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Graefe's Archive For Clinical and... Feb 2024To investigate the effects of Cambridge Stimulator with grating element stimulation on visual acuity (VA), grating acuity (GA), and contrast sensitivity (CS) in patients... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
To investigate the effects of Cambridge Stimulator with grating element stimulation on visual acuity (VA), grating acuity (GA), and contrast sensitivity (CS) in patients with amblyopia.
METHODS
Three electronic databases (PubMed, Embase, and Cochrane Library) were searched for studies published from January 1970 to November 2022. The searched studies were reviewed and extracted independently by two authors. The included studies were evaluated by the Cochrane risk of bias. A meta-analysis calculating Hedges' g effect-size metric with 95% confidence intervals using random-effects DerSimonian-Laird model was employed. Heterogeneity was estimated using I statistics. Outcomes of interest included VA, GA, and CS.
RESULTS
A total of 1221 studies were identified. Twenty-four studies including 900 subjects met the inclusion criteria. The outcome measure of all visual indexes (VA: Hedges' g of - 0.43, 95% CI = - 0.81 to - 0.05, I = 86%, p = 0.02; GA: Hedges' g of 3.79, 95% CI = 1.05 to 6.54, I = 98%, p = 0.01; CS: Hedges' g of 0.64, 95% CI = 0.19 to 1.09, I = 41%, p = 0.00) significantly favored in the grating group.
CONCLUSIONS
Grating stimulation may be a positive help for visual functions in patients with amblyopia. The effects of grating stimulation on VA and CS appear to be opposite. This study is registered with www.crd.york.ac.uk/prospero/ (CRD42022366259).
Topics: Humans; Amblyopia; Visual Acuity; Contrast Sensitivity; Databases, Factual
PubMed: 37306731
DOI: 10.1007/s00417-023-06142-w -
Neural Regeneration Research Nov 2023Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention. Previous clinical and neuroimaging...
Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention. Previous clinical and neuroimaging studies have suggested that the neural mechanisms underlying strabismic amblyopia and anisometropic amblyopia may be different. Therefore, we performed a systematic review of magnetic resonance imaging studies investigating brain alterations in patients with these two subtypes of amblyopia; this study is registered with PROSPERO (registration ID: CRD42022349191). We searched three online databases (PubMed, EMBASE, and Web of Science) from inception to April 1, 2022; 39 studies with 633 patients (324 patients with anisometropic amblyopia and 309 patients with strabismic amblyopia) and 580 healthy controls met the inclusion criteria (e.g., case-control designed, peer-reviewed articles) and were included in this review. These studies highlighted that both strabismic amblyopia and anisometropic amblyopia patients showed reduced activation and distorted topological cortical activated maps in the striate and extrastriate cortices during task-based functional magnetic resonance imaging with spatial-frequency stimulus and retinotopic representations, respectively; these may have arisen from abnormal visual experiences. Compensations for amblyopia that are reflected in enhanced spontaneous brain function have been reported in the early visual cortices in the resting state, as well as reduced functional connectivity in the dorsal pathway and structural connections in the ventral pathway in both anisometropic amblyopia and strabismic amblyopia patients. The shared dysfunction of anisometropic amblyopia and strabismic amblyopia patients, relative to controls, is also characterized by reduced spontaneous brain activity in the oculomotor cortex, mainly involving the frontal and parietal eye fields and the cerebellum; this may underlie the neural mechanisms of fixation instability and anomalous saccades in amblyopia. With regards to specific alterations of the two forms of amblyopia, anisometropic amblyopia patients suffer more microstructural impairments in the precortical pathway than strabismic amblyopia patients, as reflected by diffusion tensor imaging, and more significant dysfunction and structural loss in the ventral pathway. Strabismic amblyopia patients experience more attenuation of activation in the extrastriate cortex than in the striate cortex when compared to anisometropic amblyopia patients. Finally, brain structural magnetic resonance imaging alterations tend to be lateralized in the adult anisometropic amblyopia patients, and the patterns of brain alterations are more limited in amblyopic adults than in children. In conclusion, magnetic resonance imaging studies provide important insights into the brain alterations underlying the pathophysiology of amblyopia and demonstrate common and specific alterations in anisometropic amblyopia and strabismic amblyopia patients; these alterations may improve our understanding of the neural mechanisms underlying amblyopia.
PubMed: 37282452
DOI: 10.4103/1673-5374.371349 -
Frontiers in Public Health 2023Virtual Reality (VR) has emerged as a new safe and efficient tool for the rehabilitation of many childhood and adulthood illnesses. VR-based therapies have the potential...
Virtual Reality (VR) has emerged as a new safe and efficient tool for the rehabilitation of many childhood and adulthood illnesses. VR-based therapies have the potential to improve both motor and functional skills in a wide range of age groups through cortical reorganization and the activation of various neuronal connections. Recently, the potential for using serious VR-based games that combine perceptual learning and dichoptic stimulation has been explored for the rehabilitation of ophthalmological and neurological disorders. In ophthalmology, several clinical studies have demonstrated the ability to use VR training to enhance stereopsis, contrast sensitivity, and visual acuity. The use of VR technology provides a significant advantage in training each eye individually without requiring occlusion or penalty. In neurological disorders, the majority of patients undergo recurrent episodes (relapses) of neurological impairment, however, in a few cases (60-80%), the illness progresses over time and becomes chronic, consequential in cumulated motor disability and cognitive deficits. Current research on memory restoration has been spurred by theories about brain plasticity and findings concerning the nervous system's capacity to reconstruct cellular synapses as a result of interaction with enriched environments. Therefore, the use of VR training can play an important role in the improvement of cognitive function and motor disability. Although there are several reviews in the community employing relevant Artificial Intelligence in healthcare, VR has not yet been thoroughly examined in this regard. In this systematic review, we examine the key ideas of VR-based training for prevention and control measurements in ocular diseases such as Myopia, Amblyopia, Presbyopia, and Age-related Macular Degeneration (AMD), and neurological disorders such as Alzheimer, Multiple Sclerosis (MS) Epilepsy and Autism spectrum disorder. This review highlights the fundamentals of VR technologies regarding their clinical research in healthcare. Moreover, these findings will raise community awareness of using VR training and help researchers to learn new techniques to prevent and cure different diseases. We further discuss the current challenges of using VR devices, as well as the future prospects of human training.
Topics: Humans; Child; Artificial Intelligence; Autism Spectrum Disorder; Disabled Persons; Motor Disorders; Virtual Reality; Nervous System Diseases
PubMed: 37033028
DOI: 10.3389/fpubh.2023.1143947 -
Journal of AAPOS : the Official... Apr 2023Economic evaluations in health care quantitatively compare interventions using cost and outcomes data. These evaluations can aid in the adoption of new surgical or... (Review)
Review
BACKGROUND
Economic evaluations in health care quantitatively compare interventions using cost and outcomes data. These evaluations can aid in the adoption of new surgical or medical treatments and inform policy decisions regarding healthcare spending. Several common types of economic analysis exist (cost-benefit, cost-analysis, cost-effectiveness, and cost-utility). We review all English-language economic evaluations in strabismus surgery and pediatric ophthalmology.
METHODS
An electronic literature search of the PubMed and Health Economic Evaluations databases was conducted. Two reviewers independently reviewed the search string yield and assessed articles against inclusion and exclusion criteria. Outcome measures included journal of publication, year of publication, domain of ophthalmology, region/country of study, and type of economic evaluation.
RESULTS
We identified 62 articles. Cost-utility studies comprised 30% of evaluations. The most studied domain was retinopathy of prematurity (33%), followed by amblyopia and vision screening (24%) and cataracts (14%). The Journal of the American Association for Pediatric Ophthalmology and Strabismus published the most economic evaluations (15%) followed by Ophthalmology and Pediatrics. The number of published economic evaluations did not increase over time.
CONCLUSIONS
Economic evaluations in pediatric ophthalmology and strabismus have not increased over time. A minority (30%) of studies used cost utility-analysis, limiting comparisons to other domains of medicine. This suggests the need to alert pediatric ophthalmologists to the benefits of economic analysis, and cost-utility methodology specifically, to better inform and influence policy decisions regarding healthcare spending.
Topics: Child; Humans; Infant, Newborn; Amblyopia; Cost-Benefit Analysis; Delivery of Health Care; Ophthalmology; Strabismus
PubMed: 36940859
DOI: 10.1016/j.jaapos.2022.12.005 -
Ophthalmic Research 2023The performance of optical coherence tomography angiography (OCTA) in macular microvasculature of patients with amblyopia has been widely studied, but these studies have... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The performance of optical coherence tomography angiography (OCTA) in macular microvasculature of patients with amblyopia has been widely studied, but these studies have yielded different and controversial results.
OBJECTIVES
The aim of this study is to investigate retinal microvascular features in patients with amblyopia undergoing OCTA.
METHODS
PubMed, Embase, and Web of Science were searched for published articles comparing the retinal microvascular features between individuals with amblyopia and controls until April 2022. The mean difference with a 95% confidence interval was used to assess continuous variables.
RESULTS
The analysis included 17 studies. The whole vessel density of the superficial capillary plexus (SCPVD) was lower in amblyopic eyes (AE) than in normal eyes (NE) in 3 × 3 mm2 scans, while the perifoveal vessel density of superficial and deep capillary plexus was lower in 6 × 6 mm2 scans. The whole, parafoveal vessel density of deep capillary plexus (DCPVD) and parafoveal SCPVD were lower in both scans. The comparison between AE and fellow eyes (FE) revealed no statistical difference in all quadrants except the parafoveal and perifoveal SCPVD and the foveal DCPVD. Additionally, SCPVD in all quadrants except the fovea and DCPVD in all quadrants except the parafoveal were higher in FE compared to NE. No significant difference was found in the foveal avascular area between AE and NE, AE and FE, or NE and FE.
CONCLUSIONS
The retinal vessel density of superficial and deep capillary plexus in AE and FE was lower than in NE, and differences were more likely discovered using 6 × 6 mm2 scans. Consequently, OCTA might be explored as a diagnostic tool to identify and monitor patients with amblyopia.
Topics: Humans; Amblyopia; Tomography, Optical Coherence; Fluorescein Angiography; Visual Acuity; Cross-Sectional Studies; Retinal Vessels
PubMed: 36917963
DOI: 10.1159/000529857 -
Eye (London, England) Sep 2023Amblyopia is an important public health concern. While home-based screening may present an effective solution, this has not been rigorously assessed in a systematic... (Review)
Review
Amblyopia is an important public health concern. While home-based screening may present an effective solution, this has not been rigorously assessed in a systematic review. A systematic review was performed using Ovid MEDLINE, PubMed, The Cochrane Library, Embase, Web of Science Core Collection, and Clinicaltrials.gov. All studies reporting the diagnostic accuracy of home-based screening tools for amblyopia among children were included. Studies involving orthoptist or ophthalmologist-led screening and adult subjects were excluded. The main outcome measure was the diagnostic accuracy expressed as sensitivity and specificity. Among 3670 studies identified, 28 were eligible for inclusion in our systematic review. The age range of patients were less than 1 month to 16 years old. 7 studies used internet-based tools, 16 used smartphone/tablet applications, 3 used digital cameras, and 3 used home-based questionnaires and visual acuity tools. All studies included a reference standard except one, which was a longitudinal study. 21 studies had full ophthalmological examination whilst 6 studies had validated visual acuity measurement tools as gold standards. Of the 27 studies which compared against a reference test, only 25 studies reported sensitivity and specificity values. Using the QUADAS-2 tool, 50% of studies were deemed to have applicability concern due to patient selection from tertiary centres and unclear methods for recruitment. There is a need to improve the quality of diagnostic accuracy studies, standardise thresholds for detecting amblyopia, and ensure consistent reporting of results. Further research is needed to evaluate the suitability of these tools for amblyopia screening.
Topics: Adult; Child; Humans; Infant; Amblyopia; Longitudinal Studies; Sensitivity and Specificity; Physical Examination
PubMed: 36828959
DOI: 10.1038/s41433-023-02412-3 -
Strabismus Mar 2023The objective of this review was to estimate the prevalence of strabismus and amblyopia in Africa. A systematic online literature search was conducted for articles on... (Meta-Analysis)
Meta-Analysis
The objective of this review was to estimate the prevalence of strabismus and amblyopia in Africa. A systematic online literature search was conducted for articles on strabismus and amblyopia in Africa. Meta-analysis was performed, using the Freeman-Tukey double arcsine transformation, to estimate the prevalence of strabismus and amblyopia in Africa. Subgroup analyses were conducted according to age, gender, study year, and type of amblyopia. Meta-regression was used to evaluate the influence of predetermined factors on the prevalence of amblyopia. 8 (1 population-based & 7 school-based) and 21 (3 population-based & 18 school-based) studies on strabismus and amblyopia with sample sizes of 22,355 and 46,841, respectively, were included in the review. Overall prevalence of strabismus in Africa was estimated to be 0.8% (95% CI: 0.4% - 1.4%); exotropia was 0.2% (95% CI: 0.1% - 0.5%) and esotropia was 0.5% (95% CI: 0.1% - 1.2%). Overall prevalence of amblyopia was estimated to be 0.6% (95% CI: 0.3% - 0.9%); refractive and strabismic amblyopia were 1.1% (95% CI: 0.2% - 2.5%) and 0.4% (95% CI: 0.2% - 0.6%), respectively. Prevalence estimate of amblyopia in males was 1.8% (95% CI: 0.7% - 3.3%) and in females was 1.3% (95% CI: 0.4% - 2.6%). There was a significant association between the prevalence of amblyopia and the type of amblyopia (p = .007) and the study year (p = .006). Although there appears to be a relatively low prevalence of strabismus and amblyopia in Africa, there is a dearth of well-designed population-based studies on strabismus and amblyopia in Africa, resulting in the lack of epidemiological information on strabismus and amblyopia within the general African population. Information about the prevalence of strabismus and amblyopia across Africa can inform policy making and design and implementation of public health intervention program.
Topics: Male; Female; Humans; Amblyopia; Visual Acuity; Strabismus; Esotropia; Prevalence; Africa
PubMed: 36576233
DOI: 10.1080/09273972.2022.2157023 -
Frontiers in Psychology 2022If an individual has been blind since birth due to a treatable eye condition, ocular treatment is urgent. Even a brief period of visual deprivation can alter the...
PURPOSE
If an individual has been blind since birth due to a treatable eye condition, ocular treatment is urgent. Even a brief period of visual deprivation can alter the development of the visual system. The goal of our structured scoping review was to understand how we might better support children with delayed access to ocular treatment for blinding conditions.
METHOD
We searched MEDLINE, Embase and Global Health for peer-reviewed publications that described the impact of early (within the first year) and extended (lasting at least 2 years) bilateral visual deprivation.
RESULTS
Of 551 reports independently screened by two authors, 42 studies met our inclusion criteria. Synthesizing extracted data revealed several trends. The data suggests persistent deficits in visual acuity, contrast sensitivity, global motion, and visual-motor integration, and suspected concerns for understanding complex objects and faces. There is evidence for resilience in color perception, understanding of simple shapes, discriminating between a face and non-face, and the perception of biological motion. There is currently insufficient data about specific (re)habilitation strategies to update low vision services, but there are several insights to guide future research in this domain.
CONCLUSION
This summary will help guide the research and services provision to help children learn to see after early and extended blindness.
PubMed: 36389599
DOI: 10.3389/fpsyg.2022.954328 -
Graefe's Archive For Clinical and... May 2023Amblyopia is a neurodevelopmental disorder characterized by functional deficits in the visual cortex. Functional magnetic resonance imaging (fMRI) is the most commonly... (Review)
Review
Amblyopia is a neurodevelopmental disorder characterized by functional deficits in the visual cortex. Functional magnetic resonance imaging (fMRI) is the most commonly used neuroimaging technique for investigating amblyopia. Herein, we systematically searched a PubMed database from inception to December 2021 to highlight the current progress and promises about fMRI technology in amblyopia; amblyopia's neural mechanism, the comparison of different types of amblyopia, and the evaluation of the therapeutic effect were explored. Relevant articles published in English and appropriate cross-references were considered for inclusion, including basic studies, imaging techniques, clinical diagnostic and therapeutic studies, case series, and reviews.
Topics: Humans; Amblyopia; Visual Cortex; Magnetic Resonance Imaging
PubMed: 36282454
DOI: 10.1007/s00417-022-05826-z -
The Cochrane Database of Systematic... Sep 2022Congenital cataracts are lens opacities in one or both eyes of babies or children present at birth. These may cause a reduction in vision severe enough to require... (Review)
Review
BACKGROUND
Congenital cataracts are lens opacities in one or both eyes of babies or children present at birth. These may cause a reduction in vision severe enough to require surgery. Cataracts are proportionally the most treatable cause of visual loss in childhood, and are a particular problem in low-income countries, where early intervention may not be possible. Paediatric cataracts provide different challenges to those in adults. Intense inflammation, amblyopia (vision is obstructed by cataract from birth which prevents normal development of the visual system), posterior capsule opacification and uncertainty about the final trajectory of ocular growth parameters can affect results of treatment. Two options currently considered for children under 2 years of age with bilateral congenital cataracts are: (i) intraocular lens (IOL) implantation; or (ii) leaving a child with primary aphakia (no lens in the eye), necessitating the need for contact lenses or aphakic glasses. Other important considerations regarding surgery include the prevention of visual axis opacification (VAO), glaucoma and the route used to perform lensectomy.
OBJECTIVES
To assess the effectiveness of infant cataract surgery or lensectomy to no surgery for bilateral congenital cataracts in children aged 2 years and under.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL; which contains the Cochrane Eyes and Vision Trials Register; 2022, Issue 1); Ovid MEDLINE; Ovid Embase; the ISRCTN registry; ClinicalTrials.gov and the WHO ICTRP. The date of the search was 25 January 2022.
SELECTION CRITERIA
We included all randomised controlled trials (RCTs) that compared infant cataract surgery or lensectomy to no surgery, in children with bilateral congenital cataracts aged 2 years and younger. This update (of a review published in 2001 and updated in 2006) does not include children over 2 years of age because they have a wider variety of aetiologies, and are therefore managed differently, and have contrasting outcomes.
DATA COLLECTION AND ANALYSIS
We used standard methods expected by Cochrane. Two review authors extracted data independently. We assessed the risk of bias of included studies using RoB 1 and assessed the certainty of the evidence using GRADE.
MAIN RESULTS
We identified three RCTs that met our inclusion criteria with each trial comparing a different aspect of surgical intervention for this condition. The trials included a total of 79 participants under 2 years of age, were conducted in India and follow-up ranged from 1 to 5 years. Study participants and outcome assessors were not masked in these trials. One study (60 children) compared primary IOL implantation with primary aphakia. The results from this study suggest that there may be little or no difference in visual acuity at 5 years comparing children with pseudophakia (mean logMAR 0.50) and aphakia (mean logMAR 0.59) (mean difference (MD) -0.09 logMAR, 95% confidence intervals (CIs) -0.24 to 0.06; 54 participants; very low-certainty evidence), but the evidence is very uncertain. The evidence is very uncertain as to the effect of IOL implantation compared with aphakia on visual axis opacification (VAO) (risk ratio (RR) 1.29, 95% CI 0.23 to 7.13; 54 participants; very low-certainty evidence). The trial investigators did not report on the cases of amblyopia. There was little evidence of a difference betwen the two groups in cases of glaucoma at 5 years follow-up (RR 0.86, 95% CI 0.24 to 3.10; 54 participants; very low-certainty evidence). Cases of retinal detachment and reoperation rates were not reported. The impact of IOL implantation on adverse effects is very uncertain because of the sparse data available: of the children who were pseudophakic, 1/29 needed a trabeculectomy and 8/29 developed posterior synechiae. In comparison, no trabeculectomies were needed in the aphakic group and 2/25 children had posterior synechiae (54 participants; very low-certainty evidence). The second study (14 eyes of 7 children under 2 years of age) compared posterior optic capture of IOL without vitrectomy versus endocapsular implantations with anterior vitrectomy (commonly called 'in-the-bag surgery'). The authors did not report on visual acuity, amblyopia, glaucoma and reoperation rate. They had no cases of VAO in either group. The evidence is very uncertain as to the effect of in-the-bag implantation in children aged under 1 year. There was a higher incidence of inflammatory sequelae: 4/7 in-the-bag implantation eyes and 1/7 in optic capture eyes (P = 0.04, 7 participants; very low-certainty evidence). We graded the certainty of evidence as low or very low for imprecision in all outcomes because their statistical analysis reported that a sample size of 13 was needed in each group to achieve a power of 80%, whereas their subset of children under the age of 1 year had only 7 eyes in each group. The third study (24 eyes of 12 children) compared a transcorneal versus pars plana route using a 25-gauge transconjunctival sutureless vitrectomy system. The evidence is very uncertain as to the effect of the route chosen on the incidence of VAO, with no cases reported at 1 year follow-up in either group. The investigators did not report on visual acuity, amblyopia, glaucoma, retinal detachment and reoperation rate. The pars plana route had the adverse effects of posterior capsule rupture in 2/12 eyes, and 1/12 eyes needing sutures. Conversely, 1/12 eyes operated on by the transcorneal route needed sutures. We graded the outcomes with very low-certainty because of the small sample size and the absence of a priori sample size calculation.
AUTHORS' CONCLUSIONS
There is no high level evidence for the effectiveness of one type of surgery for bilateral congenital cataracts over another, or whether surgery itself is better than primary aphakia. Further RCTs are required to inform modern practice about concerns, including the timing of surgery, age at which surgery should be undertaken, age for implantation of an IOL and development of complications, such as reoperations, glaucoma and retinal detachment. Standardising the methods used to measure visual function, along with objective monitoring of compliance with the use of aphakic glasses/contact lenses would greatly improve the quality of study data and enable more reliable interpretation of outcomes.
Topics: Amblyopia; Aphakia; Capsule Opacification; Child; Child, Preschool; Glaucoma; Humans; Infant; Infant, Newborn; Lens Implantation, Intraocular; Retinal Detachment
PubMed: 36107778
DOI: 10.1002/14651858.CD003171.pub3