Efficacy of vision therapy for unilateral refractive amblyopia in children aged 7-10 years

Add-on perceptual learning on refractive amblyopia in children

AIM

To evaluate the visual outcomes of standard amblyopic treatment add-on training via perceptual learning in refractive amblyopic children and to identify the risk factors for treatment failure.

METHODS

Retrospective charts were reviewed in children with refractive amblyopia who received standard treatment and add-on Cambridge Visual Stimulator (CAM) training. The add-on CAM group that was enrolled had worn full-corrected glasses for at least 2mo before training. A control group received only the standard treatment. Treatment success was defined as best-corrected visual acuity (BCVA) ≥20/25. The age, sex, initial BCVA, refractive errors, sessions and duration of training, and final BCVA were recorded.

RESULTS

A total of 209 children (129 children in add-on CAM group and 80 children in control group) were enrolled. Seventy-six percent of unilateral and 87% of bilateral amblyopic children achieved treatment success. In children with unilateral or bilateral moderate amblyopia, the duration to reach BCVA ≥20/25 was significantly shorter in add-on CAM group than in control group. Poor initial BCVA (P<0.001) and high astigmatism (P=0.007) were risk factors for treatment failure after add-on CAM training. Age, sex, and types of refractive error were not associated with treatment success.

CONCLUSION

Add-on CAM training is an effective strategy for visual improvement and can shorten the treatment course when the effect of standard treatment is limited in amblyopic children.

Professional perspective of vision therapy worldwide among optometrists and ophthalmologists

CLINICAL RELEVANCE

Perception of optometrists and ophthalmologists of vision therapy (VT) as well as their methods for performing the sessions is of great importance for understanding the problems that professionals face and what should be improved in their clinical practice.

BACKGROUND

The objective of this study was to determine the perception of VT and protocols used by eye care professionals globally.

METHODS

A cross-sectional study was performed among eye care professionals internationally. The participants completed via online (Google Forms) a questionnaire of 40 questions on their perception and clinical practice of VT. The survey only permitted one answer per email address and was only collected if professionals gave their consent to participate.

RESULTS

A total of 205 professionals from 43 countries answered the questionnaire (171 optometrists and 34 ophthalmologists). Accommodation and convergence problems were the main indication reported for VT (47.8%), followed by amblyopia (26.3%). The principal negative factor associated to VT was the limited number of professionals dedicated to this field (55.6%). The most common program of VT was the combination of VT sessions at home and at office (85.5%), with a great variability in terms of duration. Few professionals made use of the new technologies when programming VT, such as eye trackers (2.7%) or virtual reality (6.4%). European professionals surveyed had a more negative perception of VT (p < 0.031).

CONCLUSIONS

Eye care professionals globally perceive VT as a scientifically based procedure. Overall, they believe that it has low recognition and prestige, especially ophthalmologists. A great variability in the programming of VT sessions was found, which highlights the need for standardised protocols that professionals could follow in their clinical practice.

Childhood amblyopia: A systematic review of recent management options

This study reviews the current information on treatment of childhood amblyopia, with the goal of improving visual functions. The authors searched various online databases including PubMed, Web of Science, ProQuest, Scopus, Google Scholar, Ebsco, and Medline. The articles, published between 2002 and 2023, included in this study were used to assess the different modalities for the management of different types of childhood amblyopia. The final systematic review included 41 studies from different countries, covering 4060 children with a mean age 6.8 ± 124 years. The findings showed that childhood amblyopia commonly treated through a systemic approach, i.e., starting with treatment of refractive errors with given optical adaptation time, followed by visually stimulating amblyopic eye by covering the dominant eye with patching, Atropine or Bangerter filters. Refractive adaptation period of 18-22 weeks has proven to show a significant improvement in visual acuity. It has been confirmed that 2 h patching is effective for the first time treated amblyopes, and if there is no improvement, increase the period to 6 h daily. Novel methods that improve binocular function such as dichoptic, perceptual training, video gaming, and drugs that facilitate visual neuroplasticity, are useful in the treatment of amblyopia that is not responsive to conventional therapy. The study concludes that significant evidence show that childhood amblyopia is treated through a systemic approach. Starting from correcting refractive errors with a period of optical adaptation, followed by patching therapy and atropine penalization. New methods that improve the binocular functions and medications that facilitate visual neuroplasticity have found to be useful in the treatment of amblyopia that is not responsive to conventional treatment.

Cost-effectiveness of screening for amblyopia among kindergarten children in China

OBJECTIVE

Current cost-effectiveness analyses of amblyopia screening are mainly from western countries. It remains unclear whether it is cost-effective to implement a preschool amblyopia screening programme in China. Our study aimed to evaluate the cost-effectiveness of a hypothetical kindergarten-based amblyopia screening versus non-screening among 3-year-old children.

METHODS

We developed a decision tree combined with a Markov model to compare the cost and effectiveness of screening versus non-screening for 3-year-old children from a third-party payment perspective. The primary outcomes were quality-adjusted life years (QALYs) and the incremental cost-effectiveness ratio (ICER). Costs were obtained from expert opinions in different regions of China. Transition probabilities and health utilities were mainly based on published literature and open sources. Sensitivity analyses were performed to assess the impact of parameters' uncertainty on results.

RESULTS

Base-case analysis demonstrated that the ICER of screening versus non-screening was $17,466/QALY, well below the WTP threshold ($38,223/QALY) for China. One-way sensitivity analysis showed that the prevalence of amblyopia, the transition probability per year from untreated amblyopia to healthy, and the discount rate were the top three factors. The likelihood of cost-effectiveness of screening compared with non-screening was 92.56%, according to probabilistic sensitivity analysis. Scenario analysis also indicated that ICER was lower than the WTP threshold even if the time horizon was shortened or the screening was delayed to the age of 4 or 5.

CONCLUSIONS

Amblyopia screening could be considered a cost-effective strategy compared to non-screening for 3-year-old children in China. Screening for children at the age of 4 or 5 may even yield better results.

Supervised dichoptic gaming versus monitored occlusion therapy for childhood amblyopia: Effectiveness and efficiency

PURPOSE

To compare the effectiveness and efficiency of supervised dichoptic action-videogame play to occlusion therapy in children with amblyopia.

METHODS

Newly diagnosed children with amblyopia aged 4-12 years were recruited, excluding strabismus >30PD. After 16 weeks of refractive adaptation children were randomized to gaming 1 h/week supervised by the researcher, or electronically monitored occlusion 2 h/day. The gaming group played a dichoptic action-videogame using virtual reality goggles, which included the task of catching a snowflake presented intermittently to the amblyopic eye. Contrast for the fellow eye was self-adjusted until 2 identical images were perceived. The primary outcome was visual acuity (VA) change from baseline to 24 weeks.

RESULTS

We recruited 96 children, 29 declined and 2 were excluded for language or legal issues. After refractive adaptation, 24 of the remaining 65 no longer met the inclusion criteria for amblyopia, and 8 dropped out. Of 16 children treated with gaming, 7 (6.7 years) completed treatment, whereas 9 younger children (5.3 years) did not. Of 17 treated with occlusion, 14 (5.1 years) completed treatment and 3 (4.5 years) did not. Of 5 children with small-angle strabismus, 3 treated with occlusion completed treatment and 2 treated with gaming did not. Median VA improved by 0.30 logMAR (IQR 0.20-0.40) after gaming, 0.20 logMAR (0.00-0.30) after occlusion (p = 0.823). Treatment efficiency was 1.25 logMAR/100 h (range 0.42-2.08) with gaming, 0.08 (-0.19-0.68) with occlusion (p < 0.001).

CONCLUSION

Dichoptic gaming seems a viable alternative for older children with refractive amblyopia after glasses adaptation. Treatment efficiency with gaming under continuous supervision was 15 times higher than with occlusion at home.

Impact of active vision therapy compared to conventional patching therapy on visual acuity and stereoacuity in children with amblyopia

PURPOSE

To compare improvements in visual acuity (VA) and stereoacuity between active vision therapy (AVT) and conventional patching therapy in children with amblyopia.

METHODS

This study included 65 children aged 5 to 16 years (mean age±SD, 11.00±3.29 years) with unilateral amblyopia. Among them, 31 children underwent active vision therapy (AVT group), and 34 children underwent conventional patching therapy (patching group). AVT group underwent three sequential phases of AVT: Monocular phase (pursuit, saccades, fixation, visuomotor, eye-hand coordination, and central peripheral activities), biocular phase (diplopia awareness, antisuppression, monocular fixation in a binocular field, accommodative activities, bilateral integration, and fine motor activities) and binocular phase (fusion and stereopsis). Patching group patched their fellow eyes as per guidelines by Pediatric Eye Disease Investigator Group. Best-corrected monocular VA and stereoacuity were measured at baseline and after three months of therapy in both groups.

RESULTS

There were significant improvements in the mean acuities in amblyopic eye (AE) in both AVT (0.32±0.11 logMAR, p <0.001) and patching groups (0.27±0.19 logMAR, p ˂ 0.001). However, there was no significant difference in mean acuity gains in AE between AVT and patching groups (p = 0.059). Mean gains in stereoacuities (log seconds of arc) were statistically significant in both AVT (0.81±0.34, p < 0.001) and patching groups (0.32±0.34, p < 0.001). The stereoacuity gain in the AVT group was significantly higher compared to patching group (p < 0.001).

CONCLUSION

Active vision therapy had a better impact than conventional patching therapy in terms of improvement of stereoacuity but not in terms of VA when used for treating children with amblyopia.

Current Developments in the Management of Amblyopia with the Use of Perceptual Learning Techniques

Background and Objectives: Amblyopia is a neurodevelopmental disorder caused by interocular suppression of visual input, affecting visual acuity, stereopsis, contrast sensitivity, and other visual functions. Conventional treatment comprises occlusion of the sound eye. In recent years, novel therapies that deploy perceptual learning (PL) principles have been introduced. The purpose of this study is to assess the latest scientific data on this topic. Materials and Methods: For this purpose, we conducted a literature search for relevant studies published during the previous 4 years (2020-2023). Results: A plethora of visual perceptual learning protocols have been recently developed. Dichoptic video games, contrast rebalanced movies, and online perceptual training platforms are the main formats. Perceptual learning activates neuroplasticity, overcomes interocular suppression, and improves the visual impairments induced by amblyopia. Conclusions: This novel treatment is effective in both children and adults, as well as in patients non-responding to patching.

Treatment Outcome of Occlusion for Unilateral Amblyopia in Saudi Children 6-12 Years Old

PURPOSE

The purpose of this study was to estimate the rate and review determinants of successful therapy for unilateral amblyopia in children.

METHODS

This prospective cohort consisted of Saudi children aged 6-12 who received amblyopia therapy between 2020 and 2022. Best-corrected visual acuity (BCVA) in the amblyopic eye improved to reach the BCVA of the fellow eye at follow-up visits, or BCVA in the amblyopic eye improved and remained stable over three follow-up visits. Demographic and ocular characteristics were associated with the outcome.

RESULTS

In 30 children, the median BCVA at presentation and the last follow-up was 0.8 logMAR (interquartile range [IQR]: 0.6; 1.0) and 0.45 logMAR (IQR: 0.3; 0.6), respectively. The success rate of amblyopia therapy was 80% (95% confidence interval: 65.7; 94.3). It was 100%, 76.5%, and 77.8% in eyes with anisometropic, strabismic, and mixed types of amblyopia, respectively. Amblyopia grade (P = 0.177), type of amblyopia (P = 0.96), and spectacles as therapy in the past (P = 0.09) were not significantly associated with the successful out. The duration of follow-up was significantly longer in those with unsuccessful outcomes (P = 0.05). Excellent compliance for occlusion was observed in 62.5% of children with successful outcomes. In 14 (46.7%) children, BCVA was ≤0.3 logMAR BCVA at the last follow-up. Two-line improvement in amblyopic eyes was in 26 (86.7%) children at the last follow-up compared to BCVA at presentation.

CONCLUSION

Occlusion therapy complemented using glasses in older children also significantly improved visual recovery in amblyopic eyes.