Self-perception in Children Aged 3 to 7 Years With Amblyopia and Its Association With Deficits in Vision and Fine Motor Skills

Leveraging neural plasticity for the treatment of amblyopia

Amblyopia is a form of visual cortical impairment that arises from abnormal visual experience early in life. Most often, amblyopia is a unilateral visual impairment that can develop as a result of strabismus, anisometropia, or a combination of these conditions that result in discordant binocular experience. Characterized by reduced visual acuity and impaired binocular function, amblyopia places a substantial burden on the developing child. Although frontline treatment with glasses and patching can improve visual acuity, residual amblyopia remains for most children. Newer binocular-based therapies can elicit rapid recovery of visual acuity and may also improve stereoacuity in some children. Nevertheless, for both treatment modalities full recovery is elusive, recurrence of amblyopia is common, and improvements are negligible when treatment is administered at older ages. Insights derived from animal models about the factors that govern neural plasticity have been leveraged to develop innovative treatments for amblyopia. These novel therapies exhibit efficacy to promote recovery, and some are effective even at ages when conventional treatments fail to yield benefit. Approaches for enhancing visual system plasticity and promoting recovery from amblyopia include altering the balance between excitatory and inhibitory mechanisms, reversing the accumulation of proteins that inhibit plasticity, and harnessing the principles of metaplasticity. Although these therapies have exhibited promising results in animal models, their safety and ability to remediate amblyopia need to be evaluated in humans.

Fine visuomotor skills in amblyopia: a systematic review and meta-analysis

BACKGROUND

Amblyopia is characterised by reduced visual acuity, poor binocular sensory fusion, and impaired or absent stereoacuity. Understanding the extent to which amblyopia affects everyday task performance is important to quantifying the disease burden of amblyopia and can assist clinicians to understand patients' likely functional capability.

METHODS

A systematic literature search identified published studies comparing fine visuomotor performance in either children or adults with amblyopia and those with normal binocular vision. The included studies (22 studies involving 835 amblyopes and 561 controls) reported results of self-perception patient reported outcome measures, tests of motor proficiency and video recorded reaching and grasping. The outcomes of 17 studies were grouped into four meta-analyses, with pooled results reported as standardised mean difference (SMD) with corresponding 95% CI.

RESULTS

Regardless of the cause of amblyopia (anisometropia, strabismus, mixed, deprivation), significant reduction in self-perception of physical competence and athletic competence (SMD=-0.74, 95% CI -1.23 to -0.25, p=0.003); fine motor skills scores (SMD=-0.86, 95% CI -1.27 to -0.45, p<0.0001); speed of visually guided reaching and grasping movements (SMD=0.86, 95% CI 0.65 to 1.08, p<0.00001); and precision of temporal eye-hand coordination (SMD=0.75, 95% CI 0.26 to 1.25, p=0.003) occurred in amblyopes compared with those with normal visual development.

CONCLUSION

Reports of the impact of amblyopia on fine motor skills performance find poorer outcomes in participants with amblyopia compared with those with normal vision development. Consistency in the outcome measure used to assess the functional impact of amblyopia would be valuable for future studies.

The associations of self-perception, movement competence, and clinical features of young school-aged children with glaucoma

The purpose of the study was to determine the associations of self-perception, motor skills, and clinical features of young school-age children with glaucoma (CG). This is a cross-sectional observational study. Children from preschool to second grade, including CG (N = 19), children with amblyopia (CA, N = 28), and controls (N = 32), completed the Manual Dexterity and Aiming and Catching Scales of the Movement Assessment Battery for Children-2nd edition (MABC-2), including Manual Dexterity, Aiming and Catching, and Balance. CG, CA, and their parent completed the Pictorial Scale of Perceived Competence and Social Acceptance for Young Children, respectively, assessing the child's cognitive competence, peer acceptance, physical competence, and maternal acceptance. The Kruskal-Wallis H test and Bonferroni post hoc test compared motor skills among groups. Spearman's correlation analysis evaluated the correlations between motor skills, self-perception, and clinical features. The CG reported lower peer acceptance than CA (P = 0.040), and the parents of CG reported lower cognitive competence than CG reported (P = 0.046). Compared with controls, CG had worse performance of Aiming and Catching, and Balance (P = 0.018 and P = 0.001), and CA had worse performance of Balance (P = 0.009). The motor skills were comparable between CG and CA. For CG, older age correlated with worse competence of Aiming and Catching (r =  - 0.620, P = 0.005), better best-corrected visual acuity of better-seeing eye correlated with higher competence of Manual Dexterity and Balance (r =  - 0.494, P = 0.032, and r =  - 0.516, P = 0.024), and longer duration of glaucoma correlated with worse competence of Manual Dexterity (r =  - 0.487, P = 0.034).

CONCLUSION

 Glaucoma and amblyopia have significant negative impacts on children's daily motor skills. The acuity of a better-seeing eye is an important factor influencing motor movement.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, ChiCTR2100050415.

WHAT IS KNOWN

• The state of mental health in early childhood influences the development of their future personality and physical development. The prognosis and management of glaucoma may seriously impair the mental health development of the affected children. However, the exploration of psychological aspects and motor movement of childhood glaucoma was limited.

WHAT IS NEW

• Children with glaucoma have impaired motor skills and self-perception development, especially in terms of peer socialization.

Clinical profile of amblyopia in a tertiary care facility without proper vision screening in Saudi Arabia

PURPOSE

To evaluate the clinical profile of amblyopia among patients referred to a tertiary care facility in Saudi Arabia.

METHODS

All patients between 1 and 14 years presenting to the amblyopia clinic from 2016 to 2020 were retrospectively reviewed. Amblyopia was defined as visual acuity <0.2 LogMAR (20/30) in the worse eye or two-line difference between the two eyes. We classified patients into strabismic, refractive, mixed strabismic, and refractive and deprivation amblyopia. We subclassified our cohort according to age (< and ≥5 years).

RESULTS

Three hundred and eighty-three patients (199 male 54%) were seen in our clinic. Seventeen patients were excluded because they did not meet our inclusion criteria. The mean age at presentation was 5.05 ± 2.49 years. Strabismic amblyopia was found in 180 (49%), refractive in 101 (27.6%), mixed in 69 (19%), and deprivation in 16 (4.2%). Anisometropia in 85.25% and isometropia in 14.75%. Hyperopic astigmatism was the most common refractive error in 246 (67.2%). Esotropia was the most common deviation (90%). Strabismic amblyopia was significantly higher in the <5 years group (62.4% vs. 36.7%). While refractive amblyopia was significantly higher in ≥5 years group (38.8% vs. 15.7%) (P < 0.001).

CONCLUSION

Strabismic amblyopia was the most commonly diagnosed in our cohort, especially among patients <5 years of age. Refractive amblyopia was more common in older patients and may be under-detected due to the lack of proper vision screening. The implementation of proper vision screening should help in early detection and successful treatment at an early age.

Amblyopia-A novel virtual round table to explore the caregiver perspective

PURPOSE

A survey aimed to capture the caregiver's perspective on the impact of amblyopia and its treatment on the child and family, as well as caregivers' views on the design and feasibility of clinical trials investigating dichoptic binocular therapies for amblyopia.

METHODS

Parents of amblyopic children, patient advocates and healthcare professionals took part in a moderated, structured discussion on a novel virtual advisory-board platform.

RESULTS

Seven parents of children with amblyopia, two patient organisation representatives, one ophthalmologist and one optometrist participated in the survey. A total of 645 posts were entered on the platform over a 14-day period in September 2021. There was widespread agreement that the management of amblyopia poses more of a burden on the child and family than the condition itself, with treatment burden accentuated when treatment is unsuccessful. Parents expressed uncertainty and frustration in relation to the duration of patching, success of patching and alternative treatment options, and felt there was inadequate readily available, easy-to-understand information on the condition. Parents reported that a new treatment for amblyopia, such as dichoptic binocular therapy using video games, should be safe, non-invasive and engaging compared with an eye patch. Treating at home, potentially for a shorter treatment duration, and with an entertaining game were the main reasons parents would join a clinical study with this type of novel therapy. However, due to a limited critical period treatment window, parents would feel more comfortable joining a clinical trial if traditional therapies were offered in conjunction with those under investigation.

CONCLUSION

Patient perspectives and the role of caregivers in the acceptance of any interventional treatments are increasingly recognised. Understanding how amblyopia and its treatment impacts a child and family should be an important premise to guide therapy and evaluate treatment value, both in clinical trials and in routine medical practice.

Translating and evaluating the Chinese version of Pediatric Eye Questionnaire (PedEyeQ-CN) for children

OBJECTIVES

To investigate the reliability and validity of Chinese version of the Pediatric Eye Questionnaire (PedEyeQ-CN) by testing ophthalmic patients in China.

METHODS

The PedEyeQ (standard English version) was translated by local researchers. Children were asked to complete the Child section, and their parents the Proxy and Parent sections. 160 children (32 normal controls, 77 with refractive error, 48 with strabismus/amblyopia, 3 with other eye conditions) aged 5-11 years old, and one parent of each child were recruited. Cronbach's α and intraclass correlation coefficient were calculated to examine the reliability and test-retest reliability; the score differences between controls and patients were compared to examine the validity.

RESULTS

The internal consistency (Cronbach's α ≥ 0.76) and test-retest reliability (r > 0.80) of PedEyeQ-CN were robust. Children with eye conditions had lower scores compared with children with normal vision (refractive error: 10 out of 13 domains, P ≤ 0.021; strabismus/amblyopia: all domains, P ≤ 0.015). Children with strabismus/amblyopia had lower scores compared with children with refractive error (two domains, P = 0.048, P = 0.001). Visual acuity was significantly correlated with functional vision (P = 0.005), but not significantly correlated with the eye-related quality of life (ER-QOL).

CONCLUSIONS

The PedEyeQ-CN is a valuable tool for assessing the functional vision and ER-QOL of Chinese children and help us increase our understanding about the impact of eye conditions on children and their families.

Amblyopia and the whole child

Amblyopia is a disorder of neurodevelopment that occurs when there is discordant binocular visual experience during the first years of life. While treatments are effective in improving visual acuity, there are significant individual differences in response to treatment that cannot be attributed solely to difference in adherence. In this considerable variability in response to treatment, we argue that treatment outcomes might be optimized by utilizing deep phenotyping of amblyopic deficits to guide alternative treatment choices. In addition, an understanding of the broader knock-on effects of amblyopia on developing visually-guided skills, self-perception, and quality of life will facilitate a whole person healthcare approach to amblyopia.

Binocular amblyopia treatment improves manual dexterity

PURPOSE

To determine whether deficits in manual dexterity in children with amblyopia improve after binocular amblyopia treatment and whether improvements are related to age at treatment, baseline sensory status, or amount of improvement in sensory status with treatment.

METHODS

Manual dexterity (Movement Assessment Battery for Children-2), visual acuity, fusion, suppression, and stereoacuity were measured at baseline and after 4-8 weeks of binocular amblyopia in 134 children with amblyopia, including 75 children in the "younger group" (aged 3 to <7 years) and 59 in the "older group" (aged 7-10 years), and in 40 age-similar control children.

RESULTS

Baseline manual dexterity standard scores of amblyopic children were significantly below those of controls in both the younger (8.81 ± 0.33 vs 11.80 ± 0.60 [P < 0.0001]) and older groups (7.19 ± 0.34 vs 9.75 ± 0.57 [P = 0.00013]). After 4-8 weeks of binocular amblyopia treatment, the younger group standard score improved to 9.85 ± 0.35 and the older group improved to 8.08 ± 0.39, but both groups remained significantly lower than controls (P = 0.03 and P = 0.01, resp.). Improvement in manual dexterity standard score was not associated with any baseline factors but was weakly correlated with the amount of visual acuity improvement (rs = 0.26; 95% CI, 0.09-0.41) CONCLUSIONS: Manual dexterity impairments are common among children with amblyopia. In our study cohort, binocular amblyopia treatment improved visual acuity and manual dexterity.

Amblyopia: A review of unmet needs, current treatment options, and emerging therapies

Amblyopia is a global public health issue with extensive, multifaceted impacts on vision and quality of life (QoL) for both patients and families. Geographical variation exists in the management of amblyopia, with traditional mainstay treatments, optical correction, and fellow eye occlusion most successful when implemented at an early age. In recent years, however, studies demonstrating meaningful improvements in older children and adults have challenged the concept of a complete loss of visual processing plasticity beyond the critical period of visual development, with growing evidence supporting the potential efficacy of emerging, more engaging, binocular therapies in both adults and children. Binocular approaches aim to restore deficits in amblyopia that extend beyond monocular visual acuity impairment, including binocular fusion and visuomotor skills. In view of this, incorporating outcome measures that evaluate the visual performance and functional ability of individuals with amblyopia will provide a clearer understanding of the effect of amblyopia on QoL and a more comprehensive evaluation of amblyopia therapies.

Visual system and motor development in children: a systematic review

PURPOSE

The aim of this study was to review the available scientific literature on the possible relationship between the visual system and motor development in children.

METHODS

This study was performed according to the Preferred Reporting Items for Systematic Reviews (PRISMA) statement recommendations. The review protocol is available in PROSPERO (CRD42021245341). Four different databases, namely Scopus, PubMed, CINAHL and Web of Science, were assessed from April 2005 to February 2021. To determine the quality of the articles, we used the Critical Appraisal Skills Programme (CASP) Quality Appraisal Scale, and a protocol was followed to define the levels of evidence on the basis of the Centre for Evidence-Based Medicine Levels of Evidence. The search strategy included terms describing motor development in children and adolescents with visual disorders.

RESULTS

Among the identified studies, 23 were included in the study. All selected articles examined the relationship between the visual system and development in children. The quality of most of the studies was moderate-high, and they were between evidence levels 2 and 4.

CONCLUSIONS

Our systematic review revealed that all included studies established a relationship between the visual system and development in children. However, the methods for measuring the visual system and motor skills lacked uniformity.

Dichoptic and Monocular Visual Acuity in Amblyopia

PURPOSE

Standard-of-care assessment for children with amblyopia includes measuring amblyopic eye best-corrected visual acuity (AE BCVA) with the fellow eye occluded. By definition, this abolishes the interocular suppression fundamental to amblyopia. Thus, measured AE BCVA may not accurately represent that eye's contribution to natural binocular viewing. We compared dichoptic and monocular AE BCVA and examined whether any differences were associated with eye-hand coordination or reading speed.

DESIGN

Cross-sectional study.

METHODS

Dichoptic and monocular AE BCVA of children aged 6-12 years (42 with amblyopia, 24 with recovered normal AE BCVA, 30 control) were measured. Stereoacuity, suppression, eye-hand coordination, and reading speed were also assessed.

RESULTS

Overall, 81% of amblyopic children had worse dichoptic than monocular AE BCVA (mean difference=0.15±0.11 logMAR; P < .0001), and 71% of children with recovered normal AE BCVA had worse dichoptic than monocular AE BCVA (mean difference = 0.20±0.17 logMAR, P < .0001). Controls had no significant difference. The difference between dichoptic and monocular AE BCVA was correlated with performance in standardized aiming/catching (r = -0.48, 95% CI -0.72, -0.14) and manual dexterity tasks (r = -0.37, 95% CI -0.62, -0.06), and with reading speed (r = -0.38, 95% CI -0.65, -0.03).

CONCLUSIONS

Dichoptic AE BCVA deficits were worse than monocular AE BCVA deficits and were associated with reduced stereoacuity and suppression, consistent with the hypothesis that binocular dysfunction plays a role. Further, impaired eye-hand coordination and slow reading were associated with dichoptic, but not monocular, AE BCVA. Some children with amblyopia may benefit from extra time for school tasks requiring eye-hand coordination or reading.

Amblyopia is associated with impaired balance in 3–6-year-old children in China

Purpose

School-age children in China have more advanced motor development than their North American counterparts. This is likely due to cultural differences in children’s regular motor activities. It is unknown whether the motor function impairments associated with binocular visual disorders (BVDs) such as amblyopia in children raised in North America exist for children raised in China.

Design

Prospective case-control study.

Methods

A major tertiary eye hospital in China tested children aged 3 to <7 (n = 63) belonging to three groups: anisometropic or strabismic amblyopia (n = 22), anisometropia or strabismus without amblyopia (n = 20), or controls (n = 21). The main outcome measure was motor function scores (Movement Assessment Battery for Children 2nd edition).

Results

Balance scores varied significantly across groups (F_2,61 = 4.2, p = 0.02) with the amblyopia group (mean ± SD: 12.5 ± 3.0) exhibiting significantly poorer scores than controls (14.8 ± 2.3). The no-amblyopia BVD group (12.8 ± 3.1) did not differ significantly from the other groups. Manual dexterity, catching and throwing and total scores did not vary significantly across the three groups. A separate pre-planned comparison of only the amblyopia and control groups revealed significantly poorer total motor scores in the amblyopia group (10.1 ± 3.2) vs. controls (12 ± 2.4). A linear regression model was unable to significantly predict associations between total motor score and binocular function score (standardized β = −0.09, 95%, p = 0.7), amblyopia etiology (standardized β = 0.14, 95%, p = 0.4), or inter-ocular acuity difference (standardized β = −0.18, 95%, p = 0.4), in the amblyopia group.

Conclusion

Amblyopia is associated with motor function impairment in children raised in China. Motor deficits that may impact everyday activities have been observed in patients with amblyopia across multiple cultures.

Issues Revisited: Shifts in Binocular Balance Depend on the Deprivation Duration in Normal and Amblyopic Adults

INTRODUCTION

Recent studies indicate that short-term monocular deprivation increases the deprived eye's contribution to binocular fusion in both adults with normal vision and amblyopia. In this study, we investigated whether the changes in visual plasticity depended on the duration of deprivation in normal and amblyopic adults.

METHODS

Twelve anisometropia amblyopic observers (aged 24.8 ± 2.3 years) and 12 age-matched normal observers (aged 23.9 ± 1.2 years) participated in the study. The non-dominant eye of normal observers or amblyopic eye of amblyopic observers was deprived for 30, 120, and 300 min in a randomized order. Their eye balance was measured with a phase combination task, which is a psychophysical test, before and after the deprivation. This design enabled us to measure changes induced in binocular balance as an index visual plasticity due to monocular deprivations.

RESULTS

By comparing the ocular dominance changes as a result of monocular deprivation with different deprivation durations, we found evidence that the ocular dominance changes are slightly larger after longer deprivations in both normal and amblyopic observers, albeit with a statistical significance. The changes from 120-min were significantly greater than those from 30-min deprivation in both groups. The magnitude of changes in sensory eye balance was significantly larger in normal observers than that in the amblyopic observers; however, the longevity of changes in visual plasticity was found to be more long-lasting in amblyopic observers than the normal counterparts.

CONCLUSIONS

The duration of deprivation matters in both normal and amblyopic observers. Ocular dominance imbalance that is typically observed in amblyopia can be more ameliorated with a longer duration of deprivation.

Modulation of mean luminance improves binocular balance across spatial frequencies in amblyopia

Amblyopia is a visual impairment that perturbs binocular balance at high spatial frequencies in favor of the fellow eye. Studies reveal that amblyopes who had been treated with monocular therapies still show imbalance. Binocular balance is achieved when both eyes’ inputs are weighed equally. A reduced light can diminish the dimmed eye's weight in binocular combination. In this study, we examined if binocular balance across spatial frequencies could be improved by reducing the luminance of the fellow eye in adult amblyopes. By doing so, we relieved their binocular imbalance across spatial frequencies. Also, normal observers showed amblyopic binocular imbalance when the dominant eye’s light level was dimmed. Therefore, reducing the luminance in the unaffected eye in amblyopia mitigated the binocular imbalance, whereas doing so in normal adults simulated the amblyopic imbalance across spatial frequencies.

•

Binocular balance is impaired in amblyopia

•

Reduced luminance of the fellow eye can improve it across spatial frequencies in amblyopia

•

Reduced luminance of one eye from normal observers simulates amblyopic imbalance

The Orientation Selectivity of Dichoptic Masking Suppression is Contrast Dependent in Amblyopia

Purpose

We aimed to study the effect of stimulus contrast on the orientation selectivity of interocular interaction in amblyopia using a dichoptic masking paradigm.

Methods

Eight adults with anisometropic or mixed amblyopia and 10 control adults participated in our study. The contrast threshold in discriminating a target Gabor in the tested eye was measured with mean luminance in the untested eye, as well as with a bandpass oriented filtered noise in the other eye at low spatial frequency (0.25 c/d). Threshold elevation, which represents interocular suppression, was assessed using a the dichoptic masking paradigm (i.e. the contrast threshold difference between the target only and masked conditions), for each eye. Orientation selectivity of the interocular suppression as reflected by dichoptic masking was quantified by the difference between the parallel and orthogonal masking configurations. Two levels of mask's contrast (3 times or 10 times that of an individual's contrast threshold) were tested in this study.

Results

The strength of dichoptic masking suppression was stronger at high, rather than low mask contrast in both amblyopic and control subjects. Normal controls showed orientation-dependent dichoptic masking suppression both under high and low contrast levels. However, amblyopes showed orientation-tuned dichoptic masking suppression only under the high contrast level, but untuned under the low contrast level.

Conclusions

We demonstrate that interocular suppression assessed by dichoptic masking is contrast-dependent in amblyopia, being orientation-tuned only at high suprathreshold contrast levels of the mask.

A nationwide cohort study on the risk of ADHD in children with amblyopia mediated by fine motor skill impairment in East Asia

This national administrative investigation of Republic of Korea compared the risk of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorders(ASD) in preschool amblyopic children and identified factors that possibly mediate this association. After propensity score (PS) matching, 7762 amblyopic children and 31,030 non-amblyopic children were included. Amblyopia was associated with ADHD (aOR:1.687; 95% CI 1.444, 1.970) but not with ASD (aOR: 0.591; 95% CI 0.341, 1.026). Fine motor skill impairment was a mediating factor in association of amblyopia with ADHD, accounting for 4.2% (95% CI 1.7, 8.0). In conclusion, amblyopic children have a greater risk of ADHD, and deficits in fine motor skills mediate this association. We suggest increased attention given to fine motor skill underdevelopment in amblyopic children to prevent the development of ADHD.

Binocular versus standard occlusion or blurring treatment for unilateral amblyopia in children aged three to eight years

BACKGROUND

Current treatments for amblyopia, typically patching or pharmacological blurring, have limited success. Less than two-thirds of children achieve good acuity of 0.20 logMAR in the amblyopic eye, with limited improvement of stereopsis, and poor adherence to treatment. A new approach, based on presentation of movies or computer games separately to each eye, may yield better results and improve adherence. These treatments aim to balance the input of visual information from each eye to the brain.  OBJECTIVES: To determine whether binocular treatments in children, aged three to eight years, with unilateral amblyopia result in better visual outcomes than conventional patching or pharmacological blurring treatment.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), MEDLINE, Embase, ISRCTN, ClinicalTrials.gov, and the WHO ICTRP to 19 November 2020, with no language restrictions.

SELECTION CRITERIA

Two review authors independently screened the results of the search for relevant studies. We included randomised controlled trials (RCTs) that enrolled children between the ages of three and eight years old with unilateral amblyopia. Amblyopia was classed as present when the best-corrected visual acuity (BCVA) was worse than 0.200 logMAR in the amblyopic eye, with BCVA 0.200 logMAR or better in the fellow eye, in the presence of an amblyogenic risk factor, such as anisometropia, strabismus, or both. To be eligible, children needed to have undergone cycloplegic refraction and  ophthalmic examination, including fundal examination and optical treatment, if indicated, with stable BCVA in the amblyopic eye despite good adherence with wearing glasses. We included any type of binocular viewing intervention, on any device (e.g. computer monitors viewed with liquid-crystal display shutter glasses; hand-held screens, including mobile phones with lenticular prism overlay; or virtual reality displays). Control groups received standard amblyopia treatment, which could include patching or pharmacological blurring of the better-seeing eye. We included full-time (all waking hours) and part-time (between 1 and 12 hours a day) patching regimens. We excluded children who had received any treatment other than optical treatment; and studies with less than 8-week follow-up.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. The primary outcome of the review was the change from baseline of distance BCVA in the amblyopic eye after 16 (± 2) weeks of treatment, measured in logMAR units on an age-appropriate acuity test.

MAIN RESULTS

We identified one eligible RCT of conventional patching treatment versus novel binocular treatment, and analysed a subset of 68 children who fulfilled the age criterion of this review. We obtained data for the mean change in amblyopic eye visual acuity, adverse events (diplopia), and adherence to prescribed treatment at 8- and 16-week follow-up intervals, though no data were available for change in BCVA after 52 weeks. Risk of bias for the included study was considered to be low. The certainty of evidence for the visual acuity outcomes at 8 and 16 weeks of treatment and adherence to the study intervention was rated moderate using the GRADE criteria, downgrading by one level due to imprecision. The certainty of evidence was downgraded by two levels and rated low for the proportion of participants reporting adverse events due to the sample size.  Acuity improved in the amblyopic eye in both the binocular and patching groups following 16 weeks of treatment (improvement of -0.21 logMAR in the binocular group and -0.24 logMAR in the patching group, mean difference (MD) 0.03 logMAR (95% confidence interval (CI) -0.10 to 0.04; 63 children). This difference was non-significant and the improvements in both the binocular and patching groups are also considered clinically similar. Following 8 weeks of treatment, acuity improved in both the binocular and patching groups (improvement of -0.18 logMAR in the patching group compared to -0.16 logMAR improvement in the binocular-treatment group) (MD 0.02, 95% CI -0.04 to 0.08). Again this difference was statistically non-significant, and the differences observed between the patching and binocular groups are also clinically non-significant. No adverse event of permanent diplopia was reported. Adherence was higher in the patching group (47% of participants in the iPad group achieved over 75% compliance compared with 90% of the patching group).  Data were not available for changes in stereopsis nor for contrast sensitivity following treatment.

AUTHORS' CONCLUSIONS

Currently, there is only one RCT that offers evidence of the safety and effectiveness of binocular treatment. The authors are moderately confident that after 16 weeks of treatment, the gain in amblyopic eye acuity with binocular treatment is likely comparable to that of conventional patching treatment. However, due to the limited sample size and lack of long term (52 week) follow-up data, it is not yet possible to draw robust conclusions regarding the overall safety and sustained effectiveness of binocular treatment. Further research, using acknowledged methods of visual acuity and stereoacuity assessment with known reproducibility, is required to inform decisions about the implementation of binocular treatments for amblyopia in clinical practice, and should incorporate longer term follow-up to establish the effectiveness of binocular treatment. Randomised controlled trials should also include outcomes reported by users, adherence to prescribed treatment, and recurrence of amblyopia after cessation of treatment.

Recent Advances in Screening and Treatment for Amblyopia

Amblyopia is the most common cause of monocular visual impairment in children, with a prevalence of 2-3%. Not only is visual acuity reduced in one eye but binocular vision is affected, fellow eye deficits may be present, eye-hand coordination and reading can be affected, and self-perception may be diminished. New technologies for preschool vision screening hold promise for accessible, early, and accurate detection of amblyopia. Together with recent advances in our theoretical understanding of amblyopia and technological advances in amblyopia treatment, we anticipate improved visual outcomes for children affected by this very common eye condition. This article is based on previously conducted studies and does not contain any new studies with human participants or animals performed by any of the authors.

2-year outcomes of ranibizumab versus laser therapy for the treatment of very low birthweight infants with retinopathy of prematurity (RAINBOW extension study): prospective follow-up of an open label, randomised controlled trial

BACKGROUND

Intravitreal injection of vascular endothelial growth factor (VEGF) inhibitors is increasingly used to treat retinopathy of prematurity (ROP) in the absence of evidence about long-term efficacy or safety. In this prespecified interim analysis of the RAINBOW extension study, we aimed to prospectively assess outcomes at age 2 years.

METHODS

RAINBOW was an open-label, randomised trial that compared intravitreal ranibizumab (at 0·1 mg and 0·2 mg doses) with laser therapy for the treatment of ROP in very low birthweight infants (<1500 g). Families of the 201 infants that completed the RAINBOW core study were approached for consent to enter the extension study, which evaluates treatment outcomes prospectively through to 5 years of age. At age 20-28 months corrected for prematurity, participants had ophthalmic, development, and health assessments. The primary outcome was the absence of structural ocular abnormalities; secondary outcomes included vision-related quality of life (reported by parents using the Children's Visual Function Questionnaire), development (assessed with the Mullen Scales of Early Learning), motor function, and health status. Investigator-determined ocular and non-ocular serious and other adverse events were recorded. This study is registered with ClinicalTrials.gov, NCT02640664.

FINDINGS

Between June 16, 2016, and Jan 22, 2018, 180 infants were enrolled in the RAINBOW extension study, and 153 (85%) were evaluated at 20-28 months of age. No child developed new ocular structural abnormalities. Structural abnormalities were present in one (2%) of 56 infants in the ranibizumab 0·2 mg group, one (2%) of 51 infants in the 0·1 mg group, and four (9%) of 44 infants in the laser therapy group. The odds ratio of no structural abnormality was 5·68 (95% CI 0·60-54·0; p=0·10) for ranibizumab 0·2 mg versus laser therapy, 4·82 (0·52-45·0; p=0·14) for ranibizumab 0·1 mg versus laser therapy, and 1·21 (0·07-20; p=0·90) for ranibizumab 0·2 mg vs 0·1 mg. High myopia (-5 dioptres or worse) was less frequent after 0·2 mg ranibizumab (five [5%] of 110 eyes) than with laser therapy (16 [20%] of 82; odds ratio 0·19, 95% CI 0·05-0·69; p=0·012). Composite vision-related quality of life scores seemed higher among the ranibizumab 0·2 mg group (mean 84, 95% CI 80-88) compared with laser therapy (77, 72-83; p=0·063). Mullen Scales T-scores for visual reception, receptive and expressive language were distributed similarly between the three trial groups and there were similar proportions of infants with motor and hearing problems among treatment groups. The proportion of infants with respiratory symptoms and Z scores of standing height, weight, and head circumference were similarly distributed in the treatment groups. There were no adverse events considered by the investigator to be related to the study intervention.

INTERPRETATION

2-year outcomes following ranibizumab 0·2 mg for the treatment of ROP confirm the ocular outcomes of the original RAINBOW trial and show reduced high myopia, with possibly better vision-related quality of life. This treatment did not appear to affect non-ocular infant development.

FUNDING

Novartis Pharma AG.

Efficacy of vision-based treatments for children and teens with amblyopia: a systematic review and meta-analysis of randomised controlled trials

Objective

To identify differences in efficacy between vision-based treatments for improving visual acuity (VA) of the amblyopic eye in persons aged 4-17 years old.

Data sources

Ovid Embase, PubMed (Medline), the Cochrane Library, Vision Cite and Scopus were systematically searched from 1975 to 17 June 2020.

Methods

Two independent reviewers screened search results for randomised controlled trials of vision-based amblyopia treatments that specified change in amblyopic eye VA (logMAR) as the primary outcome measure. Quality was assessed via risk of bias and GRADE (Grading of Recommendations, Assessment, Development, and Evaluations).

Results

Of the 3346 studies identified, 36 were included in a narrative synthesis. A random effects meta-analysis (five studies) compared the efficacy of binocular treatments versus patching: mean difference -0.03 logMAR; 95% CI 0.01 to 0.04 (p<0.001), favouring patching. An exploratory study-level regression (18 studies) showed no statistically significant differences between vision-based treatments and a reference group of 2-5 hours of patching. Age, sample size and pre-randomisation optical treatment were not statistically significantly associated with changes in amblyopic eye acuity. A network meta-analysis (26 studies) comparing vision-based treatments to patching 2-5 hours found one statistically significant comparison, namely, the favouring of a combination of two treatment arms comparing combination and binocular treatments, against patching 2-5 hours: standard mean difference: 2.63; 95% CI 1.18 to 4.09. However, this result was an indirect comparison calculated from a single study. A linear regression analysis (17 studies) found a significant relationship between adherence and effect size, but the model did not completely fit the data: regression coefficient 0.022; 95% CI 0.004 to 0.040 (p=0.02).

Conclusion

We found no clinically relevant differences in treatment efficacy between the treatments included in this review. Adherence to the prescribed hours of treatment varied considerably and may have had an effect on treatment success.

Motor Competence in Children With and Without Ambliopia

The purpose of this study was to assess the motor competence of children with and without amblyopia. Study participants were 165 primary school children, aged 6-9 years, divided into three groups based on their visual acuity with the Snellen chart: (a) non-amblyopia, (b) corrected amblyopia, and (c) non-corrected amblyopia. We assessed the children's motor competence with the Motor Competence Assessment battery (MCA) and their physical activity with the Physical Activity Questionnaire for Older Children (PAQ-C). The non-amblyopia group presented significantly better motor competence on the MCA than either the corrected amblyopia group or the non-corrected amblyopia group; there were no statistically significant motor differences between the two amblyopia subgroups. Amblyopia versus non-amblyopia differences on the MCA were mainly in stability and locomotor components, involving dynamic balance and the change of spatial position and direction of movement, but not in the manipulative component (ball throwing velocity and ball kicking velocity). Predictably, from within an integrated visual motor perspective of child development, our findings suggest that intact vision played an important role in children's motor competence. The development of fundamental motor skills, especially of stability and locomotor skills, may be affected by poor visual processing in that participants with uncorrected amblyopia showed poor movement accuracy, uncoordinated movement, and impaired balance.

Factors Associated with Impaired Motor Skills in Strabismic and Anisometropic Children

Purpose

We evaluated motor skills in children diagnosed with strabismus and anisometropia, with or without amblyopia, and explored factors associated with impairments.

Methods

A total of 143 strabismic and anisometropic children 3 to 13 years of age (96 amblyopic, 47 nonamblyopic) and a group of age-similar 35 control children completed Manual Dexterity, Aiming and Catching, and Balance tasks from the Movement Assessment Battery for Children, Second Edition. Raw scores were converted to standardized scores, and amblyopic and nonamblyopic children were compared to controls. Clinical and sensory factors associated with motor performance were also evaluated.

Results

Overall, amblyopic and nonamblyopic children were three to six times more likely than controls to be at risk for or to have a total motor impairment (≤15th percentile). Although amblyopic children scored lower than controls for the Manual Dexterity, Aiming and Catching, and Balance tasks, nonamblyopic children scored lower on Manual Dexterity only. Factors related to manual dexterity deficits include the presence of amblyopia and binocularity deficits typical of these eye conditions. Aiming, catching, and balance deficits were most pronounced in children with an infantile onset of the eye condition, a history of strabismus, and reduced binocularity.

Conclusions

Amblyopia and strabismus disrupt the development of motor ability in children. These findings highlight the widespread effects of discordant binocular input early in life and the visual acuity and binocularity deficits typical of these eye conditions.

Interocular Suppression as Revealed by Dichoptic Masking Is Orientation-Dependent and Imbalanced in Amblyopia

Purpose

We investigate the orientation tuning of interocular suppression using a dichoptic masking paradigm in adult controls and amblyopes.

Methods

Fourteen adults with anisometropic or mixed amblyopia and 10 control adults participated in our study. Contrast sensitivity was measured by presenting a target Gabor in the tested eye and mean luminance in the untested eye (monocular) and by presenting a target in the tested eye and a bandpass oriented filtered noise in the other eye (masked). Interocular suppression was defined as the thresholds difference between the monocular and masked conditions for each eye. Interocular suppression was measured under parallel and orthogonal suppression configurations. The peak spatial frequency of the target and mask was 0.25 c/d in experiment 1 (low), 1.31 c/d in experiment 2 (mid), and 6.87 c/d in experiment 3 (high).

Results

The masking suppression induced by the amblyopic eye was less strong than that induced by the fellow eye. The suppression from the fellow eye was similar to that observed in the controls. Interocular suppression under parallel configuration was less strong than under orthogonal configuration in amblyopes at low and mid spatial frequency, but not at high spatial frequency.

Conclusions

We demonstrate that the abnormal interocular masking in amblyopia displays the expected characteristic of orientation selectivity expected of normal controls at low and mid spatial frequency, but not at high spatial frequency. The dichoptic masking imbalance between the eyes of amblyopes results in a net suppression of the amblyopic eye during binocular viewing, modeling clinical suppression.

Self-perception in Preschool Children With Deprivation Amblyopia and Its Association With Deficits in Vision and Fine Motor Skills

Importance

Although the development of self-perception and self-esteem has been investigated in children with strabismic and anisometropic amblyopia, we know little about how self-perception is affected in deprivation amblyopia. Deprivation amblyopia from a dense, unilateral cataract is the least common and typically most severe form of amblyopia. After cataract extraction, optical correction, and patching treatment for amblyopia, visual acuity almost always remains abnormal, and except in rare cases, stereoacuity is nearly always nil.

Objective

To determine whether deprivation amblyopia is associated with altered self-perception in preschool children and to determine whether any differences in self-perception are associated with vision or motor skill deficits.

Design, Setting, and Participants

Cross-sectional study conducted from 2016 to 2019 at a pediatric vision research laboratory. Children aged 3 to 6 years were enrolled, including 15 children with deprivation amblyopia and 20 control children.

Main Outcomes and Measures

Self-perception was assessed using the Pictorial Scale of Competence and Acceptance for Young Children, which includes 4 specific domains: cognitive competence, peer acceptance, physical competence, and maternal acceptance. Fine motor skills were evaluated with the Manual Dexterity and Aiming & Catching Scales of the Movement ABC-2 test. Visual acuity and stereoacuity also were assessed.

Results

Of the 35 children included, 13 of 35 were girls (37%) and 28 of 35 were non-Hispanic White (80%). Children with deprivation amblyopia had significantly lower peer acceptance and physical competence scores compared with control children (mean [SD], 2.80 [0.44] vs 3.25 [0.33]; mean difference, 0.45; 95% CI for difference, 0.19-0.71; P = .002 and 2.94 [0.45] vs 3.41 [0.37]; mean difference, 0.47; 95% CI for difference, 0.19-0.75; P = .002, respectively). Among children with amblyopia, moderate associations were found between self-perception domain scores and motor skills, including peer acceptance and manual dexterity (r = 0.68; 95% CI, 0.26-0.89; P = .005), peer acceptance and aiming (r = 0.54; 95% CI, 0.03-0.82; P = .03), and physical competence and aiming (r = 0.55; 95% CI, 0.06-0.83; P = .03).

Conclusions and Relevance

Lower self-perception of peer acceptance and physical competence were associated with early visual deprivation in children in their everyday life.

Amblyopia Outcomes Through Clinical Trials and Practice Measurement: Room for Improvement: The LXXVII Edward Jackson Memorial Lecture

PURPOSE

To describe amblyopia prevalence and outcomes using results from randomized studies and a clinical registry.

DESIGN

Review of published studies, analysis of data in Intelligent Research in Sight (IRIS) Registry from 2013 to 2019, personal perspective.

METHODS

Literature review, analysis of IRIS Registry data and IRIS-50, a visual acuity quality measure.

RESULTS

Clinical trials have reduced the treatment burden of amblyopia by reducing hours of patching and frequency of atropine eye drops with clinical success of about 83%. There is no appreciable age effect if treatment is started before 5 years of age, outcomes are stable to at least 15 years of age, and treatment can be somewhat effective until 12 years of age. The IRIS Registry identified 1,760,066 individuals with amblyopia for a prevalence of 2.47%. Refractive error alone accounted for 68.9% of childhood cases. Mean amblyopic eye visual acuity improved 1.8 lines for children 3-6 years of age and 0.8 lines for 7-12 years, but mean residual amblyopia was more than 2 lines. Among 18,841 children aged 3-7 years eligible for IRIS-50, 77.3% were successful. The odds ratios for success were significantly lower for African-American (0.67; 95% confidence interval [CI] = 0.58 to 0.78) and Hispanic or Latino (0.84; 95% CI = 0.75 to 0.94) children compared with white children.

CONCLUSIONS

Clinical trials provided evidence of a beneficial effect from several treatments, with substantially reduced doses than previously recommended. Registry data from clinical practice found residual visual acuity impairment among all ages and races, especially among minorities.

Understanding the Impact of Residual Amblyopia on Functional Vision and Eye-related Quality of Life Using the PedEyeQ

PURPOSE

To evaluate the effect of residual amblyopia on functional vision and eye-related quality of life (ER-QOL) in children and their families using the Pediatric Eye Questionnaire (PedEyeQ).

DESIGN

Prospective cross-sectional study.

METHODS

Seventeen children with residual amblyopia (no current treatment except glasses), 48 visually normal controls without glasses, and 19 controls wearing glasses (aged 8-11 years) completed the Child 5-11 year PedEyeQ. One parent for each child completed the Proxy 5-11 PedEyeQ, Parent PedEyeQ. Rasch-calibrated domain scores were calculated for each questionnaire domain and compared between amblyopic children and controls.

RESULTS

PedEyeQ scores were significantly lower (worse) for children with residual amblyopia than for controls without glasses across all domains: Child PedEyeQ greatest mean difference 18 points worse on Functional vision domain (95% confidence interval [CI] -29 to -7; P < .001); Proxy PedEyeQ greatest mean difference 31 points worse on Functional vision domain (95% CI -39 to -24; P < .001); Parent PedEyeQ greatest mean difference 34 points worse on the Worry about child's eye condition domain (95% CI -46 to -22; P < .001). Compared with controls wearing glasses, PedEyeQ scores were lower for residual amblyopia on the Child Frustration/worry domain (P = .03), on 4 of 5 Proxy domains (P ≤ .05), and on 3 of 4 Parent domains (P ≤ .05).

CONCLUSIONS

Residual amblyopia affects functional vision and ER-QOL in children. Parents of amblyopic children also experience lower quality of life. These data help broaden our understanding of the everyday-life impact of childhood residual amblyopia.

Associations of Eye-Related Quality of Life With Vision, Visuomotor Function, and Self-Perception in Children With Strabismus and Anisometropia

Purpose

To evaluate associations between eye-related quality of life (ER-QOL) assessed by the Child Pediatric Eye Questionnaire (Child PedEyeQ) and functional measures (vision, visuomotor function, self-perception) in children with strabismus, anisometropia, or both. Our hypothesis was that children with functional deficits would have lower ER-QOL, and if so, these associations would support the convergent construct validity of the Child PedEyeQ.

Methods

We evaluated 114 children (ages 5-11 years) with strabismus, anisometropia, or both. Each child completed the Child PedEyeQ to assess four Rasch-scored domains of ER-QOL: Functional Vision, Bothered by Eyes/Vision, Social, and Frustration/Worry. In addition, children completed one or more functional tests: visual acuity (n = 114), Randot Preschool Stereoacuity (n = 92), contrast balance index (suppression; n = 91), Readalyzer reading (n = 44), vergence instability (n = 50), Movement Assessment Battery for Children-2 manual dexterity (n = 57), and Pictorial Scale of Perceived Competence and Social Acceptance for Young Children (n = 44).

Results

Child PedEyeQ Functional Vision domain scores were correlated with self-perception of physical competence (rs = 0.65; 95% confidence interval [CI], 0.35-0.96) and reading speed (rs = 0.47; 95% CI, 0.16-0.77). Bothered by Eyes/Vision domain scores were correlated with self-perception of physical competence (rs = 0.52; 95% CI, 0.21-0.83). Moderate correlations were observed between Social domain scores and vergence instability (rs = -0.46; 95% CI, -0.76 to -0.15) and self-perception of physical competence (rs = 0.43; 95% CI, 0.12-0.73) and peer acceptance (rs = 0.49; 95% CI, 0.18-0.80). Frustration/Worry domain scores were moderately correlated with self-perception of physical competence (rs = 0.41; 95% CI, 0.10-0.71) and peer acceptance (rs = 0.47; 95% CI, 0.16-0.77).

Conclusions

Strong and moderate correlations were observed between functional measures and Child PedEyeQ domain scores. These associations provide supporting evidence that the Child PedEyeQ has convergent construct validity.

Two Patterns of Interocular Delay Revealed by Spontaneous Motion-in-Depth Pulfrich Phenomenon in Amblyopes with Stereopsis

Purpose

To assess interocular delays in amblyopes with stereopsis and to evaluate the relationship between interocular delays and the clinical characteristics.

Methods

Twenty amblyopes with stereopsis (median, 400 arcseconds) and 20 controls with normal or corrected to normal visual acuity (≤0 logMAR) and normal stereopsis (≤60 arcseconds) participated. Using a rotating cylinder defined by horizontally moving Gabor patches, we produced a spontaneous Pulfrich phenomenon in order to determine the interocular delays, that is, the interocular phase difference at which ambiguous motion in plane was perceived. Two spatial frequencies—a low (0.95 cycles/degree [c/d]) and a medium (2.85 c/d) spatial frequency—were tested.

Results

The absolute interocular delays of the amblyopic group was significantly longer than that of the controls at both low or medium spatial frequencies (P < 0.01). However, the interocular delays was not always in favor of the fellow eye: 35% of the amblyopes (7/20) showed a faster processing of the amblyopic eye than that of the fellow eye at 0.95 c/d and 29.5% (5/17) at 2.85 c/d. No significant correlation was found between interocular delays and the clinical characteristics (e.g., age, treatment history, stereoacuity, and magnitude of anisometropia) in this amblyopic cohort.

Conclusions

The interocular delays in amblyopes with stereopsis might result from either a faster or slower processing of the amblyopic eye relative to the fellow eye. This work provides important additional information for binocular processing of dynamic visual stimuli in amblyopia. However, the special role between this form of interocular delays and patients’ clinical characteristics remains unknown.

Vision Development Differences between Slow and Fast Motor Development in Typical Developing Toddlers: A Cross-Sectional Study

Many studies have established a relationship between visual function and motor development in toddlers. This is the first report to study two-year-olds via an assessment of their visual and motor skills. The purpose of this study is to describe the possible changes that can occur between visual and motor systems in typical developing toddlers. A total of 116 toddlers were included in this observational, descriptive, and cross-sectional study. Their mean age was 29.57 ± 3.45 months. Motor development variables studied were dominant hand/foot; stationary, locomotion, object manipulation, grasping, visual motor integration percentiles; gross motor, fine motor, and total motor percentiles; and gross motor, fine motor, and total motor quotients. Visual development variables were assessed including visual acuity, refractive error, ocular alignment, motor fusion and suppression, ocular motility, and stereopsis. Our findings demonstrated that typical developing toddlers with slow gross motor development had higher exophoria and further near point of convergence values compared to toddlers with fast gross motor development (p < 0.05). No statistically significant differences were found in visual acuity and stereopsis between slow and fast gross motor development toddlers.

Abnormal Monocular and Dichoptic Temporal Synchrony in Adults with Amblyopia

Purpose

We investigate temporal synchrony within one eye and between both eyes in adults with amblyopia.

Methods

Eight adult amblyopes (range, 19.88-27.81 years old; median, 22.86 years old) and 12 age-matched adults with normal vision (range, 21.2-50.30 years old; median, 23.78 years old) participated in the experiment. We showed two pairs of Gaussian blobs flickering at 1 Hz as visual stimuli, one pair with the same temporal phase modulation (i.e., the reference) and another pair with a distinct temporal phase (i.e., the signal). We employed the constant stimuli method to measure the minimum degree of temporal phase (temporal synchrony threshold), at which participants were able to discriminate the signal pair under binocular, monocular, and dichoptic viewing configurations.

Results

The temporal synchrony threshold was different across the six configurations (P = 0.001). There was also an interaction between the configuration and the group (P = 0.004). The synchrony threshold was significantly higher in amblyopes than in controls under the configurations where two pairs of blobs were presented to the amblyopic eye (136.52 ± 50.19 vs. 97.08 ± 22.02 ms, P = 0.027) and where the paired blobs were presented to different eyes (163.15 ± 80.85 vs. 111.61 ± 22.46 ms, P = 0.049). The visual deficits in these two configurations were significantly correlated (r = 0.824, P = 0.012).

Conclusions

The threshold for detecting temporal asynchrony increased when the stimuli were presented only to the amblyopic eye and when they were dichoptically presented to the amblyopic and fellow eyes.

Impaired fine motor skills in children following extraction of a dense congenital or infantile unilateral cataract

PURPOSE

To evaluate fine motor ability in children treated for unilateral congenital or infantile cataract.

METHODS

Twenty-three children 3-13 years of age who were treated for unilateral congenital or infantile cataract and 38 age-similar control children were enrolled. Children completed five fine motor skills tasks (unimanual dexterity, bimanual dexterity, drawing trail, aiming, catching) from the Movement Assessment Battery for Children-2. Raw scores were converted into standardized scores, with higher scores indicating better performance.

RESULTS

Compared with controls, children treated for unilateral cataract scored lower on drawing trail (P = 0.009), aiming (P = 0.009), and catching (P < 0.001) but not on unimanual (P = 0.77) or bimanual dexterity (P = 0.31). Poorer affected eye visual acuity was moderately related to poorer performance for unimanual dexterity (r = -0.47; P = 0.025), bimanual dexterity (r = -0.50; P = 0.014), and catching (r = -0.41; P = 0.051). Those with a poor visual outcome (>0.6 logMAR) had worse performance than those with a good visual outcome (≤0.6 logMAR) for all tasks (all P values, 0.008-0.09) except aiming. Cataract type (congenital, 9; infantile, 14) and sensory fusion by Worth 4-Dot testing at 33 cm (pass, 10; fail, 13) had no effect on fine motor performance (all P values, 0.12-0.98).

CONCLUSIONS

In our study cohort, fine motor deficits were found in children treated for congenital or infantile unilateral cataract.

Binocular amblyopia treatment with contrast-rebalanced movies

BACKGROUND

Binocular amblyopia treatments promote visual acuity recovery and binocularity by rebalancing the signal strength of dichoptic images. Most require active participation by the amblyopic child to play a game or perform a repetitive visual task. The purpose of this study was to investigate a passive form of binocular treatment with contrast-rebalanced dichoptic movies.

METHODS

A total of 27 amblyopic children, 4-10 years of age, wore polarized glasses to watch 6 contrast-rebalanced dichoptic movies on a passive 3D display during a 2-week period. Amblyopic eye contrast was 100%; fellow eye contrast was initially set to a lower level (20%-60%), which allowed the child to overcome suppression and use binocular vision. Fellow eye contrast was incremented by 10% for each subsequent movie. Best-corrected visual acuity, random dot stereoacuity, and interocular suppression were measured at baseline and at 2 weeks.

RESULTS

Amblyopic eye best-corrected visual acuity improved from 0.57 ± 0.22 at baseline to 0.42 ± 0.23 logMAR (t26 = 8.09; P < 0.0001; 95% CI for improvement, 0.11-0.19 logMAR). Children aged 3-6 years had more improvement (0.21 ± 0.11 logMAR) than children aged 7-10 years (0.11 ± 0.06 logMAR; t25 = 3.05; P = 0.005). Children with severe amblyopia (≥0.7 logMAR) at baseline experienced greater improvement (0.24 ± 0.12 logMAR) than children with moderate amblyopia at baseline (0.12 ± 0.06 logMAR; t25 = 3.49; P = 0.002).

CONCLUSIONS

In this cohort, passive viewing of contrast-rebalanced dichoptic movies effectively improved visual acuity in amblyopic subjects. The degree of improvement observed was similar to that previously reported for 2 weeks of binocular games treatment and with 3-4 months of occlusion therapy.