Vision photoscreening of infants and young children in a primary care pediatric office: can it identify asymptomatic treatable amblyopic risk factors?

Approaches for delivery of refractive and optical care services in community and primary care settings

BACKGROUND

Uncorrected refractive error is a leading cause of vision impairment which, in most cases, can be managed with the appropriate spectacle correction. In 2021, the World Health Assembly endorsed a global target of a 40-percentage-point increase in effective coverage of refractive error by 2030. To achieve this global target, equitable access to refractive and optical services within community and primary care settings needs to be strengthened. This review will inform the development of technical guidance to support improvements in the testing and correction of refractive error among World Health Organization (WHO) member states.

OBJECTIVES

To determine the range of approaches for delivery of refractive and optical care services in community and primary care settings, and the methods employed for their evaluation.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase and Global Health databases, grey literature, and annual reports and websites of relevant organizations involved in eye-care delivery from January 2002 to November 2022 to identify approaches for refractive and optical service delivery.

SELECTION CRITERIA

We included observational and interventional studies, reviews, and reports from relevant organizations related to delivering refractive services and optical services for preschool and school-aged children and adults in community and primary care settings published between January 2002 and November 2022. We searched for studies and reports published within the last 20 years because vision impairment due to uncorrected refractive error has only recently become a public health and eye health priority, therefore we did not expect to find much relevant literature until after 2002.

DATA COLLECTION AND ANALYSIS

Two review authors screened titles, abstracts and full texts, and extracted data. We resolved any discrepancies through discussion. We synthesized data, and presented results as tables, figures, and case studies. This project was led by the World Health Organization (WHO) Vision and Eye Care Programme.

MAIN RESULTS

We identified 175 studies from searches of databases and grey literature, 146 records from company reports, and 81 records from website searches of relevant organizations that matched our inclusion criteria. Delivery approaches for refractive and optical services in community care included school-based, pharmacy, and outreach models, whereas primary care approaches comprised vision centre, health centre, and a combination of vision or health centre and door-to-door delivery. In community care, school-based and outreach approaches were predominant, while in primary care, a vision-centre approach was mainly used. In the WHO African region, the school-based and outreach approaches were mainly reported while, in the Americas, the outreach approach was mostly used. Very few approaches for service delivery were reported in the WHO Eastern Mediterranean region. Prominent gaps exist in the evaluation of the approaches, and few studies attempted to evaluate the approaches for delivery of refractive and optical care services.

AUTHORS' CONCLUSIONS

We comprehensively describe a range of approaches for delivery of refractive and optical services in community and primary care. Further evaluation of their effectiveness will better inform the application of these service-delivery approaches. The study outcomes will help guide WHO member states in strengthening refractive and optical services at community and primary care levels.

FUNDING

This scoping review was supported by the Vision and Eye care Programme, World Health Organization and ATscale Global Partnership.

REGISTRATION

The protocol of this scoping review was published in the Open Source Framework.

Automated vision screening of children using a mobile graphic device

BACKGROUND/OBJECTIVE

Can measuring interocular brightness disparity, acuity, and colour vision classify children with amblyopia?

SUBJECTS/METHODS

Two hundred eight subjects (3-14 years) were recruited for a prospective, observational protocol to measure interocular brightness disparity, uniocular acuities with and without a pinhole, and colour vision using an iPad. Subjects looked through polarizing filters and chose the brighter of two spaceships to measure interocular brightness disparity. The differential brightness of image pairs was varied through a staircase algorithm until equal brightness was perceived. Acuities and colour vision were tested with tumbling Es and AO-HRR colour plates, respectively. Unilateral amblyopia was later confirmed in two subjects.

RESULTS

Binocular brightness balance on the iPad detected amblyopes with 100% sensitivity and specificity. Using 20/30 as cutoff for normal acuity, 1 of the amblyopes was detected, and non-amblyopes were excluded by visual acuity pinhole testing. The mean difference between iPad and E-Chart visual acuities with pinhole was 0.02 logMAR with limits of agreement from -0.08 to +0.11 logMAR. iPad and printed plates Colour vision testing produced identical results. Testing times were brief and exit pleasure responses were positive. Mean and range testing times for Brightness Sense, Colour vision, and Visual Acuity were 32.7 s (range = 12-63 s), 52.8 min (range = 17-95 s), and 88.75 s (range = 41-188 s), respectively.

CONCLUSIONS

Interocular brightness disparity, acuity, and colour vision can be measured in children as young as 3 years old solely through playing a game on a mobile device. Interocular brightness disparity is a sensitive and specific method to detect unilateral amblyopia.

Photoscreening for amblyopia risk factors assessment in young children: A systematic review with meta-analysis

PURPOSE

Amblyopia is a leading cause of preventable and treatable vision loss in the pediatric population. Instrument-based screening of amblyopia-risk factors is being widely adopted but the audit of its results is still lacking. We sought to review the existing evidence regarding the outcomes of photoscreening applied to children under the age of three years.

METHODS

A three-database search (Pubmed, ISI Web of Science, and Scopus) was performed from inception to March 2021. A meta-analysis of proportions was conducted to summarize the referral rate, untestable rate and positive predictive value (PPV).

RESULTS

Thirteen studies were selected among 705 original abstracts. The quantitative analysis included twelve studies enrolling 64,041 children. Of these, 13% (95%CI: 7-19%) were referred for further confirmation of the screening result. Astigmatism was the most common diagnosis both after screening and after ophthalmologic assessment of referred children. The pooled untestable rate and PPV were 8% (95%CI: 3-15%) and 56% (95%CI: 40-71%), respectively.

CONCLUSION

There is no global consensus on the optimal age, frequency or what magnitude of refractive error must be considered an amblyopia-risk factor. Optimization of referral criteria is therefore warranted.

Scope and costs of autorefraction and photoscreening for childhood amblyopia-a systematic narrative review in relation to the EUSCREEN project data

Background

Amblyopia screening can target reduced visual acuity (VA), its refractive risk factors, or both. VA testing is imprecise under 4 years of age, so automated risk-factor photoscreening appears an attractive option. This review considers photoscreening used in community services, focusing on costs, cost-effectiveness and scope of use, compared with EUSCREEN project Country Reports describing how photo- and automated screening is used internationally.

Methods

A systematic narrative review was carried out of all English language photoscreening literature to September 10th 2018, using publicly available search terms. Where costs were considered, a CASP economic evaluation checklist was used to assess data quality.

Results

Of 370 abstracts reviewed, 55 reported large-scale community photoscreening projects. Five addressed cost-effectiveness specifically, without original data. Photoscreening was a stand-alone, single, test event in 71% of projects. In contrast, 25 of 45 EUSCREEN Country Reports showed that if adopted, photoscreening often supplements other tests in established programmes and is rarely used as a stand-alone test. Reported costs varied widely and evidence of cost-effectiveness was sparse in the literature, or in international practice. Only eight (13%) papers compared the diagnostic accuracy or cost-effectiveness of photoscreening and VA testing, and when they did, cost-effectiveness of photoscreening compared unfavourably.

Discussion

Evidence that photoscreening reduces amblyopia or strabismus prevalence or improves overall outcomes is weak, as is evidence of cost-effectiveness, compared to later VA screening. Currently, the most cost-effective option seems to be a later, expert VA screening with the opportunity for a re-test before referral.

Successes and shortfalls of community Plusoptix photoscreening: results from the iSee study in Southwestern Ontario

OBJECTIVE

The purpose of this work is to provide the final results from a community-wide photoscreening program in Southwestern Ontario for children aged 18 to 72 months, and to estimate the prevalence of amblyogenic risk factors in this population.

STUDY DESIGN

Prospective, multisite photoscreening program.

PARTICIPANTS

5959 children aged 18-72 months were recruited and screened in Southwestern Ontario at 210 locations over a period of 3 years and 4 months.

METHODS

Ophthalmic screening examinations were performed with the Plusoptix S12 photoscreener. The threshold for the referral criteria used was the manufacturer's criteria on receiver operating characteristics 4.

RESULTS

The screening was negative in 5386 children (90.4%), positive in 403 (6.8%), and unreadable in 170 (2.9%); 42% of all screened children were ≤36 months old. The estimated amblyogenic risk factor prevalence of anisometropia was 4.0%, astigmatism was 3.1%, hyperopia was 1.1%, myopia was 0.4%, and strabismus was 0.4%. Of the 403 referred children, 99 (24.5%) completed a formal eye examination based on the responses returned to the study site.

CONCLUSIONS

This is the first Canadian study that provides data on amblyogenic risk factors based on a volunteer-led photoscreening program. Photoscreening is an effective screening tool, particularly for pre-school-aged children; however, the lack of mandatory follow-up to ensure that children receive proper treatment based on cycloplegic refraction reduces the efficacy of screening.

Refinement strategies in photoscreening for the detection of amblyopia risk factors in 12-to-24-month-old children

PURPOSE

To establish an appropriate clinical protocol for early photoscreening in 12-to-24-month-old children at pediatric well-baby clinics.

METHODS

This prospective study included a total of 277 children aged 12-24 months who visited a pediatric well-baby clinic. All participants underwent: 1) inquiry of medical history; 2) photoscreening with PlusoptiX A12; and 3) comprehensive ophthalmologic examinations. The optimal referral cut-off point for PlusoptiX was determined by receiver operating characteristic analyses. A high-risk subgroup was defined as having a birth weight <3000 g or a history of major systemic diseases, based on the results of multivariable risk factor analysis from children's medical history. A strategy of selective photoscreening focusing on the high-risk subgroup was evaluated. The main outcome measures included sensitivity, specificity, and positive and negative predictive values.

RESULTS

The prevalence of amblyopia risk factors in our study population was 12.3%. A total of 172 children (62.1%) were assigned to the high-risk subgroup. Compared with the nonselective photoscreening of all 277 children, selective photoscreening of the high-risk children yielded a higher positive predictive value (59.6% vs. 46.7%, p = 0.001) while showing no difference in sensitivity (82.3% vs. 85.3%, p = 0.32), specificity (92.2% vs, 86.4%, p = 0.05), and negative predictive value (97.4% vs. 97.6%, p = 0.50).

CONCLUSION

At pediatric well-baby clinics, selective photoscreening among 12-to-24-month-old children with a birth weight <3000 g or a history of major systemic diseases helped reducing the number of children need to be screened and conserving medical resources yet identifying children at risk for timely eye care.

Vision Screening in Infants Attending Immunization Clinics in a Developing Country

Background: Vision screening in infants is an important part of the medical care of children as some eye abnormalities, if not treated in the first few months or years of life, can lead to irreversible vision loss. Objective: The objective of this cross-sectional, descriptive study was to identify ocular anomalies among infants attending immunization clinics in Nigeria and refer promptly and appropriately. Methodology: Infants were screened across 6 immunization clinics. Screening activities included relevant ocular history, vision assessment, external ocular examination, ocular motility, Hirschberg's test, pupil examination, and the red reflex test. Infants with abnormal findings were referred for comprehensive eye examination. Result: Of the 142 infants who underwent vision screening, 29 were referred. These referrals were either as a result of ocular abnormalities (n = 22) or presence of risk factors from history (n = 7). The prevalence of ocular abnormalities was 15.5% and neonatal conjunctivitis (38%), was the commonest ocular abnormality found. Others were bacterial conjunctivitis (14%), nasolacrimal duct obstruction (14%), strabismus (14%), capillary hemangiomas (10%), iris nevi (5%), and vernal keratoconjunctivitis (5%). Of the 7 infants referred based on history alone, 6 (85.7%) had a history of prematurity. Conclusion: Conjunctivitis, strabismus, congenital nasolacrimal duct obstruction, and capillary hemangioma are some of the prevalent disorders seen in infants at immunization clinics in Nigeria. Babies at risk of retinopathy of prematurity (preterm birth and oxygen therapy) can be identified. Immunization clinics can serve as good points of vision screening for infants in developing countries to facilitate prompt referral and treatment.

Comparison of the pediatric vision screening program in 18 countries across five continents

PURPOSE

Incorporating mass pediatric vision screening programs as part of a national agenda can be challenging. This review assessed the implementation strategy of the existing pediatric vision screening program.

METHODS

A search was performed on PubMed, EBSCO host MEDLINE Complete, and Scopus databases encompassing the past ten years for mass pediatric screening practice patterns that met the selection criteria regarding their objectives and implementation. Results were analyzed from 18 countries across five continents.

RESULTS

Eight countries (44%) offered screening for distance visual acuity only, where the majority of the countries (88%) used either Snellen or Tumbling E chart. High-income countries initiated screening earlier and applied a more comprehensive approach, targeting conditions other than reduced vision only, compared with middle-income countries. Chart-based testing was most commonly performed, with only three countries incorporating an instrument-based approach. Lack of eyecare and healthcare practitioners frequently necessitated the involvement of non-eyecare personnel (94%) as a vision screener including parent, trained staff, and nurse.

CONCLUSIONS

Implementation of a vision screening program was diverse within countries preceded by limited resources issues. Lack of professional eyecare practitioners implied the need to engage a lay screener. The limitation of existing tests to detect a broader range of visual problems at affordable cost advocated the urgent need for the development of an inexpensive and comprehensive screening tool.

Amblyopia Risk Factors in Premature Children in the First 3 Years of Life

PURPOSE

To determine the incidence of amblyopia risk factors during the first 3 years of life in premature children.

METHODS

This prospective cohort included 145 premature children (gestational age of less than 37 weeks) who were evaluated for amblyopia risk factors every 6 months until age 3 years. The incidence rate, cumulative incidence, and prevalence of any amblyopia risk factor were assessed in retinopathy of prematurity (ROP) and non-ROP screened groups. Multivariate logistic regression was performed to evaluate variables associated with the development of an amblyopia risk factor.

RESULTS

The 3-year incidence rates of amblyopia risk factors were similar between the non-ROP and ROP screened groups (18 versus 19 cases per 1,000 person-years, respectively). The 3-year cumulative incidence was also similar: 32% (95% confidence interval [CI]: 18 to 47) in the non-ROP and 14% (95% CI: 5 to 28) in the ROP screened group (P > .05). In the ROP screened group, the prevalence rates were 20% or greater at most time points. In the non-ROP screened group, the prevalence rates were 11% to 14% during the first 18 months and increased to more than 20% at 24 months and thereafter. Astigmatism was the most prevalent amblyopia risk factor in both groups (7% to 18%).

CONCLUSIONS

The incidence of amblyopia risk factors was not significantly different between non-ROP and ROP screened children in our cohort. The prevalence of refractive errors among premature non-ROP screened children was higher than that reported in childhood in the literature. It may be appropriate to screen all children with a history of prematurity for refractive errors around 24 months of age. [J Pediatr Ophthalmol Strabismus. 2019;56(2):88-94.].

Validation of photoscreening technology in the general pediatrics office: a prospective study

BACKGROUND

Photoscreening instruments have been widely validated in pediatric ophthalmology clinics and field studies; however, validation by general pediatricians is lacking. We performed the first prospective, multisite evaluation of a commercially available photoscreener in the medical home.

METHODS

Eleven practices in Middle Tennessee recruited over 3,100 children between 12 months and 5 years to be screened at well-child examinations. Participants were those who received a "refer" result; controls received a "pass." Referred children received a comprehensive eye examination with cycloplegic retinoscopy. A subset of control children underwent eye examinations in an attempt to determine sensitivity and specificity.

RESULTS

The overall referral rate was 10%. Amblyopia risk factors (ARFs) were confirmed in 47% of referred children, with positive predictive values (PPVs) of 77.8% for suspected hyperopia, 60% for myopia, 50% for anisometropia, and 44.8% for astigmatism by the 2013 guidelines of the American Association of Pediatric Ophthalmology and Strabismus Vision Screening Committee. Using the 2003 guidelines, the overall PPV was 60.3%; PPVs were determined for suspected hyperopia (77.8%), myopia (60%), anisometropia (67.6%), and astigmatism (61.2%). Of referred children who received follow-up, 18 (13.2%) had amblyopia. PPVs for children ≤36 months (n = 79) did not differ from those 37-72 months (n = 57). No child who passed screening and had a follow-up examination had any ARFs.

CONCLUSIONS

Our results replicate those of previously published field studies and support recent United States Preventive Services Task Force and American Academy of Pediatrics position statements. They provide prospective evidence that photoscreening is an effective tool for children aged 12-72 months.

Visual System Assessment in Infants, Children, and Young Adults by Pediatricians

Appropriate visual assessments help identify children who may benefit from early interventions to correct or improve vision. Examination of the eyes and visual system should begin in the nursery and continue throughout both childhood and adolescence during routine well-child visits in the medical home. Newborn infants should be examined using inspection and red reflex testing to detect structural ocular abnormalities, such as cataract, corneal opacity, and ptosis. Instrument-based screening, if available, should be first attempted between 12 months and 3 years of age and at annual well-child visits until acuity can be tested directly. Direct testing of visual acuity can often begin by 4 years of age, using age-appropriate symbols (optotypes). Children found to have an ocular abnormality or who fail a vision assessment should be referred to a pediatric ophthalmologist or an eye care specialist appropriately trained to treat pediatric patients.