Vision screening in children by Plusoptix Vision Screener compared with gold-standard orthoptic assessment

Referral rate for refractive amblyopia using automated vision screening in school children in Beirut, Lebanon

BACKGROUND

Amblyopia is one of the most prevalent causes of decreased vision in children and can be effectively diagnosed at an early stage through vision screening. Untreated vision impairments during childhood have lasting implications on academic achievements. The purpose of this study was to compare referral rates when applying different referral criteria including the AAPOS 2021 exam failure levels and the Arnold "medium" 2022 Instrument Referral Criteria.

METHODS

Automated vision screening was conducted in four selected schools (two private and two public) in Beirut, Lebanon. Children aged 3-6 years old were targeted. The Plusoptix A12 Refractometer was utilized to perform vision screening. Referral rate was computed for the American Association of Pediatric Ophthalmology and Strabismus (AAPOS) age-based criteria applied to the Plusoptix A12 and compared to the Arthur exam failure criteria and 4 instrument referral criteria (Arnold Medium and Specific, Matta & Silbert, and Alaska Blind Child Discovery). Referral rates were also compared between public and private schools based on the AAPOS criteria.

RESULTS

A total of 308 children were screened: 114 students from public schools and 194 students from private schools. The gender distribution in the two groups was similar (46% females in public schools and 48% in private schools); 34% of the studied population were under 4 years old, while 66% were ≥4 years. The referral rate using the AAPOS 2021 criteria was 22%. There was a significant difference in referral rates overall and across the different types of refractive error when compared with the other referral criteria. Referral rate using the ABCD criteria was similar (17.9%). Referral rates were higher when applying Arthur criteria (28.2%) and Matta & Silbert criteria (41.9%), while the Arnold Medium and Specific criteria had the lowest referral rates (11.4%, 9.1%). The most common refractive error across all criteria was astigmatism. The overall referral rate using the AAPOS 2021 criteria was 22% and this differed significantly by school type, with a rate of 36% for public schools and 14% for private schools (p < 0.001). Spherical equivalent was also higher in public schools. Among children needing referral, 40.6% were already wearing spectacles at the time of examination and this differed by school type (4.9% of children referred from public schools and 92.8% of children referred from private schools).

CONCLUSION

Photoscreener referral rate and the detection of the different types of refractive errors varies significantly according to the referral criteria used. Careful consideration of psychometric characteristics of referral criteria is important and the use of device-specific age-based criteria is recommended. In our cohort, the most common refractive error was astigmatism. The overall rate of referral was 22% according to the AAPOS age-based exam failure referral criteria, which differed from referral rates applying other validated instrument referral criteria in the literature. The referral rate and spherical equivalent were higher in public schools compared to private schools.

Evaluation of the diagnostic parameters of the amblyopia and risk factors for amblyopia screening protocol in 3-year-olds according to recommendations from the French Association for Pediatric Ophthalmology and Strabismus (AFSOP) compared with reference ophthalmological examination: the ORTHOPHTALMO study

Introduction: The ORTHOPHTALMO study aims to evaluate the diagnostic parameters of the screening protocol for amblyopia and risk factors for amblyopia in 3-year-olds recommended in 2019 by the French Association for Pediatric Ophthalmology and Strabismus (AFSOP). This protocol uses visual acuity, photoscreening refraction, and cover test examination performed by an orthoptist. Patient referral to an ophthalmologist is only according to recommended referral criteria. Methods: A prospective, single-center study was performed between September 2020 and June 2021 on a consecutive series of 3-year-olds consulting the Ophthalmology Centre of Clinique Rive Gauche, Toulouse, France, for vision screening. Patients were first examined by an orthoptist following the screening protocol recommended by AFSOP. All patients were then systematically examined by an ophthalmologist for cycloplegic refraction measurement (reference examination). The ophthalmologist was blinded to the referral conclusion and refraction measurements of the orthoptist. Results: A total of 300 patients (149 girls and 151 boys) were included. Examination by an orthoptist was unreliable/incomplete in 7% of cases. An abnormality was detected by the orthoptist in ≥1 of the screening tests among 42% of patients; these patients were thus considered as requiring referral to an ophthalmologist. Reference ophthalmological examination found 41% of patients required treatment. The diagnostic parameters of this screening protocol were 90% for sensitivity and 89% for specificity. Discussion: We validate the effectiveness and feasibility of the AFSOP screening protocol for detection of amblyopia and risk factors for amblyopia in 3-year-olds as well as the recommended criteria for referral to an ophthalmologist.ClinicalTrials.gov https://clinicaltrials.gov/ct2/show/NCT04395560.Number: NCT04395560.

Predicting myopic changes in children wearing glasses using the Plusoptix photoscreener

INTRODUCTION

With high increase in myopia prevalence, we aimed to assess whether Plusoptix_A09 can be used in myopic children over spectacles to predict visual acuity (VA) and myopic refraction changes.

METHODS

Myopic children underwent a complete ophthalmological examination. Plusoptix_A09 was performed over spectacles. VA changes, refraction changes and time since previous glasses prescription, were determined. Age, current or past history of amblyopia, presence of strabismus and self-perception of VA changes were registered.

RESULTS

In total, 199 patients were included. Spherical power (SP) and spherical equivalent (SE) measured by Plusoptix_A09 over spectacles predicted both VA changes (p < 0.001) and refraction changes (p < 0.001). Values of SP < - 0.06D or SE < - 0.22D indicated a VA decrease (AUC > 0.9, p < 0.01) for sensitivity and specificity of 85.1%, 82.1% and 82.6%, 83.3%, respectively. Age and ophthalmological comorbidities did not influence Plusoptix_A09 measurements (p > 0.05). Plusoptix_A09 over spectacles was a stronger predictor of VA changes when compared to children's self-perception, either in 4-9-year-old patients (p < 0.001 versus p = 0.628) and in 10-18-year-old children (OR <  = 0.066 versus OR = 0.190). A decrease in SP and SE of - 0.10D in Plusoptix_A09 predicted a myopia progression of - 0.04D and - 0.05D, respectively.

CONCLUSION/RELEVANCE

This study unveiled new features for the Plusoptix, a worldwide available photoscreener used in amblyopia screening. When Plusoptix is performed in children with their glasses on, it can rapidly predict myopia progression. For each decrease of - 0.10D in Plusoptix, a myopia progression of -0.05D is expected. Moreover, Plusoptix is more reliable than children's self-perception of visual acuity changes, making it a useful tool either in primary care or ophthalmology practice.

A population-level post-screening treatment cost framework to help inform vision screening choices for children under the age of seven

PURPOSE/BACKGROUND

Visual acuity (VA) screening in children primarily detects low VA and amblyopia between 3 and 6 years of age. Photoscreening is a low-cost, lower-expertise alternative which can be carried out on younger children and looks instead for refractive amblyopia risk factors so that early glasses may prevent or mitigate the conditions. The long-term benefits and costs of providing many children with glasses in an attempt to avoid development of amblyopia for some of them needs clarification. This paper presents a framework for modeling potential post-referral costs of different screening models once referred children reach specialist services.

METHODS

The EUSCREEN Screening Cost-Effectiveness Model was used together with published literature to estimate referral rates and case mix of referrals from different screening modalities (photoscreening and VA screening at 2, 3-4 years and 4-5 years). UK 2019-20 published National Health Service (NHS) costings were used across all scenarios to model the comparative post-referral costs to the point of discharge from specialist services. Potential costs were compared between a) orthoptist, b) state funded ophthalmologist and c) private ophthalmologist care.

RESULTS

Earlier VA screening and photoscreening yield higher numbers of referrals because of lower sensitivity and specificity for disease, and a different case mix, compared to later VA screening. Photoscreening referrals are a mixture of reduced VA caused by amblyopia and refractive error, and children with amblyopia risk factors, most of which are treated with glasses. Costs relate mainly to the secondary care providers and the number of visits per child. Treatment by an ophthalmologist of a referral at 2 years of age can be more than x10 more expensive than an orthoptist service receiving referrals at 5 years, but outcomes can still be good from referrals aged 5.

CONCLUSIONS

All children should be screened for amblyopia and low vision before the age of 6. Very early detection of amblyopia refractive risk factors may prevent or mitigate amblyopia for some affected children, but population-level outcomes from a single high-quality VA screening at 4-5 years can also be very good. Total patient-journey costs incurred by earlier detection and treatment are much higher than if screening is carried out later because younger children need more professional input before discharge, so early screening is less cost-effective in the long term. Population coverage, local healthcare models, local case-mix, public health awareness, training, data monitoring and audit are critical factors to consider when planning, evaluating, or changing any screening programme.

The UCI EyeMobile Preschool Vision Screening Program: Refractive Error and Amblyopia Results from the 2019-2020 School Year

Purpose

To introduce the University of California Irvine (UCI) EyeMobile for Children preschool vision screening program and describe the ophthalmic examination results of children who failed screening with the PlusoptiX S12C photoscreener during one school year.

Patients and Methods

Children aged 30-72 months were screened with the PlusoptiX using ROC mode 3 during the 2019-2020 school year. Children who failed screening were referred for comprehensive eye examination on the EyeMobile mobile clinic. Presence of amblyopia risk factors (ARFs), amblyopia, and refractive error was determined via retrospective review of records. Amblyopia was defined as unilateral if there was ≥ 2-line interocular difference in the best-corrected visual acuity (BCVA) and as bilateral if BCVA was < 20/50 for children < 4 years old and < 20/40 for children ≥ 4 years old. ARFs were defined using 2021 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) instrument-based screening guidelines.

Results

5226 children were screened during the study period. Of the 546 children who failed screening, 350 (64%) obtained consent and were examined. Mean age of examined children was 4.45 years. Amblyopia was found in 8% of examined children, with unilateral amblyopia seen in 79% of amblyopic subjects. Glasses were prescribed to 246 (70.3%) children. Of the 240 children who received cycloplegic examinations, 43% had hyperopia and 30% had myopia. The positive predictive value (PPV) of the PlusoptiX screening for ARFs in children who received cycloplegic examinations was 70.4%.

Conclusion

A significant proportion of Orange County preschoolers with refractive errors and amblyopia have unmet refractive correction needs. The PlusoptiX S12C photoscreener is an adequate screening device for the UCI EyeMobile for Children program, although modification of device referral criteria may lead to increased PPV. Further research is necessary to understand and overcome the barriers to childhood vision care in our community.

A Systematic Review of Current Teleophthalmology Services in New Zealand Compared to the Four Comparable Countries of the United Kingdom, Australia, United States of America (USA) and Canada

BACKGROUND

Over 700,000 New Zealanders (NZ), particularly elderly and Māori, live without timely access to specialist ophthalmology services. Teleophthalmology is a widely recognised tool that can assist in overcoming resource and distance barriers. Teleophthalmology gained unprecedented traction in NZ during the COVID-19 pandemic and subsequent lockdown. However, its provision is still limited and there are equity issues. The aim of this study was to conduct a systematic review identifying, describing and contrasting teleophthalmology services in NZ with the comparable countries of Australia, USA, Canada and the United Kingdom.

METHODS

The electronic databases Embase, PubMed, Web of Science, Google Scholar and Google were systemically searched using the keywords: telemedicine, ophthalmology, tele-ophthalmology/teleophthalmology. The searches were filtered to the countries above, with no time constraints. An integrative approach was used to synthesise findings.

RESULTS

One hundred and thirty-two studies were identified describing 90 discrete teleophthalmology services. Articles spanned from 1997 to 2020. Models were categorised into general eye care (n=21; 16%); emergency/trauma (n=6; 4.5%); school screening (n=25; 19%); artificial intelligence (AI) (n=23; 18%); and disease-specific models of care (MOC) (n=57; 43%). The most common diseases addressed were diabetic retinopathy (n=23; 17%); retinopathy of prematurity (n=9; 7%); and glaucoma (n=8; 6%). Programs were mainly centred in the US (n=72; 54.5%), followed by the UK (n=29; 22%), then Canada (n=16; 12%), Australia (n=13; 10%), with the fewest identified in NZ (n=3; 2%). Models generally involved an ophthalmologist consultative service, remote supervision and triaging. Most models involved local clinicians transmitting fed-forward or live images.

CONCLUSION

Teleophthalmology will likely play a crucial role in the future of eye care. COVID-19 has offered a unique opportunity to observe the use of teleophthalmology services globally. Feed-forward and, increasingly, live-based teleophthalmology services have demonstrated feasibility and cost-effectiveness in similar countries internationally. New Zealand's teleophthalmology services, however, are currently limited. Investing in strategic partnerships and technology at a national level can advance health equities in ophthalmic care.

Amblyopia risk factors among pediatric patients in a hospital-based setting using photoscreening

PURPOSE

The aim of our study was to determine the prevalence of amblyopia risk factors in children visiting the American University of Beirut Medical Center (AUBMC) using automated vision screening.

METHODS

This was a hospital-based screening of 1102 children aged between 2 and 6 years. Vision screening was performed using PlusoptiX S12 over 2 years (2018-2020). The need for referral to a pediatric ophthalmologist was based on the amblyopia risk factors set forth by the American Association for Pediatric Ophthalmology and Strabismus. Referred patients underwent a comprehensive eye examination.

RESULTS

A total of 1102 children were screened, 63 were referred for amblyopia risk factors (5.7%); 37/63 (59%) underwent comprehensive eye examination and 73% were prescribed glasses. Of the non-referred group of children, 6.35% had astigmatism, 6.25% were hyperopic and 3.27% were myopic. The refractive errors observed among the examined patients were distributed as follows: 41% astigmatism, 51% hyperopia, and 8% myopia; amblyopia was not detected. Refractive amblyopia risk factors were associated with the presence of systemic disorders. Bland-Altman plots showed most of the differences to be within limits of agreement.

CONCLUSION

Using an automated vision screener in a hospital-based cohort of children aged 2 to 6 years, the rate of refractive amblyopia risk factors was 5.7%. Hyperopia was the most commonly encountered refractive error and children with systemic disorders were at higher risk.

Evaluation of the PlusoptiX photoscreener in the examination of children with intellectual disabilities

PURPOSE:

This study aimed to determine whether the plusoptiX vision screener (PVS) can be used to detect amblyogenic risk factors (ARFs) as defined by the American Association for Paediatric Ophthalmology and Strabismus Vision Screening Committee guidelines (2013) for automated vision screening devices.

METHODS:

In this cross-sectional study, children attending a special needs school underwent screening with the PVS and complete ophthalmologic examinations. Ophthalmologic examinations were used as the gold standard to compute the prevalence, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and testability.

RESULTS:

Forty-four children with special needs (mean age, 8.5 years; range, 4–18 years) were included. The PVS recommended referral of 31 cases (referral rate 70%). Thirty-nine of the 44 children (89%) met the referral-positive threshold for strabismus, reduced vision and/or amblyogenic factors on examination. The plusoptiX had a sensitivity of 40% (confidence interval [CI] 7%–83%), specificity of 78% (CI 55%–85%), PPV of 15% (CI 3%–46%), and NPV of 90.3% (CI 73%–97%). The PVS underestimated refractive errors by 0.67 to 0.71 D in the right (P < 0.001) and left eyes (P = 0.002). Testability was relatively low, with the PVS at 75% compared to the gold standard examination at 100%.

CONCLUSION:

We found that although the plusoptiX photoscreener might be a useful tool in pediatric vision screening, it might not perform as well in children with intellectual disabilities. Utilization of the PVS as a single screening device may fail to identify a considerable proportion of young children with ARFs or amblyopia.

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.

Calibration of the PlusOptix PowerRef 3 with change in viewing distance, adult age and refractive error

Purpose

The PowerRef 3 is frequently used in studying the near triad of accommodation, vergence and pupil responses in normal and clinical populations. Within a range, the defocus measurement of the PowerRef 3 is linearly related to the eye's defocus. While the default factory‐calibrated slope of this relation (calibration factor) is 1, it has been shown that the slope can vary across individuals. Here, we addressed the impact of changes in viewing distance, age and defocus of the eye on the calibration factor.

Methods

We manipulated viewing distance (40 cm, 1 m and 6 m) and recruited participants with a range of accommodative capabilities: participants in their 20s, 40s and over 60 years old. To test whether any effect was larger than the range of measurement reliability of the instrument, we collected data for each condition four times: two in the same session, another on the same day, and one on a different day.

Results

The results demonstrated that viewing distance did not affect the calibration factor over the linear range, regardless of age or uncorrected refractive error. The largest proportion of the variance was explained by between‐subject differences.

Conclusions

Calibration data for the PowerRef 3 were not sensitive to changes in viewing distance. Nevertheless, our results re‐emphasise the relevance of calibration for studies of individual participants.

A Comparison of Three Different Photoscreeners in Children

PURPOSE

To compare the results obtained from three non-cycloplegic handheld photorefractometers with cycloplegic autorefractometry (Topcon KR-8100; Topcon Corporation, Tokyo, Japan) measurement in children.

METHODS

The refractive status of 238 eyes in 119 healthy children was assessed. The values acquired using photorefraction with the non-cycloplegic PlusoptiX A12 (Plusoptix GmbH, Nuremberg, Germany), Retinomax K-plus 3 (Righton, Tokyo, Japan), and Spot Vision Screener (Welch Allyn, Skaneateles Falls, NY) devices were compared with those obtained from the cycloplegic Topcon KR-8100. The agreement between the measurements was assessed using the intraclass correlation coefficient.

RESULTS

The mean age was 10.1 ± 3.2 years (range: 6 to 17 years). The mean spherical value for the right eyes was 0.38 diopters (D) (range: -4.50 to 6.25 D) for the Plusoptix A12; 0.45 D (range: -4.50 to 6.25 D) for the Spot Vision Screener; -1.15 D (range: -8.75 to 6.50 D) for the Retinomax K-plus 3; and 0.62 (range: -4.50 to 6.00) for the Topcon KR-8100. The mean spherical equivalent value for the right eyes was 0.41 D (range: -4.50 to 7.90 D) for the Plusoptix A12; 0.18 D (range: -4.75 to 6.13 D) for the Spot Vision Screener; -1.30 D (range: -10.50 to 6.38 D) for the Retinomax K-plus 3; and 0.67 D (range: -4.00 to 6.00 D) for the Topcon KR-8100 (for the right eyes).

CONCLUSIONS

The photorefractometer method was beneficial in the measurement of refractive errors of school-aged children. The PlusoptiX A12 photorefractometer method may eliminate the need for cycloplegia in the detection of refractive errors in children. [J Pediatr Ophthalmol Strabismus. 2018;55(5):306-311.].

Primary Care Implementation of Instrument-Based Vision Screening for Young Children

Vision screening for young children can detect conditions that may lead to amblyopia and vision loss if left untreated. Portable vision screening devices with high levels of precision are now available, but their effectiveness in busy primary care settings is unknown. We analyzed the effect of deploying instrument screening devices (SPOT Vision Screener, Welch-Allyn) in 19 pediatric practices. At baseline, using chart-based screening, 65.3% of 3- to 5-year-old children completed screening. A significant increase was observed starting 3 weeks after delivery of devices, and a stable level was reached 12 weeks after implementation, with 86.5% of children completing vision screening ( P = .007 by interrupted time series analysis). Improvement was greatest among 3-year-olds (44.0%-79.8%) but was also seen among 4-year-olds (70.9%-88.4%) and 5-year-olds (80.3%-90.8%). The deployment of vision screening devices in primary care practices substantially improved completed screening among preschool-aged children.

Critical Assessment of an Ocular Photoscreener

PURPOSE

To determine the accuracy of the PlusoptiX A12 photoscreener (PlusoptiX, Inc., Atlanta, GA) in detecting amblyopia or ambylogenic risk factors in pediatric patients in Nebraska.

METHODS

Using the PlusoptiX A12 photoscreener, data were collected from pediatric patients seen at a single pediatric ophthalmology practice. Each patient was screened using the device and also received a comprehensive ophthalmic examination. The results of the PlusoptiX A12 photoscreener were compared to the gold standard, comprehensive ophthalmic examination findings. The assessment of amblyopia or amblyogenic risk factors in the patients was based on the updated American Association for Pediatric Ophthalmology and Strabismus (AAPOS) referral criteria guidelines.

RESULTS

Data were collected from 219 consecutive pediatric patients (438 eyes) during the 3-month study period. Among the patients, 87 (40%) children were determined to have amblyopia or ambylogenic risk factors after the comprehensive pediatric ophthalmology examination based on the AAPOS guidelines. The PlusoptiX A12 photoscreener was found to have a sensitivity of 93.02%, specificity of 84.96%, false-positive rate of 9.13%, false-negative rate of 2.74%, positive predictive value of 80.00%, and negative predictive value of 94.96%.

CONCLUSIONS

The PlusoptiX A12 photoscreener is viable and comparable to various commercially available devices in the detection of refractive amblyogenic risk factors based on the Nebraska pediatric patient population. Future studies may show increased sensitivity by combining the use of the PlusoptiX A12 photoscreener with an alternate cover test. [J Pediatr Ophthalmol Strabismus. 2018;55(3):194-199.].

The PlusoptiX Photoscreener and the Retinomax Autorefractor as Community-based Screening Devices for Preschool Children

PURPOSE

To compare the performance of the PlusoptiX S12 mobile photoscreener and the Retinomax K+3 Autorefractor as screening devices in preschool children.

METHODS

Children ranging from 3 to 5 years of age from 11 San Diego County preschools underwent vision screening in their schools where ambient light could not always be controlled using both the Retinomax and the PlusoptiX. Cycloplegic refraction on the consented children was subsequently performed on the UCSD EyeMobile for children on-site at the school locations.

RESULTS

A total of 321 children were screened with the PlusoptiX and Retinomax. The PlusoptiX referred 22% of children, of whom 70% of the referrals were read as "unable". The Retinomax referred 13% and there were no "unables". Similar results occurred in the cycloplegic-refracted 182 consented children-64% of the PlusoptiX referrals were read as "unable" . Only one third of these "unables" required glasses. Both devices referred the four children with amblyopia and one case of strabismus. However, PlusoptiX's 3 false negatives had amblyopia risk factors (ARFs) while the one Retinomax's false negative did not have ARFs. The Retinomax screening had 95% sensitivity and 94% specificity. The PlusoptiX screening had 86% sensitivity and 84% specificity.

CONCLUSION

In this preschool population and environment, the PlusoptiX referred 63% more than the Retinomax in addition to a lower specificity and sensitivity. Adjusting PlusoptiX referral criteria might not substantially improve the specificity of the PlusoptiX due to the high numbers of "unables".

Tests for detecting strabismus in children aged 1 to 6 years in the community

BACKGROUND

Strabismus (misalignment of the eyes) is a risk factor for impaired visual development both of visual acuity and of stereopsis. Detection of strabismus in the community by non-expert examiners may be performed using a number of different index tests that include direct measures of misalignment (corneal or fundus reflex tests), or indirect measures such as stereopsis and visual acuity. The reference test to detect strabismus by trained professionals is the cover‒uncover test.

OBJECTIVES

To assess and compare the accuracy of tests, alone or in combination, for detection of strabismus in children aged 1 to 6 years, in a community setting by non-expert screeners or primary care professionals to inform healthcare commissioners setting up childhood screening programmes.Secondary objectives were to investigate sources of heterogeneity of diagnostic accuracy.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 12) (which contains the Cochrane Eyes and Vision Trials Register) in the Cochrane Library, the Health Technology Assessment Database (HTAD) in the Cochrane Library (2016, Issue 4), MEDLINE Ovid (1946 to 5 January 2017), Embase Ovid (1947 to 5 January 2017), CINAHL (January 1937 to 5 January 2017), Web of Science Conference Proceedings Citation Index-Science (CPCI-S) (January 1990 to 5 January 2017), BIOSIS Previews (January 1969 to 5 January 2017), MEDION (to 18 August 2014), the Aggressive Research Intelligence Facility database (ARIF) (to 5 January 2017), the ISRCTN registry (www.isrctn.com/editAdvancedSearch); searched 5 January 2017, ClinicalTrials.gov (www.clinicaltrials.gov); searched 5 January 2017 and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en); searched 5 January 2017. We did not use any date or language restrictions in the electronic searches for trials. In addition, orthoptic journals and conference proceedings without electronic listings were searched.

SELECTION CRITERIA

All prospective or retrospective population-based test accuracy studies of consecutive participants were included. Studies compared a single or combination of index tests with the reference test. Only those studies with sufficient data for analysis were included specifically to calculate sensitivity and specificity and determine diagnostic accuracy.Participants were aged 1 to 6 years. Studies reporting participants outside this range were included if subgroup data were available.Permitted settings included population-based vision screening programmes or opportunistic screening programmes, such as those performed in schools.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. In brief, two review authors independently assessed titles and abstracts for eligibility and extracted the data, with a third senior author resolving any disagreement. We analysed data primarily for specificity and sensitivity.

MAIN RESULTS

One study from a total of 1236 papers, abstracts and trials was eligible for inclusion with a total number of participants of 335 of which 271 completed both the screening test and the gold standard test. The screening test using an automated photoscreener had a sensitivity of 0.46 (95% confidence interval (CI) 0.19 to 0.75) and specificity of 0.97 (CI 0.94 to 0.99). The overall number affected by strabismus was low at 13 (4.8%).

AUTHORS' CONCLUSIONS

There is very limited data in the literature to ascertain the accuracy of tests for detecting strabismus in the community as performed by non-expert screeners. A large prospective study to compare methods would be required to determine which tests have the greatest accuracy.

Pediatric vision screening using the plusoptiX A12C photoscreener in Chinese preschool children aged 3 to 4 years

This study evaluated the performance of plusoptiX A12C in detecting amblyopia risk factors (ARFs) in Chinese children aged 3-to-4-year. PlusoptiX examination was successfully conducted among 1,766 subjects without cycloplegia to detect refractive error, asymmetry and media opacity. Cycloplegic retinoscopy (CR) was conducted on 357 children suspected of having vision abnormalities. Statistical differences between CR and the device were confirmed using the mean spherical value (+1.41 ± 0.87 D versus +1.14 ± 0.81 D), cylindrical value (−0.47 ± 0.64 versus −0.84 ± 0.78) and spherical equivalent (SE) value (+1.17 ± 0.84 D versus +0.72 ± 0.64 D) (all P < 0.0001). In the emmetropia group, the differences were statistically significant for the cylinder and SE (all P < 0.0001) but not the sphere (P = 0.33). In the hyperopia group, the differences were statistically significant for the sphere, cylinder and SE (all P < 0.0001). For refractive and strabismic ARFs detection, the sensitivity, specificity, positive predictive value, and negative predictive value were calculated, respectively.

A comparison of plusoptiX A12 measurements with cycloplegic refraction

PURPOSE

To test the accuracy and reliability of the plusoptiX A12 in detecting amblyogenic risk factors.

METHODS

We prospectively collected data on children undergoing screening with the plusoptiX A12, cycloplegic refraction, and complete ophthalmic examination. American Association for Pediatric Ophthalmology and Strabismus (AAPOS) 2013 guidelines for the detection of amblyogenic risk factors were used for plusoptiX A12 screening and comparison of the results of both examination modes.

RESULTS

Data on 402 eyes of 201 children (mean age, 7.63 ± 3.41 years) was collected. Mean (with standard deviation) cycloplegic refraction results were as follows: sphere, 0.88 ± 1.5 D; cylinder, -0.61 ± 0.74 D; axis, 71.17 ± 71.04; and spherical equivalent, 0.68 ± 2.63. The plusoptiX A12 measurements were as follows: sphere, 0.58 ± 1.4 D; cylinder, -0.66 ± 0.77 D; axis, 77.3 ± 68.9; and spherical equivalent, 0.25 ± 1.3. We found a strong correlation (Pearson) for sphere (r = 0.91), cylinder (r = 0.81), and axis (r = 0.7). The mean difference of the myopic spherical component between the plusoptiX and cycloplegic refraction was -0.048 ± 0.55 (95% LoA, +1.04 to -1.14 D); for the hyperopic spherical component, 0.37 ± 0.93 (LoA, +2.20 to -1.45 D); and for the cylindrical component, 0.05 ± 0.32 (LoA, +0.68 to -0.57D). The sensitivity, specificity, positive and negative predictive values for myopia were, respectively, 86%, 93%, 82%, and 94%; for astigmatism, 85%, 98%, 88% and 98%; and for hyperopia, 40%, 100%, 100%, and 98%.

CONCLUSIONS

The plusoptiX A12 accuracy is high in all subgroups but better in the myopic, astigmatic, and anisometropic subgroups. Reliability was lower in the hyperopic eyes, possibly resulting in underestimation of hyperopic refractive error.

Accuracy of PlusOptix A09 distance refraction in pediatric myopia and hyperopia

Background

The PlusOptix photoscreeners (PlusOptix GmbH, Nuremberg, Germany) is used in many vision screening programs. The purpose of the present study was to further explore the accuracy of the PlusOptix A09 photoscreener in children with ametropia (myopia or hyperopia).

Methods

A total of 70 eyes (35 children) were prospectively included. Before administration with the cycloplegia treatment 1 % cyclopentolate hydrochloride, children underwent refraction measurement with the PlusOptix A09. A refraction was then performed after cycloplegia with either Retinomax hand-held or Nidek autorefractor before and after 3 years old, respectively.

Results

The median (interquartile range) age was 58 (18 to 86) months. The mean (SD) spherical equivalent differed between PlusOptix A09 and cycloplegic autorefraction (+0.54 [1.82] D vs +1.06 [2.04] D, p = 0.04). PlusOptix A09 refraction was positively correlated with cycloplegic autorefraction (r = 0.81, p < 0.001) with higher coefficient in myopic than in hyperopic children (r = 0.91, p = 0.0002 and r = 0.52, p = 0.01, respectively). The mean (SD) difference between PlusOptix A09 and cycloplegic autorefraction was higher with hyperopia than myopia (0.73 [1.34] vs 0.05 [0.66], p = 0.01). The proportion of children with < 1-D difference between cycloplegic and PlusOptix A09 refraction was 68.8 %, higher with myopia than hyperopia (90 % vs 54.5 %, p = 0.01).

Conclusion

The spherical equivalent value with non-cycloplegic PlusOptix A09 refraction is closer to that with cycloplegic autorefraction than non-cycloplegic autorefraction. The PlusOptix A09 photoscreener underestimated the hyperopia of 0.73 D and slightly overestimated myopia of 0.05 D. The PlusOptix A09 could be used for screening with higher accuracy in myopic than hyperopic children.

Field Evaluation of Automated Vision Screening Instruments: Impact of Referral Criteria Choice on Screening Outcome

PURPOSE

Automated vision screeners can identify children with amblyopia risk factors. Two screening instruments having different referral criteria were evaluated in a community setting: SPOT (Pediavision, Lake Mary, FL) (sensitive manufacturer's referral criteria) and plusoptiX S08 (Plusoptix GmbH, Nuremberg, Germany) (specific modified Arthur referral criteria).

METHODS

All children were screened by SPOT, and referred children were then screened using plusoptiX. Referred children received a gold standard examination to determine whether amblyopia risk factors were present.

RESULTS

A total of 2,801 treatment-naïve children were screened using SPOT. Of these, 307 (11.0%) were referred by SPOT and subsequently screened by plusoptiX; 100 received a gold standard examination. Amblyopia risk factors were present in 43% (43 of 100) referred by SPOT compared to 72.7% (32 of 44) for plusoptiX. Eleven of 56 referred by SPOT had amblyopia risk factors that would have been missed by plusoptiX, including three with mild amblyopia.

CONCLUSIONS

PlusoptiX with modified Arthur referral criteria can be a highly specific screening device detecting amblyopia risk factors without missing children with moderate/severe amblyopia.

Performance of the Plusoptix A09 photoscreener in detecting amblyopia risk factors in Chinese children attending an eye clinic

Purpose

To assess the accuracy of the Plusoptix A09 photoscreener in detecting amblyopia risk factors in children and determine referral criteria when using Plusoptix A09 for a large-scale vision screening.

Methods

Pediatric patients attending our eye clinic underwent a comprehensive ophthalmic examination that included photorefraction, orthoptic examination, anterior segment assessment, fundus examination and cycloplegic retinoscopy. The measurements were collected for statistical analyses.

Results

One hundred and seventy-eight children (mean age ± SD: 6.2±2.4 years, range: 2.2 to 14.1 years) were included in the study. The mean spherical equivalent (SE) obtained using Plusoptix A09 (P_SE) was 0.57 D lower than that obtained from cycloplegic retinoscopy (CR_SE) (P = 0.00). However, there was no statistically significant difference of Jackson cross cylinder J₀ and J₄₅ between Plusoptix A09 (P_J) and cycloplegic retinoscopy (CR_J) (P = 0.14, P = 0.26). The relationship of SE obtained from Plusoptix A09 and SE obtained from cycloplegic retinoscopy was presented as the equation: CR_SE = 0.358 + 0.776 P_SE + 0.064 P_SE² + 0.011 P_SE³. Based on the Receiver Operating Characteristic (ROC) curve, the Plusoptix A09 had an overall sensitivity of 94.9% and specificity of 67.5% for detecting refractive amblyopia risk factors. The sensitivity and specificity of the Plusoptix A09 for detection of strabismus were 40.7% and 98.3%, respectively; detection of amblyopia and/or strabismus was 84.7% and 63.2%, respectively.

Conclusions

The Plusoptix A09 photoscreener underestimated hyperopia and overestimated myopia according to SE when compared with cycloplegic retinoscopy. The accuracy of the Plusoptix A09 in detecting amblyopia risk factors in children could be improved by the regression equation and optimized criteria for refractive amblyopia risk factors developed in the present study. Moreover, the Plusoptix A09 photoscreener is not suitable for a large-scale strabismus screening when it is applied solely.

Objective vision screening in 3-year-old children at a multispecialty practice

BACKGROUND

Vision screening is rarely effectively accomplished for 3-year-olds as part of pediatric well-child examinations. We investigate changes in screening rates and positive predictive values of referrals for 3-year-olds after introducing a photoscreener to a multispecialty group practice.

METHODS

The vision screening results of 3-year-old children undergoing routine well-child examinations between 2007 and 2013 were retrospectively reviewed. From 2007 to 2009, the only method available for vision screening was the Kindergarten Eye Test Chart. From 2010 to 2013 a PlusOptix photoscreener was also available. Rates of vision screening before and after PlusOptix adoption were compared. All children who failed screening were referred to a single pediatric ophthalmologist. Referral rates, follow-up rates, and positive predictive values were determined for PlusOptix photoscreening. Cases were defined by cycloplegic retinoscopy using the 2013 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) vision screening recommendations for amblyopia risk factors.

RESULTS

Of 593 children seen for their 3-year well-child examination between 2007-2009, before introduction of a photoscreener, 59 (10%) received vision screening. The screening rate increased to 766 of 958 (80%) between 2010 and 2013, after introduction of the PlusOptix (P < 0.001). Only 49% of children had a reliable first screening with PlusOptix, and the average number of screenings to obtain a reliable result was 2.39. The positive predictive value of PlusOptix referrals was 51% for amblyopia risk factors and 41% for potential amblyopia.

CONCLUSIONS

Availability of a photoscreener can increase the rate of vision screening for 3-year-old children in a multispecialty practice.

Photorefraction estimates of refractive power varies with the ethnic origin of human eyes

Eccentric infrared photorefraction is an attractive tool for measuring refractive errors of young children and uncooperative subjects, for it allows quick and non-invasive acquisition of data from both eyes simultaneously over a reasonably large dioptric range. Accuracy of refraction in this technique depends on calibration of luminance slope formed across the pupil into diopters (defocus calibration factor). Commercial photorefractors, like the PowerRef 3™ used in this study, employ an universal defocus calibration factor from one population (Caucasian) to convert raw data of all populations. This study reports significantly larger defocus calibration factors of PowerRef 3™ in 132 East Asian, African and Indian eyes, relative to the machine's default calibration (p < 0.001). The calibration slope of 50 Indian eyes was over-estimated by 64 ± 11% (mean ± 95%CI), vis-à-vis, retinoscopy (p < 0.001). The error reduced to ~6–7% upon rescaling the data using a calibration factor specific for Indian eyes or to that individual (p > 0.9, relative to no over-estimation). Our results therefore strongly suggest the use of an ethnicity- or individual-specific defocus calibration factor for accurate estimation of refraction using photorefraction. Inaccurate refraction estimates due to calibration errors will otherwise severely undermine the advantages of this technique.

Vision screening for children 36 to <72 months: recommended practices

PURPOSE

This article provides recommendations for screening children aged 36 to younger than 72 months for eye and visual system disorders. The recommendations were developed by the National Expert Panel to the National Center for Children's Vision and Eye Health, sponsored by Prevent Blindness, and funded by the Maternal and Child Health Bureau of the Health Resources and Services Administration, United States Department of Health and Human Services. The recommendations describe both best and acceptable practice standards. Targeted vision disorders for screening are primarily amblyopia, strabismus, significant refractive error, and associated risk factors. The recommended screening tests are intended for use by lay screeners, nurses, and other personnel who screen children in educational, community, public health, or primary health care settings. Characteristics of children who should be examined by an optometrist or ophthalmologist rather than undergo vision screening are also described.

RESULTS

There are two current best practice vision screening methods for children aged 36 to younger than 72 months: (1) monocular visual acuity testing using single HOTV letters or LEA Symbols surrounded by crowding bars at a 5-ft (1.5 m) test distance, with the child responding by either matching or naming, or (2) instrument-based testing using the Retinomax autorefractor or the SureSight Vision Screener with the Vision in Preschoolers Study data software installed (version 2.24 or 2.25 set to minus cylinder form). Using the Plusoptix Photoscreener is acceptable practice, as is adding stereoacuity testing using the PASS (Preschool Assessment of Stereopsis with a Smile) stereotest as a supplemental procedure to visual acuity testing or autorefraction.

CONCLUSIONS

The National Expert Panel recommends that children aged 36 to younger than 72 months be screened annually (best practice) or at least once (accepted minimum standard) using one of the best practice approaches. Technological updates will be maintained at http://nationalcenter.preventblindness.org.

Photoscreeners in the pediatric eye office: compared testability and refractions on high-risk children

PURPOSE

To compare refractive data and testability of Spot (PediaVision) and Plusoptix A09 (Plusoptix, Inc) photoscreeners and to compare each device with traditional cycloplegic retinoscopy.

DESIGN

Prospective, interventional case series.

METHODS

After informed consent, patients underwent testing with the Spot and Plusoptix photoscreeners before their examination by a pediatric ophthalmologist masked to the results. Data including testability and estimated refractions were entered into a Research Electronic Data Capture database for statistical analysis.

RESULTS

A total of 265 children were enrolled (mean age, 6.0 ± 3.4 years). Both devices produced a computer printout result in 250 (94.3%) of the patients. The Spot photoscreener provided a refractive estimate in all computer printouts, whereas the Plusoptix, used binocularly, provided a refractive estimate in 75.2% (188/250) of the printouts. Compared with cycloplegic retinoscopy, both devices underestimated hyperopia or overestimated myopia (-1.35 diopters [D] and -0.64 D, Spot and Plusoptix, respectively) and overestimated astigmatism (0.36 D and 0.32 D, Spot and Plusoptix, respectively). The intraclass correlation coefficient for spherical equivalents indicated good agreement between cycloplegic retinoscopy and Spot (0.806) and excellent agreement between cycloplegic retinoscopy and Plusoptix (0.898).

CONCLUSIONS

The Spot photoscreener provided refractive data on a greater percentage of children. The photorefractors correlated with cycloplegic retinoscopy refractive findings for sphere and spherical equivalents, but underestimated hyperopia or overestimated myopia and overestimated astigmatism. The binocular refractions of Plusoptix agreed more closely with the refractions of our pediatric ophthalmologists.

Photoscreeners in the pediatric eye office: compared testability and refractions on high-risk children

PURPOSE

To compare refractive data and testability of Spot (PediaVision) and Plusoptix A09 (Plusoptix, Inc) photoscreeners and to compare each device with traditional cycloplegic retinoscopy.

DESIGN

Prospective, interventional case series.

METHODS

After informed consent, patients underwent testing with the Spot and Plusoptix photoscreeners before their examination by a pediatric ophthalmologist masked to the results. Data including testability and estimated refractions were entered into a Research Electronic Data Capture database for statistical analysis.

RESULTS

A total of 265 children were enrolled (mean age, 6.0 ± 3.4 years). Both devices produced a computer printout result in 250 (94.3%) of the patients. The Spot photoscreener provided a refractive estimate in all computer printouts, whereas the Plusoptix, used binocularly, provided a refractive estimate in 75.2% (188/250) of the printouts. Compared with cycloplegic retinoscopy, both devices underestimated hyperopia or overestimated myopia (-1.35 diopters [D] and -0.64 D, Spot and Plusoptix, respectively) and overestimated astigmatism (0.36 D and 0.32 D, Spot and Plusoptix, respectively). The intraclass correlation coefficient for spherical equivalents indicated good agreement between cycloplegic retinoscopy and Spot (0.806) and excellent agreement between cycloplegic retinoscopy and Plusoptix (0.898).

CONCLUSIONS

The Spot photoscreener provided refractive data on a greater percentage of children. The photorefractors correlated with cycloplegic retinoscopy refractive findings for sphere and spherical equivalents, but underestimated hyperopia or overestimated myopia and overestimated astigmatism. The binocular refractions of Plusoptix agreed more closely with the refractions of our pediatric ophthalmologists.

Comparison of the Retinomax hand-held autorefractor versus table-top autorefractor and retinoscopy

AIM

To compare noncycloplegic and cycloplegic results of Retinomax measurements with findings achieved after cycloplegia using table-top autorefractor and retinoscopy.

METHODS

The study included 127 patients (mean age 96.7mo, range 21 to 221). Retinomax (Rmax) (Nikon Inc., Japan) was used to obtain noncycloplegic refraction. Under cycloplegia, refraction was measured with Rmax, table-top autorefractor (TTR) (Nikon NRK 8000, Inc., Japan) and retinoscopy. The values of sphere, spherical equivalent, cylinder and axis of cylinder were recorded for Rmax, TTR and retinoscopy in each eye. All results were analyzed statistically.

RESULTS

THE MEAN SPHERIC VALUES (SV), SPHERICAL EQUIVALENT VALUES (SEV) AND CYLINDRICAL VALUES (CV) OF THE NONCYCLOPLEGIC RMAX (SV: 0.64 D, SEV: 0.65 D and CV: 0.03 D, respectively) were found to be significantly lower than cycloplegic TTR (1.43 D, 1.38 D and 0.3 D; P=0.012, P=0.011 and P=0.04, respectively) and retinoscopy (1.34 D, 1.45 D and 0.23 D; P=0.04, P=0.002 and P=0.045, respectively). Mean cycloplegic SV, SEV, CV were not significantly different between Rmax and TTR, Rmax and retinoscopy, TTR and retinoscopy. Cycloplegic or noncycloplegic axis values were not different between any method.

CONCLUSION

Rmax may be used successfully as a screening tool but may not be accurate enough for actual spectacle prescription. Cycloplegic Rmax measurements may be able to identify refractive error in children because of approximate results to retinoscopy.

Preschool vision screening: update on guidelines and techniques

PURPOSE OF REVIEW

To discuss the current preschool vision screening (PVS) guidelines and review some of the newest vision screening techniques. The different vision screening practices and barriers to screening are discussed.

RECENT FINDINGS

Vision screening guidelines, which have been developed in response to the advances in technology and increased understanding of the developing visual system, have been recently updated by some of the major medical organizations that endorse vision screening. With advances in vision screening technology, there is a growing trend for screening at younger ages.

SUMMARY

PVS has been widely endorsed by various medical organizations as an effective way to detect preventable and treatable vision problems of childhood. Although PVS is widely recommended, actual screening rates remain low. There are several real and perceived barriers to screening which often prevents successful screening programs. Current vision screening guidelines take into account the recent advances in technology. With the development of new devices, vision screening can effectively be performed at younger ages.

The accuracy of the plusoptiX A08 photoscreener in detecting risk factors for amblyopia in central Iowa

PURPOSE

To evaluate the accuracy of the plusoptiX A08 photoscreener in detecting risk factors for amblyopia in children aged 0-5 years in central Iowa.

METHODS

The medical records of consecutive patients seen at 1 practice during a 2-month period were retrospectively reviewed. All patients were screened with the plusoptiX A08 photoscreener and received a comprehensive pediatric ophthalmology examination. Photoscreening results, according to our age-based criteria, were compared with the comprehensive examination findings. Patients were considered to have amblyopia or amblyogenic risk factors in the comprehensive examination based on the American Association for Pediatric Ophthalmology and Strabismus referral criteria guidelines.

RESULTS

A total of 290 children were examined during the study period. Of these, 190 (66%) patients were found to have amblyopia or amblyogenic risk factors during the pediatric ophthalmology examination on the basis of American Association for Pediatric Ophthalmology and Strabismus guidelines. The plusoptiX A08 offered an overall testability rate of 98%, sensitivity of 87%, specificity of 88%, positive predictive value of 93%, and negative predictive value of 78%. The sensitivity for detection of strabismus ≤20(Δ) was 52%.

CONCLUSIONS

The plusoptiX showed a high sensitivity for the detection of refractive amblyogenic risk factors and had a high successful testability rate in infants; however, it had low sensitivity for detecting strabismus ≤20(Δ). We postulate that sensitivity for detecting amblyogenic risk factors can be improved by combining the use of this instrument with a cover or stereo test.

A comparison of the Plusoptix S08 photorefractor to retinoscopy and cycloretinoscopy

BACKGROUND

The aim was to compare outcome measures of refractive error by the Plusoptix S08 photorefractor with measures obtained by retinoscopy and cycloretinoscopy in children.

METHOD

The refractive error of the right eye of 144 non-strabismic children, aged 2.5 to 5.5 years, was determined by Plusoptix S08 photorefraction, retinoscopy and cycloretinoscopy. Agreement between outcome measures of refractive error (spherical error, cylindrical error and spherical equivalent) by the three techniques were tested by Bland-Altman limits of agreement.

RESULTS

The mean difference for spherical equivalent results of photorefraction (P(se)) minus those of retinoscopy (R(se)) and photorefraction minus those of cycloretinoscopy (CR(se)) were +0.53 ± 0.62 D and -0.22 ± 0.75 D, respectively. The 95 per cent limits of agreement for spherical photorefraction with retinoscopy and cycloretinoscopy were ±1.22 D (range -0.69 to +1.75) and ±1.47 D (range -1.69 to +1.25), respectively. The mean difference for cylindrical results of photorefraction (P(c)) minus those of retinoscopy (R(c)) and Pc minus those of cycloretinoscopy (CR(c)) were +0.11 ± 0.39 D and +0.13 ± 0.44 D, respectively. The 95 per cent limits of agreement for P(c) with R(c) and CR(c) were ±0.76 D (range -0.65 to +0.87) and ±0.86 D (range -0.73 to +0.99), respectively. The mean and standard deviation of weighted axes difference, comparing Plusoptix S08 and retinoscopy was 0.25 ± 0.36 and comparing Plusoptix S08 and cycloretinoscopy was 0.29 ± 0.51. Eighty-two per cent of the spherical equivalent findings in photorefraction and cycloretinoscopy show a difference of within 1.00 D. Regarding cylindrical power, this percentage is 96.6 per cent.

CONCLUSION

As the findings demonstrate a fairly good consistency between the results of the Plusoptix S08 Photorefractor without using cycloplegic agents and those of cycloretinoscopy, the Plusoptix S08 is a fairly accurate tool to estimate refractive errors of children in the limited working range of the instrument.

A comparison of different autorefractors with retinoscopy in children

PURPOSE

To compare the results of different refractive error measurement devices including table-mounted and hand-held autorefractors and videoretinoscopy with cycloplegic retinoscopy (CR) in children to evaluate the usability and reliability of these devices in measuring refractive errors.

METHODS

Two hundred eyes of 100 children underwent autorefraction using table-mounted autorefractor with and without cycloplegia and videoretinoscopy after cycloplegia. All results were compared statistically.

RESULTS

The mean spheric values (SV) and spherical equivalent values (SEV) of the non-cycloplegic table-mounted autorefractor were found to be significantly lower and those of the cycloplegic table-mounted autorefractor were found to be significantly higher than CR results. There was no statistically significant difference in terms of mean SV and SEV between the hand-held autorefractor and CR. Although the mean SV using videoretinoscopy were 0.15 diopters lower than CR, this difference was not significant. Comparing CR with the other refraction methods, all devices correlated with each other. Sensitivity in diagnosing myopia was low for all methods but sensitivity in diagnosing hyperopia and astigmatism was high for table-mounted and hand-held autorefractors. The other reliability parameters were found to be similar for all devices.

CONCLUSIONS

Both videoretinoscopy and hand-held autorefractor can be used in both screening and examination for children as an alternative to CR and table-mounted autorefractor.

Modification of Plusoptix referral criteria to enhance sensitivity and specificity during pediatric vision screening

PURPOSE

To determine the impact of using several different proposed sets of referral criteria on the specificity and sensitivity of the plusoptiX S08 photoscreener for detecting amblyopia risk factors.

METHODS

During a 2-month period, 144 children ages 9 months to 14 years were screened at the Tennessee Lions Eye Center before receiving a comprehensive eye examination and cycloplegic refraction. Three previously published sets of referral criteria were used for screening, including the manufacturer's criteria and the criteria proposed by Arthur and colleagues, which are nearly identical to the gold standard examination failure thresholds proposed by the Vision Screening Committee of the American Association of Pediatric Ophthalmology and Strabismus (AAPOS). Modifications of these criteria also were evaluated. The screening results obtained by the plusoptiX S08 were compared with the results from the gold standard pediatric ophthalmologic examination, and the respective sensitivities and specificities of each set of referral criteria in detecting amblyopia risk factors identified by the AAPOS Vision Screening Committee were calculated.

RESULTS

The manufacturer's criteria yielded high sensitivity (100%) but very low specificity (37%). The Arthur criteria, which used the values for the AAPOS-defined amblyopia risk factors as referral criteria, maintained sensitivity (89%) and greatly improved specificity (76%). Two modifications of the Arthur criteria further increased specificity with minimal loss of sensitivity.

CONCLUSIONS

The manufacturer's criteria have excellent sensitivity but low specificity, warranting modification; other criteria increase specificity with minimal effect on sensitivity.

Screening for visual impairment in children ages 1-5 years: update for the USPSTF

CONTEXT

Screening could identify preschool-aged children with vision problems at a critical period of visual development and lead to treatments that could improve vision.

OBJECTIVE

To determine the effectiveness of screening preschool-aged children for impaired visual acuity on health outcomes.

METHODS

We searched Medline from 1950 to July 2009 and the Cochrane Library through the third quarter of 2009, reviewed reference lists, and consulted experts. We selected randomized trials and controlled observational studies on preschool vision screening and treatments, and studies of diagnostic accuracy of screening tests. One investigator abstracted relevant data, and a second investigator checked data abstraction and quality assessments.

RESULTS

Direct evidence on the effectiveness of preschool vision screening for improving visual acuity or other clinical outcomes remains limited and does not adequately address whether screening is more effective than no screening. Regarding indirect evidence, a number of screening tests have utility for identification of preschool-aged children with vision problems. Diagnostic accuracy did not clearly differ for children stratified according to age, although testability rates were generally lower in children 1 to 3 years of age. Treatments for amblyopia or unilateral refractive error were associated with mild improvements in visual acuity compared with no treatment. No study has evaluated school performance or other functional outcomes.

CONCLUSIONS

Although treatments for amblyopia or unilateral refractive error can improve vision in preschool-aged children and screening tests have utility for identifying vision problems, additional studies are needed to better understand the effects of screening compared with no screening.

Screening for refractive errors in children: the plusoptiX S08 and the Retinomax K-plus2 performed by a lay screener compared to cycloplegic retinoscopy

PURPOSE

To evaluate the performance of the autorefractor Retinomax K-plus2 and the photoscreener plusoptiX S08 in measuring refractive errors by comparing them with cycloplegic retinoscopy (CR) and to assess limitations associated with their use.

METHODS

Cross-sectional study to compare data from CR, performed by an orthoptist, to data from Retinomax K-plus2 and plusoptiX S08 performed by a lay screener. Sensitivity and specificity for the detection of significant refractive errors were determined according to American Academy of Pediatric Ophthalmology and Strabismus criteria.

RESULTS

Two hundred children were included, with a mean age of 5.2 ± 2.6 years (3 months to 11 years). Compared to CR, the plusoptiX S08 showed a mean difference of -1.13 ± 1.25 D (95% limits of agreement [LOA], -3.59 to +1.32) for spherical equivalent (SE) and -0.23 ± 0.53 D (LOA, -1.28 to +0.81) for the cylinder. Mean difference for the Retinomax K-plus2 before cycloplegia was -0.08 ± 0.58 D (LOA, -1.23 to +1.06) for SE and 0.03 ± 0.38 D (LOA, -0.72 to +0.78) for the cylinder; after cycloplegia -2.11 ± 1.64 D (LOA, -5.33 to +1.10) for SE and -0.06 ± 0.47 D (LOA, -0.98 to +0.86) for the cylinder. Sensitivity for detecting hyperopia >3.5 D with the plusoptiX S08 was 33.3%, the Retinomax before cycloplegia 31.0% and after cycloplegia 84.6% and high for detecting myopia, astigmatism, and anisometropia.

CONCLUSIONS

Retinomax K-plus2 and plusoptiX S08 have high sensitivity for the detection of myopia, astigmatism, and anisometropia compared to cycloplegic retinoscopy; however, when used without cycloplegia, hyperopia is underestimated.

Receding and disparity cues aid relaxation of accommodation

PURPOSE

Accommodation can mask hyperopia and reduce the accuracy of non-cycloplegic refraction. It is, therefore, important to minimize accommodation to obtain a measure of hyperopia as accurate as possible. To characterize the parameters required to measure the maximally hyperopic error using photorefraction, we used different target types and distances to determine which target was most likely to maximally relax accommodation and thus more accurately detect hyperopia in an individual.

METHODS

A PlusoptiX SO4 infra-red photorefractor was mounted in a remote haploscope which presented the targets. All participants were tested with targets at four fixation distances between 0.3 and 2 m containing all combinations of blur, disparity, and proximity/looming cues. Thirty-eight infants (6 to 44 weeks) were studied longitudinally, and 104 children [4 to 15 years (mean 6.4)] and 85 adults, with a range of refractive errors and binocular vision status, were tested once. Cycloplegic refraction data were available for a sub-set of 59 participants spread across the age range.

RESULTS

The maximally hyperopic refraction (MHR) found at any time in the session was most frequently found when fixating the most distant targets and those containing disparity and dynamic proximity/looming cues. Presence or absence of blur was less significant, and targets in which only single cues to depth were present were also less likely to produce MHR. MHR correlated closely with cycloplegic refraction (r = 0.93, mean difference 0.07 D, p = n.s., 95% confidence interval +/-<0.25 D) after correction by a calibration factor.

CONCLUSIONS

Maximum relaxation of accommodation occurred for binocular targets receding into the distance. Proximal and disparity cues aid relaxation of accommodation to a greater extent than blur, and thus non-cycloplegic refraction targets should incorporate these cues. This is especially important in screening contexts with a brief opportunity to test for significant hyperopia. MHR in our laboratory was found to be a reliable estimation of cycloplegic refraction.