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

Screening, Diagnosis, and Treatment of Pediatric Ocular Diseases

Vision is an important aspect of a child's quality of life and intellectual, social, and emotional development. Disruptions to vision during infancy and early childhood can cause lifelong vision impairment or blindness. However, early identification and treatment of eye disease can prevent loss of sight and its consequent long-term effects. Therefore, screening guidelines exist to guide physicians in detecting the most common threats to sight in the different stages of infancy and childhood. This review describes common causes of pediatric vision impairment, the recommended screening guidelines for diagnosing them, and current treatment modalities.

Macular pigment optical density of hyperopic anisometropic amblyopic patients measured by fundus reflectometry

Purpose

Hyperopic anisometropia is a major cause of amblyopia and may be associated with macular pigment optical density (MPOD) reduction. To explore whether the MPOD changes in hyperopic anisometropic amblyopia, we measured the MPOD using fundus reflectometry in eyes with hyperopic anisometropic amblyopia and normal vision.

Methods

This was a cross-sectional study conducted from January 2017 to June 2017. Forty subjects (25 males and 15 females) between the ages of 6 and 10 years were recruited. The subjects' eyes were divided into two groups: amblyopic eyes (best-corrected visual acuity (BCVA) not more than 20/25 or BCVA of two eyes differing by two or more lines) and fellow eyes. All enrolled subjects underwent a comprehensive ophthalmic examination, including extraocular motility assessment, cover-uncover testing, and refractive error (noncycloplegic), BCVA, axial length (AL), macular foveal thickness (MFT) and MPOD (Visucam^® 200, Carl Zeiss Meditec AG, Germany).

Results

The MPOD of amblyopic and fellow eyes was 0.12 ± 0.03 log units and 0.13 ± 0.04 log units, respectively, with a significant difference (P = 0.026). The MFT of amblyopic and fellow eyes was 241.28 ± 13.95 and 237.13 ± 16.02 μm, respectively, revealing that the MFT was significantly higher in amblyopic eyes than in fellow eyes (P = 0.028). Conversely, there was no correlation between the MPOD and MFT in the two groups.

Conclusions

This study is the first to report that the MPOD is decreased in hyperopic anisometropic amblyopia. In this study, no correlation between the MPOD and MFT was found. In the future, factors that induce a decrease in the MPOD in eyes with hyperopic anisometropic amblyopia should be explored in a large-sample study with follow-up observation.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Efficacy of vision-based treatments for children and teens with amblyopia: a systematic review and meta-analysis of randomised controlled trials

Objective

To identify differences in efficacy between vision-based treatments for improving visual acuity (VA) of the amblyopic eye in persons aged 4-17 years old.

Data sources

Ovid Embase, PubMed (Medline), the Cochrane Library, Vision Cite and Scopus were systematically searched from 1975 to 17 June 2020.

Methods

Two independent reviewers screened search results for randomised controlled trials of vision-based amblyopia treatments that specified change in amblyopic eye VA (logMAR) as the primary outcome measure. Quality was assessed via risk of bias and GRADE (Grading of Recommendations, Assessment, Development, and Evaluations).

Results

Of the 3346 studies identified, 36 were included in a narrative synthesis. A random effects meta-analysis (five studies) compared the efficacy of binocular treatments versus patching: mean difference -0.03 logMAR; 95% CI 0.01 to 0.04 (p<0.001), favouring patching. An exploratory study-level regression (18 studies) showed no statistically significant differences between vision-based treatments and a reference group of 2-5 hours of patching. Age, sample size and pre-randomisation optical treatment were not statistically significantly associated with changes in amblyopic eye acuity. A network meta-analysis (26 studies) comparing vision-based treatments to patching 2-5 hours found one statistically significant comparison, namely, the favouring of a combination of two treatment arms comparing combination and binocular treatments, against patching 2-5 hours: standard mean difference: 2.63; 95% CI 1.18 to 4.09. However, this result was an indirect comparison calculated from a single study. A linear regression analysis (17 studies) found a significant relationship between adherence and effect size, but the model did not completely fit the data: regression coefficient 0.022; 95% CI 0.004 to 0.040 (p=0.02).

Conclusion

We found no clinically relevant differences in treatment efficacy between the treatments included in this review. Adherence to the prescribed hours of treatment varied considerably and may have had an effect on treatment success.

Atropine in topical formulations for the management of anterior and posterior segment ocular diseases

INTRODUCTION

Atropine is an old-known drug which is gaining increasing attention due to the myriad of therapeutic effects it may trigger on eye structures. Nevertheless, novel applications may require more adequate topical formulations.

AREAS COVERED

This review aims to gather the existing knowledge about atropine and its clinical applications in the ophthalmological field when administered topically. Atropine ocular pharmacokinetics is paid a special attention, including recent evidences of the capability of the drug to access to the posterior segment. Ocular bioavailability and systemic bioavailability are counterbalanced. Finally, limitations of traditional dosage forms and potential advantages of under investigation delivery systems are analyzed.

EXPERT OPINION

Mydriasis and cyclopegia have been widely exploited for eye examination, management of anterior segment diseases, and more recently as antidotes of chemical weapons. Improved knowledge on drug receptors and related pathways explains atropine repositioning as an outstanding tool to prevent myopia. The ease with which atropine penetrates ocular tissues is a double edged sword, that is, while it ensures therapeutic levels in the posterior segment, the unspecific distribution causes a wide variety of untoward effects. The design of formulations that can selectively deliver atropine to the target tissue for each specific application is an urgent unmet need.