Amblyopia and quality of life: a systematic review

Decreased scene-selective activity within the posterior intraparietal cortex in amblyopic adults

Amblyopia is a developmental disorder associated with reduced performance in visually guided tasks, including binocular navigation within natural environments. To help understand the underlying neurological disorder, we used fMRI to test the impact of amblyopia on the functional organization of scene-selective cortical areas, including the posterior intraparietal gyrus scene-selective (PIGS) area, a recently discovered region that responds selectively to ego-motion within naturalistic environments (Kennedy et al., 2024). Nineteen amblyopic adults (10 female) and thirty age-matched controls (12 female) participated in this study. Amblyopic participants spanned a wide range of amblyopia severity, based on their interocular visual acuity difference and stereoacuity. The visual function questionnaire (VFQ-39) was used to assess the participants' perception of their visual capabilities. Compared to controls, we found weaker scene-selective activity within the PIGS area in amblyopic individuals. By contrast, the level of scene-selective activity across the occipital place area (OPA), parahippocampal place area (PPA), and retrosplenial cortex (RSC)) remained comparable between amblyopic and control participants. The subjects' scores on "general vision" (VFQ-39 subscale) correlated with the level of scene-selective activity in PIGS. These results provide novel and direct evidence for amblyopia-related changes in scene-processing networks, thus enabling future studies to potentially link these changes across the spectrum of documented disabilities in amblyopia.

Patching in Children With Unilateral Congenital Cataract and Child Functioning and Parenting Stress

Importance

Parents may be concerned about the adverse outcomes of occlusion therapy in children treated for unilateral congenital cataract (UCC).

Objective

To determine whether occlusion therapy in children treated for UCC with poor visual outcomes is negatively associated with poorer child and/or family functioning.

Design, Setting, and Participants

This cohort study was conducted in 2023 using data collected between 2006 and 2016 in the Infant Aphakia Treatment Study (IATS). IATS participants with a visual acuity (VA) of 20/200 or worse were included. Statistical analysis was performed from July 2022 to October 2023.

Exposure

Caregivers reported the mean daily minutes of patching during the 12 months prior to the VA assessment at 4.5 years of age. Patching was categorized as minimal (<15 minutes per day), moderate (15 to <120 minutes per day), or extensive (≥120 minutes per day).

Main Outcome Measures

At 4.25 and 10.5 years of age, caregivers reported stress associated with the parenting role using the Parenting Stress Index and the Ocular Treatment Index and child behavior problems using the Achenbach Child Behavior Checklist. Motor skills were assessed at age 54 months using the Movement Assessment Battery for Children-Second Edition. Children completed the Harter Self-Perception Profile for Children at age 10.5 years. One-way analysis of variance and χ2 tests were used to compare outcomes by amount of patching.

Results

Patching data were available for 47 of 53 children (88.7%) with a VA of 20/200 or worse. Among these 47 children with patching data included in the study, 20 (42.5%) were female, 27 (57.5%) were male, 12 (25.5%) were reported to have been patched fewer than 15 minutes per day, 11 (23.4%) were patched 16 to 119 minutes per day, and 24 (51.1%) were patched at least 120 minutes per day. Parenting stress, child behavior problems, motor functioning, and child self-perception were similar in all groups. For example, after adjusting for gender and insurance status, there was a nonsignificant difference between mean stress scores of 11.0 (95% CI, -4.5 to 26.5) points for parents who reported minimal patching vs parents who reported patching at least 120 minutes per day, and there was no significant difference in children's report of their global self-worth (0.0 [95% CI, -0.4 to 0.3] points).

Conclusions and Relevance

Occlusion therapy was not negatively associated with family or child functioning. Although the sample size was limited, these results do not support changes to the current practice guidelines.

Reduced Retinal Vascular Density and Skeleton Length in Amblyopia

Purpose

This study aimed to investigate the possible relationship between retinal vascular abnormalities and amblyopia by analyzing vascular structures of fundus images.

Methods

In this observational study, retinal fundus images were collected from 36 patients with unilateral amblyopia, 33 patients with bilateral amblyopia, and 36 healthy control volunteers. We developed a customized training algorithm based on U-Net to digitalize the vasculature in the fundus images to quantify vascular density (area and fractal dimension), skeleton length, and number of bifurcation points. For statistical comparisons, this study divided participants into two groups. The amblyopic eyes and the fellow eyes of patients with unilateral amblyopia formed the paired group, while bilateral amblyopic patients and healthy controls formed the independent group.

Results

In the paired group, the vascular area (P = 0.007), vascular fractal dimension (P = 0.007), and vascular skeleton length (P = 0.002) of the amblyopic eyes were significantly smaller than those of the fellow eyes. In the independent group, significant decreases in the vascular fractal dimension (P = 0.006) and skeleton length (P = 0.048) were observed in bilateral amblyopia compared to control. The vascular area was also significantly correlated with best-corrected visual acuity in amblyopic eyes.

Conclusions

This study demonstrated that retinal vascular density and skeleton length in amblyopic eyes were significantly smaller compared to control, indicating an association between the changes in retinal vascular features and the state of amblyopia.

Translational Relevance

Our algorithm presents amblyopic retinal vascular changes that are more biologically interpretable for both clinicians and researchers.

Comparing paediatric optometric vision care in Canada over a 14-year period

PURPOSE

In Canada, teaching in paediatric eye care has increased in the past decade both within the optometry curriculum and as continuing education to optometrists. Paediatric vision care guidelines have also been established by North American optometric associations. This study examined whether this exposure was associated with changes in paediatric eye care in Canada over a 14-year period.

METHODS

Canadian optometrists were invited to participate in an anonymous 35-item survey in 2007 and 2021. The surveys sought to investigate optometrist's recommendations for first eye examinations, the number of paediatric patients seen in a typical week and preparedness to provide eye examinations to children. Response frequencies were determined for each survey item.

RESULTS

Across Canada, 133/1000 (13.3%) and 261/~6419 (~4.1%) optometrists responded to the survey in 2007 and 2021, respectively. No significant difference was found in the number of years practicing, days per week in practice and total number of patients seen per week. The modal age optometrists recommended children be seen for their first eye examination changed from 3-4 years in 2007 (53%) to 6-12 months in 2021 (61%). In 2007, 87% of respondents provided eye examinations to children <2 years, increasing to 94% in 2021 (p = 0.02). Despite a reduction in the recommended age between the two survey years, the most frequent age children were seen for their first eye examination was 3-4 years (30% in both surveys) and the most common age seen in a typical week remained unchanged (4-6 years-56% 2007; 66% 2021).

CONCLUSION

Although optometrists' willingness to provide paediatric eye care increased over the past 14 years, the number of children seen in a typical week did not change. Barriers to determine why more children are not being seen at an earlier age need to be investigated.

Expression of early growth responsive gene-1 in the lateral geniculate body of kittens with amblyopia caused by monocular form deprivation

OBJECTIVE

The expression of early growth responsive gene-1 (Egr-1) in the lateral geniculate body in the normal kittens and those affected with amblyopia caused by monocular visual deprivation was compared to explore the potential significance of Egr-1 in the pathogenesis of amblyopia.

METHODS

A total of 30 healthy kittens were equally and randomly divided into the control (n = 15) and the deprivation group (n = 15). The kittens were raised in natural light and the right eyes of the deprived kittens were covered with a black opaque covering. Pattern visual evoked potential (PVEP) was measured before and 1, 3, and 5 weeks after covering. Five kittens from each group were randomly selected and euthanized with 2% sodium pentobarbital (100 mg/kg) during the 1st, 3rd and 5th week after covering. The expression of Egr-1 in the lateral geniculate body in the two groups was compared by performing immunohistochemistry and in situ hybridization.

RESULTS

After three weeks of covering, PVEP detection indicated that the P100 wave latency in the deprivation group was significantly higher than that in the control group (P < 0.05), whereas the amplitude decreased markedly (P < 0.05). The number of the positive cells (P < 0.05) and mean optical density (P < 0.05) of Egr-1 protein expression in the lateral geniculate body of the deprivation group were found to be substantially lower in comparison to the normal group, as well as the number (P < 0.05) and mean optical density of Egr-1 mRNA-positive cells (P < 0.05). However, with increase of age, positive expression of Egr-1 in the control group showed an upward trend (P < 0.05), but this trend was not noted in the deprivation group (P > 0.05).

CONCLUSIONS

Monocular form deprivation can lead to substantially decreased expressions of Egr-1 protein and mRNA in the lateral geniculate body, which in turn can affect the normal expression of neuronal functions in the lateral geniculate body, thereby promoting the occurrence and development of amblyopia.

Prevalence of residual amblyopia in adulthood and its association on educational outcome and quality of life in the Northern Finland Birth Cohort

PURPOSE

The purpose of the current study was to evaluate the prevalence of residual amblyopia in adults in a population screened and treated in childhood. We also wanted to evaluate the association of amblyopia on school success, level of education, and quality of life.

METHODS

This is a follow-up study of 2708 subjects of the Northern Finland Birth Cohort. At the age of 46, the subjects took part in ophthalmic examinations, including the measurement of best-corrected visual acuity (BCVA) and refraction. Residual amblyopia was defined as BCVA 20/30 or less (logMAR ≥0.2) in one or both eyes or a two-line interocular visual acuity difference and absence of any pathological ocular factors. The quality of life was assessed with a 15D questionnaire, and educational outcome, school success, and episodic memory with a CANTAB-PAL (paired associates learning) test were evaluated.

RESULTS

The prevalence of amblyopia in the current adult population aged 46 years was 1.3% (n = 36). At 14 years, the amblyopia subjects had had significant differences in mean spherical equivalent between the amblyopic and fellow eye and strabismus more often than controls. No significant differences were observed in the CANTAB-PAL test or in educational outcome. However, amblyopia subjects had significant difficulties in the 15D questionnaire in terms of vision (54% vs. 34%, p = 0.01).

CONCLUSION

Due to screening and treatment in childhood, the number of adults with residual amblyopia was low. Despite minor visual impairment and discomfort, they cope very well in life in terms of educational outcome and quality of life.

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.

Parents' Awareness, Knowledge, and Perception of Amblyopia in Children: A Study in Jazan Region, Saudi Arabia

Background Amblyopia is a vision disorder that results from a development problem in the brain rather than a neurological disease in the eye. The condition causes reduced visual acuity in one or both eyes due to the brain's inability to process inputs, rather than a structural abnormality. This study aims to assess parents' awareness, knowledge, and perception of amblyopia in their children in the Jazan region, Saudi Arabia. Methods This is a cross-sectional study that used an electronic questionnaire consisting of five main sections to assess the level of awareness of amblyopia among parents in the Jazan region. The Statistical Package for Social Sciences (SPSS v.25, IBM Corp., Armonk, NY, USA) was utilized to input the data. The degree to which participants' level of awareness was related to variables such as age, gender, and educational level was assessed through the chi-square test (χ2), and any values that scored p-values under 0.05 were deemed statistically significant. Results The analysis included 572 participants, 395 mothers (69.0%) and 177 fathers (31.0%). The age groups of the participants were divided into 36-45 years (38.0%), 26-35 years (36.0%), and above 46 years (17.0%). Out of the total, 36 participants (6.0%) had a history of amblyopia, and 73 (13.0%) had a child who suffered from amblyopia. The findings showed that only 18 participants (3.1%) had a good awareness of amblyopia, while 242 (42.3%) had a fair level of awareness. Most participants, 312 (54.5%), were classified as having a poor awareness level of amblyopia. Parents with postgraduate degrees, those with prior awareness, and parents whose children had eye diseases demonstrated higher levels of good awareness. However, gender, age, and residency did not have significant associations with awareness levels. Conclusion While parents must be involved in managing amblyopia, our research found that more than half of the parents surveyed had a limited understanding of various aspects of the disease, which can cause permanent damage to their child's vision. Therefore, we recommend implementing health education programs to increase awareness and knowledge about amblyopia in Jazan.

Utilization and barriers to eye care following school-wide pediatric vision screening

OBJECTIVE

In August 2018, Ontario introduced the Child Visual Health and Vision Screening Protocol outlining school-based senior kindergarten (aged 4-6 years) vision screening. We determine the prevalence of children at risk based on screening in an Ontario community and follow up to determine resource utilization after screening.

METHODS

Vision screening data (HOTV, Randot, Autorefractor) from 41 schools (1127 children) were collected for the 2018-2019 and 2019-2020 school years. Phone follow-up was conducted 1-1.5 years after screening to determine whether an optometry visit occurred, if glasses were prescribed, and potential barriers to accessing eye care. Independent t tests were used to compare time to follow-up between groups, and χ2 testing was used for associations between material and social deprivation.

RESULTS

Overall screening resulted in a 32.2% referral rate within our region. Of the referred children who responded, the rate of seeking out eye care was 69.9% (n = 64), and 65.2% of these visits were prompted specifically by vision screening, and 34.4% of referred children respondents were prescribed glasses. There was a significant relationship between receiving a referral and living in a more materially deprived (p = 0.001) and a more socially deprived area (p = 0.006). The most frequently reported barriers were related to insufficient insurance coverage for eye care or glasses, COVID-19-related difficulties, and scheduling conflicts.

CONCLUSION

Our vision screening program identified and referred more than one third of children screened for follow-up eye examinations, with children in more deprived neighbourhoods being more frequently referred. Around two thirds of referred children sought care, and one third were prescribed glasses in the follow-up sample.

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.

Cost-effectiveness of Universal School- and Community-Based Vision Testing Strategies to Detect Amblyopia in Children in Ontario, Canada

IMPORTANCE

Screening for amblyopia in primary care visits is recommended for young children, yet screening rates are poor. Although the prevalence of amblyopia is low (3%-5%) among young children, universal screening in schools and mandatory optometric examinations may improve vision care, but the cost-effectiveness of these vision testing strategies compared with the standard in primary care is unknown.

OBJECTIVE

To evaluate the relative cost-effectiveness of universal school screening and mandated optometric examinations compared with standard care vision screening in primary care visits in Toronto, Canada, with the aim of detecting and facilitating treatment of amblyopia and amblyopia risk factors from the Ontario government's perspective.

DESIGN, SETTING, AND PARTICIPANTS

An economic evaluation was conducted from July 2019 to May 2021 using a Markov model to compare 15-year costs and quality-adjusted life-years (QALYs) between school screening and optometric examination compared with primary care screening in Toronto, Canada. Parameters were derived from published literature, the Ontario Schedule of Benefits and Fees, and the Kindergarten Vision Testing Program. A hypothetical cohort of 25 000 children aged 3 to 5 years was simulated. It was assumed that children in the cohort had irreversible vision impairment if not diagnosed by an optometrist. In addition, incremental costs and outcomes of 0 were adjusted to favor the reference strategy. Vision testing programs were designed to detect amblyopia and amblyopia risk factors.

MAIN OUTCOMES AND MEASURES

For each strategy, the mean costs per child included the costs of screening, optometric examinations, and treatment. The mean health benefits (QALYs) gained were informed by the presence of vision impairment and the benefits of treatment. Incremental cost-effectiveness ratios were calculated for each alternative strategy relative to the standard primary care screening strategy as the additional cost required to achieve an additional QALY at a willingness-to-pay threshold of $50 000 Canadian dollars (CAD) ($37 690) per QALY gained.

RESULTS

School screening relative to primary care screening yielded cost savings of CAD $84.09 (95% CI, CAD $82.22-$85.95) (US $63.38 [95% CI, US $61.97-$64.78]) per child and an incremental gain of 0.0004 (95% CI, -0.0047 to 0.0055) QALYs per child. Optometric examinations relative to primary care screening yielded cost savings of CAD $74.47 (95% CI, CAD $72.90-$76.03) (US $56.13 [95% CI, $54.95-$57.30]) per child and an incremental gain of 0.0508 (95% CI, 0.0455-0.0561) QALYs per child. At a willingness-to-pay threshold of CAD $50 000 (US $37 690) per QALY gained, school screening and optometric examinations were cost-effective relative to primary care screening in only 20% and 29% of iterations, respectively.

CONCLUSIONS AND RELEVANCE

In this study, because amblyopia prevalence is low among young children and most children in the hypothetical cohort had healthy vision, universal school screening and optometric examinations were not cost-effective relative to primary care screening for detecting amblyopia in young children in Toronto, Canada. The mean added health benefits of school screening and optometric examinations compared with primary care screening did not warrant the resources used.

Evaluating validity and reliability of the Arabic-version low-vision quality-of-life questionnaire

Low-vision quality-of-life questionnaire (LVQOL) has not been developed in the Arabic language, and none has been translated into Arabic. This study would demonstrate the effectiveness of the translated questionnaire. The English LVQOL was translated into Arabic (ARB-LVQOL) through five stages. A total of 52 low vision and 30 normally sighted individuals participated in this study. The internal consistency reliability, item-total correlation reliability, construct validity, convergent validity, discriminative validity, and respondent burden of the ARB-LVQOL were calculated. The translation team recommended that the ARB-LVQOL replicated the meaning of the LVQOL. The cultural differences were also noted during the translation process. Cronbach’s coefficient was α = 0.90 in both low vision (LV) and simulated groups. The item-total correlation ranged from 0.50 to 0.70 in both groups. The intra-class correlation coefficient indicated good test–retest reliability (LV group, ranged 0.82–0.93; control group ranged 0.83–0.94). The factor analysis, using varimax rotation, of the ARB-VQOL identified seven factors. A moderate to a strong relationship between the score of each domain with the total index score was observed, indicating an adequate convergent validity. The ARB-LVQOL discriminated between normally sighted and simulated low-vision participants and also to some extent between the simulated and real low-vision individuals. The respondent burden was less than 15 min in most responses. The ARB-LVQOL was found to relate well with patients’ visual functions and some patients’ characteristics, providing further evidence of the validity of ARB-LVQOL. The ARB-LVQOL showed psychometric properties analogous to the English version. The ARB-LVQOL could be used in clinical settings and research in adults with low vision in Arabic populations.

A Social Media Listening Study to Understand the Unmet Needs and Quality of Life in Adult and Pediatric Amblyopia Patients

INTRODUCTION

Amblyopia is an important cause of monocular vision impairment worldwide, and it negatively impacts patients' quality of life (QoL). Understanding patients' perspectives may help to optimize treatment outcomes and improve treatment adherence.

METHODS

This was a non-interventional, retrospective analysis of social media data available in the public domain posted by patients and caregivers on selected social media channels (Twitter®, forums, blogs, and news) from 12 countries between July 2018 and June 2020.

RESULTS

Approximately 2662 conversations relevant to the research objective were analyzed. The patient journey for adults and children was constructed based on the conversations. Eyeglasses, eye patches, contact lenses, and vision exercises were the common treatment options for amblyopia. Patients also reported vision improvement with emerging technologies such as digital therapeutics. Amblyopia and its treatment had a negative impact on QoL, and increased caregiver burden. Insurance coverage, long appointment waiting times, and recurring expenses of treatment options were reported as barriers to treatment. Non-compliance, switching between treatment options or technology, or discontinuation of treatment options was found to emanate from various issues including no improvement of the condition, discomfort with the treatment option, bullying, dissatisfaction with healthcare professional (HCP) recommendation, cost of treatment/issues with insurance coverage, side effects, and/or other unspecified reasons. The need for regular eye examinations, better diagnostic tests, awareness of the disease, awareness amongst HCPs about treatment options, and the need for better health insurance coverage policies emerged as unmet needs.

CONCLUSION

This social media listening study generated insights on patients with amblyopia and their caregivers regarding the patient journey, treatment options, reasons for non-compliance, reasons for switching HCPs, barriers to treatment, and unmet needs. Further qualitative research is required to validate the findings.

Adverse Influences of Nonstrabismic Amblyopia on Quality of Life of Teenagers in China

The aim of this study was to explore the influences of nonstrabismic amblyopia on quality of life in adolescents. Health-related quality of life (HRQoL) scale, a multidimensional construct that indicates a fundamental health outcome, was used to measure physical and psychosocial functioning of the adolescents. Forty teenagers with nonstrabismic amblyopia and 40 control teenagers without nonstrabismic amblyopia were recruited between April 2019 and July 2021. The anthropometric measures, body image, physical activity outcome, and HRQoL scores including physical health, emotional functioning, social functioning, and school functioning were compared between the two groups. The results revealed that teenagers with nonstrabismic amblyopia had less weekly sedentary time (P < 0.001), weekly total steps (P < 0.001), and worse school functioning (P = 0.0211) than control teenagers. No significant difference was found in anthropometric measures and body image between the two groups (P > 0.05). This study implied the needs for teenagers with nonstrabismic amblyopia to enhance physical activities. Teachers and parents are encouraged to pay more attention to teenagers with nonstrabismic amblyopia to improve their school functioning.

Treatment compliance in amblyopia: A mini-review and description of a novel online platform for compliance tracking

Patient compliance with amblyopia therapies, including eye patching and atropine drops, is crucial for optimal visual acuity outcomes. Studies utilizing objective measures of compliance measurement have consistently shown that a majority of patients receive significantly less treatment than prescribed. We review the subjective and objective compliance rates reported in the literature, assess possible explanations for poor compliance and describe studies of interventions to improve compliance. Additionally, we report our experience implementing Inside Out Care, a novel online platform designed to improve monitoring of amblyopia patient compliance, in our clinics. We have found that this platform, which is accessible via both computer and smartphone, has improved monitoring of amblyopia patient patching compliance, as well as allowed for enhanced doctor-patient communication.

Reasons why we might want to question the use of patching to treat amblyopia as well as the reliance on visual acuity as the primary outcome measure

Recent evidence suggests that the primary deficit in amblyopia is loss of binocular vision and that the loss of monocular acuity is a secondary consequence. This new understanding derived from recent laboratory studies questions the present therapy and its primary acuity-based endpoint, which have been the gold standard in the treatment of this condition for the past 200 years.

Accommodative Lag Persistence in Treated Anisometropic, Strabismic, and Mixed Amblyopia

Background

Amblyopic eyes typically exhibit greater lag of accommodation. Whether this improves after amblyopia treatment is inconclusive. The aim of this study is to report post-treatment accommodative response in amblyopia and to investigate if the lag is associated with visual acuity, treatment duration, and amblyopia type.

Methods

Monocular and binocular accommodative responses were measured using Nott's method of dynamic retinoscopy in amblyopia of anisometropic, strabismic, and combined anisometropic-strabismic types and age-matched controls with normal vision. The results were compared using the nonparametric Wilcoxon signed ranks test. Linear regression analysis was used to examine association of the lag to refractive error, duration of therapy, and visual acuity.

Results

Mean ± SD age of 46 amblyopic and 20 control subjects were 6.9 ± 1.8 and 6.9 ± 2.2 years, respectively. At the time of the study, 30 amblyopic subjects were receiving patching therapy and ceased in the remainder. In amblyopic eyes, mean ± SD monocular and binocular lags were 1.2 ± 0.6D and 1.0 ± 0.5D (p < 0.001), respectively, compared to 0.6 ± 0.3D and 0.5 ± 0.2D (p < 0.005), respectively, in nonamblyopic eyes and 0.4 ± 0.2D and 0.3 ± 0.2D (p=0.093), respectively, in the controls. By types, the monocular lag was significantly higher than the binocular lag (p=0.001) in mixed amblyopia (p=0.004); they were similar in anisometropic (p=0.283) and strabismic (p=0.743) amblyopia. Monocular lag was significantly correlated to BCVA (r = 0.46; p=0.001) and refraction (r = 0.42; p=0.001) but not to patching duration (r = 0.1; p=0.280).

Conclusion

Inadequate accommodative response, a higher lag, persists in amblyopic eyes even after the treatment. Impaired accommodative response is partly determined by posttherapy visual acuity. Further studies investigating the effect of accommodative lag on visual recovery and whether optical correction of the deficiency may improve visual outcome of the treatment are recommended.

Can pattern electroretinography be a relevant diagnostic aid in amblyopia? - A systematic review

INTRODUCTION

Pattern Electroretinography (PERG) is a highly sensitive electrophysiological technique used as an indicator of changes in retinal macular area. Amblyopia seems to result from a cortical visual imbalance but changes at the retinal level may also be present. The purpose of this systematic review was to evaluate if there are any consistent changes described in the scientific literature in PERG responses of amblyopic eyes.

MATERIALS AND METHODS

Searches were conducted in PubMed and Embase databases, using the keywords "Electroretinography" and "Amblyopia", combined with MeSH or Emtree terms "Pattern Electroretinography", "amblyopia", "PERG" and "amblyopia". PERG P50-N95 amplitude and P50 latency were analysed as well as the methodology used.

RESULTS

A total of 234 articles were found and 6 articles were included for review. One of the articles reported results in adults and five of them in children. One of the articles in children reported no changes in either P50-N95 amplitude or P50 latency. All articles that described differences between the amblyopic eye and the normal eye found a decrease in P50-N95 amplitude and/or a delay in P50 latency.

CONCLUSIONS

This review shows promising findings for the use of PERG in amblyopia as an aid in the diagnostic protocol, since this technique may be able to detect an apparent functional impairment of the amblyopic eye.

Quality of life during occlusion therapy for amblyopia from the perspective of the children and from that of their parents, as proxy

BACKGROUND

Parents pity their amblyopic child when they think that they suffer from occlusion therapy. We measured health-related quality of life during occlusion therapy.

METHODS

We developed the Amblyopia Parents and Children Occlusion Questionnaire (APCOQ). It was designed by a focus group of patients, orthoptists and ophthalmologists and consisted of twelve items concerning skin contact of patch, activities, contact with other children, emotions and awareness of necessity to patch. Parents filled out the Proxy Version shortly before the Child Version was obtained from their child. Child Version item scores were compared with Proxy Version item scores and related to the child's age, visual acuity, refraction, angle of strabismus, and cause of amblyopia.

RESULTS

63 children were recruited by orthoptists, and their parents agreed to participate. Three children were excluded: one child with Down-syndrome, one child with cerebral palsy, and one child who had been treated by occlusion therapy. Included were 60 children (mean age 4.57 ± 1.34 SD) and 56 parents. Children had occluded 128 ± 45 SD days at interview. Prior to occlusion, 54 children had worn glasses. Cronbach's α was 0.74 for the Child Version and 0.76 for the Proxy Version. Children judged their quality of life better than their parents did, especially pertaining to skin contact and activities like games and watching TV. Notably, 13 children with initial visual acuity ≥ 0.6 logMAR in the amblyopic eye experienced little trouble with games during occlusion. Quality of life in eight children with strabismus of five years and older correlated negatively (Spearman rank mean rho = -0.43) with angle of strabismus. Children with amblyopia due to both refractive error and strabismus (n = 14) had, relatively, lowest quality of life, also according to their parents, as proxy. Several children did not know why they wore a patch, contrary to what their parents thought.

CONCLUSIONS

Children's quality of life during occlusion therapy is affected less than their parents think, especially regarding skin contact, playing games and watching TV during occlusion. Quality of life correlates negatively with the angle of strabismus in children five years and older. Children do not know why they wear a patch, contrary to what their parents think. Notably, children with low visual acuity in the amblyopic eye, had little difficulty playing games.

A Randomized Trial of Binocular Dig Rush Game Treatment for Amblyopia in Children Aged 4 to 6 Years

SIGNIFICANCE

Binocular treatment for unilateral amblyopia is an emerging treatment that requires evaluation through a randomized clinical trial.

PURPOSE

This study aimed to compare change in amblyopic-eye visual acuity (VA) in children aged 4 to 6 years treated with the dichoptic binocular iPad (Apple, Cupertino, CA) game, Dig Rush (not yet commercially available; Ubisoft, Montreal, Canada), plus continued spectacle correction versus continued spectacle correction alone.

METHODS

Children (mean age, 5.7 years) were randomly assigned to home treatment for 8 weeks with the iPad game (prescribed 1 h/d, 5 d/wk [n = 92], or continued spectacle correction alone [n = 90]) in a multicenter randomized clinical trial. Before enrollment, children wearing spectacles were required to have at least 16 weeks of wear or no improvement in amblyopic-eye VA (<0.1 logMAR) for at least 8 weeks. Outcome was change in amblyopic-eye VA from baseline to 4 weeks (primary) and 8 weeks (secondary) assessed by masked examiner.

RESULTS

A total of 182 children with anisometropic (63%), strabismic (16%; <5∆ near, simultaneous prism and cover test), or combined-mechanism (20%) amblyopia (20/40 to 20/200; mean, 20/63) were enrolled. After 4 weeks, mean amblyopic VA improved by 1.1 logMAR lines with binocular treatment and 0.6 logMAR lines with spectacles alone (adjusted difference, 0.5 lines; 95.1% confidence interval [CI], 0.1 to 0.9). After 8 weeks, results (binocular treatment: mean amblyopic-eye VA improvement, 1.3 vs. 1.0 logMAR lines with spectacles alone; adjusted difference, 0.3 lines; 98.4% CI, -0.2 to 0.8 lines) were inconclusive because the CI included both zero and the pre-defined difference in mean VA change of 0.75 logMAR lines.

CONCLUSIONS

In 4- to 6-year-old children with amblyopia, binocular Dig Rush treatment resulted in greater improvement in amblyopic-eye VA for 4 weeks but not 8 weeks. Future work is required to determine if modifications to the contrast increment algorithm or other aspects of the game or its implementation could enhance the treatment effect.

Practice patterns in the management of amblyopia among optometrists in Ghana

Despite internationally recognized guidelines, amblyopia management varies among eye care professionals worldwide. Hence, we sought to investigate the practice patterns of amblyopia management and the factors associated with the decision to treat amblyopia among optometrists in Ghana. A cross-sectional survey was conducted among registered optometrists in Ghana from January 2020 to October 2020. Data collection was done through the administration of online questionnaires via e-mail (google form). The structured questionnaires included demographic information, mode, and scope of practice, diagnostic criteria, examination procedures, treatment modalities, and prognosis. A p value of less than 0.05 was deemed statistically significant. The mean (±SD) age of all the 168 respondents was 32.6 (±6.1) years (range: 24-50 years). The majority of the optometrists (64.9%) treated amblyopia in their practice; with the most prevalent being refractive amblyopia (68.2%), followed by strabismic amblyopia (27.1%), then form-deprivation amblyopia (4.7%). Most (76.1%) amblyopic patients presented with symptomatic squinting. The most common ocular and medical history was anisometropia (90.0%), and the most common diagnostic procedures were patient history, visual acuity, and refraction. Optical correction (88.3%) was mainly prescribed for amblyopia treatment, followed by patching (58.5%). Nearly half of the respondent (45.0%) reported good prognosis after amblyopia treatment. After statistical adjustment, female optometrists were significantly associated with decreased odds of treating amblyopia (AOR = 0.36, p = .004). Refractive amblyopia is the main type of amblyopia managed by optometrists in Ghana. Hence, optical correction is the primary treatment regime. Current amblyopia management practice among optometrists adhere to recommended guidelines and our findings demonstrate uniformity in the standard of care.

Effect of Sequential and Simultaneous Patching Regimens in Unilateral Amblyopia

PURPOSE

Many clinicians treat unilateral amblyopia with glasses alone and initiate patching when needed; others start glasses and patching simultaneously. In this study, we reviewed the outcomes of the two approaches at our institution.

DESIGN

Retrospective nonrandomized clinical trial.

METHODS

Setting: Institutional practice.

PATIENT POPULATION

All patients diagnosed with amblyopia at Boston Children's Hospital between 2010 and 2014.

INCLUSION CRITERIA

Unilateral amblyopia (visual acuity (VA) 20/40 to 20/200 with interocular difference ≥3 lines,) age 3 to 12 years, with a 6-month follow-up visit.

EXCLUSION CRITERIA

Deprivation amblyopia, prior amblyopia treatment, treatment other than patching, surgery. Patients were categorized as "simultaneous treatment" (concurrent glasses and patching therapy at their first visit) or "sequential treatment" (glasses alone at first visit, followed by patching therapy at second visit.) Observation procedures: Patient demographics, VA, and stereopsis were compared.

OUTCOME MEASURES

VA and stereopsis at the last visit on treatment.

RESULTS

We identified 98 patients who met inclusion criteria: 36 received simultaneous treatment and 62 sequential treatment. Median amblyopic eye VA improved similarly between the simultaneous (∆0.40; interquartile range [IQR], 0.56-0.30 logMAR) and sequential (∆0.40; IQR, 0.52-0.27 logMAR) groups. Patients without stereopsis at first visit had better stereopsis outcomes with sequential treatment (5.12 [IQR, 4.00-7.51] log stereopsis) compared with simultaneous treatment (8.01 [IQR, 5.65-9.21]) log stereopsis, P = 0.046).

CONCLUSIONS

VA improved approximately 4 lines regardless of treatment type. For children without stereopsis at first presentation, sequential patching yielded better stereopsis outcomes. These findings require further validation and highlight the importance of evaluating stereopsis in future studies.

Management of amblyopia in pediatric patients: Current insights

Amblyopia is a cause of significant ocular morbidity in pediatric population and may lead to visual impairment in future life. It is caused due to formed visual deprivation or abnormal binocular interactions. Several risk factors in pediatric age group may lead to this disease. Author groups have tried managing different types of amblyopia, like anisometropic amblyopia, strabismic amblyopia and combined mechanism amblyopia, with optical correction, occlusion therapy, penalization, binocular therapy and surgery. We review historical and current management strategies of different types of amblyopia affecting children and outcomes in terms of visual acuity, binocularity and ocular deviation, highlighting evidence from recent studies. Literature searches were performed through Pubmed. Risk factors for amblyopia need to be identified in pediatric population as early in life as possible and managed accordingly, as visual outcomes in amblyopia are best if treated at the earliest. Although, monocular therapies like occlusion or penalization have been shown to be quite beneficial over the years, newer concepts related to binocular vision therapy are still evolving.

Impact of Persisting Amblyopia on Socioeconomic, Health, and Well-Being Outcomes in Adult Life: Findings From the UK Biobank

OBJECTIVES

This study aimed to investigate associations between persisting amblyopia into adulthood and its "real-life" impacts and inform the current debate about the value of childhood vision screening programs.

METHODS

Associations between persisting amblyopia and diverse socioeconomic, health, and well-being outcomes were investigated in multivariable-adjusted (sex, age, ethnicity, deprivation) regression models, with 126 400 participants (aged 40-70 years) of the UK Biobank with complete ophthalmic data. Analysis by age group (cohort 1, 60-70 years; cohort 2, 50-59 years; cohort 3, 40-49 years) assessed temporal trends.

RESULTS

Of 3395 (3%) participants with confirmed amblyopia, overall 77% (2627) had persisting amblyopia, declining from 78% in cohort 1 to 73% in cohort 3. The odds of persisting amblyopia were 5.91 (5.24-6.66) and 2.49 (2.21-2.81) times greater in cohort 1 and cohort 2, respectively, than cohort 3. The odds were also higher for more socioeconomically deprived groups and for white ethnicity. Reduced participation in sport, adverse general and mental health, and well-being were all independently associated with persisting amblyopia, with the strongest associations in the youngest cohorts. Associations with lower educational attainment and economic outcomes were only evident in the oldest cohort.

CONCLUSIONS

There has been a decline in the overall frequency of persisting amblyopia since the introduction of universal child vision screening in the United Kingdom. Nevertheless, most adults treated for amblyopia in childhood have persisting vision deficits. There was no evidence that persisting amblyopia has vision-mediated effects on educational, employment-related, or economic outcomes. The observed adverse outcomes were largely those not directly mediated by vision. Patients undergoing treatment should be counseled about long-term outcomes.

Amblyopia and Routine Eye Exam in Children: Parent's Perspective

Amblyopia is a reduced best-corrected visual acuity of one or both eyes that cannot be attributed to a structural abnormality; it is a functional reduction in the vision of an eye caused by disuse during a critical period of visual development. It is considered the leading cause of visual defects in children. With early diagnosis and treatment, children with amblyopia can significantly improve their vision. However, if it is neglected and not treated during childhood, unfortunately, it permanently decreases vision. Therefore, prevention, detection, and treatment largely depend on parents. This article explores parents' perspectives on amblyopia and routine examination of their children's eyes. A cross-sectional study used an electronic questionnaire consisting of five main sections to assess the level of awareness of amblyopia among parents. As a result, a total of 325 participants were included in our analysis. 209 (64.3%) were mothers, and 116 (35/7%) were fathers. The age groups were 35-50 years of age (61.5%), 20-34 years (23.4%), and older than 50 years (15%). Participants with a history of amblyopia numbered 23 (7.1%), and 39 had an amblyopic child (12%). A good awareness level of amblyopia among parents was found in only 10 (3%) participants, a fair awareness level in 202 (62%), and 113 (35%) participants were classified as having a poor awareness level of amblyopia. Only 13.8% of the parents took their children for yearly routine eye exams, while the majority (72%) took their children only if they had a complaint, and 14.2% took them for eye checkups only before school entry. In conclusion, parents' awareness of amblyopia in Tabuk City, KSA, was low. In addition, a limited proportion of parents reported consistently taking their children for routine eye exams. Therefore, raising awareness should be considered in public education regarding the disease.

Egocentric Distance Perception Disorder in Amblyopia

Egocentric distance perception is a psychological process in which observers use various depth cues to estimate the distance between a target and themselves. The impairment of basic visual function and treatment of amblyopia have been well documented. However, the disorder of egocentric distance perception of amblyopes is poorly understood. In this review, we describe the cognitive mechanism of egocentric distance perception, and then, we focus on empirical evidence for disorders in egocentric distance perception for amblyopes in the whole visual space. In the personal space (within 2 m), it is difficult for amblyopes to show normal hand-eye coordination; in the action space (within 2 m~30 m), amblyopes cannot accurately judge the distance of a target suspended in the air. Few studies have focused on the performance of amblyopes in the vista space (more than 30 m). Finally, five critical topics for future research are discussed: 1) it is necessary to systematically explore the mechanism of egocentric distance perception in all three spaces; 2) the laws of egocentric distance perception in moving objects for amblyopes should be explored; and 3) the comparison of three subtypes of amblyopia is still insufficient; 4) study the perception of distance under another theoretical framework; 5) explore the mechanisms of amblyopia by Virtual Reality.

A mhealth application for automated detection and diagnosis of strabismus

BACKGROUND AND OBJECTIVE

Amblyopia is a public health problem, and strabismus is its primary cause. Our objective is to evaluate the concordance of the diagnosis of strabismus between strabismus expert ophthalmologist and the mhealth application developed for this purpose.

METHODS

We evaluated the concordance of the diagnosis of strabismus between the expert ophthalmologist and the mhealth application by screening 224 children and adolescents in the 5-15 years age group, with snapshots of patients' eyes and their analysis thereof. We were using a multifunctional cell phone with Android and the ophthalmologist's clinical evaluation by analyzing the ocular deviations using simple cover and prism and alternate cover.

RESULTS

Fraction measurements were used with two cutoff points of 6 and 11 prismatic diopters (PD). Results were compared according to their concordances, with a fair Kappa equal to 0.43 (95%CI = [0.38; 0.48]), which was statistically significant (p < 0.0001) at the cutoff point of 6 PD and Kappa equal to 0.49 (95% CI = [0.35; 0.61]), which was statistically significant (p < 0.042) in the cutoff point of 11 PD.

CONCLUSIONS

The cutoff point of 6 PD was chosen for screening by this mhealth application since it caused the loss of only two patients with strabismus, whereas, in the case of 11 PD, the loss was five patients in the universe of 224. These results are promising for the use of this software as a screening method for patients with strabismus.

The impact of monocular and binocular visual impairment on the quality of life of Brazilian children

The purpose of this case–control study was to assess the quality of life (QoL) in children with visual impairment from an urban area in Brazil. Participants included children with binocular and monocular visual impairment and normal controls aged between 4 and 15 years. All subjects underwent a basic ophthalmic exam and answered the Pediatric Quality of Life Inventory™ (PedsQL). The score results were compared among the groups with analysis of variance (ANOVA). The sample included 45 children with visual disability (24 binocular and 21 monocular) and 30 age-matched controls. The groups did not differ in age and gender distribution. The child self-report score for the binocular visual impairment group was lower when compared to controls in all four core scales; as compared to monocular children, the binocular group scored lower in physical health and social functioning. The total score of binocular children (67.9 ± 25.2) was lower than that for monocular children (83.0 ± 13.3, p = .01) and controls (84.2 ± 13.6, p < .001). Children with monocular visual disability presented very similar scores to controls in both self-reported and parent proxy inventory (81.6 ± 15.2, p = .97 and 81.9 ± 15.3, p = .99, respectively). These data should help governments develop public health interventions and rehabilitation strategies for visually disabled children.

Knowledge and attitudes regarding amblyopia among parents in Jeddah, Saudi Arabia: a cross-sectional study

Objectives

To assess parents’ perceptions about amblyopia and its causes, symptoms, risk factors, treatments, and the importance of follow-up and to evaluate their awareness regarding the consequences and critical complications.

Results

Parents or their companions (n = 401) were surveyed, and 52.9% were mothers, 81.8% of mothers and 85.7% of fathers were highly educated (diploma, college or university degree), and 58 (14.5%) had a child who was afflicted with amblyopia. The knowledge subscale (nine items) showed acceptable reliability. Twenty percent of the participants declared having adequate knowledge about amblyopia, but assessment by item showed low percentages of an adequate knowledge level, ranging from 0% for amblyopia causes, 35.9% for definition, and 59.9% for whether amblyopia is a hereditary disease. Thus, the rate of adequate knowledge (Knowledge Score ≥ 8) was 25.9%, and was associated with parents’ nationality (p < 0.05) and self-declared knowledge about amblyopia (p < 0.001). No significant difference was observed among respondents who had a child with amblyopia. There was a lack of knowledge about basic information and different aspects of the disease, which emphasized the relevance of school-based screening programs and adequate use of trustworthy internet resources using easily understood medical information.

Applications of augmented reality in ophthalmology [Invited]

Throughout the last decade, augmented reality (AR) head-mounted displays (HMDs) have gradually become a substantial part of modern life, with increasing applications ranging from gaming and driver assistance to medical training. Owing to the tremendous progress in miniaturized displays, cameras, and sensors, HMDs are now used for the diagnosis, treatment, and follow-up of several eye diseases. In this review, we discuss the current state-of-the-art as well as potential uses of AR in ophthalmology. This review includes the following topics: (i) underlying optical technologies, displays and trackers, holography, and adaptive optics; (ii) accommodation, 3D vision, and related problems such as presbyopia, amblyopia, strabismus, and refractive errors; (iii) AR technologies in lens and corneal disorders, in particular cataract and keratoconus; (iv) AR technologies in retinal disorders including age-related macular degeneration (AMD), glaucoma, color blindness, and vision simulators developed for other types of low-vision patients.

Prevalence of Amblyopia and Associated Risk Factors in Tibetan Grade One Children

INTRODUCTION

Amblyopia is an important public health problem and standard screening is quite necessary for early diagnosis and treatment especially for the remote areas. As the place of the largest Tibetan population, the Tibetan Plateau has special geographical characteristics such as high altitude, time zone, and ethnic composition, where very little information is available about the prevalence of amblyopia and other ocular diseases. The article aims to determine the prevalence of amblyopia and associated factors in grade 1 Tibetan children, living in Lhasa, Tibet Autonomous Region.

METHODS

A cross-sectional study was conducted. All the participants were scheduled for comprehensive eye examinations including visual acuity testing, ocular deviation and movement evaluation, cycloplegic refraction and examinations of the external eye, anterior segment, media, and fundus. Amblyopia was assessed in the children according to the standard definition.

RESULTS

A total of 1,856 students participated in the examinations (97.58% response rate). 1,852 students completed all the related examinations, and 34 of them were diagnosed as amblyopia with the prevalence of 1.84% (95% confidence interval [CI]: 1.22-2.45%). Unilateral amblyopia was diagnosed in 23 students (1.24%, 95% CI: 0.74-1.75%), including 16 anisometropic, 4 strabismic, 1 visual deprivational, and 2 mixed. Other 11 students were diagnosed as bilateral amblyopia (0.59%, 95% CI: 0.24-0.94%), including 9 ametropic, 1 deprivational, and 1 with nystagmus. The mean cylinder refraction and absolute value of the spherical equivalent refraction of amblyopic eyes was respectively -2.15 ± 1.52 D and 2.70 ± 2.33 D. Amblyopia was significantly associated with hyperopia (≥+2.00 D, odds ratio [OR] 8.22, 95% CI 3.42-19.72), astigmatism (≤-2.00 D, OR 6.76, 95% CI 2.56-17.85), and anisometropia (≥+0.50 to <+1.00 D, OR 3.95, 95% CI 1.44-10.79; ≥+1.00 D, OR 21.90, 95% CI 8.24-58.18).

CONCLUSIONS

The prevalence of amblyopia in grade 1 students of Lhasa is relatively higher than that of many other ethnic populations in China previously reported. Refractive errors including anisometropia, hyperopia, and astigmatism are the major risk factors of amblyopia.

An update on pharmacological treatment options for amblyopia

Amblyopia is a common cause of visual impairment in children and young adults. The cornerstone in the management of this disorder is based on increasing visual stimulation of the amblyopic eye by occlusion, by administering atropine or by causing optical penalization of the dominant eye. All these treatment options have shown some limits in terms of efficacy, due to the suboptimal treatment adherence for the patients and the lack of long-term clinical outcomes. Moreover, although it is well known that clinical efficacy decreases with age, new evidence is suggesting that cortical plasticity can be induced also in older children. For these reasons, new treatment options are being studied, in order to extend the "treatment window" beyond the critical period also in older patients. In this review, we will discuss all the most promising novel pharmacological agents in the management of amblyopia.

Efficacy of interventions for amblyopia: a systematic review and network meta-analysis

BACKGROUND

Many treatments are currently available for amblyopic patients; although, the comparative efficacy of these therapies is unclear. We conducted a systematic review and network meta-analysis (NMA) to establish the relative efficacy of these treatments for amblyopia.

METHODS

Electronic databases (MEDLINE, EMBASE, Cochrane Library) were systematically searched from inception to Sep. 2019. Only Randomized clinical trials comparing any two or three of the following treatments were included: refractive correction (spectacles alone), patching of 2 h per day (patch 2H), patch 6H, patch 12H, patch 2H + near activities (N), patch 2H + distant activities (D), atropine (Atr) daily, Atr weekly, Atr weekly + plano lens over the sound eye (Plano), optical penalization and binocular therapy. The reviewers independently extracted the data according to the PRISMA guidelines; assessed study quality by Cochrane risk-of-bias tool for randomized trials. The primary outcome measure was the change in best-corrected visual acuity (BCVA) expressed as log MAR lines. Direct comparisons and a Bayesian meta-analysis were performed to synthesize data.

RESULTS

Twenty-three studies with 3279 patients were included. In the network meta-analysis, optical penalization was the least effective of all the treatments for the change of visual acuity, spectacles (mean difference [MD], 2.9 Log MAR lines; 95% credibility interval [CrI], 1.8-4.0), patch 2H (MD, 3.3; 95% CrI, 2.3-4.3), patch 6H (MD, 3.6; 95% CrI, 2.6-4.6), patch 12H (MD, 3.4; 95% CrI, 2.3-4.5), patch 2H + N (MD, 3.7; 95% CrI, 2.5-5.0), patch 2H + D (MD, 3.5; 95% CrI, 2.1-5.0), Atr daily (MD, 3.2; 95% CrI, 2.2-4.3), Atr weekly (MD, 3.2; 95% CrI, 2.2-4.3), Atr weekly + Plano (MD, 3.7; 95% CrI, 2.7-4.7), binocular therapy (MD, 3.1; 95% CrI, 2.0-4.2). The patch 6H and patch 2H + N were better than spectacles ([MD, 0.73; 95% Crl, 0.10-1.40]; [MD, 0.84; 95% CrI, 0.19-1.50]).

CONCLUSIONS

The NMA indicated that the efficacy of the most of the examined treatment modalities for amblyopia were comparable, with no significant difference. Further high quality randomized controlled trials are required to determine their efficacy and acceptability.

SYSTEMATIC REVIEW REGISTRATION

CRD42019119843.

Quality of life and mental health in amblyopic children treated with and without occlusion therapy

PURPOSE

To assess the long-term (≥1 year) psychosocial effects of occlusion therapy in children with refractive amblyopia and their caregivers.

METHODS

Multiple self-reported questionnaires were used to investigate HRQoL, anxiety, depression, and stress in a cross-sectional study of children with refractive amblyopia and their caregivers. Children were divided into two subgroups: those treated with glasses only and those treated with both glasses and occlusion therapy who had stopped wearing a patch at least 1 year earlier.

RESULTS

A total of 79 children were included: 32 in the refraction-only group and 47 in the glasses + occlusion group. Median age of subjects was 12 years (IQR = 3.0). Mean age of the 79 caregivers was 41.9 ± 5.0 years. No significant differences were found for any of the psychosocial outcomes analyzed between children treated with glasses and patching and those treated with glasses only. The differences remained insignificant between children according to age of first occlusion (<6 vs ≥6 years). The only significant (but not clinically relevant) difference observed for caregivers was a higher score in the depression dimension of the Hospital Anxiety and Depression Scale for caregivers of children treated with glasses only (P = 0.036; effect size = 0.23).

CONCLUSIONS

In our study cohort, patching was not associated with long-term negative psychosocial outcomes in children with refractive amblyopia treated with occlusion therapy.

Global prevalence of amblyopia and disease burden projections through 2040: a systematic review and meta-analysis

Purpose

Amblyopia is a leading cause of vision impairment among children and young adults. Individual studies showed significant variations in the prevalence of amblyopia in different regions and age groups. This study is to estimate the global prevalence of amblyopia by pooling its prevalence from the previous studies and to project the number of people affected through 2040.

Methods

We performed a systematic review and meta-analysis on the prevalence of amblyopia using data published before 20 October 2018. We estimated the prevalence rate of amblyopia and its 95% CI globally and by subgroups (eg, region and age). The prevalence data were applied to United Nations World Population Prospects to derive the projected number with amblyopia through 2040.

Results

A meta-analysis of 60 studies (1 859 327 subjects) showed that the pooled prevalence rate of amblyopia was 1.44% (95% CI 1.17% to 1.78%). Prevalences in Europe (2.90%) and North America (2.41%) were higher than in Asia (1.09%) and Africa (0.72%). The highest prevalence was found in subjects over 20 years old (3.29%). There was no difference in the prevalence between genders. We estimated 99.2 (95% CI 71.7 to 146.1) million people with amblyopia in 2019 worldwide, increasing to 175.2 (95% CI 81.3 to 307.8) million by 2030 and 221.9 (95% CI 83.7 to 429.2) million by 2040.

Conclusions

The amblyopia is becoming a significant vision problem worldwide. It is of great importance to design and implement amblyopia screening, treatment and related public health strategies.

Comparison of amblyopia in schoolchildren in Ireland and Northern Ireland: a population-based observational cross-sectional analysis of a treatable childhood visual deficit

OBJECTIVES

This study reports the prevalence of persistent amblyopia (post-traditional treatment age) in schoolchildren in the Republic of Ireland (henceforth Ireland) and Northern Ireland (NI), UK; populations with broadly similar refractive and genetic profiles but different eye-care systems.

DESIGN

This is a population-based observational study of amblyopia and refractive error.

SETTING

Recruitment and testing in primary and post-primary schools in Ireland and NI.

PARTICIPANTS

Two groups identified through random cluster sampling to represent the underlying population; Ireland 898 participants (12-13 years old) and NI 723 participants (295 aged 9-10 years old, 428 aged 15-16 years old).

MAIN OUTCOME MEASURES

Monocular logMAR visual acuity (presenting and pinhole), refractive error (cycloplegic autorefraction), ocular alignment (cover test) and history of previous eye care. These metrics were used to determine prevalence and type of amblyopia and treatment histories.

RESULTS

Children examined in NI between 2009 and 2011 had a significantly lower amblyopia prevalence than children examined in Ireland between 2016 and 2018 (two-sample test of proportions, p<0.001). Using a criteria of pinhole acuity 0.2logMAR (6/9.5 Snellen) plus an amblyogenic factor, 4 of 295 participants aged 9-10 years old (1.3%, 95% CIs 0.4 to 3.6) and 3 of 428 participants aged 15-16 years old (0.7%, 95%CIs 0.2 to 2.2) were identified in NI. The corresponding numbers in Ireland were 40 of 898 participants aged 12-13 years old (4.5%, 95% CI 3.2 to 6.1). In NI strabismic amblyopia was the most prevalent type of persistent amblyopia, whereas anisometropic was predominant in Ireland. In Ireland, amblyopia was associated with socioeconomic disadvantage (OR=2.2, 95%CIs 1.4 to 3.6, p=0.002) and poor spectacle compliance (OR 2.5, 95% CIs 2.0 to 3.2, p<0.001).

CONCLUSIONS

Amblyopia prevalence persisting beyond traditional treatment ages was significantly lower among NI children compared with Ireland. Uncorrected anisometropia, compliance with spectacle wear and socioeconomic disadvantage were contributing factors in Ireland. Children without obvious visible eye defects were less likely to access eye care in Ireland, resulting in missed opportunities for intervention where necessary.

The awareness of amblyopia among parents in Saudi Arabia

Purpose

Amblyopia is the most common cause of unilateral visual impairment. This study investigated parents' awareness of amblyopia in different regions of Saudi Arabia.

Methods

This was a cross-sectional population study. The survey consisted of two main sections; the first section contained 13 general background questions, and the second section (10 questions) focused on awareness of amblyopia, routine vision checks and how to raise awareness of amblyopia in the community. The survey was distributed to respondents using email and social media.

Results

The responses of 1649 families were received. Respondents' age range was from 22-62 years (mean ± standard deviation = 33.6 ± 8.7 years). Most respondents had no previous knowledge of amblyopia (1155 participants, 70%), and 313 participants (19%) had no idea if their children had amblyopia. In total, 990 participants (60%) did not visit the eye clinic with their children for a routine eye exam. A total of 495 parents (30%), who were aware of amblyopia, knew of it mainly from eye clinic visits and from Internet websites. A total of 140 respondents reported that their children had amblyopia; 58.3% of those children underwent routine eye examinations once a year, and the rest underwent routine eye examinations twice a year.

Conclusion

The results clearly showed a lack of amblyopia awareness among the Saudi community. This lack of awareness can lead to visual impairment among children. More efficient efforts are urgently needed from health professionals, education centres, the media and social organizations to promote awareness of amblyopia.

Comparison of the CAT-QoL and PedsQLTM instruments in measuring quality of life in amblyopia treatment: preliminary results

Background/Aims: The Child Amblyopia Treatment Questionnaire (CAT-QoL) is a patient-reported outcome measure (PROM), designed to assess the impact of amblyopia treatment. The aim of this study was to compare the psychometric properties of two PROMs; the CAT-QoL instrument and Pediatric Quality of Life Inventory (PedsQL^TM), a generic pediatric PROM. This work was part of a wider project to develop a condition-specific PROM for children with amblyopia. Methods: Three hundred and forty-two participants were recruited in a UK multi-center study. Quality of life data was collected using the CAT-QoL and the PedsQL^TM instruments. The psychometric performance of the CAT-QoL and PedsQL^TM were examined in terms of acceptability, reliability, and validity. Results: Both instruments demonstrated good reliability (CAT-QoL Cronbach's α = 0.793; PedsQL^TM α = 0.872). The convergent validity of the CAT-QoL and PedsQL^TM instruments was tested by comparing the instruments to each other. There was a moderate correlation between the PedsQL^TM and the CAT-QoL scores, and this relationship was statistically significant (r_s = -0.517, p < .000). No statistical significance was found between the level of amblyopia severity and the mean PedsQL^TM score (p = .420). Conclusion: It was possible to assess the impact of amblyopia treatment using the CAT-QoL and PedsQL^TM instruments. The preliminary findings from this are not conclusive, and it is not possible to advocate the use of one questionnaire over another based upon psychometric performance demonstrated here. This may be due to the sample population, as there were limited numbers of participants with severe amblyopia. Both the CAT-QoL and PedsQL^TM instruments were noted to have some issues with ceiling effects at an individual item level. The CAT-QoL and PedsQL^TM were reliable (as determined by Cronbach's alpha). The PedsQL^TM instrument was not able to discriminate between amblyopia severity groups (discriminant validity). Further research is required to formally assess the psychometric properties of the CAT-QoL questionnaire.

Refinement of the Child Amblyopia Treatment Questionnaire (CAT-QoL) using Rasch analysis

Aims or Purpose: The Child Amblyopia Treatment Questionnaire (CAT-QoL) was developed using a "bottom-up" methodological approach. Interviews with children with amblyopia identified items (questions) and response levels to be tested in a draft questionnaire consisting of 11 items (sad, feeling on face, hurt, doing schoolwork, cross, how other children treat you, doing things, worried, upset with family, playing with friends, happy). This study describes the refinement of the descriptive system for the CAT-QoL instrument using the application of Rasch analysis. Methods: A multi-centre pilot study was conducted, and data collected from 342 participants. Participants were asked to self-complete the appropriate treatment version of the CAT-QoL questionnaire socio-demographic and clinical data were collected by the clinician using a standardised proforma. A "measure" of child's health was obtained from the parent by asking how they would rate their child's health over the previous week. Rasch analysis techniques were applied to refine the questionnaire. Rasch was used to examine response categories and collapse item response levels, identify poorly performing items, and explore local dependency of items. Results: A total of 331 subjects were included in the study sample, however only 315 were accepted into the RUMM program as a number of subjects had missing questions responses on the CAT-QoL. RUMM also excluded a further 41 subjects as these demonstrated extreme responses. Disordered response categories were found for each item, requiring adjacent response levels to be combined. This was applied to all items, and the model fit was re-examined. Two items were found to have poor fit (cross and happy) and were removed from the measure and the model fit was re-examined. No statistically significant differential item functioning (DIF) was found for any item, using person factors of age, sex or general health. Two items showed some dependency (worried and upset with family), and the poorer fitting item was subsequently removed (upset with family). This resulted in a refined CAT-QoL instrument that consists of 8-items, each with three-level response scales. Conclusion: The refined CAT-QoL instrument includes the following items: sad, feeling on face, hurt, doing work at school, how other children treat you, doing things, worried and playing with friends. The CAT-QoL can be Rasch scored, with a range of 0-16 where a greater value indicates a worse quality of life (or greater impact of treatment on the individual). The CAT-QoL may be useful in determining how amblyopia treatment affects children, and offers an alternative to generic patient reported outcome measures.

Development of a core outcome set for amblyopia, strabismus and ocular motility disorders: a review to identify outcome measures

BACKGROUND

Core Outcome Sets (COS) are defined as the minimum sets of outcomes that should be measured and reported in all randomised controlled trials to facilitate combination and comparability of research. The aim of this review is to produce an item bank of previously reported outcome measures from published studies in amblyopia, strabismus and ocular motility disorders to initiate the development of COS.

METHODS

A review was conducted to identify articles reporting outcome measures for amblyopia, strabismus and ocular motility disorders. Using systematic methods according to the COMET handbook we searched key electronic bibliographic databases from 1st January 2011 to 27th September 2016 using MESH terms and alternatives indicating the different subtypes of amblyopia, strabismus and ocular motility disorders in relation to treatment outcomes and all synonyms. We included Cochrane reviews, other systematic reviews, controlled trials, non-systematic reviews and retrospective studies. Data was extracted to tabulate demographics of included studies, primary and secondary outcomes, methods of measurement and their time points.

RESULTS

A total of 142 studies were included; 42 in amblyopia, 33 in strabismus, and 68 in ocular motility disorders (one study overlap between amblyopia and strabismus). We identified ten main outcome measure domains for amblyopia, 14 for strabismus, and ten common "visual or motility" outcome measure domains for ocular motility disorders. Within the domains, we found variable nomenclature being used and diversity in methods and timings of measurements.

CONCLUSION

This review highlights discrepancies in outcome measure reporting within published literature for amblyopia, strabismus and ocular motility and it generated an item bank of the most commonly used and reported outcome measures for each of the three conditions from recent literature to start the process of COS development. Consensus among all stakeholders including patients and professionals is recommended to establish a useful COS.

Parenting Stress and Adherence to Occlusion Therapy in the Infant Aphakia Treatment Study: A Secondary Analysis of a Randomized Clinical Trial

Purpose

Using data from the Infant Aphakia Treatment Study, we examined the relationship between adherence to patching and parenting stress.

Methods

Caregivers completed the Parenting Stress Index 3 months after surgery (n = 106), after a visual acuity assessment at 12 months of age (n = 97), and at 4.25 (n = 96) years of age. Patching was reported in quarterly telephone interviews and annual 7-day patching diaries, and averaged across all assessments prior to and in the 6 months following the first stress assessment, and for 6 months before and after the other two stress assessments. The association was assessed using linear regression.

Results

Caregivers reporting the highest stress levels 3 months after surgery (i.e., 75th percentile) subsequently reported approximately three-quarters (0.87, 95% confidence interval -1.3 to -0.34) of an hour a day less patching than caregivers reporting the least stress (i.e., the 25th percentile) after controlling for prior patching and other confounders. The association was in the same direction, but not statistically significant, after the second stress assessment and was not apparent at 4.25 years of age. In contrast to our hypothesis, we did not find evidence that higher levels of patching were associated with subsequent increases in parenting stress.

Conclusions

Three months after surgery, higher levels of parenting stress are associated with poorer adherence to patching, and thus stress may contribute to early adherence to patching.

Translational Relevance

Clinicians may wish to provide support to caregivers exhibiting high levels of stress since it may impact their ability to adhere to prescribed patching.

Prevalence of amblyopia in Bulgaria

Introduction: The purpose of this study was to establish the prevalence of amblyopia in children, aged 4 to 10 years, in Bulgaria, who underwent a complete eye examination.Methods: The study was designed as cross-sectional epidemiological study, and the results were calculated in percentages. A complete ophthalmological examination was performed on 1,675 children, aged 4 to 10 years (mean age 7.7 years), during the period 01 Feb 2017-21 April 2017, in five cities, in the western part of Bulgaria. All children were verbal, none of them had a neurologic deficit or mental development delay and a complete examination was successfully performed. The ophthalmological examination consisted of: autorefractometry (using pediatric autorefractor with infrared photoretinoscopy), visual acuity, best-corrected visual acuity (BCVA) and visual acuity with pinhole occluder, cover/uncover and alternate cover test, Worth four-dot test, stereopsis, biomicroscopy and funds examination. Amblyopia was defined as reduction of the BCVA for near and far distances under 40/60 on one or on both eyes in the absence of any pathology of the eye, excluding a pathology leading to stimulus deprivation amblyopia, and in the presence of an amblyogenic factor.Results: Out of 1,675 children, 42 (2.5%) were diagnosed with amblyopia: 7% had strabismic amblyopia (3), 59% had anisometropic amblyopia (25), 31% had isoametropic amblyopia (13), and 3% deprivation amblyopia (1). Unilateral amblyopia was diagnosed in 73% (27) of the cases and bilateral amblyopia in 27% (15). For 45% (754) of the children, it was their first visit to an ophthalmologist.Conclusions: The prevalence of amblyopia among these patients (2.5%) is correlating well with the expected, based on data from other authors, between 1.5% and 3.5%. The fact that nearly half of the children (45%) have not been examined by an ophthalmologist is, however, alarming. The lack of a national screening program in Bulgaria could be the main reason. Other factors include: insufficient number of pediatric ophthalmologists in the country and the lack of awareness among the parents.

Validation of dynamic random dot stereotests in pediatric vision screening

PURPOSE

Stereo vision tests are widely used in the clinical practice for screening amblyopia and amblyogenic conditions. According to literature, none of these tests seems to be suitable to be used alone as a simple and reliable tool. There has been a growing interest in developing new types of stereo vision tests, with sufficient sensitivity to detect amblyopia. This new generation of assessment tools should be computer based, and their reliability must be statistically warranted. The present study reports the clinical evaluation of a screening system based on random dot stereograms using a tablet as display. Specifically, a dynamic random dot stereotest with binocularly detectable Snellen-E optotype (DRDSE) was used and compared with the Lang II stereotest.

METHODS

A total of 141 children (aged 4-14, mean age 8.9) were examined in a field study at the Department of Ophthalmology, Pécs, Hungary. Inclusion criteria consisted of diagnoses of amblyopia, anisometropia, convergent strabismus, and hyperopia. Children with no ophthalmic pathologies were also enrolled as controls. All subjects went through a regular pediatric ophthalmological examination before proceeding to the DRDSE and Lang II tests.

RESULTS

DRDSE and Lang II tests were compared in terms of sensitivity and specificity for different conditions. DRDSE had a 100% sensitivity both for amblyopia (n = 11) and convergent strabismus (n = 21), as well as a 75% sensitivity for hyperopia (n = 36). However, the performance of DRDSE was not statistically significant when screening for anisometropia. On the other hand, Lang II proved to have 81.8% sensitivity for amblyopia, 80.9% for strabismus, and only 52.8% for hyperopia. The specificity of DRDSE was 61.2% for amblyopia, 67.3% for strabismus, and 68.6% for hyperopia, respectively. Conversely, Lang II showed about 10% better specificity, 73.8% for amblyopia, 79.2% for strabismus, and 77.9% for hyperopia.

CONCLUSIONS

The DRDSE test has a better sensitivity for the detection of conditions such as amblyopia or convergent strabismus compared with Lang II, although with slightly lower specificity. If the specificity could be further improved by optimization of the stimulus parameters, while keeping the sensitivity high, DRDSE would be a promising stereo vision test for screening of amblyopia.

Global and regional estimates of prevalence of amblyopia: A systematic review and meta-analysis

Background: Amblyopia is one of the most important causes of vision impairment in the world, especially in children. Although its prevalence varies in different parts of the world, no study has evaluated its prevalence in different geographical regions comprehensively. The aim of the present study was to provide global and regional estimates of the prevalence of amblyopia in different age groups via a systematic search.Methods: In this study, international databases, including Embase, Scopus, PubMed, Web of Science, and other relevant databases, were searched systematically to find articles on the prevalence of amblyopia in different age groups published in English. The prevalence and 95% CI were calculated using binomial distribution. The Cochran's Q-test and I² statistic were applied to assess heterogeneity, a random-effects model was used to estimate the pooled prevalence, and a meta-regression method was utilized to investigate the factors affecting heterogeneity between studies.Results: Of 1252 studies, 73 studies were included in the analysis (sample volume: 530,252). Most of these studies (n = 25) were conducted in the WHO-Western Pacific Regional Office. The pooled prevalence estimate of amblyopia was 1.75% (95% CI: 1.62-1.88), with the highest estimate in European Regional Office (3.67%, 95% CI: 2.89-4.45) and the lowest in African Regional Office (0.51%, 95% CI: 0.24-0.78). The most common cause of amblyopia was anisometropia (61.64%). The I² heterogeneity was 98% (p < 0.001). According to the results of univariate meta-regression, the variables of WHO region (b: 0.566, p < 0.001), sample size (b: -0.284 × 10^-4, p: 0.025), and criteria for definition of amblyopia (b: -0.292, p: 0.010) had a significant effect on heterogeneity between studies, while age group, publication date, and cause of amblyopia had no significant effect on heterogeneity.Conclusion: The prevalence of amblyopia varies in different parts of the world, with the highest prevalence in European countries. Geographical location and criteria for definition of amblyopia are among factors contributing to the difference across the world. The results of this study can help stakeholders to design health programs, especially health interventions and amblyopia screening programs.

A complete investigation of monocular and binocular functions in clinically treated amblyopia

The gold standard of a successful amblyopia treatment is full recovery of visual acuity (VA) in the amblyopic eye, but there has been no systematic study on both monocular and binocular visual functions. In this research, we aimed to quantify visual qualities with a variety of perceptual tasks in subjects with treated amblyopia. We found near stereoacuity and pAE dominance in binocular rivalry in "treated" amblyopia were largely comparable to those of normal subjects. CSF of the pAE remained deficient in high spatial frequencies. The binocular contrast summation ratio is significantly lower than normal standard. The interocular balance point is 34%, indicating that contrast in pAE is much less effective as the same contrast in pFE in binocular phase combination. Although VA, stereoacuity and binocular rivalry at low spatial frequency in treated amblyopes were normal or nearly normal, the pAE remained "lazy" in high frequency domain, binocular contrast summation, and interocular phase combination. Our results suggest that structured monocular and binocular training are necessary to fully recover deficient functions in amblyopia.