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Hernández-Rodríguez CJ, Ferrer-Soldevila P, Artola-Roig A, Piñero DP. Rehabilitation of amblyopia using a digital platform for visual training combined with patching in children: a prospective study. Graefes Arch Clin Exp Ophthalmol 2024; 262:3007-3020. [PMID: 38578335 PMCID: PMC11377642 DOI: 10.1007/s00417-024-06475-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 03/25/2024] [Accepted: 03/28/2024] [Indexed: 04/06/2024] Open
Abstract
PURPOSE To assess the possible benefits of the use of perceptual learning and dichoptic therapy combined with patching in children with amblyopia over the use of only patching. METHODS Quasi-experimental multicentric study including 52 amblyopic children. Patients who improved their visual acuity (VA) by combining spectacles and patching were included in patching group (PG: 20 subjects), whereas those that did not improved with patching performed visual training (perceptual learning + dichoptic therapy) combined with patching, being assigned to the visual treatment group (VT: 32 subjects). Changes in VA, contrast sensitivity (CS), and stereopsis were monitored during a 6-month follow-up in each group. RESULTS Significant improvements in VA were found in both groups at 1 month (p < 0.01). The total improvement of VA was 0.18 ± 0.16 and 0.31 ± 0.35 logMAR in PG and VT groups, respectively (p = 0.317). The Wilcoxon effect size was slightly higher in VT (0.48 vs. 0.54) at 6 months. An enhancement in CS was observed in the amblyopic eye of the VT group for all spatial frequencies at 1 month (p < 0.001). Likewise, the binocular function score also increased significantly in VT group (p = 0.002). A prediction equation of VA improvement at 1 month in VT group was obtained by multiple linear regression analysis (p < 0.001, R2 = 0.747). CONCLUSIONS A combined treatment of visual training and patching is effective for obtaining a predictable improvement of VA, CS, and binocularity in patching-resistant amblyopic children.
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Affiliation(s)
- Carlos J Hernández-Rodríguez
- Group of Optics and Visual Perception, Department of Optics, Pharmacology and Anatomy, University of Alicante, Crta San Vicente del Raspeig S/N 03016, San Vicente del Raspeig, Alicante, Spain
- Clinical Optometry Unit, Department of Ophthalmology, Ribera Virgen de La Caridad Hospital, Cartagena, Spain
| | | | - Alberto Artola-Roig
- Department of Ophthalmology, Vithas Medimar International Hospital, Alicante, Spain
| | - David P Piñero
- Group of Optics and Visual Perception, Department of Optics, Pharmacology and Anatomy, University of Alicante, Crta San Vicente del Raspeig S/N 03016, San Vicente del Raspeig, Alicante, Spain.
- Clinical Optometry Unit, Department of Ophthalmology, Vithas Medimar International Hospital, Alicante, Spain.
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Wygnanski-Jaffe T, Moshkovitz A, Kushner BJ, Belkin M, Yehezkel O. Binocular Home Treatment for Amblyopia: Gains Stable for One Year. Am J Ophthalmol 2024; 262:199-205. [PMID: 38360334 DOI: 10.1016/j.ajo.2024.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 02/03/2024] [Accepted: 02/05/2024] [Indexed: 02/17/2024]
Abstract
PURPOSE To report the long-term outcomes of a noninferiority randomized controlled trial (RCT) with a binocular eye-tracking-based home treatment (CureSight; NovaSight, Ltd.) in patients with amblyopia. DESIGN Prospective, multicenter, nonrandomized, long-term follow-up observational study of an RCT. METHODS Forty-three children 4 to <9 years of age with anisometropic, small-angle strabismic, or mixed-mechanism amblyopia were initially treated for 16 weeks (NCT05185076) with CureSight. In this planned observational follow-up study, 38 patients with no additional amblyopia treatment were evaluated at 12 weeks post-treatment, and 27 were evaluated at 1-year post-treatment. The main outcome measures were visual acuity (VA), stereoacuity, and amblyopia recurrence at 12- and 52-week post-treatment. RESULTS At 12-week post-treatment, improvement in amblyopic eye VA was maintained vs baseline (0.27 ± 0.14 logMAR, P< .0001), with no change vs the end-of-treatment visit (P > .05). At 1 year there was a partial reduction in the amblyopic eye VA gain of 0.085±0.1 logMAR compared to end-of-treatment (P = .001), but the residual gain of 0.20±0.14 logMAR compared to baseline was statistically significant (P < .0001). Gains in stereoacuity and binocular VA were maintained vs baseline at both 12-weeks and 1-year post-treatment (P < .0001), with no change vs end-of-treatment (P > .05). Amblyopia recurrence (a worsening of ≥2 logMAR levels compared with end-of-treatment) occurred in 2/38 patients at 12-weeks post-treatment (5.3%), and in 5/27 patients at 1-year post-treatment (20.4%). CONCLUSIONS VA and stereopsis gains following binocular treatment with CureSight were maintained at 1 year without additional treatment.
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Affiliation(s)
- Tamara Wygnanski-Jaffe
- Goldschleger Eye Institute, Sheba Medical Center (T.W.-J.), Tel Hashomer, Israel; Sackler Faculty of Medicine, Tel-Aviv University (T.W.-J., M.B.), Tel-Aviv, Israel
| | | | - Burton J Kushner
- Department of Ophthalmology and Visual Sciences, University of Wisconsin (B.J.K.), Madison, Wisconsin, USA
| | - Michael Belkin
- Sackler Faculty of Medicine, Tel-Aviv University (T.W.-J., M.B.), Tel-Aviv, Israel; Goldschleger Eye Research Institute, Sheba Medical Center (M.B.), Tel Hashomer, Israel
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Zou L, Zhou C, Hess RF, Zhou J, Min SH. Daily dose-response from short-term monocular deprivation in adult humans. Ophthalmic Physiol Opt 2024; 44:564-575. [PMID: 38317572 DOI: 10.1111/opo.13282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 01/14/2024] [Accepted: 01/21/2024] [Indexed: 02/07/2024]
Abstract
Short-term monocular deprivation (MD) shifts sensory eye balance in favour of the previously deprived eye. The effect of MD on eye balance is significant but brief in adult humans. Recently, researchers and clinicians have attempted to implement MD in clinical settings for adults with impaired binocular vision. Although the effect of MD has been studied in detail in single-session protocols, what is not known is whether the effect of MD on eye balance deteriorates after repeated periods of MD (termed 'perceptual deterioration'). An answer to this question is relevant for two reasons. Firstly, the effect of MD (i.e., dose-response) should not decrease with repeated use if MD is to be used therapeutically (e.g., daily for weeks). Second, it bears upon the question of whether the neural basis of the effects of MD and contrast adaptation, a closely related phenomenon, is the same. The sensory change from contrast adaptation depends on recent experience. If the observer has recently experienced the same adaptation multiple times for consecutive days, then the adaptation effect will be smaller because contrast adaptation exhibits perceptual deterioration, so it is of interest to know if the effects of MD follow suit. This study measured the effect of 2-h MD for seven consecutive days on binocular balance of 15 normally sighted adults. We found that the shift in eye balance from MD stayed consistent, showing no signs of deterioration after subjects experienced multiple periods of MD. This finding shows no loss of effectiveness of repeated daily doses of MD if used therapeutically to rebalance binocular vision in otherwise normal individuals. Furthermore, ocular dominance plasticity, which is the basis of the effects of short-term MD, does not seem to share the property of 'perceptual deterioration' with contrast adaptation, suggesting different neural bases for these two related phenomena.
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Affiliation(s)
- Liying Zou
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Affiliated Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Chenyan Zhou
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Affiliated Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Robert F Hess
- McGill Vision Research, Department of Ophthalmology and Visual Sciences, McGill University, Montreal, Quebec, Canada
| | - Jiawei Zhou
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Affiliated Eye Hospital, Wenzhou Medical University, Wenzhou, China
| | - Seung Hyun Min
- State Key Laboratory of Ophthalmology, Optometry and Visual Science, Affiliated Eye Hospital, Wenzhou Medical University, Wenzhou, China
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Cakir GB, Murray J, Dulaney C, Ghasia F. Multifaceted Interactions of Stereoacuity, Inter-Ocular Suppression, and Fixation Eye Movement Abnormalities in Amblyopia and Strabismus. Invest Ophthalmol Vis Sci 2024; 65:19. [PMID: 38470326 PMCID: PMC10941996 DOI: 10.1167/iovs.65.3.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 02/19/2024] [Indexed: 03/13/2024] Open
Abstract
Purpose Amblyopic and strabismus subjects experience inter-ocular suppression, impaired stereoacuity, and increased fixation instability. The purpose of the study was to investigate factors affecting suppression and stereoacuity and examine their relationship to fixation eye movement (FEM) abnormalities. Methods We recruited 14 controls and 46 amblyopic subjects (anisometropic = 18, strabismic = 14, and mixed = 14) and 11 subjects with strabismus without amblyopia. We utilized the dichoptic motion coherence test to quantify suppression, and stereoacuity was assessed using the Titmus Fly test. We recorded FEMs using high-resolution video-oculography and classified subjects that did not have nystagmus (n = 27) versus those with nystagmus (n = 32; fusion maldevelopment nystagmus [FMN], n = 10) and nystagmus that did not meet the criteria of FMN (n = 20). We also recorded FEMs under dichoptic viewing (DcV) at varied fellow eye (FE) contrasts and computed the amplitude and velocity of the fast and slow FEMs and vergence instability. Results Inter-ocular suppression and stereoacuity deficits were closely correlated with an amblyopic eye (AE), visual acuity, and strabismus angle. Subjects with nystagmus displayed more pronounced stereoacuity deficits than those without nystagmus. Strabismic subjects with and without amblyopia, who demonstrated a fixation switch at 100% FE contrast, had lower inter-ocular suppression than subjects lacking a fixation switch under DcV. Amplitude of fast FEMs and velocity of slow FEMs, and vergence instability were increased as the FE contrast was lowered in both amblyopic and strabismic subjects. Conclusions The current study highlights the intricate relationships between AE visual acuity, eye deviation, and FEM abnormalities on suppression and stereoacuity deficits and underscores the need to evaluate FEM abnormalities while assessing dichoptic treatment outcomes.
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Affiliation(s)
- Gokce Busra Cakir
- Ocular Motility & Vision Neurosciences Laboratory, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Jordan Murray
- Ocular Motility & Vision Neurosciences Laboratory, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Cody Dulaney
- Ocular Motility & Vision Neurosciences Laboratory, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Fatema Ghasia
- Ocular Motility & Vision Neurosciences Laboratory, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
- Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
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Abstract
Neurological insults, such as congenital blindness, deafness, amputation, and stroke, often result in surprising and impressive behavioural changes. Cortical reorganisation, which refers to preserved brain tissue taking on a new functional role, is often invoked to account for these behavioural changes. Here, we revisit many of the classical animal and patient cortical remapping studies that spawned this notion of reorganisation. We highlight empirical, methodological, and conceptual problems that call this notion into doubt. We argue that appeal to the idea of reorganisation is attributable in part to the way that cortical maps are empirically derived. Specifically, cortical maps are often defined based on oversimplified assumptions of 'winner-takes-all', which in turn leads to an erroneous interpretation of what it means when these maps appear to change. Conceptually, remapping is interpreted as a circuit receiving novel input and processing it in a way unrelated to its original function. This implies that neurons are either pluripotent enough to change what they are tuned to or that a circuit can change what it computes. Instead of reorganisation, we argue that remapping is more likely to occur due to potentiation of pre-existing architecture that already has the requisite representational and computational capacity pre-injury. This architecture can be facilitated via Hebbian and homeostatic plasticity mechanisms. Crucially, our revised framework proposes that opportunities for functional change are constrained throughout the lifespan by the underlying structural 'blueprint'. At no period, including early in development, does the cortex offer structural opportunities for functional pluripotency. We conclude that reorganisation as a distinct form of cortical plasticity, ubiquitously evoked with words such as 'take-over'' and 'rewiring', does not exist.
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Affiliation(s)
- Tamar R Makin
- MRC Cognition and Brain Sciences Unit, University of CambridgeCambridgeUnited Kingdom
| | - John W Krakauer
- Department of Neuroscience, Johns Hopkins University School of MedicineBaltimoreUnited States
- Department of Neurology, Johns Hopkins University School of MedicineBaltimoreUnited States
- The Santa Fe InstituteSanta FeUnited States
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Hogan M, DiCostanzo NR, Crowder NA, Fong MF, Duffy KR. Investigation of the efficacy and safety of retinal inactivation as a treatment for amblyopia in cats. Front Neurosci 2023; 17:1167007. [PMID: 37409104 PMCID: PMC10319065 DOI: 10.3389/fnins.2023.1167007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 05/23/2023] [Indexed: 07/07/2023] Open
Abstract
Introduction Deprivation of normal vision early in postnatal development elicits modifications of neural circuitry within the primary visual pathway that can cause a severe and intractable vision impairment (amblyopia). In cats, amblyopia is often modeled with monocular deprivation (MD), a procedure that involves temporarily closing the lids of one eye. Following long-term MD, brief inactivation of the dominant eye's retina can promote recovery from the anatomical and physiological effects of MD. In consideration of retinal inactivation as a viable treatment for amblyopia it is imperative to compare its efficacy against conventional therapy, as well as assess the safety of its administration. Methods In the current study we compared the respective efficacies of retinal inactivation and occlusion of the dominant eye (reverse occlusion) to elicit physiological recovery from a prior long-term MD in cats. Because deprivation of form vision has been associated with development of myopia, we also examined whether ocular axial length or refractive error were altered by a period of retinal inactivation. Results The results of this study demonstrate that after a period of MD, inactivation of the dominant eye for up to 10 days elicited significant recovery of visually-evoked potentials that was superior to the recovery measured after a comparable duration of reverse occlusion. After monocular retinal inactivation, measurements of ocular axial length and refractive error were not significantly altered from their pre-inactivation values. The rate of body weight gain also was not changed during the period of inactivation, indicating that general well-being was not affected. Discussion These results provide evidence that inactivation of the dominant eye after a period of amblyogenic rearing promotes better recovery than eye occlusion, and this recovery was achieved without development of form-deprivation myopia.
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Affiliation(s)
- Mairin Hogan
- Faculty of Health, Clinical Vision Science, Dalhousie University, Halifax, NS, Canada
| | - Nadia R. DiCostanzo
- Faculty of Health, Clinical Vision Science, Dalhousie University, Halifax, NS, Canada
| | - Nathan A. Crowder
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada
| | - Ming-fai Fong
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, United States
| | - Kevin R. Duffy
- Department of Psychology and Neuroscience, Dalhousie University, Halifax, NS, Canada
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Zhu Q, Zhao Q, Liang R, He X, Gao M. Effectiveness of binocular therapy as a complementary treatment of part-time patching in older amblyopic children: a randomized clinical trial. Int Ophthalmol 2023:10.1007/s10792-023-02642-0. [PMID: 36877316 DOI: 10.1007/s10792-023-02642-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 01/19/2023] [Indexed: 03/07/2023]
Abstract
PURPOSE To assess the effectiveness of combined use of stereoscopic 3D video movies and part-time patching in treating older amblyopic children with poor response or compliance to traditional patching treatments and comparing this combined treatment with patching alone. METHODS Thirty-two children aged 5-12 years with amblyopia associated with anisometropia, strabismus, or both were recruited in a randomized clinical trial. Eligible participants were assigned randomly to the combined and patching groups. Here, binocular treatment refers to using the Bangerter filter to blur the fellow eye and subsequently watching a close-up 3D movie with large parallax. The primary outcome was amblyopic eye (AE) best-corrected visual acuity (BCVA) improvement at six weeks. In addition, secondary outcomes included BCVA of AE improvement at three weeks and change of stereoacuity. RESULTS Of 32 participants, mean (SD) age was 6.63 (1.46) years, and 19 (59%) were female. At 6 weeks, mean (SD) amblyopic eye VA improved by 0.17 ± 0.08 logMAR (2-sided 95% CI, 0.13 to 0.22; F = 57.2, p < 0.01) and 0.05 ± 0.04 logMAR (2-sided 95% CI, 0.05 to 0.09; F = 8.73, p = 0.01) in the combined and patching groups, respectively. The difference was statistically significant (mean difference, 0.13 logMAR [1.3 line]; 95% CI, 0.08-0.17 logMAR [0.8-1.7 lines]; t25 = 5.65, p < 0 .01). After treatment, only the combined group had significantly improved stereoacuity, such as binocular function score (median [interquartile range], 2.30 [2.23 to 2.68] vs. 1.69 [1.60 to 2.30] log arcsec; paired, z = -3.53, p < 0.01), and mean stereoacuity gain was 0.47 log arcsec (± 0.22). Changes in other types of stereoacuity were similar. CONCLUSION Our laboratory-based binocular treatment strategy engaged a high level of compliance that led to a substantial gain in visual function after a short period of treatment for older amblyopic children having poor response or compliance to traditional patching treatments. Notably, the improving stereoacuity showed a greater advantage.
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Affiliation(s)
- Qing Zhu
- Department of Ophthalmology, the Second Hospital of Dalian Medical University, Dalian, 116027, China
| | - Qi Zhao
- Department of Ophthalmology, the Second Hospital of Dalian Medical University, Dalian, 116027, China.
| | - Ran Liang
- Department of Ophthalmology, the Second Hospital of Dalian Medical University, Dalian, 116027, China
| | - Xing He
- Department of Ophthalmology, the Second Hospital of Dalian Medical University, Dalian, 116027, China
| | - Mingjun Gao
- Department of Ophthalmology, the Second Hospital of Dalian Medical University, Dalian, 116027, China
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Birch EE, Kelly KR. Amblyopia and the whole child. Prog Retin Eye Res 2023; 93:101168. [PMID: 36736071 PMCID: PMC9998377 DOI: 10.1016/j.preteyeres.2023.101168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 02/04/2023]
Abstract
Amblyopia is a disorder of neurodevelopment that occurs when there is discordant binocular visual experience during the first years of life. While treatments are effective in improving visual acuity, there are significant individual differences in response to treatment that cannot be attributed solely to difference in adherence. In this considerable variability in response to treatment, we argue that treatment outcomes might be optimized by utilizing deep phenotyping of amblyopic deficits to guide alternative treatment choices. In addition, an understanding of the broader knock-on effects of amblyopia on developing visually-guided skills, self-perception, and quality of life will facilitate a whole person healthcare approach to amblyopia.
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Affiliation(s)
- Eileen E Birch
- Pediatric Vision Laboratory, Retina Foundation of the Southwest, 9600 North Central Expressway #200, Dallas, TX, 75225, USA; Department of Ophthalmology, University of Texas Southwestern Medical Center, 5303 Harry Hines Boulevard, Dallas, TX, 75390, USA.
| | - Krista R Kelly
- Department of Ophthalmology, University of Texas Southwestern Medical Center, 5303 Harry Hines Boulevard, Dallas, TX, 75390, USA; Vision and Neurodevelopment Laboratory, Retina Foundation of the Southwest, 9600 North Central Expressway #200, Dallas, TX, 75225, USA.
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Muacevic A, Adler JR. Awareness and Knowledge of Amblyopia: A Cross-Sectional Study Among the Population of Hail City, Saudi Arabia. Cureus 2022; 14:e32194. [PMID: 36505952 PMCID: PMC9728983 DOI: 10.7759/cureus.32194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2022] [Indexed: 12/12/2022] Open
Abstract
Introduction Amblyopia, also known as the lazy eye, is the reduction of the best-corrected visual acuity of one or both eyes that cannot be attributed exclusively to a structural abnormality of the eye. This study investigated the Hail population's awareness of amblyopia. Methods A cross-sectional study was conducted in Hail, Kingdom of Saudi Arabia (KSA), from May to October 2022. Data entry and analysis were done using RStudio (R version 4.1.1). Results This study included 496 of the general population (23.8% males and 76.2% females), and the majority of them had a university degree (65.7%). Of the population, 52.4% knew the definition of amblyopia, 43.4% knew the treatment of amblyopia, and 85.1% knew the importance of checking the child's vision before school to ensure normal development. In 35.7% of the population, the main source of information was the internet and social media. The median knowledge score of participants was 4 (interquartile range (IQR): 3-5) with a minimum of 0 and a maximum of 9. Based on the univariate analysis, participants aged 41 years or older had significantly lower knowledge scores (β = -0.40, 95% confidence interval (CI): -0.81 to -0.99, p = 0.049), whereas respondents with a positive family history of amblyopia had a significantly higher knowledge score (β = 0.32, 95%CI: 0.02 to 0.61, p = 0.034). Conclusions This study assessed the awareness and knowledge of amblyopia among the population in Hail city. According to our data, we found a significantly poor awareness and knowledge compared to other big cities in the same country such as Riyadh and Jeddah. This indicates that knowledge in smaller cities is deficient in enough and accurate sources of knowledge of eye conditions.
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Jia Y, Liu J, Ye Q, Zhang S, Feng L, Xu Z, Zhuang Y, He Y, Zhou Y, Chen X, Yao Y, Jiang R, Thompson B, Li J. Factors predicting regression of visual acuity following successful treatment of anisometropic amblyopia. Front Med (Lausanne) 2022; 9:1013136. [PMID: 36388932 PMCID: PMC9659723 DOI: 10.3389/fmed.2022.1013136] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 10/17/2022] [Indexed: 11/28/2022] Open
Abstract
Objective To identify factors associated with visual acuity regression following successful treatment of anisometropic amblyopia. Design and method This was a retrospective cohort study. Database records for 100 and 61 children with anisometropic amblyopia who met at least one criterion for successful treatment proposed by the Pediatric Eye Disease Investigator Group (PEDIG) and had at least 1 year of follow-up data available after the criterion was met were analyzed. The study sample was split into two groups, those who regressed within 1 year of successful treatment (no longer met any of the PEDIG criteria for successful treatment) and those who did not. A two-step analysis involving a least absolute shrinkage and selection operator (LASSO) regression and a logistic regression were used to identify predictor variables for increased risk of regression. A broad range of clinical, perceptual, and demographic variables were included in the analyses. Results Sixty-eight (42.5%) children regressed within 1 year of successful treatment. Among the 27 predictor variables considered within the statistical modeling process, the three most important for predicting treatment regression were the extent of amblyopic eye visual acuity improvement, age at first hospital visit and sex. Specifically, lower risk of regression was associated with larger amblyopic eye visual acuity improvement with treatment, younger age at initiation of treatment and female sex. Conclusion Patients who received treatment at a younger age and responded well to treatment had a lower risk of treatment regression. This pattern of results suggests that early detection of amblyopia and strategies that enhance treatment adherence may reduce the risk of treatment regression. The higher risk of regression in boys than girls that we observed may reflect known sex differences in brain development and /or sex differences in environment within our sample of children from South China.
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Affiliation(s)
- Yu Jia
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- Centre for Eye and Vision Research, Hong Kong, Hong Kong SAR, China
| | - Jing Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Qingqing Ye
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Shenglan Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Lei Feng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Zixuan Xu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Yijing Zhuang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Yunsi He
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Yusong Zhou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Xiaolan Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Ying Yao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Rengang Jiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Benjamin Thompson
- Centre for Eye and Vision Research, Hong Kong, Hong Kong SAR, China
- School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
- Liggins Institute, University of Auckland, Auckland, New Zealand
- Benjamin Thompson
| | - Jinrong Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
- *Correspondence: Jinrong Li
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Ghasia F, Wang J. Amblyopia and fixation eye movements. J Neurol Sci 2022; 441:120373. [PMID: 36007287 DOI: 10.1016/j.jns.2022.120373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 07/05/2022] [Accepted: 07/31/2022] [Indexed: 11/29/2022]
Abstract
Amblyopia is a neurodevelopmental disorder caused by abnormal visual experience in early life that affects 3-5% of the population. Amblyopia results in a host of monocular and binocular visual afferent function deficits including reduced visual acuity, contrast sensitivity, depth perception, interocular suppression, and efferent function abnormalities such as unstable and inaccurate fixation. Conventional treatments such as patching therapy and newer dichoptic treatments are not always successful as 30-40% of patients experience recurrence/regression of amblyopia. There are numerous review articles focused on visual afferent function deficits and treatment modalities and outcomes in amblyopia. Recently, the advent of high spatial and temporal resolution eye trackers has spurred studies on fixation eye movements (FEMs) in healthy controls and neurologic and ophthalmic disorders. In this focused review, we will summarize studies evaluating FEM abnormalities in amblyopia. We will first describe the common devices and techniques used to quantify fixation abnormalities, and then highlight the importance of systematically evaluating the eye movements under different viewing conditions and describe the parameters crucial in assessing FEM abnormalities in amblyopia. We will summarize the evidence suggesting that FEM abnormalities are not limited to the amblyopic eye only but also affects the fellow eye and that FEM abnormalities can serve as biomarkers to predict the impact of amblyopia on visual functions. Beyond diagnosis, we will discuss the treatment and prognostic implications of the evaluation of FEM abnormalities in clinical practice.
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Affiliation(s)
- Fatema Ghasia
- Cleveland Clinic, Cleveland, OH, United States of America.
| | - Jingyun Wang
- SUNY College of Optometry, NY, New York, United States of America
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Shah S, Shah M, Purohit A, Khanguda V. Perceptual learning with hand - eye coordination as an effective tool for managing amblyopia: A prospective study. Indian J Ophthalmol 2022; 70:3630-3633. [PMID: 36190061 PMCID: PMC9789846 DOI: 10.4103/ijo.ijo_852_22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Purpose Amblyopia is a serious condition resulting in monocular impairment of vision. Although traditional treatment improves vision, we attempted to explore the results of perceptual learning in this study. Methods This prospective cohort study included all patients with amblyopia who were subjected to perceptual learning. The presenting data on vision, stereopsis and contrast sensitivity were documented in a pretested online format, and the pre- and post-treatment information was compared using descriptive, cross-tabulation and comparative methods on SPSS 2.2. The mean values were obtained, and P < 0.05 was considered statistically significant. Results The cohort consisted of 47 patients (23 females and 24 males) with a mean age of 14.11 ± 7.13 years. A statistically significant improvement was detected in visual acuity after the perceptual learning session, and the median follow-up period was 17 days. Also, significant improvements were observed in stereopsis but not in the visual outcomes among the age groups. Conclusion Perceptual learning with hand-eye coordination is an effective method for managing amblyopia. This approach can improve vision in all age groups. However, visual improvement is significantly influenced by ocular alignment.
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Affiliation(s)
| | - Mehul Shah
- Drashti Netralaya, Dahod, Gujarat, India,Correspondence to: Dr. Mehul Shah, Drashti Netralaya, Chakalia Road, Dahod, Gujarat, India. E-mail:
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13
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Hou C, Nicholas SC. Perceptual learning with dichoptic attention tasks improves attentional modulation in V1 and IPS and reduces interocular suppression in human amblyopia. Sci Rep 2022; 12:9660. [PMID: 35690626 PMCID: PMC9188564 DOI: 10.1038/s41598-022-13747-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 05/27/2022] [Indexed: 11/09/2022] Open
Abstract
Long-term and chronic visual suppression to the non-preferred eye in early childhood is a key factor in developing amblyopia, as well as a critical barrier to treat amblyopia. To explore the relationship between selective visual attention and amblyopic suppression and its role in the success of amblyopic training, we used EEG source-imaging to show that training human adults with strabismic and anisometropic amblyopia with dichoptic attention tasks improved attentional modulation of neural populations in the primary visual cortex (V1) and intraparietal sulcus (IPS). We also used psychophysics to show that training reduced interocular suppression along with visual acuity and stereoacuity improvements. Importantly, our results revealed that the reduction of interocular suppression by training was significantly correlated with the improvement of selective visual attention in both training-related and -unrelated tasks in the amblyopic eye, relative to the fellow eye. These findings suggest a relation between interocular suppression and selective visual attention bias between eyes in amblyopic vision, and that dichoptic training with high-attention demand tasks in the amblyopic eye might be an effective way to treat amblyopia.
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Affiliation(s)
- Chuan Hou
- The Smith-Kettlewell Eye Research Institute, San Francisco, CA, 94115, USA.
| | - Spero C Nicholas
- The Smith-Kettlewell Eye Research Institute, San Francisco, CA, 94115, USA
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14
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Huang X, Xia H, Zhang Q, Blakemore C, Nan Y, Wang W, Gao J, Ng SS, Wen J, Huang T, Li X, Pu M. New treatment for amblyopia based on rules of synaptic plasticity: a randomized clinical trial. SCIENCE CHINA. LIFE SCIENCES 2022; 65:451-465. [PMID: 35015247 DOI: 10.1007/s11427-021-2030-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 11/11/2021] [Indexed: 11/29/2022]
Abstract
Amblyopia resulting from early deprivation of vision or defocus in one eye reflects an imbalance of input from the eyes to the visual cortex. We tested the hypothesis that asynchronous stimulation of the two eyes might induce synaptic plasticity and rebalance input. Experiments on normal adults showed that repetitive brief exposure of grating stimuli, with the onset of each stimulus delayed by 8.3 ms in one eye, results in a shift in perceptual eye dominance. Clinical studies (Clinical trial registration number: ChiCTR2100049130), using popular 3D movies with similar asynchrony between the two eyes (amblyopic eye stimulated first) to treat anisometropic amblyopia, established that just 10.5 h of conditioning over <3 weeks produced improvement that met criteria for successful treatment. The benefits of asynchronous conditioning accumulate over 20-30 45 min sessions, and are maintained for at least 2 years. Finally, we demonstrate that asynchronous binocular treatment alone is more effective than patching only. This novel treatment is popular with children and is some 50 times more efficient than patching alone.
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Affiliation(s)
- Xin Huang
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing, 100083, China.,Key Laboratory on Machine Perception (Ministry of Education), Peking University, Beijing, 100083, China
| | - Huika Xia
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing, 100083, China.,Key Laboratory on Machine Perception (Ministry of Education), Peking University, Beijing, 100083, China.,Department of Ophthalmology, Hebei General Hospital, Shijiazhuang, 050051, China
| | - Qi Zhang
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing, 100083, China.,Key Laboratory on Machine Perception (Ministry of Education), Peking University, Beijing, 100083, China
| | - Colin Blakemore
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China.
| | - Yan Nan
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing, 100083, China.,Key Laboratory on Machine Perception (Ministry of Education), Peking University, Beijing, 100083, China
| | - Wenyao Wang
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing, 100083, China.,Key Laboratory on Machine Perception (Ministry of Education), Peking University, Beijing, 100083, China.,Department of Computer Science, School of Electrical Engineering and Computer Sciences, Peking University, Beijing, 100191, China
| | - Jie Gao
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing, 100083, China.,Key Laboratory on Machine Perception (Ministry of Education), Peking University, Beijing, 100083, China
| | - Spencer S Ng
- Department of Biology, University of California, Los Angeles, 90095-7246, USA
| | - Jing Wen
- Department of Pediatric Ophthalmology, Peking University First Hospital, Beijing, 100034, China.,National Amblyopia and Strabismus Prevention and Treatment Center, Beijing, 100034, China
| | - Tiejun Huang
- Department of Computer Science, School of Electrical Engineering and Computer Sciences, Peking University, Beijing, 100191, China. .,National Engineering Laboratory for Video Technology, Peking University, Beijing, 100871, China.
| | - Xiaoqing Li
- Department of Pediatric Ophthalmology, Peking University First Hospital, Beijing, 100034, China. .,National Amblyopia and Strabismus Prevention and Treatment Center, Beijing, 100034, China.
| | - Mingliang Pu
- Department of Anatomy, School of Basic Medical Sciences, Peking University, Beijing, 100083, China. .,Key Laboratory on Machine Perception (Ministry of Education), Peking University, Beijing, 100083, China.
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15
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Murray J, Gupta P, Dulaney C, Garg K, Shaikh AG, Ghasia FF. Effect of Viewing Conditions on Fixation Eye Movements and Eye Alignment in Amblyopia. Invest Ophthalmol Vis Sci 2022; 63:33. [PMID: 35212720 PMCID: PMC8883146 DOI: 10.1167/iovs.63.2.33] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 02/01/2022] [Indexed: 11/24/2022] Open
Abstract
Purpose Patients with amblyopia are known to have fixation instability, which arises from alteration of physiologic fixation eye movements (FEMs) and nystagmus. We assessed the effects of monocular, binocular, and dichoptic viewing on FEMs and eye alignment in patients with and without fusion maldevelopment nystagmus (FMN). Methods Thirty-four patients with amblyopia and seven healthy controls were recruited for this study. Eye movements were recorded using infrared video-oculography during (1) fellow eye viewing (FEV), (2) amblyopic eye viewing (AEV), (3) both eye viewing (BEV), and (4) dichoptic viewing (DcV) at varying fellow eye (FE) contrasts. The patients were classified per the clinical type of amblyopia and FEM waveforms into those without nystagmus, those with nystagmus with and without FMN. Fixational saccades and intersaccadic drifts, quick and slow phases of nystagmus, and bivariate contour ellipse area were analyzed in the FE and amblyopic eye (AE). Results We found that FEMs are differentially affected with increased amplitude of quick phases of FMN observed during AEV than BEV and during DcV at lower FE contrasts. Increased fixation instability was seen in anisometropic patients at lower FE contrasts. Incomitance of eye misalignment was seen with the greatest increase during FEV. Strabismic/mixed amblyopia patients without FMN were more likely to demonstrate a fixation switch where the AE attends to the target during DcV than patients with FMN. Conclusions Our findings suggest that FEM abnormalities modulate with different viewing conditions as used in various amblyopia therapies. Increased FEM abnormalities could affect the visual function deficits and may have treatment implications.
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Affiliation(s)
- Jordan Murray
- Visual Neurosciences and Ocular Motility Laboratory, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Palak Gupta
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States
- Daroff-Dell'Osso Ocular Motility Laboratory, Louis Stokes Cleveland VA Medical Center, Cleveland, Ohio, United States
| | - Cody Dulaney
- Visual Neurosciences and Ocular Motility Laboratory, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
| | - Kiran Garg
- Case Western Reserve University, Cleveland, Ohio, United States
| | - Aasef G Shaikh
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, United States
- Daroff-Dell'Osso Ocular Motility Laboratory, Louis Stokes Cleveland VA Medical Center, Cleveland, Ohio, United States
- Department of Neurology, Neurological Institute, University Hospitals, Cleveland, Ohio, United States
| | - Fatema F Ghasia
- Visual Neurosciences and Ocular Motility Laboratory, Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, United States
- Daroff-Dell'Osso Ocular Motility Laboratory, Louis Stokes Cleveland VA Medical Center, Cleveland, Ohio, United States
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16
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Hsieh YC, Liao WL, Tsai YY, Lin HJ. Efficacy of vision therapy for unilateral refractive amblyopia in children aged 7-10 years. BMC Ophthalmol 2022; 22:44. [PMID: 35100972 PMCID: PMC8805323 DOI: 10.1186/s12886-022-02246-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 12/28/2021] [Indexed: 11/24/2022] Open
Abstract
Background There is a critical period for visual development, conventionally considered to be the first 6 years of life. Children aged 7 years and older are significantly less responsive to amblyopia treatment. This study investigated the efficacy of binocular vision therapy in amblyopic children aged 7–10 years. Methods This retrospective study enrolled 36 children with unilateral amblyopia who were divided into a case group (receiving vision therapy, optical correction, and part-time patching of the weaker eye) and a control group (receiving optical correction and part-time patching of the weaker eye). Visual acuity (VA) was measured at baseline, at the 3-month, 6-month, and 9-month visits, and 3 months after cessation of treatment. Results There were 19 subjects in the case group and 17 subjects in the control group. Mean VA in the case group improved from 0.39 ± 0.24 logMAR at baseline to 0.10 ± 0.23 logMAR at the endpoint of treatment (p < 0.001, paired t-test). Mean VA in the control group improved from 0.64 ± 0.30 logMAR at baseline to 0.52 ± 0.27 logMAR at the endpoint of treatment (p = 0.015, paired t-test). The improvement was significantly greater in the case group than in the control group (p = 0.006, two-samples independent t-test). All subjects underwent follow-up examinations within 6 to 12 months. There was no regression of VA in the case group 3 months after cessation of vision therapy. The patients in the case group who received visual therapy were with better VA improvement then patients with only optic correction and patching. Conclusions Vision therapy combined with conventional treatment (optical correction and part-time patching) is more effective than conventional treatment alone in children aged 7–10 years with unilateral refractive amblyopia. The treatment results not only in greater vision gain, but also in shorter duration of treatment.
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Affiliation(s)
- Yi-Ching Hsieh
- Department of Ophthalmology, Eye Center, China Medical University Hospital, No. 2, Yude Road, Taichung, Taiwan
| | - Wen-Ling Liao
- Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan.,Personal Medical Research Center, China Medical University Hospital, Taichung, Taiwan
| | - Yi-Yu Tsai
- Department of Ophthalmology, Eye Center, China Medical University Hospital, No. 2, Yude Road, Taichung, Taiwan.,Department of Ophthalmology, China Medial University, Taichung, Taiwan
| | - Hui-Ju Lin
- Department of Ophthalmology, Eye Center, China Medical University Hospital, No. 2, Yude Road, Taichung, Taiwan. .,School of Chinese Medicine, China Medial University, Taichung, Taiwan.
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17
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Hou C. A novel method for utilizing dichoptic attention tasks in amblyopic training. MethodsX 2022; 9:101829. [PMID: 36081490 PMCID: PMC9445385 DOI: 10.1016/j.mex.2022.101829] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Accepted: 08/16/2022] [Indexed: 11/03/2022] Open
Abstract
There is converging evidence of attention deficits in individuals with amblyopia. It has been reported that selective visual attention is allocated preferentially toward the non-amblyopic fellow eye in strabismic ambloypes. This attention allocation bias between the eyes is found related to visual suppression in amblyopia. In this study, I introduced a novel method, which uses dichoptic attention tasks to train individuals with amblyopia and has been demonstrated alleviating visual suppression and improving visual functions while reducing interocular attention bias in adults with amblyopia. The method consists of the following components:The training tasks include three attention factors (searching, counting and cueing) to implement selective visual attention to the amblyopic eye dichoptically. With a dichoptic approach, the targets are presented to the amblyopic eye while the distractors are simultaneously presented to the fellow eye. The tasks are to search and count the targets that are presented to the cued eye among the distractors. The training stimuli avoid typical contrast sensitivity-based tasks, and the targets are highly visible allowing them to be seen by the amblyopic eye with poor visual acuity.
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18
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Sen S, Singh P, Saxena R. Management of amblyopia in pediatric patients: Current insights. Eye (Lond) 2022; 36:44-56. [PMID: 34234293 PMCID: PMC8727565 DOI: 10.1038/s41433-021-01669-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 06/04/2021] [Accepted: 06/22/2021] [Indexed: 02/06/2023] Open
Abstract
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.
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Affiliation(s)
- Sagnik Sen
- Department of Neuroophthalmology and Strabismus, Dr R.P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Pallavi Singh
- Department of Neuroophthalmology and Strabismus, Dr R.P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Rohit Saxena
- Department of Neuroophthalmology and Strabismus, Dr R.P. Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
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19
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Effect of refractive error type in the amblyopic eyes on factors for treatment success in anisometropic amblyopia. Sci Rep 2021; 11:21927. [PMID: 34753997 PMCID: PMC8578641 DOI: 10.1038/s41598-021-01377-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 09/01/2021] [Indexed: 11/08/2022] Open
Abstract
To investigate the factors for treatment success in anisometropic amblyopia according to the spherical equivalent (SE) type of amblyopic eyes. Medical records of 397 children with anisometropic amblyopia aged 3 to 12 years who presented in a secondary referral eye hospital during 2010 ~ 2016 were retrospectively reviewed. Anisometropia was defined as ≥ 1 diopter (D) difference in SE, or ≥ 1.5 D difference of cylindrical error between the eyes. According to the SE of amblyopic eyes, patients were categorized into hyperopia (SE ≥ 1D), emmetropia (− 1 < SE < + 1) and myopia (SE ≤ − 1D) groups. Treatment success was defined as achieving interocular logMAR visual acuity difference < 0.2. Multivariate logistic regression was used to analyze the factors for treatment success. Significant factors for the amblyopia treatment success in hyperopia group (n = 270) were younger age [adjusted odds ratio (aOR) (95% confidence interval, CI) = 0.529 (0.353, 0.792)], better BCVA in amblyopic eyes at presentation [aOR (95% CI) 0.004 (0, 0.096)], longer follow-up period [aOR (95%CI) = 1.098 (1.036, 1.162)], and no previous amblyopia treatment history [aOR (95% CI) 0.059 (0.010, 0.364)]. In myopia group (n = 68), younger age [aOR (95% CI) 0.440 (0.208, 0.928)] and better BCVA in amblyopic eyes [aOR (95% CI) 0.034 (0.003, 0.469)] were associated with higher odds of treatment success. There was no significant factor for treatment success in emmetropia group (n = 59) in this population. The refractive error type of amblyopic eyes at presentation affects the factors for treatment success in anisometropic amblyopia.
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20
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Fong MF, Duffy KR, Leet MP, Candler CT, Bear MF. Correction of amblyopia in cats and mice after the critical period. eLife 2021; 10:e70023. [PMID: 34464258 PMCID: PMC8456712 DOI: 10.7554/elife.70023] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 08/20/2021] [Indexed: 11/25/2022] Open
Abstract
Monocular deprivation early in development causes amblyopia, a severe visual impairment. Prognosis is poor if therapy is initiated after an early critical period. However, clinical observations have shown that recovery from amblyopia can occur later in life when the non-deprived (fellow) eye is removed. The traditional interpretation of this finding is that vision is improved simply by the elimination of interocular suppression in primary visual cortex, revealing responses to previously subthreshold input. However, an alternative explanation is that silencing activity in the fellow eye establishes conditions in visual cortex that enable the weak connections from the amblyopic eye to gain strength, in which case the recovery would persist even if vision is restored in the fellow eye. Consistent with this idea, we show here in cats and mice that temporary inactivation of the fellow eye is sufficient to promote a full and enduring recovery from amblyopia at ages when conventional treatments fail. Thus, connections serving the amblyopic eye are capable of substantial plasticity beyond the critical period, and this potential is unleashed by reversibly silencing the fellow eye.
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Affiliation(s)
- Ming-fai Fong
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Kevin R Duffy
- Department of Psychology and Neuroscience, Dalhousie UniversityHalifaxCanada
| | - Madison P Leet
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Christian T Candler
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
| | - Mark F Bear
- The Picower Institute for Learning and Memory, Department of Brain and Cognitive Sciences, Massachusetts Institute of TechnologyCambridgeUnited States
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21
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Yuan Y, Zhu C, Wang P, Hu X, Yao W, Huang X, Ke B. Alternative Flicker Glass: a New Anti-suppression Approach to the Treatment of Anisometropic Amblyopia. Ophthalmic Res 2021; 64:967-973. [PMID: 33652438 DOI: 10.1159/000515599] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 02/20/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Amlyopia always presents with monocular and binocular dysfunction. In this study, we aim to investage the efficacy of alternative occlusion using liquid crystal glasses versus continuous occlusion therapy using traditional patches for treating amblyopia. METHODS Eligible subjects with anisometropic amblyopia were randomized into two groups: alternative flicker glass (AFG) or patching group. In the AFG group, subjects were instructed to wear the flicker glasses for 1 hour a day. The AFG is a lightweight spectacle frame with liquid crystal lenses that provide direct square-wave alternating occlusion, which were pre-programmed at temporal frequency of 7Hz. In the patching group, the patients were prescribed to wear traditional patches for 2 hours a day. The best corrected visual acuity (BCVA), contrast sensitivity function (CSF) and stereoacuity were measured at the baseline, 3 and 12 weeks. RESULTS In this pilot study, a total of forty children were recruited, with twenty in the AFG group. Mean BCVA improved by 0.17±0.14logMAR (95% CI=0.10 to 0.23) in the AFG group, while 0.18±0.18logMAR (95% CI=0.09 to 0.26) in the patching group from baseline to 12 weeks. The improvement of BCVA in both groups were significant (both P<0.01), while no significant difference between the groups (P=0.82). The CSF of both low and high spatial frequencies exhibited significant improvement at 12 weeks in the AFG group (P<0.01, respectively), while just have a significant improvement at low spatial frequency in the patching group (P<0.01). The stereoacuity significantly improved by 504.00±848.00 (95% CI= -900.88 to -107.12) arc seconds in the AFG group (P<0.05), while 263.50± 639.55 (95% CI=-562.82 to 35.82) arc seconds in the patching group (P>0.05). CONCLUSION Alternative flicker glass was effective in improving both monocular and binocular function, which was most likely achieved by reducing the suppression and promoting binocular fusion. This therapy exhibited promise as an alternative method for amblyopia treatment.
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Affiliation(s)
- Ying Yuan
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- National Clinical Research Center for Eye Diseases, Shanghai, China
| | - Chengcheng Zhu
- Shanghai Key Laboratory of Fundus Disease, Shanghai, China
- Shanghai Engineering Center for Visual Science and Photomedicine, Shanghai, China
| | - Peng Wang
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Shanghai Engineering Center for Precise Diagnosis and Treatment of Eye Diseases, Shanghai, China
| | - Xiaojun Hu
- National Clinical Research Center for Eye Diseases, Shanghai, China
| | - Wenbo Yao
- Shanghai Eye Disease Prevention and Treatment Center, Shanghai, China
| | - Xinhui Huang
- Shanghai Eye Disease Prevention and Treatment Center, Shanghai, China
| | - Bilian Ke
- Department of Ophthalmology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China,
- National Clinical Research Center for Eye Diseases, Shanghai, China,
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22
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Kadhum A, Simonsz‐Tóth B, Rosmalen J, Pijnenburg SJM, Janszen BM, Simonsz HJ, Loudon SE. Long-term follow-up of an amblyopia treatment study: change in visual acuity 15 years after occlusion therapy. Acta Ophthalmol 2021; 99:e36-e42. [PMID: 32657530 PMCID: PMC7891344 DOI: 10.1111/aos.14499] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 05/14/2020] [Indexed: 12/03/2022]
Abstract
Purpose To determine change in visual acuity (VA) in the population of a previous amblyopia treatment study (Loudon 2006) and assess risk factors for VA decrease. Methods Subjects treated between 2001 and 2003 were contacted between December 2015 and July 2017. Orthoptic examination was conducted under controlled circumstances and included subjective refraction, best corrected VA, reading acuity, binocular vision, retinal fixation, cover‐uncover and alternating cover test. As a measure for degree of amblyopia, InterOcular VA Difference (IOD) at the end of occlusion therapy was compared with IOD at the follow‐up examination using Wilcoxon’s signed‐rank test. Regression analysis was conducted to determine the influence of clinical and socio‐economic factors on changes in IOD. Results Out of 303 subjects from the original study, 208 were contacted successfully, 59 refused and 15 were excluded because of non‐amblyopic cause of visual impairment. Mean IOD at end of therapy (mean age 6.4 years) was 0.11 ± 0.16 logMAR, and IOD at follow‐up examination (mean age 18.3 years) was 0.09 ± 0.21 logMAR; this difference was not significant (p = 0.054). Degree of anisometropia (p = 0.008; univariable analysis), increasing anisometropia (p = 0.009; multivariable), eccentric fixation (p < 0.001; univariable and multivariable); large IOD (p < 0.001; univariable and multivariable) and non‐compliance during therapy (p = 0.028; univariable) were associated with IOD increase. Conclusion Long‐term results of occlusion therapy were good. High or increasing anisometropia, eccentric fixation and non‐compliance during occlusion therapy were associated with long‐term VA decrease. Subjects with poor initial VA had a larger increase despite little patching, but often showed long‐term VA decrease.
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Affiliation(s)
- Aveen Kadhum
- Department of Ophthalmology Erasmus University Medical Center Rotterdam The Netherlands
| | - Brigitte Simonsz‐Tóth
- Department of Ophthalmology Haaglanden Medical Center Westeinde Hospital The Hague The Netherlands
| | - Joost Rosmalen
- Department of Biostatistics Erasmus University Medical Center Rotterdam The Netherlands
| | - Sanne J. M. Pijnenburg
- Department of Optometry and Orthoptics University of Applied Sciences Utrecht The Netherlands
| | - Bronte M. Janszen
- Department of Optometry and Orthoptics University of Applied Sciences Utrecht The Netherlands
| | - Huibert J. Simonsz
- Department of Ophthalmology Erasmus University Medical Center Rotterdam The Netherlands
| | - Sjoukje E. Loudon
- Department of Ophthalmology Erasmus University Medical Center Rotterdam The Netherlands
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23
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Scaramuzzi M, Murray J, Nucci P, Shaikh AG, Ghasia FF. Fixational eye movements abnormalities and rate of visual acuity and stereoacuity improvement with part time patching. Sci Rep 2021; 11:1217. [PMID: 33441575 PMCID: PMC7806581 DOI: 10.1038/s41598-020-79077-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 12/03/2020] [Indexed: 11/09/2022] Open
Abstract
Residual amblyopia is seen in 40% of amblyopic patients treated with part-time patching. Amblyopic patients with infantile onset strabismus or anisometropia can develop fusion maldevelopment nystagmus syndrome (FMNS). The purpose of this study was to understand the effects of presence of FMNS and clinical subtype of amblyopia on visual acuity and stereo-acuity improvement in children treated with part-time patching. Forty amblyopic children who had fixation eye movement recordings and at least 12 months of follow-up after initiating part-time patching were included. We classified amblyopic subjects per the fixational eye movements characteristics into those without any nystagmus, those with FMNS and patients with nystagmus without any structural anomalies that do not meet the criteria of FMNS or idiopathic infantile nystagmus. We also classified the patients per the clinical type of amblyopia. Patching was continued until amblyopia was resolved or no visual acuity improvement was noted at two consecutive visits. Children with anisometropic amblyopia and without FMNS have a faster improvement and plateaued sooner. Regression was only seen in patients with strabismic/mixed amblyopia particularly those with FMNS. Patients with FMNS had improvement in visual acuity but poor stereopsis with part-time patching and required longer duration of treatment.
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Affiliation(s)
- Matteo Scaramuzzi
- Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
- Department of Neuroscience, Unit of Ophthalmology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
- DISCCO, University of Milan, Milan, Italy
| | - Jordan Murray
- Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
| | | | - Aasef G Shaikh
- Daroff-Dell'Osso Ocular Motility Laboratory, Cleveland, OH, USA
- Case Medical Center, Case Western Reserve University, Cleveland, OH, USA
| | - Fatema F Ghasia
- Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA.
- Case Medical Center, Case Western Reserve University, Cleveland, OH, USA.
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Amblyopia Outcomes Through Clinical Trials and Practice Measurement: Room for Improvement: The LXXVII Edward Jackson Memorial Lecture. Am J Ophthalmol 2020; 219:A1-A26. [PMID: 32777377 DOI: 10.1016/j.ajo.2020.07.053] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 07/27/2020] [Indexed: 11/21/2022]
Abstract
PURPOSE To describe amblyopia prevalence and outcomes using results from randomized studies and a clinical registry. DESIGN Review of published studies, analysis of data in Intelligent Research in Sight (IRIS) Registry from 2013 to 2019, personal perspective. METHODS Literature review, analysis of IRIS Registry data and IRIS-50, a visual acuity quality measure. RESULTS Clinical trials have reduced the treatment burden of amblyopia by reducing hours of patching and frequency of atropine eye drops with clinical success of about 83%. There is no appreciable age effect if treatment is started before 5 years of age, outcomes are stable to at least 15 years of age, and treatment can be somewhat effective until 12 years of age. The IRIS Registry identified 1,760,066 individuals with amblyopia for a prevalence of 2.47%. Refractive error alone accounted for 68.9% of childhood cases. Mean amblyopic eye visual acuity improved 1.8 lines for children 3-6 years of age and 0.8 lines for 7-12 years, but mean residual amblyopia was more than 2 lines. Among 18,841 children aged 3-7 years eligible for IRIS-50, 77.3% were successful. The odds ratios for success were significantly lower for African-American (0.67; 95% confidence interval [CI] = 0.58 to 0.78) and Hispanic or Latino (0.84; 95% CI = 0.75 to 0.94) children compared with white children. CONCLUSIONS Clinical trials provided evidence of a beneficial effect from several treatments, with substantially reduced doses than previously recommended. Registry data from clinical practice found residual visual acuity impairment among all ages and races, especially among minorities.
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Elfadaly D, Abdelrazik ST, Thomas PBM, Dekker TM, Dahlmann-Noor A, Jones PR. Can Psychophysics Be Fun? Exploring the Feasibility of a Gamified Contrast Sensitivity Function Measure in Amblyopic Children Aged 4-9 Years. Front Med (Lausanne) 2020; 7:469. [PMID: 32984366 PMCID: PMC7480072 DOI: 10.3389/fmed.2020.00469] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 07/13/2020] [Indexed: 12/04/2022] Open
Abstract
Routine assessments of the Contrast Sensitivity Function [CSF] could be useful for the diagnosis and monitoring of amblyopia. However, current CSF measures are not clinically practical, as they are too slow, too boring, and too uncomfortable to sustain a young child's interest. Here we assess the feasibility of a more gamified approach to CSF testing, in which a maximum likelihood psychophysical algorithm (QUEST+) is combined with a largely unconstrained user interface (no fixation target, head restraints, or discrete trials). Twenty-five amblyopes (strabismic, anisometropic, or mixed) aged 4.0–9.2 years performed the gamified CSF assessment monocularly (once per eye). The test required the child to “pop” (press) grating stimuli as they “bounced” around a tablet screen. Head tracking via the tablet's front-facing camera was used to adjust for variations in viewing distance post hoc. CSFs were fitted for each eye, and Area Under the CSF (AUCSF) computed as a summary measure of sensitivity. The results showed that AUCSF measurements were able to separate moderately and severely amblyopic eyes from fellow eyes (case-control effect), and to distinguish individuals with varying degrees of vision loss (dose effect). Even the youngest children exhibited no difficulties completing the test or comprehending what to do, and most children appeared to find the test genuinely enjoyable. Informal feedback from a focus group of older children was also positive, although potential shortcomings with the present design were identified. This feasibility study indicates that gamified, child-friendly vision assessments have promise as a future means of pediatric clinical assessment. Such measures could be particularly valuable for assessing children outside of conventional eye-care facilities (e.g., home-monitoring, school screening).
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Affiliation(s)
- Doaa Elfadaly
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.,Department of Ophthalmology, Faculty of Medicine, Minia University, Minia, Egypt
| | | | - Peter B M Thomas
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.,NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom
| | - Tessa M Dekker
- Child Vision Laboratory, Institute of Ophthalmology, University College London (UCL), London, United Kingdom
| | - Annegret Dahlmann-Noor
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.,NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom
| | - Pete R Jones
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom.,Child Vision Laboratory, Institute of Ophthalmology, University College London (UCL), London, United Kingdom.,Division of Optometry and Visual Sciences, City, University of London, London, United Kingdom
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Lee YH, Maniglia M, Velez F, Demer JL, Seitz AR, Pineles S. Short-term Perceptual Learning Game Does Not Improve Patching-Resistant Amblyopia in Older Children. J Pediatr Ophthalmol Strabismus 2020; 57:176-184. [PMID: 32453851 DOI: 10.3928/01913913-20200306-01] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 02/19/2020] [Indexed: 11/20/2022]
Abstract
PURPOSE To investigate self-administered, at-home use of a perceptual learning-based video game consisting of target detection of stimuli in different sizes, spatial frequency, orientation, and contrast as a potential dichoptic therapy to improve binocular function in amblyopic patients resistant to patching. METHODS Children (ages 8 to 18 years) with strabismic and/or anisometropic amblyopia were recruited from a single institution. All participants (n = 25) were prescribed 6 weeks of patching for 2 hours per day, and those whose visual acuity did not improve were randomized to binocular perceptual learning (n = 7), monocular perceptual learning (n = 8), or patching (n = 10) groups for 8 weeks in this prospective cohort study. After an 8-week long period of treatment cessation, during which participants stopped patching or perceptual learning, participants in the patching group were randomized to binocular or monocular perceptual learning training; those in the perceptual learning groups remained the same. Visual function was assessed by visual acuity, low contrast acuity, reading speed, stereoacuity, and binocularity; compliance was evaluated by exercise logs. RESULTS There were no significant improvements in visual function parameters, which did not vary by treatment group. However, some visual outcomes, such as binocular summation and reading speed, correlated positively with compliance to perceptual learning therapy. CONCLUSIONS At-home, self-administered use of this perceptual learning-based video game-based visual training does not consistently add therapeutic benefit to those with amblyopia resistant to patching. Future investigation is required to determine whether methods to increase compliance will lead to more reliable outcomes. [J Pediatr Ophthalmol Strabismus. 2020;57(3):176-184.].
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Shi W, He L, Lv B, Li L, Wu T. Evaluating the Acute Effect of Stereoscopic Recovery by Dichoptic Stimulation Using Electroencephalogram. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2020; 2020:9497369. [PMID: 32351615 PMCID: PMC7174909 DOI: 10.1155/2020/9497369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 03/19/2020] [Accepted: 03/23/2020] [Indexed: 11/17/2022]
Abstract
Amblyopia is a common developmental disorder in adolescents and children. Stereoscopic loss is a symptom of amblyopia that can seriously affect the quality of patient's life. Recent studies have shown that the push-pull perceptual learning protocol had a positive effect on stereoscopic recovery. In this study, we developed a stereoscopic training method using a polarized visualization system according to the push-pull protocol. Dichoptic stimulation for 36 anisometropic and amblyopic subjects and 33 children with normal visual acuity (VA) has been conducted. Electroencephalogram (EEG) was used to evaluate the neurophysiological changes before, during, and after stimulation. For the anisometropic and amblyopic subjects, the statistical analysis demonstrated significant differences (p < 0.01) in the beta rhythm at the middle temporal and occipital lobes, while the EEG from the normal VA subjects indicated no significant changes when comparing the results before and after training. We concluded that the dichoptic training in our study can activate the middle temporal visual area and visual cortex. The EEG changes can be used to evaluate the training effects. This study also found that the beta band EEG acquired during visual stimulation at the dorsal visual stream can be potentially used for predicting acute training effect. The results facilitated the optimization of the individual training plan.
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Affiliation(s)
- Wei Shi
- Department of Ophthalmology, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Luyang He
- China Academy of Information and Communications Technology, Beijing, China
| | - Bin Lv
- China Academy of Information and Communications Technology, Beijing, China
| | - Li Li
- Department of Ophthalmology, Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Tongning Wu
- China Academy of Information and Communications Technology, Beijing, China
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Chen Y, He Z, Mao Y, Chen H, Zhou J, Hess RF. Patching and Suppression in Amblyopia: One Mechanism or Two? Front Neurosci 2020; 13:1364. [PMID: 32009874 PMCID: PMC6974542 DOI: 10.3389/fnins.2019.01364] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 12/03/2019] [Indexed: 01/26/2023] Open
Abstract
Purpose To determine if benefits from occlusion therapy are due to decreased suppression from the fellow eye in children with amblyopia. Methods Ten newly diagnosed amblyopes (7.2 ± 1.4 years old), two with strabismus and eight with anisometropia, participated. Patients were first given a 2-month period of refractive adaptation, followed by occlusion therapy (i.e., patching their fellow eye with an opaque patch for 4 h/day). Visual acuity of the amblyopic eye and interocular suppression were measured before and after 0.5, 1, 2, 4, and 6 months of occlusion therapy. We quantified interocular suppression with a binocular phase combination task. Results Visual acuity (in logMAR) improved from 0.50 ± 0.22 (mean ± SD) to 0.33 ± 0.20 for patients who finished a short-term (2 months) occlusion (A1–A10), from 0.53 ± 0.20 to 0.32 ± 0.22 for patients who finished a medium-term (4 months) occlusion (A1–A9), and from 0.48 ± 0.19 to 0.22 ± 0.10 for patients who finished a long-term (6 months) occlusion (A1–A8). Although their visual acuity significantly improved, their degree of suppression, which was abnormal in all cases, did not change consistently. This was true in all durations of occlusion therapy. Conclusion Reduced suppression from the fixing eye might not be result from occlusion therapy.
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Affiliation(s)
- Yiya Chen
- School of Ophthalmology and Optometry and Eye Hospital, State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China
| | - Zhifen He
- School of Ophthalmology and Optometry and Eye Hospital, State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China
| | - Yu Mao
- School of Ophthalmology and Optometry and Eye Hospital, State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China
| | - Hao Chen
- School of Ophthalmology and Optometry and Eye Hospital, State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China
| | - Jiawei Zhou
- School of Ophthalmology and Optometry and Eye Hospital, State Key Laboratory of Ophthalmology, Optometry and Vision Science, Wenzhou Medical University, Wenzhou, China
| | - Robert F Hess
- McGill Vision Research, Department of Ophthalmology and Visual Sciences, McGill University, Montreal, QC, Canada
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Gopal SKS, Kelkar J, Kelkar A, Pandit A. Simplified updates on the pathophysiology and recent developments in the treatment of amblyopia: A review. Indian J Ophthalmol 2020; 67:1392-1399. [PMID: 31436180 PMCID: PMC6727694 DOI: 10.4103/ijo.ijo_11_19] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Amblyopia is the most common cause of monocular visual impairment affecting 2-5% of the general population. Amblyopia is a developmental cortical disorder of the visual pathway essentially due to abnormal visual stimulus, reaching the binocular cortical cells, which may be multivariate. Ganglion cells are of two types: parvocellular (P cells) and magnocellular (M cells); they are the first step where the light energy is converted in to neural impulse. P cells are involved in fine visual acuity, fine stereopsis, and color vision and M cells are involved in gross stereopsis and movement recognition. Strabismus, refractive error, cataract, and ptosis, occurring during critical period are highly amblyogenic. The critical period extends from birth to 7--8 years. The earlier the clinically significant refractive error and strabismus are detected and treated, the greater the likelihood of preventing amblyopia. Treatment for amblyopia in children includes: optical correction of significant refractive errors, patching, pharmacological treatment, and alternative therapies which include: vision therapy, binocular therapy, and liquid crystal display eyeglasses are newer treatment modalities for amblyopia. Age of starting the treatment is not predictive of outcome, instituting treatment on detection and early detection plays a role in achieving better outcomes. This review aims to give a simplified update on amblyopia, which will be of use to a clinician, in understanding the pathophysiology of the complex condition. We also share the cortical aspects of amblyopia and give recent developments in the treatment of amblyopia.
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Affiliation(s)
- Santhan K S Gopal
- Kamala Nethralaya Eye Clinic and Surgical Centre, Bengaluru, Karnataka, India
| | - Jai Kelkar
- National Institute of Ophthalmology, Maharashtra, India
| | - Aditya Kelkar
- National Institute of Ophthalmology, Maharashtra, India
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Lim HR, Kim DH. Risk Factors Associated with the Recurrence of Amblyopia after Successful Treatment. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2020. [DOI: 10.3341/jkos.2020.61.1.86] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Hwa Rang Lim
- Department of Ophthalmology, Chosun University College of Medicine, Gwangju, Korea
| | - Dae Hyun Kim
- Department of Ophthalmology, Chosun University College of Medicine, Gwangju, Korea
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Zhou J, He Z, Wu Y, Chen Y, Chen X, Liang Y, Mao Y, Yao Z, Lu F, Qu J, Hess RF. Inverse Occlusion: A Binocularly Motivated Treatment for Amblyopia. Neural Plast 2019; 2019:5157628. [PMID: 31015829 PMCID: PMC6444262 DOI: 10.1155/2019/5157628] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 11/23/2018] [Accepted: 01/08/2019] [Indexed: 11/18/2022] Open
Abstract
Recent laboratory findings suggest that short-term patching of the amblyopic eye (i.e., inverse occlusion) results in a larger and more sustained improvement in the binocular balance compared with normal controls. In this study, we investigate the cumulative effects of the short-term inverse occlusion in adults and old children with amblyopia. This is a prospective cohort study of 18 amblyopes (10-35 years old; 2 with strabismus) who have been subjected to 2 hours/day of inverse occlusion for 2 months. Patients who required refractive correction or whose refractive correction needed updating were given a 2-month period of refractive adaptation. The primary outcome measure was the binocular balance which was measured using a phase combination task; the secondary outcome measures were the best-corrected visual acuity which was measured with a Tumbling E acuity chart and converted to logMAR units and the stereoacuity which was measured with the Random-dot preschool stereogram test. The average binocular gain was 0.11 in terms of the effective contrast ratio (z = -2.344, p = 0.019, 2-tailed related samples Wilcoxon Signed Rank Test). The average acuity gain was 0.13 logMAR equivalent (t(17) = 4.76, p < 0.001, 2-tailed paired samples t-test). The average stereoacuity gain was 339 arc seconds (z = -2.533, p = 0.011). Based on more recent research concerning adult ocular dominance plasticity, we conclude that inverse occlusion in adults and old children with amblyopia does produce long-term gains to binocular balance and that acuity and stereopsis can improve in some subjects.
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Affiliation(s)
- Jiawei Zhou
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Zhifen He
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Yidong Wu
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Yiya Chen
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Xiaoxin Chen
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Yunjie Liang
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Yu Mao
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Zhimo Yao
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Fan Lu
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Jia Qu
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325003, China
| | - Robert F. Hess
- McGill University, McGill Vision Research, Department of Ophthalmology, Quebec, Montreal, Canada H3G 1A4
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The treatment of amblyopia: current practice and emerging trends. Graefes Arch Clin Exp Ophthalmol 2019; 257:1061-1078. [DOI: 10.1007/s00417-019-04254-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 12/22/2018] [Accepted: 01/17/2019] [Indexed: 02/04/2023] Open
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Refractive adaptation and efficacy of occlusion therapy in untreated amblyopic patients aged 12 to 40 years. Graefes Arch Clin Exp Ophthalmol 2018; 257:379-389. [DOI: 10.1007/s00417-018-4170-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 09/11/2018] [Accepted: 10/16/2018] [Indexed: 10/27/2022] Open
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Bocci T, Nasini F, Caleo M, Restani L, Barloscio D, Ardolino G, Priori A, Maffei L, Nardi M, Sartucci F. Unilateral Application of Cathodal tDCS Reduces Transcallosal Inhibition and Improves Visual Acuity in Amblyopic Patients. Front Behav Neurosci 2018; 12:109. [PMID: 29896093 PMCID: PMC5986963 DOI: 10.3389/fnbeh.2018.00109] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/09/2018] [Indexed: 12/12/2022] Open
Abstract
Objective: Amblyopia is a neurodevelopmental disorder characterized by visual acuity and contrast sensitivity loss, refractory to pharmacological and optical treatments in adulthood. In animals, the corpus callosum (CC) contributes to suppression of visual responses of the amblyopic eye. To investigate the role of interhemispheric pathways in amblyopic patients, we studied the response of the visual cortex to transcranial Direct Current Stimulation (tDCS) applied over the primary visual area (V1) contralateral to the “lazy eye.” Methods: Visual acuity (logMAR) was assessed before (T0), immediately after (T1) and 60’ following the application of cathodal tDCS (2.0 mA, 20’) in 12 amblyopic patients. At each time point, Visual Evoked Potentials (VEPs) triggered by grating stimuli of different contrasts (K90%, K20%) were recorded in both hemispheres and compared to those obtained in healthy volunteers. Results: Cathodal tDCS improved visual acuity respect to baseline (p < 0.0001), whereas sham polarization had no significant effect. At T1, tDCS induced an inhibitory effect on VEPs amplitudes at all contrasts in the targeted side and a facilitation of responses in the hemisphere ipsilateral to the amblyopic eye; compared with controls, the facilitation persisted at T2 for high contrasts (K90%; Holm–Sidak post hoc method, p < 0.001), while the stimulated hemisphere recovered more quickly from inhibition (Holm–Sidak post hoc method, p < 0.001). Conclusions: tDCS is a promising treatment for amblyopia in adults. The rapid recovery of excitability and the concurrent transcallosal disinhibition following perturbation of cortical activity may support a critical role of interhemispheric balance in the pathophysiology of amblyopia.
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Affiliation(s)
- Tommaso Bocci
- Section of Neurophysiopathology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.,Clinical Center for Neurotechnologies, Neuromodulation, and Movement Disorders, Fondazione IRCCS Ca'Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Francesco Nasini
- Department of Surgical, Medical, and Molecular Pathology and Critical Care, University of Pisa, Pisa, Italy
| | - Matteo Caleo
- CNR Institute of Neuroscience, University of Pisa, Pisa, Italy
| | - Laura Restani
- CNR Institute of Neuroscience, University of Pisa, Pisa, Italy
| | - Davide Barloscio
- Section of Neurophysiopathology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Gianluca Ardolino
- Clinical Center for Neurotechnologies, Neuromodulation, and Movement Disorders, Fondazione IRCCS Ca'Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Alberto Priori
- Clinical Center for Neurotechnologies, Neuromodulation, and Movement Disorders, Fondazione IRCCS Ca'Granda Ospedale Maggiore Policlinico, Milan, Italy.,Department of Health Sciences, University of Milan and Ospedale San Paolo, Milan, Italy
| | - Lamberto Maffei
- CNR Institute of Neuroscience, University of Pisa, Pisa, Italy
| | - Marco Nardi
- Department of Surgical, Medical, and Molecular Pathology and Critical Care, University of Pisa, Pisa, Italy
| | - Ferdinando Sartucci
- Section of Neurophysiopathology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.,CNR Institute of Neuroscience, University of Pisa, Pisa, Italy
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Nassar MM, Mitchell FC. The Need for a Unified Protocol for Termination of Amblyopia Treatment. Br Ir Orthopt J 2018; 14:20-24. [PMID: 32999960 PMCID: PMC7510402 DOI: 10.22599/bioj.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Introduction: Many authors have investigated the methodology and outcomes of amblyopia treatment. However, the evidence on termination of treatment, specifically referring to the stability of visual outcome and timing of reviewing patients after treatment ends, has received less interest with no agreement on risk factors of visual regression. Purpose: To study the final part of amblyopia service with particular emphasis to stability of visual outcome; efficacy and timing of follow up after treatment ends. Methods: A retrospective review of patients discharged following treatment for strabismic and anisometropic amblyopia. Exclusion criteria were ocular pathology, poor attendance or poor compliance. Collected data included: age at the start of treatment, type and duration of treatment, number of visits, visual acuity (at start and end). Additionally, we analysed the duration and number of visits after stopping treatment, final visual acuity at discharge and duration of treatment with minimal change in vision. Results: Thirty-nine patients were identified with a mean age 4.2 ± 1.7SD years. Patients had an average of 116.6 ± 13.9SD visits over 30.5 ± 21.5SD months. Of these, 71.8% had occlusion only and 28.2% in combination with atropine. All but three patients had improved vision, with mean letters gained 13.2 ± 8.7SD LogMAR. The improvement in vision was statistically significant p < 0.005 and patients were further followed without treatment for 10 ± 13.5SD months over 5.2 ± 6.6SD visits. The mean final vision at discharge was not significantly different from vision at termination (p = 0.68) and we found no significant recurrence. Conclusion: Amblyopia treatment is effective; however, there is inconsistency in many aspects of ending treatment. Further improvement is needed to standardise care from termination of treatment up to discharge from service.
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Gao TY, Anstice N, Babu RJ, Black JM, Bobier WR, Dai S, Guo CX, Hess RF, Jenkins M, Jiang Y, Kearns L, Kowal L, Lam CSY, Pang PCK, Parag V, South J, Staffieri SE, Wadham A, Walker N, Thompson B. Optical treatment of amblyopia in older children and adults is essential prior to enrolment in a clinical trial. Ophthalmic Physiol Opt 2018; 38:129-143. [PMID: 29356022 DOI: 10.1111/opo.12437] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 12/03/2017] [Indexed: 11/29/2022]
Abstract
PURPOSE Optical treatment alone can improve visual acuity (VA) in children with amblyopia, thus clinical trials investigating additional amblyopia therapies (such as patching or videogames) for children require a preceding optical treatment phase. Emerging therapies for adult patients are entering clinical trials. It is unknown whether optical treatment is effective for adults with amblyopia and whether an optical correction phase is required for trials involving adults. METHODS We examined participants who underwent optical treatment in the Binocular Treatment for Amblyopia using Videogames (BRAVO) clinical trial (ANZCTR ID: ACTRN12613001004752). Participants were recruited in three age groups (7 to 12, 13 to 17, or ≥18 years), and had unilateral amblyopia due to anisometropia and/or strabismus, with amblyopic eye VA of 0.30-1.00 logMAR (6/12 to 6/60, 20/40 to 20/200). Corrective lenses were prescribed based on cycloplegic refraction to fully correct any anisometropia. VA was assessed using the electronic visual acuity testing algorithm (e-ETDRS) test and near stereoacuity was assessed using the Randot Preschool Test. Participants were assessed every four weeks up to 16 weeks, until either VA was stable or until amblyopic eye VA improved to better than 0.30 logMAR, rendering the participant ineligible for the trial. RESULTS Eighty participants (mean age 24.6 years, range 7.6-55.5 years) completed four to 16 weeks of optical treatment. A small but statistically significant mean improvement in amblyopic eye VA of 0.05 logMAR was observed (S.D. 0.08 logMAR; paired t-test p < 0.0001). Twenty-five participants (31%) improved by ≥1 logMAR line and of these, seven (9%) improved by ≥2 logMAR lines. Stereoacuity improved in 15 participants (19%). Visual improvements were not associated with age, presence of strabismus, or prior occlusion treatment. Two adult participants withdrew due to intolerance to anisometropic correction. Sixteen out of 80 participants (20%) achieved better than 0.30 logMAR VA in the amblyopic eye after optical treatment. Nine of these participants attended additional follow-up and four (44%) showed further VA improvements. CONCLUSIONS Improvements from optical treatment resulted in one-fifth of participants becoming ineligible for the main clinical trial. Studies investigating additional amblyopia therapies must include an appropriate optical treatment only phase and/or parallel treatment group regardless of patient age. Optical treatment of amblyopia in adult patients warrants further investigation.
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Affiliation(s)
- Tina Y Gao
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Nicola Anstice
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Raiju J Babu
- School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada
| | - Joanna M Black
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - William R Bobier
- School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada
| | - Shuan Dai
- Department of Ophthalmology, Auckland City Hospital and Starship Children's Hospital, Auckland, New Zealand
| | - Cindy X Guo
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Robert F Hess
- Department of Ophthalmology, McGill Vision Research, McGill University, Montreal, Quebec, Canada
| | - Michelle Jenkins
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Yannan Jiang
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Lisa Kearns
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Lionel Kowal
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Carly S Y Lam
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Peter C K Pang
- School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Varsha Parag
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Jayshree South
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Sandra Elfride Staffieri
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Victoria, Australia.,Ophthalmology, Department of Surgery, University of Melbourne, Melbourne, Victoria, Australia
| | - Angela Wadham
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Natalie Walker
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Benjamin Thompson
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand.,School of Optometry and Vision Science, University of Waterloo, Waterloo, Ontario, Canada
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Yazdani N, Sadeghi R, Momeni-Moghaddam H, Zarifmahmoudi L, Ehsaei A, Barrett BT. Part-time versus full-time occlusion therapy for treatment of amblyopia: A meta-analysis. J Curr Ophthalmol 2017; 29:76-84. [PMID: 28626815 PMCID: PMC5463007 DOI: 10.1016/j.joco.2017.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 01/09/2017] [Accepted: 01/29/2017] [Indexed: 12/03/2022] Open
Abstract
PURPOSE To compare full-time occlusion (FTO) and part-time occlusion (PTO) therapy in the treatment of amblyopia, with the secondary aim of evaluating the minimum number of hours of part-time patching required for maximal effect from occlusion. METHODS A literature search was performed in PubMed, Scopus, Science Direct, Ovid, Web of Science and Cochrane library. Methodological quality of the literature was evaluated according to the Oxford Center for Evidence Based Medicine and modified Newcastle-Ottawa scale. Statistical analyses were performed using Comprehensive Meta-Analysis (version 2, Biostat Inc., USA). RESULTS The present meta-analysis included six studies [three randomized controlled trials (RCTs) and three non-RCTs]. Pooled standardized difference in the mean changes in the visual acuity was 0.337 [lower and upper limits: -0.009, 0.683] higher in the FTO as compared to the PTO group; however, this difference was not statistically significant (P = 0.056, Cochrane Q value = 20.4 (P = 0.001), I2 = 75.49%). Egger's regression intercept was 5.46 (P = 0.04). The pooled standardized difference in means of visual acuity changes was 1.097 [lower and upper limits: 0.68, 1.513] higher in the FTO arm (P < 0.001), and 0.7 [lower and upper limits: 0.315, 1.085] higher in the PTO arm (P < 0.001) compared to PTO less than two hours. CONCLUSIONS This meta-analysis shows no statistically significant difference between PTO and FTO in treatment of amblyopia. However, our results suggest that the minimum effective PTO duration, to observe maximal improvement in visual acuity is six hours per day.
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Affiliation(s)
- Negareh Yazdani
- Refractive Errors Research Center, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Optometry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Ramin Sadeghi
- Nuclear Medicine Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hamed Momeni-Moghaddam
- Refractive Errors Research Center, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Optometry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Leili Zarifmahmoudi
- Nuclear Medicine Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Asieh Ehsaei
- Refractive Errors Research Center, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
- Department of Optometry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Brendan T. Barrett
- School of Optometry and Vision Science, University of Bradford, Bradford, United Kingdom
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Guo CX, Babu RJ, Black JM, Bobier WR, Lam CSY, Dai S, Gao TY, Hess RF, Jenkins M, Jiang Y, Kowal L, Parag V, South J, Staffieri SE, Walker N, Wadham A, Thompson B. Binocular treatment of amblyopia using videogames (BRAVO): study protocol for a randomised controlled trial. Trials 2016; 17:504. [PMID: 27756405 PMCID: PMC5069878 DOI: 10.1186/s13063-016-1635-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 09/30/2016] [Indexed: 12/02/2022] Open
Abstract
Background Amblyopia is a common neurodevelopmental disorder of vision that is characterised by visual impairment in one eye and compromised binocular visual function. Existing evidence-based treatments for children include patching the nonamblyopic eye to encourage use of the amblyopic eye. Currently there are no widely accepted treatments available for adults with amblyopia. The aim of this trial is to assess the efficacy of a new binocular, videogame-based treatment for amblyopia in older children and adults. We hypothesise that binocular treatment will significantly improve amblyopic eye visual acuity relative to placebo treatment. Methods/design The BRAVO study is a double-blind, randomised, placebo-controlled multicentre trial to assess the effectiveness of a novel videogame-based binocular treatment for amblyopia. One hundred and eight participants aged 7 years or older with anisometropic and/or strabismic amblyopia (defined as ≥0.2 LogMAR interocular visual acuity difference, ≥0.3 LogMAR amblyopic eye visual acuity and no ocular disease) will be recruited via ophthalmologists, optometrists, clinical record searches and public advertisements at five sites in New Zealand, Canada, Hong Kong and Australia. Eligible participants will be randomised by computer in a 1:1 ratio, with stratification by age group: 7–12, 13–17 and 18 years and older. Participants will be randomised to receive 6 weeks of active or placebo home-based binocular treatment. Treatment will be in the form of a modified interactive falling-blocks game, implemented on a 5th generation iPod touch device viewed through red/green anaglyphic glasses. Participants and those assessing outcomes will be blinded to group assignment. The primary outcome is the change in best-corrected distance visual acuity in the amblyopic eye from baseline to 6 weeks post randomisation. Secondary outcomes include distance and near visual acuity, stereopsis, interocular suppression, angle of strabismus (where applicable) measured at baseline, 3, 6, 12 and 24 weeks post randomisation. Treatment compliance and acceptability will also be assessed along with quality of life for adult participants. Discussion The BRAVO study is the first randomised controlled trial of a home-based videogame treatment for older children and adults with amblyopia. The results will indicate whether a binocular approach to amblyopia treatment conducted at home is effective for patients aged 7 years or older. Trial registration This trial was registered in Australia and New Zealand Clinical Trials Registry (ACTRN12613001004752) on 10 September 2013.
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Affiliation(s)
- Cindy X Guo
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Raiju J Babu
- School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Joanna M Black
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - William R Bobier
- School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada
| | - Carly S Y Lam
- School of Optometry, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hong Kong, SAR, China
| | - Shuan Dai
- Department of Ophthalmology, Starship Children's Hospital, Auckland, New Zealand
| | - Tina Y Gao
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Robert F Hess
- Department of Ophthalmology, McGill Vision Research, McGill University, Montreal, QC, Canada
| | - Michelle Jenkins
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Yannan Jiang
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Lionel Kowal
- Department of Surgery, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital; Ophthalmology, University of Melbourne, Melbourne, VIC, Australia
| | - Varsha Parag
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Jayshree South
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand
| | - Sandra Elfride Staffieri
- Department of Surgery, Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital; Ophthalmology, University of Melbourne, Melbourne, VIC, Australia
| | - Natalie Walker
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Angela Wadham
- National Institute for Health Innovation, School of Population Health, The University of Auckland, Auckland, New Zealand
| | - Benjamin Thompson
- School of Optometry and Vision Science, The University of Auckland, Auckland, New Zealand. .,School of Optometry and Vision Science, University of Waterloo, Waterloo, ON, Canada.
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Risk factors for treatment failure and recurrence of anisometropic amblyopia. Int Ophthalmol 2016; 37:835-842. [PMID: 27620472 DOI: 10.1007/s10792-016-0345-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 09/06/2016] [Indexed: 10/21/2022]
Abstract
PURPOSE The aim of this study was to identify factors associated with failed vision improvement and recurrence following occlusion therapy for anisometropic amblyopia in children aged 7-9 years. METHODS We retrospectively reviewed the medical records of 64 children aged 7-9 years who had been diagnosed as having anisometropic amblyopia and were treated with patching. Functional treatment failure was defined as final visual acuity in the amblyopic eye of worse than 20/32. Improvement of fewer than two logMAR lines was considered relative treatment failure. Recurrence was defined as the reduction of at least two logMAR levels of visual acuity after decreased or discontinued patching. RESULTS Functional and relative success rates were 51.6 and 62.5 %, respectively. The most important factor for functional treatment failure [adjusted odds ratio (OR) (95 % confidence interval, CI) 11.57 (1.4-95.74)] and the only risk factor for recurrence [adjusted OR (95 % CI) 3.04 (1.13-8.12)] were the same: high spherical equivalent (SE) of the amblyopic eye. A large interocular difference in the best-corrected visual acuity was found to be a risk factor for both functional and relative failure. CONCLUSION High SE of the amblyopic eye was the most influential risk factor for treatment failure and recurrence in compliant children aged 7-9 years.
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40
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Maconachie GDE, Gottlob I. The challenges of amblyopia treatment. Biomed J 2016; 38:510-6. [PMID: 27013450 PMCID: PMC6138377 DOI: 10.1016/j.bj.2015.06.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 06/08/2015] [Indexed: 11/22/2022] Open
Abstract
The treatment of amblyopia, particularly anisometropic (difference in refractive correction) and/or strabismic (turn of one eye) amblyopia has long been a challenge for many clinicians. Achieving optimum outcomes, where the amblyopic eye reaches a visual acuity similar to the fellow eye, is often impossible in many patients. Part of this challenge has resulted from a previous lack of scientific evidence for amblyopia treatment that was highlight by a systematic review by Snowdon et al. in 1998. Since this review, a number of publications have revealed new findings in the treatment of amblyopia. This includes the finding that less intensive occlusion treatments can be successful in treating amblyopia. A relationship between adherence to treatment and visual acuity has also been established and has been shown to be influenced by the use of intervention material. In addition, there is growing evidence of that a period of glasses wearing only can significantly improve visual acuity alone without any other modes of treatment. This review article reports findings since the Snowdon's report.
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Affiliation(s)
- Gail D E Maconachie
- Ulverscroft Eye Unit, Department of Neuroscience, Psychology and Behaviour, University of Leicester, RKSCB, Leicester Royal Infirmary, Leicester LE2 7LX, UK
| | - Irene Gottlob
- Ulverscroft Eye Unit, Department of Neuroscience, Psychology and Behaviour, University of Leicester, RKSCB, Leicester Royal Infirmary, Leicester LE2 7LX, UK.
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41
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Xiao O, Morgan IG, Ellwein LB, He M. Prevalence of Amblyopia in School-Aged Children and Variations by Age, Gender, and Ethnicity in a Multi-Country Refractive Error Study. Ophthalmology 2015; 122:1924-31. [PMID: 26278861 DOI: 10.1016/j.ophtha.2015.05.034] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 05/18/2015] [Accepted: 05/19/2015] [Indexed: 10/23/2022] Open
Abstract
PURPOSE To estimate the age-, gender-, and ethnicity-specific prevalence of amblyopia in children aged 5 to 15 years using data from the multi-country Refractive Error Study in Children (RESC). DESIGN Population-based, cross-sectional study. PARTICIPANTS Among 46 260 children aged 5 to 15 years who were enumerated from 8 sites in the RESC study, 39 551 had a detailed ocular examination and a reliable visual acuity (VA) measurement in 1 or both eyes. Information on ethnicity was available for 39 321 of these participants. This study focused on findings from the 39 321 children. METHODS The examination included VA measurements, evaluation of ocular alignment and refractive error under cycloplegia, and examination of the external eye, anterior segment, media, and fundus. MAIN OUTCOME MEASURES The proportion of children aged 5 to 15 years with amblyopia in different ethnic cohorts. Amblyopia was defined as best-corrected visual acuity (BCVA) of ≤20/40 in either eye, with tropia, anisometropia (≥2 spherical equivalent diopters [D]), or hyperopia (≥+6 spherical equivalent D), after excluding children with fundus or anterior segment abnormalities. RESULTS The overall prevalence of amblyopia was 0.74% (95% confidence interval, 0.64-0.83) with significant (P < 0.001) variation across ethnic groups: 1.43% in Hispanic, 0.93% in Chinese, 0.62% in Indian, 0.52% in Malay, 0.35% in Nepali, and 0.28% in African children. Amblyopia was not associated with age or gender. The most common cause of amblyopia was anisometropia. CONCLUSIONS In this study, the prevalence of amblyopia varied with ethnicity and was highest in Hispanic children and lowest in African children. Most cases were unilateral and developed before the age of 5 years. The impact of changes of definitions on prevalence estimates is discussed.
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Affiliation(s)
- Ou Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Ian G Morgan
- ARC Centre of Excellence in Vision Science and Research School of Biology, Australian National University, Canberra, Australia
| | - Leon B Ellwein
- National Eye Institute, National Institute of Health, Bethesda, Maryland
| | - Mingguang He
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China; Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye and Ear Hospital, East Melbourne, Australia.
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Abstract
Over the last 50 years, research into the developmental plasticity of the visual cortex has led to a growing understanding of first the causes and then of the underlying cellular mechanisms of amblyopia or 'lazy eye', the commonest childhood disorder of vision. While it is widely believed that amblyopia cannot be treated successfully after the age of about 7, recent animal studies have demonstrated that visual cortex plasticity can be restored or enhanced later in life, paving the way for new strategies for the treatment of amblyopia that attempt to remove molecular brakes on plasticity. In addition, both animal and human work has established that amblyopia is not simply a monocular deficit, and therefore the most promising new non-invasive approaches force the two eyes to cooperate as opposed to conventional procedures that severely penalise the good eye.
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Affiliation(s)
- Frank Sengpiel
- School of Biosciences and Neuroscience and Mental Health Research Institute, Cardiff University, Museum Avenue, Cardiff CF10 3AX, UK.
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43
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Saxena R, Puranik S, Singh D, Menon V, Sharma P, Phuljhele S. Factors predicting recurrence in successfully treated cases of anisometropic amblyopia. Indian J Ophthalmol 2014; 61:630-3. [PMID: 24343594 PMCID: PMC3959076 DOI: 10.4103/0301-4738.123144] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Context: Recurrence after successful treatment of amblyopia is known and understanding the risk factors could help effective management. Aim: To measure incidence of recurrence in successfully treated cases of anisometropic amblyopia and evaluate factors predicting it. Settings and Design: Cohort Study at a tertiary level institution. Materials and Methods: Successfully treated anisometropic amblyopes aged 4−12 years were followed up for 1 year after stopping therapy. Best corrected visual acuity (BCVA), refractive error, stereoacuity and contrast sensitivity were evaluated at baseline and follow-up. Statistical Analysis: Intergroup analysis with appropriate tests: Chi-square test, Fisher's exact test, Wilcoxon rank sum test and paired t-test. Results: One hundred and two patients with mean age at diagnosis 7.06 ± 1.81 years were followed-up for a mean duration of 1.0 ± 0.2 years. The mean pre-treatment BCVA (LogMAR score) at diagnosis was 0.73 ± 0.36 units which improved to 0.20 ± 0.00 with treatment and after 1 year of stopping treatment was 0.22 ± 0.07. Thirteen (12.74%) patients showed amblyopia recurrence during follow-up. Risk of recurrence was higher with older age of onset of treatment (6.64 ± 1.77 years without recurrence v/s 8.53 ± 1.39 years with recurrence, P = 0.0014). Greater extent of improvement of VA (P = 0.048) and final VA at stopping occlusion (P = 0.03) were associated with higher recurrence. Binocularity status or stereoacuity changes were not associated with risk of recurrence. Conclusions: Significant numbers of children suffer recurrence of amblyopia after stopping therapy. Older age, better BCVA after stopping therapy and greater magnitude of improvement in BCVA are important risk factors for recurrence. Careful follow-up is essential for early detection and management of recurrence.
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Affiliation(s)
- Rohit Saxena
- Squint and Neuro-Ophthalmology Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
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Abstract
Amblyopia is the most common cause of monocular visual impairment. Patching, which is modestly effective, is the current treatment of amblyopia in children. There is no clinically approved treatment for adults. The present study is a clinical trial (non-sham controlled and non-randomized) that assessed the efficacy of binocular training for improvement of the visual acuity in children and adults with amblyopia. Twenty-two amblyopic subjects ranging in age from 5 to 73 (mean: 36.2) years for whom patching and/or surgical treatments did not correct their visual impairment completed an average of 14.5 sessions of binocular training over a period of 4 to 6 weeks. Random dot kinematograms were presented dichoptically to the two eyes and the participants' task was to identify the direction of motion of the targets. Mean visual acuity improvement was 0.34 LogMAR (range: 0.1-0.58 LogMAR) and was shown to persist 6 months following the cessation of binocular training. Our study provides results in a large number of patients that confirm the clinical effectiveness of binocular training as a treatment for amblyopia in improving visual acuity in both children and adults. Moreover, this study is the first to demonstrate that the improvements in visual function were maintained for 6 months in the absence of any additional treatment.
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Affiliation(s)
- B Mansouri
- Section of Neurology, Department of Internal Medicine, University of Manitoba , Winnipeg, Manitoba , Canada and
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Joly O, Frankó E. Neuroimaging of amblyopia and binocular vision: a review. Front Integr Neurosci 2014; 8:62. [PMID: 25147511 PMCID: PMC4123726 DOI: 10.3389/fnint.2014.00062] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 07/12/2014] [Indexed: 11/13/2022] Open
Abstract
Amblyopia is a cerebral visual impairment considered to derive from abnormal visual experience (e.g., strabismus, anisometropia). Amblyopia, first considered as a monocular disorder, is now often seen as a primarily binocular disorder resulting in more and more studies examining the binocular deficits in the patients. The neural mechanisms of amblyopia are not completely understood even though they have been investigated with electrophysiological recordings in animal models and more recently with neuroimaging techniques in humans. In this review, we summarize the current knowledge about the brain regions that underlie the visual deficits associated with amblyopia with a focus on binocular vision using functional magnetic resonance imaging. The first studies focused on abnormal responses in the primary and secondary visual areas whereas recent evidence shows that there are also deficits at higher levels of the visual pathways within the parieto-occipital and temporal cortices. These higher level areas are part of the cortical network involved in 3D vision from binocular cues. Therefore, reduced responses in these areas could be related to the impaired binocular vision in amblyopic patients. Promising new binocular treatments might at least partially correct the activation in these areas. Future neuroimaging experiments could help to characterize the brain response changes associated with these treatments and help devise them.
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Affiliation(s)
- Olivier Joly
- MRC Cognition and Brain Sciences Unit Cambridge, UK ; Department of Experimental Psychology, University of Oxford Oxford, UK
| | - Edit Frankó
- Department of Neurodegenerative Disease, Institute of Neurology, University College London London, UK ; National Prion Clinic, National Hospital for Neurology and Neurosurgery, University College London Hospitals London, UK
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47
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Abstract
Amblyopia is a neurodevelopmental disorder of vision associated with decreased visual acuity, poor or absent stereopsis, and suppression of information from one eye.(1,2) Amblyopia may be caused by strabismus (strabismic amblyopia), refractive error (anisometropic amblyopia), or deprivation from obstructed vision (deprivation amblyopia). 1 In the developed world, amblyopia is the most common cause of childhood visual impairment, 3 which reduces quality of life 4 and also almost doubles the lifetime risk of legal blindness.(5, 6) Successful treatment of amblyopia greatly depends on early detection and treatment of predisposing disorders such as congenital cataract, which is the most common cause of deprivational amblyopia. Understanding the genetic causes of congenital cataract leads to more effective screening tests, early detection and treatment of infants and children who are at high risk for hereditary congenital cataract.
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Affiliation(s)
- Behzad Mansouri
- Mass Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston , Massachusetts , USA and
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Kulp MT, Cotter SA, Connor AJ, Clarke MP. Should amblyopia be treated? Ophthalmic Physiol Opt 2014; 34:226-32. [PMID: 24588534 DOI: 10.1111/opo.12124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marjean T Kulp
- The Ohio State University College of Optometry, Columbus, USA.
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Pallas A, Meyer CH, Mojon D. [Nintendo 3DS: technology, physiology and possible risks for children's eyes]. Ophthalmologe 2013; 110:263-6. [PMID: 23224123 DOI: 10.1007/s00347-012-2696-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
In March 2011 the new Nintendo 3DS went on sale in Switzerland and Germany. The game console features an attractive 3D display without the need of special glasses. By means of a so-called parallax barrier the depth perception can be increased or even turned off. In adults excessive use may cause symptoms such as headaches, dizziness or nausea. In children a visual impairment could be reinforced and an amblyopia could become manifest. Excessive, long hours of use especially in children could have its risks and the possible long-term effects remain unpredictable. On the other hand in the future it is likely that these kinds of 3D screens will be of considerable diagnostic value in orthoptics. The issue is likely to become a more important issue in everyday life in the future. As there is hardly any information available in the medical literature on this subject it is the aim of this article to provide an overview of the technology and physiology with the advantages and disadvantages.
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Affiliation(s)
- A Pallas
- Augenklinik, Kantonsspital St.Gallen, Rorschacherstr. 95, Haus 04, 9007, St. Gallen, Schweiz.
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Agervi P, Kugelberg U, Kugelberg M, Zetterström C. Two-year follow-up of a randomized trial of spectacles plus alternate-day patching to treat strabismic amblyopia. Acta Ophthalmol 2013; 91:678-84. [PMID: 22998746 DOI: 10.1111/j.1755-3768.2012.02536.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To compare spectacles plus alternate-day patching for 8 hr or more with spectacles plus patching for 8 hr or more 6 days weekly to treat strabismic amblyopia 1 year after a 1-year randomized trial. METHODS Forty children (mean age, 4.3 years) participated. Refractive correction was provided. The children were assigned to alternate-day patching for 8 hr or more or patching for 8 hr or more daily 6 days weekly. VA, binocular function, and refractive errors were measured after 2 years. The main outcome measure was the median VA change in the amblyopic eye after 2 years. RESULTS The median VA change in the amblyopic eye at the 2-year visit was significantly (p = 0.0453) greater with alternate-day patching (0.8 log unit) versus patching daily 6 days weekly (0.6 log unit). The final median VA in the amblyopic eyes was 0.0 logMAR in the alternate-day patching group and 0.1 logMAR in the daily patching group. Binocular function improved with both treatments. The median spherical equivalent (SE) refractive error increased in the fellow eyes (alternate-day patching, p < 0.0001; patching daily 6 days weekly, p = 0.0033); no change was found in the amblyopic eyes in either group. CONCLUSIONS The magnitude of the VA change 2 years after treatment with spectacles plus alternate-day patching for 8 hr or more was significantly greater than with spectacles plus daily patching for 8 hr or more 6 days weekly for strabismic amblyopia. However, the final median VA did not differ significantly between the two treatments.
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Affiliation(s)
- Pia Agervi
- St. Erik Eye Hospital, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, SwedenDepartment of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
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