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Clinical & Experimental Optometry Jul 2018Despite evidence that amblyopia can often be treated by optical treatment alone, many practitioners still do not use an optical-correction-only phase in amblyopia... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Despite evidence that amblyopia can often be treated by optical treatment alone, many practitioners still do not use an optical-correction-only phase in amblyopia treatment and some investigators omit this important step in their research. This paper aims to systematically review the evidence for the optical treatment of strabismic, refractive and combined-mechanism amblyopia and to quantify the evidence via a meta-analysis.
METHODS
A search of online databases MEDLINE, EMBASE, PsycInfo, the Cochrane Library, and bibliographies of review papers, along with subsequent personal communication, resulted in 29 papers that met our inclusion criteria, with 20 providing sufficient data for the calculation of effect sizes. A meta-analysis was performed to determine effect sizes and the heterogeneity thereof. Meta-regression was used to evaluate the contribution of the possible moderating factors of age, duration of optical correction, and initial visual acuity to the heterogeneity of the studies. In addition, effect sizes were analysed in subgroups based on amblyopia aetiology, that is refractive or strabismic or combined, and also in the fellow eyes.
RESULTS
No evidence of publication bias in the included studies was found using a Galbraith plot. Optical treatment of amblyopia resulted in a large positive effect size of 1.07 (±0.49, 95 per cent confidence limits) on visual acuity, although the heterogeneity was significant (Q = 597.05, I = 96.65 per cent, p < 0.0001). Meta-regression indicated that effect sizes significantly decreased with age, increased with treatment duration, and that better initial acuity was associated with higher effect sizes.
CONCLUSION
Effect sizes were always moderate to large, whether participants were younger or older children, or whether the aetiology was refractive or strabismic. Thus, optical treatment of amblyopia should be considered prior to other treatment in those with refractive error. Improved acuity before initiating other treatment would presumably make occlusion or penalisation less onerous and may improve compliance with further treatment.
Topics: Amblyopia; Child, Preschool; Eyeglasses; Humans; Infant; Refraction, Ocular; Vision Tests; Visual Acuity
PubMed: 29392811
DOI: 10.1111/cxo.12657 -
Trials Apr 2022Aniseikonia represents a potential barrier to neuroplasticity which may limit visual outcomes in children with anisometropic amblyopia. Full correction of refractive...
BACKGROUND
Aniseikonia represents a potential barrier to neuroplasticity which may limit visual outcomes in children with anisometropic amblyopia. Full correction of refractive error is the first step in standard amblyopia treatment, which corrects for image focus but neglects image size differences.
METHODS
The MAGNIFY study is a double-masked, randomised clinical trial investigating the effectiveness of aniseikonia correcting lenses in children at first diagnosis of significant anisometropia. We hypothesis that aniseikonia correction lenses will improve image clarity and reduce the retinal size differences producing better visual acuity and stereoacuity improvements after 15 weeks of optical treatment for children with anisometropia. Eligible children will be randomly allocated to the treatment group (aniseikonia-correcting spectacle lenses) or control group (standard spectacle lenses). Visual acuity and binocular functions will be assessed every 5 weeks during the 15-week optical treatment phase according to standard amblyopia treatment protocol.
DISCUSSION
It is possible that correcting aniseikonia along with anisometropia at first diagnosis will promote binocularity as well as increase spectacle adherence by reducing visual discomfort, improving optical treatment outcomes. This could then reduce the need for additional amblyopia treatment such as patching or atropine, reducing the burden on hospital eye departments and potentially improving visual outcomes for children with amblyopia.
TRIAL REGISTRATION
Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12620000061932 . Registered on 24 January 2020. Protocol 15th November 2019, version one.
Topics: Amblyopia; Aniseikonia; Anisometropia; Australia; Child; Humans; Neuronal Plasticity; Randomized Controlled Trials as Topic
PubMed: 35478070
DOI: 10.1186/s13063-022-06159-2 -
The British Journal of Ophthalmology Oct 1996
Topics: Amblyopia; Anisometropia; Humans
PubMed: 8976692
DOI: 10.1136/bjo.80.10.857 -
Translational Vision Science &... May 2024This study aimed to investigate the possible relationship between retinal vascular abnormalities and amblyopia by analyzing vascular structures of fundus images. (Observational Study)
Observational Study
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.
Topics: Humans; Amblyopia; Female; Male; Retinal Vessels; Visual Acuity; Algorithms; Adult; Young Adult; Adolescent; Child; Fractals; Microvascular Density
PubMed: 38780954
DOI: 10.1167/tvst.13.5.21 -
Quarterly Bulletin. Northwestern... 1960
Topics: Amblyopia; Conversion Disorder; Humans; Hysteria
PubMed: 14420680
DOI: No ID Found -
Clinical & Experimental Optometry Jul 2018Many patient-reported outcome measures (PROMs) have been developed and/or used to measure the impact of amblyopia and strabismus on quality of life (QoL). Identifying...
BACKGROUND
Many patient-reported outcome measures (PROMs) have been developed and/or used to measure the impact of amblyopia and strabismus on quality of life (QoL). Identifying the one with superior quality is important for evaluating the effectiveness of novel therapy for amblyopia and for directing improved clinical decision-making in adults considering strabismic surgery. Therefore, the aim of this review is to identify all PROMs previously developed/used to study the impact of amblyopia and/or strabismus on QoL and to appraise the quality and comprehensiveness of content of the disease-specific instruments.
METHODS
A systematic search was carried out in the electronic databases of PubMed, Cochrane, Web of Science and PsycINFO. The quality of content and measurement properties of all the disease-specific instruments were assessed using established quality standards. Further, the content of the instruments were examined for comprehensiveness by categorising each item across the eight ophthalmic QoL domains (activity limitation, concerns, emotional well-being, social well-being, economic, convenience, symptoms and mobility).
RESULTS
Seventy-one PROMs were identified, out of which 32 were amblyopia- and/or strabismus-specific. Out of all the disease-specific instruments, just four have been subjected to modern psychometric tests and only the adult strabismus questionnaire (AS-20) demonstrated good measurement properties. Most of the amblyopia-specific instruments measured the impact of the treatment of amblyopia on children, while most of the strabismus-specific instruments measured concerns related to appearance and treatment outcome in adults. All instruments have gaps in their content and failed to address QoL comprehensively.
CONCLUSION
All the existing amblyopia- and/or strabismus-specific instruments fall short of desired quality and/or comprehensiveness of content. The review identifies the need for developing an instrument with superior quality and discusses potential directions of future research.
Topics: Amblyopia; Databases, Factual; Humans; Patient Reported Outcome Measures; Psychometrics; Quality of Life; Strabismus; Surveys and Questionnaires
PubMed: 28636173
DOI: 10.1111/cxo.12553 -
Indian Journal of Ophthalmology Jan 2021To study the effectiveness of part-time occlusion (PTO) in different types of amblyopia in Indian population.
PURPOSE
To study the effectiveness of part-time occlusion (PTO) in different types of amblyopia in Indian population.
METHODS
Prospective case series of consecutive cases of amblyopia from a tertiary care center were subjected to PTO of the better eye and monitored periodically for 6 months. Those who failed to improve by 6 months were shifted to full-time occlusion of the better eye and followed for a further 3 months.
RESULTS
175 eyes of 175 patients with amblyopia underwent PTO for 6 months. The mean age of the patients was 10.47 ± 4.69 years (range: 3-26 years). Major subgroups included 94 eyes with strabismic amblyopia and 70 with anisometropic amblyopia. Overall, 168 (96%) children benefited from PTO (improvement being defined as a gain of at least one line of Snellen's visual acuity). The improvement rates for strabismic amblyopes (97.9%) was significantly more than anisometropia (94.3%); P = 0.027. Of the seven patients not responding to PTO, six did not benefit even after full-time patching.
CONCLUSION
PTO is a viable and effective modality of management of amblyopia in Indian patients. Strabismic amblyopia was the commonest and responded best to the occlusion therapy in our cohort.
Topics: Adolescent; Adult; Amblyopia; Anisometropia; Child; Child, Preschool; Humans; Prospective Studies; Sensory Deprivation; Strabismus; Treatment Outcome; Young Adult
PubMed: 33323591
DOI: 10.4103/ijo.IJO_1439_19 -
Medicine Nov 2020To compare distant visual acuity (DVA) and near visual acuity (NVA) in amblyopia and evaluate if NVA can be used to diagnose amblyopia.A retrospective study was...
To compare distant visual acuity (DVA) and near visual acuity (NVA) in amblyopia and evaluate if NVA can be used to diagnose amblyopia.A retrospective study was performed on 73 patients diagnosed with amblyopia based on DVA, by measuring their NVA and comparing the DVA and NVA. The NVA was measured by Snellen chart at 30 cm and the DVA was measured by Dr Hahn vision test chart at 5m. The patients' age, type of amblyopia, spherical equivalent, the difference between spherical equivalent and the fellow eye spherical equivalent spherical, and prism diopter (PD) were evaluated and their relationship with the difference between the DVA and NVA was analyzed.The NVA was significantly better than the DVA in amblyopia (P = .000). The difference between the DVA and NVA was not significantly related to the type of amblyopia (P = .600) or the patients' age(P = .351). Also, the difference between the DVA and NVA was not significantly affected by the spherical equivalent (P = .425) or the difference between spherical equivalent and the fellow eye spherical equivalent (P = .212) in anisometropia amblyopia, and also not by the PD (P = .882) in strabismus amblyopia.In amblyopes, the NVA was better than the DVA before amblyopia treatment. The difference between the DVA and NVA was not affected by age, type of amblyopia, spherical equivalent, the difference between spherical equivalent and the fellow eye spherical equivalent spherical, or PD. Therefore, it should be taken into consideration that NVA could underestimate the severity of amblyopia and affect the accuracy at diagnosing amblyopia.
Topics: Amblyopia; Anisometropia; Child; Diagnostic Techniques, Ophthalmological; Dimensional Measurement Accuracy; Early Diagnosis; Female; Humans; Male; Severity of Illness Index; Strabismus; Visual Acuity
PubMed: 33181679
DOI: 10.1097/MD.0000000000023111 -
Value in Health : the Journal of the... Nov 2021This study aimed to investigate associations between persisting amblyopia into adulthood and its "real-life" impacts and inform the current debate about the value of...
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.
Topics: Adult; Aged; Amblyopia; Biological Specimen Banks; Databases, Factual; Educational Status; Female; Health Status; Humans; Male; Middle Aged; Personal Satisfaction; Social Class; United Kingdom
PubMed: 34711360
DOI: 10.1016/j.jval.2021.05.010 -
Translational Vision Science &... Apr 2022Amblyopia is a major health problem with an estimated 2% to 4% of the population affected. Screening combined with corrective measures, such as correction of refractive...
PURPOSE
Amblyopia is a major health problem with an estimated 2% to 4% of the population affected. Screening combined with corrective measures, such as correction of refractive error and occlusion of the dominant eye, could reduce this prevalence. A new pediatric vision scanner, the blinq (Rebion, Boston, MA), studies the foveolar quality of fixation of each eye during binocular viewing. Based on the initial premise that poor quality foveolar or non-foveolar fixation is indicative of strabismus and, potentially of amblyopia, this study evaluates the effectiveness of the blinq screening device in detecting these two conditions compared to a standard ophthalmic examination (Gold Standard) based on the recommendations of the American Association for Pediatric Ophthalmology and Strabismus.
MATERIAL AND METHODS
A prospective study was performed on a total of 101 children between 2 and 8 years of age. These children were offered a test by the blinq screening device before a standard ophthalmological examination in the ophthalmology department of the Erasmus Hospital in Brussels, Belgium. The two tests were then compared.
RESULTS
In a pediatric population heightened with amblyopia and strabismus (prevalence of 33.4%) and based on the Gold Standard Examination, the blinq device showed a specificity of 73.1% (95% confidence interval [CI] = 60.9%-83.2%) with a sensitivity of 91.2% (95% CI = 76.3%-98.1) to detect these conditions. The positive and negative predictive values were 63.3% (95% CI = 53.4%-72.2%) and 94.2% (95% CI = 84.6%-98%) respectively. The positive likelihood ratio (LR+) was 3.39 (95% CI = 2.26-5.11) for a negative likelihood ratio of 0.12 (95% CI = 0.04-0.36).
CONCLUSIONS
The blinq device has good sensitivity, but insufficient specificity to be used alone in the first line of screening. Whereas other devices on the market detect risk factors that may lead to amblyopia, the blinq pediatric vision scanner detects poor foveolar fixation and strabismus, giving it a potential advantage in sensitivity to directly detect strabismus, including microstrabismus. The blinq does not detect refractive abnormalities, however, and will therefore need to be improved in the future to be used alone in pediatric vision screening.
TRANSLATIONAL RELEVANCE
The blinq device detects visual axis alignment abnormalities with potential impact in the early detection of strabismus and subsequent associated amblyopia.
Topics: Amblyopia; Child; Humans; Prospective Studies; Sensitivity and Specificity; Strabismus; Vision Screening
PubMed: 35416948
DOI: 10.1167/tvst.11.4.10