatively at one (p = 0.0006 and p = 0.0022, respectively) and 3 months (p < 0.0001 and p < 0.0001, respectively), while CMT significantly decreased after 1-3 months (p < 0.0001 and p < 0.0001, respectively). Fusional amplitudes improved after 3 months (p < 0.0001). Far distance and near stereopsis significantly improved after 3 months (p < 0.0001 and p = 0.0007 for Randot test, and p < 0.0001 for TNO test, respectively). Pars plana vitrectomy for ERM surgery leads to an improvement of monocular and binocular visual functions (i.e., binocular fusion, near and far distance stereopsis), within 3 months post-operatively.

Enriched binocular experience followed by sleep optimally restores binocular visual cortical responses in a mouse model of amblyopia

Studies of primary visual cortex have furthered our understanding of amblyopia, long-lasting visual impairment caused by imbalanced input from the two eyes during childhood, which is commonly treated by patching the dominant eye. However, the relative impacts of monocular vs. binocular visual experiences on recovery from amblyopia are unclear. Moreover, while sleep promotes visual cortex plasticity following loss of input from one eye, its role in recovering binocular visual function is unknown. Using monocular deprivation in juvenile male mice to model amblyopia, we compared recovery of cortical neurons’ visual responses after identical-duration, identical-quality binocular or monocular visual experiences. We demonstrate that binocular experience is quantitatively superior in restoring binocular responses in visual cortex neurons. However, this recovery was seen only in freely-sleeping mice; post-experience sleep deprivation prevented functional recovery. Thus, both binocular visual experience and subsequent sleep help to optimally renormalize bV1 responses in a mouse model of amblyopia.

The Effects of Binocular Visual Function Training after Concomitant Exotropia Surgery

Purpose This study investigated the effect and long-term efficacy of binocular visual function training after concomitant exotropia surgery. Methods A total of 92 patients who underwent concomitant exotropia surgery were randomly divided into group A (the training group) (n = 54), who received binocular four-dimensional (4D) visual function training after surgery, and group B (control group) (n = 38). The patients in group A received personalized 4D visual function training 2 weeks after surgery and were followed up for 12 months. The eye position, distant and near stereo acuity, respectively, and postoperative efficacy were compared with those of the patients in group B. Results The normal eye position rate in group A was higher than in group B at the end of the overall follow-up period (p < .05), and the near stereo acuity rate was higher than the distant stereo acuity rate in both groups A and B at 2 weeks after surgery and at the end of follow up. The distant and near stereo acuity rates of the patients in group A were higher than those in group B (p < .05) at the end of the follow-up period, and the distant stereo acuity of group A was significantly improved (p < .05). The functional complete and incomplete response rates of group A were significantly higher than those of group B at the end of the follow-up period (p < .05). Conclusions Four-dimensional visual function training for patients after concomitant exotropia surgery could facilitate the recovery of postoperative binocular visual function, as well as prevent the recurrence of exotropia after surgery.