Performance of Spot Photoscreener in Detecting Amblyopia Risk Factors in Chinese Pre-school and School Age Children Attending an Eye Clinic

Retinoscopes: Past and present

BACKGROUND

Retinoscopy is arguably the most important method in the eye clinic for diagnosing and managing refractive errors. Advantages of retinoscopy include its non-invasive nature, ability to assess patients of all ages, and usefulness in patients with limited cooperation or communication skills.

AIM

To discuss the history of retinoscopes and examine current literature on the subject.

METHODS

A search was conducted on the PubMed and with the reference citation analysis (https://www.referencecitationanalysis.com) database using the term "Retinoscopy," with a range restricted to the last 10 years (2013-2023). The search string algorithm was: "Retinoscopy" (MeSH Terms) OR "Retinoscopy" (All Fields) OR "Retinoscopes" (All Fields) AND [(All Fields) AND 2013: 2023 (pdat)].

RESULTS

This systematic review included a total of 286 records. Publications reviewed iterations of the retinoscope into autorefractors, infrared photo retinoscope, television retinoscopy, and the Wifi enabled digital retinoscope.

CONCLUSION

The retinoscope has evolved significantly since its discovery, with a significant improvement in its diagnostic capabilities. While it has advantages such as non-invasiveness and broad applicability, limitations exist, and the need for skilled interpretation remains. With ongoing research, including the integration of artificial intelligence, retinoscopy is expected to continue advancing and playing a vital role in eye care.

Characteristics of refractive development in children aged 4 months to 8 years in urban China: A retrospective screening analysis

PURPOSE

To conduct a large retrospective study of screening refractive error in young children.

METHODS

This retrospective study included children aged from 4 months to 8 years in Daxing District, Beijing, who underwent refractive examinations without cycloplegia. It included a cross-sectional assessment of refractive error screening for all children, and a longitudinal component for a subgroup with data available for two to five visits.

RESULTS

A total of 14,987 children were included in the cross-sectional study. In the group <1 year of age, the percentage of children with a spherical equivalent (SE) >+2.00 D or with cylinder <-1.50 D was 15.25% and 33.24%, respectively. These were significantly higher than for the 1- to 4-year-old group (SE 8.1% higher, cylinder 13.2% higher) (χ2 = 53.57, p < 0.001; χ2 = 790.39, p < 0.001). Furthermore, 34.83% of children in the 0-year-old group had amblyopia risk factors (ARFs). In the 4-year-old group, boys had a significantly longer axial length (AL) than girls (differences in the right and left eyes were 0.53 and 0.56 mm, respectively; z = 5.48 p < 0.001, z = 5.80, p < 0.001). AL increased with age, while the AL difference between boys and girls remained stable at 4-8 years of age. The percentage of children aged 5-8 years with myopia in 2020-2021 was significantly higher than that in 2018-2019 (H = 12.44, p = 0.006). In the longitudinal study of 4406 children (up to 12-month follow-up), annual changes in SE were -0.27, -0.06, 0.19 and 0.13 D between 0 and 3 years, and -0.38, -0.58, -0.70 and -0.75 D between 5 and 8 years.

CONCLUSIONS

Children's refractive error varied significantly from ages 4 months to 1 year, with a high proportion having ARFs. Children aged 5-8 years showed a trend towards myopia. The prevalence of myopia in the cross-sectional analysis in 2020-2021 was greater than in 2018-2019. Screening refraction changed minimally over a 12-month period for children aged 1-3 years, but became more myopic for children aged 5-8 years.

Congenital epiblepharon in Chinese school-age children: a cross-sectional study

PURPOSE

To investigate the prevalence and body mass index (BMI) associations of congenital lower epiblepharon in children in China and the difference in the refractive errors between children with and without epiblepharon.

METHODS

Children 6-12 years of age in Beichen District of Tianjin were screened for congenital epiblepharon from September to October 2017. All children underwent slit-lamp examination, strabismus screening, visual acuity examination and refraction. Weight and height were also recorded. The prevalence of lower epiblepharon in school-age children was evaluated, and its association with age, sex, BMI, and refractive error was analyzed.

RESULTS

A total of 28,225 children were examined; 564 had epiblepharon. The prevalence of epiblepharon was found to be, for 6-year-olds, 2.50%; for 7-year-olds, 2.13%; for 8-year-olds, 2.10%; for 9-year-olds, 1.97%; for 10-year-olds, 1.85%; for 11-year-olds, 1.67%; and for 12-year-olds, 1.19% (P < 0.05). The prevalence of overweight and obesity in children with epiblepharon was found to be 16.7% and 47.2%, respectively. The prevalence and degree of astigmatism was higher than in nonepiblepharon children. We found a possible association between severity of astigmatism and severity of epiblepharon.

CONCLUSIONS

In our study, the prevalence of epiblepharon decreased with advancing age, and the majority of children with epiblepharon were found to be overweight or obese. Epiblepharon was associated with astigmatism.

Visual Screening with Welch Allyn Spot

Objective: Analysis of refractive errors and strabismus deviations following the visual screening of patients with the Welch Allyn Spot device. Material and Methods: This paper is a prospective cross-sectional study of 4281 patients examined with the Welch Allyn Spot device acquired by Lions Club Romania - District 124. The study was conducted between May 2019 and August 2021 and was performed with the help of Lions Club Romania. Results: In the present study, 4281 patients were evaluated and divided into 5 age groups (6-12 months, 12-36 months, 3-6 years, 6-20 years, and 20-100 years). The most frequent age group was 6-20 years, being identified in 51,97% of participants. We found that the most common refractive error was astigmatism, followed by hyperopia and myopia. Thus, (RE) the refractive errors found in the right eye were: astigmatism 93.23%, hyperopia 4.63%, and myopia 1.05%, and in the left eye (LE): astigmatism 90.40%, hyperopia 6.68%, and myopia 0.84%. Of all participants, 8.81% had horizontal strabismus, esotropia being found in the RE in 4.56% of the participants and the LE in 4.74% of them. Conclusions: The pediatric population was the most affected by astigmatism and esotropia. Abbreviations: RE = right eye, LE = left eye, SD = strabismus deviation.

Evaluation of cycloplegic and noncycloplegic performance of spot vision screener in detection of amblyopia risk factors using 2021 AAPOS guidelines

PURPOSE

This research evaluates the effectiveness of the Spot Vision Screener (SVS) before and after cycloplegia to detect amblyogenic refractive errors in children.

METHODS

Children ages 3 to 10 years old were screened by the SVS before and after cycloplegia. Sensitivity, specificity, positive and negative predictive value, paired t-test, Bland-Altman plot and receiver operating characteristic area under the curve were evaluated by comparing the results of the SVS (v3.0.05) measurements with the results of the cycloplegic Topcon autorefractometer according to the 2021 guidelines of the American Association for Pediatric Ophthalmology and Strabismus.

RESULTS

Both eyes of 211 patients aged 3 to 10 years old were included. Regarding the amblyopia risk factors, the noncycloplegic SVS had 65.7 % sensitivity, 94.9 % specificity, 81.2 % positive predictive value and 89.3 % negative predictive value. The SVS's sensitivity increased from 65.7 % to 81.9 % with cycloplegia compared to noncycloplegic SVS results. The sensitivity detection of hyperopia was improved from 4.2 % to 100 % after cycloplegia. Areas under the receiver operator characteristic curve for noncycloplegic SVS and cycloplegic SVS were 0.506 (95 % CI, 0.395 to 0.646, p = 0737) and 0.905 (95 % CI, 0.915 to 0.971, p < 0.001) for hyperopia, respectively. Using the +1.64 D revised cutoff criteria for hyperopia increased sensitivity from 4.2 % to 78 %.

CONCLUSION

Noncycloplegic SVS measurements showed relatively high specificity in detecting amblyopia risk factors. The fact that noncycloplegic measurements have a very low sensitivity for hyperopia is an important weakness of the SVS, especially because hyperopia is the most frequently encountered refractive error in very young children. It should be noted that amblyogenic hyperopia may be overlooked by an SVS without cycloplegia.

Measurement Accuracy When Using Spot Vision Screener With or Without Cycloplegia in Young Adults

Purpose

There are many unclear points about the accuracy of measurement of cycloplegic refraction using the Spot Vision Screener (SVS). This study aimed to investigate the accuracy of SVS measurements with cycloplegia for myopia.

Materials and Methods

Forty-nine healthy subjects were included, and refraction was measured. Objective refractions were measured by SVS, table-mounted autorefractometer (RT7000), and handheld autorefractometer (Retinomax Screeen) at noncycloplegic and cycloplegic conditions by 1% cyclopentolate. Subjective noncycloplegic refraction was obtained by a visual acuity and refraction test performed by certified orthoptists using a cross-cylinder. One-way repeated-measures analysis of variance was used to examine whether the measured refractions fluctuate due to different reflection tests.

Results

In the noncycloplegic condition, the mean (±standard deviation) spherical equivalent (SE) measured by subjective method, SVS, RT7000, and Retinomax Screeen were -2.56 ± 3.00, -2.62 ± 2.38, -3.05 ± 2.84, and -3.26 ± 2.97, respectively. The subjective SE and objective SE measured by SVS had significantly less myopic value than the objective SE measured by two autorefractometers (p < 0.001). In the cycloplegic condition, the mean (± standard deviation) SE measured by SVS, RT7000, and Retinomax Screeen were -2.07 ± 2.66, -2.62 ± 2.98, and -2.66 ± 3.02, respectively. The objective SE measured by SVS had significantly less myopic value than SEs measured using other methods (p < 0.001). In the cycloplegic condition, SVS showed a fixed error wherein the SE was more hyperopic than that with the subjective method and SVS had a proportional error.

Conclusion

In the measurement under cycloplegic conditions, use of an autorefractometer rather than a photorefractometer such as SVS was preferable.

Diagnostic performance of the Spot vision photoscreener for the detection of exodeviation in preschool-aged children

PURPOSE

To evaluate the diagnostic performance of the Welch Allyn Spot Vision photoscreener in preschool children for detecting exotropia, the most prevalent type of strabismus among Asian children.

METHODS

Children aged 3-6 years were screened using the Spot Vision photoscreener and then underwent a complete ophthalmologic examination on the same day. A child with exodeviation ≥8 Δ in the primary position using the cover-uncover test and the alternate prism cover test was confirmed to have exotropia. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the photoscreener in detecting exotropia were calculated. Subgroup analyses were performed according to the angle of deviation (≥25 Δ vs. <25 Δ) and fusional control (good/fair vs. poor).

RESULTS

Two hundred and ten children were included in this study. Among 80 exotropia-confirmed children, 23 needed referrals for exodeviation (screening-positive) and 57 were proven to be screening-negatives with the photoscreener. The overall sensitivity, specificity, PPV and NPV of the photoscreener for detecting exotropia were 28.8%, 95.4%, 79.3% and 68.5%, respectively. The positive and negative likelihood ratios were 6.26 and 0.75, respectively. Compared with the 57 children with false-negatives (71.3%), those with true-positive results with the photoscreener had significantly larger angles of exodeviation (p = 0.02) and a higher proportion of poor fusional control (p = 0.004). The photoscreener had low sensitivity even in detecting exotropia ≥25 Δ or those with poor fusional control (35.2% and 43.6%, respectively). Approximately 65% (42 out of 64) of the children with a significant exodeviation which needed strabismus surgery were not identified by the Spot Vision Photoscreener.

CONCLUSIONS

The Spot Vision photoscreener has low sensitivity for detecting exodeviation. It should not be used alone for assessing exotropia in preschool-aged children.

Evaluation and Follow-up of Myopia Prevalence Among School-Aged Children Subsequent to the COVID-19 Home Confinement in Feicheng, China

Importance

Progression of myopia in a school-aged population due to home confinement (January to May 2021) during the COVID-19 pandemic has been previously reported. A key remaining question was whether the myopia spike in children aged 6 to 8 years persisted.

Objective

To investigate the changes in refractive status and prevalence of myopia in school-aged children 1 year after home confinement ended in China.

Design, Setting, and Participants

This cross-sectional study with a cohort substudy prospectively evaluated data from school-based photoscreening in Feicheng, China. Children aged 6 to 13 years participated in 8 screenings from 2015 to 2021.

Exposures

Noncycloplegic photorefraction was conducted using the Spot Vision photoscreener.

Main Outcomes and Measures

The main outcomes were the differences in spherical equivalent refraction (SER) and prevalence of myopia between 2020 (during home confinement) and 2021 (after home confinement). The SER was recorded for each child, and the prevalence of myopia was calculated annually for each age group.

Results

A total of 325 443 children participated in the study (51.4% boys, 48.6% girls; age range, 6 to 13 years). Compared with 2020, the mean SER of children in 2021 increased significantly for those aged 6 (0.42 diopters [D]), 7 (0.41 D), and 8 (0.33 D) years. The prevalence of myopia in 2021 was similar to in 2019 for each age group (aged 6 years: 7.9% vs 5.7%; aged 7 years: 13.9% vs 13.6%; aged 8 years: 29.5% vs 26.2%). Both the prevalence of myopia and mean SER for these children returned to their prepandemic levels.

Conclusions and Relevance

Compared with 2020, the prevalence of myopia among children aged 6 to 8 years in the 2021 screenings decreased, and the mean SER returned to prepandemic level. The refractive development in children aged 6 to 8 years may be most susceptible to environmental changes. These findings support the premise that age 6 to 8 years is a critical period for myopia development and suggest a need to focus preventive interventions for myopia control on children in this age range.

Effectiveness of the Spot Vision Screener using updated 2021 AAPOS guidelines

PURPOSE

To evaluate the Spot Vision Screener according to updated 2021 AAPOS Vision Screening Committee guidelines for instrument-based pediatric vision screen validation.

METHODS

As part of an IRB-approved ongoing prospective study, children were screened with the Spot prior to a complete examination.

RESULTS

Spot screening was successful in 1,036 of 1,090 children (95%). Forty-eight percent of participants were referred for further screening using the Spot manufacturer guidelines, and 40% of all children were found to have a 2021 amblyopia risk factor or visually significant refractive error by gold standard examination. The Spot recommendation compared reasonably well to the 2021 criteria, with an overall sensitivity of 0.88 and a specificity of 0.78. Applying updated guidelines to the Spot for hyperopia, anisometropia, and astigmatism yielded moderate-to-poor sensitivity (0.27-0.77) but excellent specificity (>0.9). The area under the curve of the receiver operating characteristic analysis demonstrates overall good prediction performance for the Spot for each diagnosis-myopia, hyperopia, astigmatism, anisometropia (range, 0.87-0.97). Results of our study suggest increasing the instrument referral criterion for astigmatism from 1.5 D (manufacturer thresholds of the screener used in this study) to 2 D in older children. Decreasing the anisometropia cut-off from 1 D to 0.75 D would improve sensitivity from 0.59 to >0.8.

CONCLUSIONS

In our study population, the overall predictive ability of the Spot is good, with a sensitivity of 0.88 and a specificity of 0.78. We recommend specific device refractive referral criteria to maximize screening effectiveness using the updated AAPOS guidelines.

Prevalence of Myopia and Its Associated Factors Among Japanese Preschool Children

Purpose

To investigate the prevalence of myopia and factors associated with spherical equivalent (SE), axial length (AL), and axial length to corneal radius of curvature (AL/CR) ratio among Japanese preschool children.

Study Design

Prospective observational study.

Methods

This cross-sectional study evaluated subjects aged 4–6 years from a preschool. Non-cycloplegic autorefraction was measured using the Spot Vision Screener, while AL and corneal radius (CR) were measured using the Myopia Master. Parental myopia and environmental factors were investigated using the myopia-related factor questionnaire. The worse eye with higher myopic SE was chosen for analysis, and multiple linear regression models was performed using AL, SE, and AL/CR ratio as dependent variables.

Results

A total of 457 out of 514 participants (239 males, 52.3%) aged 4–6 years (mean 4.77 ± 0.65 years) were included. The mean SE was 0.13 ± 0.63 D, AL was 22.35 ± 0.67 mm, CR was 7.76 ± 0.25 mm, and AL/CR ratio was 2.88 ± 0.72. The overall prevalence of myopia and high myopia were 2.9 and 0.2%, respectively. Multiple regression analysis showed that myopic SE was significantly associated with male sex (β = −0.14, p = 0.02) and parental myopia (β = −0.15, p = 0.04). Meanwhile, longer AL was significantly associated with older age (β = 0.13, p = 0.02), male sex (β = 0.44, p < 0.001), parental myopia (β = 0.24, p = 0.01), and screen time (including smartphones, tablets, and computers) (>1 h, β = 0.14, p = 0.04). A higher AL/CR was significantly associated with older age (β = 0.02, p < 0.001), male sex (β = 0.03, p < 0.001), ratio and parental myopia (β = 0.03, p = 0.02).

Conclusion

The prevalence of myopia and high myopia were 2.9 and 0.2%, respectively, among Japanese preschool children in 2021. Longer AL was associated with older age, male sex, parental myopia, and screen time in children aged 4–6 years. Children with a high risk of myopia can be identified early based on parental myopia information for early prevention.

Photoscreener results with and without cycloplegia and their reliability according to biometric parameters

PURPOSE

Our goal in this study is to compare the results of a photoscreener (Plusoptix A12C) with and without cycloplegia and to investigate its reliability as a function of biometric parameters.

METHODS

In total, 250 eyes of 125 children with a mean age of 6.77±1.59years were included in the study. The results of cycloplegic and noncycloplegic Plusoptix A12C measurements and autorefractometer with cycloplegia (CA) were compared. The spherical equivalent (SE) differences between CA and noncycloplegic Plusoptix A12C measurements (NPO) with CA and cycloplegic Plusoptix A12C measurements (CPO) were compared with axial length (AL), anterior chamber depth (ACD), corneal radius of curvature (CR), mean keratometry (meanK) and axial length/corneal radius of curvature ratio (AL/CR) values. The relationships between these were examined.

RESULTS

According to amblyopia risk factors (ARFs) based on the criteria in the 2013 AAPOS guidelines, 33 eyes (13%) in the NPO results and 34 eyes (13.6%) in the CPO results were found to be at risk for amblyopia. According to the CA results, the NPO had 67.3% sensitivity and 94.5% specificity, and the CPO 69.4% sensitivity and 89.1% specificity in detecting the values of refractive amblyopia factors determined by the AAPOS. In regard to refraction values determined by the AAPOS for amblyopia, according to CA results, the NPO had 71.4% sensitivity and 88.4% specificity in detecting myopia; 33.3% sensitivity and 93.6% specificity in detecting hyperopia; and 79.4% specificity and 71.2% sensitivity in detecting astigmatism. With regard to refraction values determined by the AAPOS for amblyopia, according to CA results, the CPO had 80.9% sensitivity and 90% specificity in detecting myopia; 13.3% sensitivity and 89.2% specificity in detecting hyperopia; and 44.9% sensitivity and 30.8% specificity in detecting astigmatism. When the SE differences between the CA and NPO values were compared with biometric parameters, a negative correlation was observed with ACD, AL, and especially AL/CR ratio.

CONCLUSION

Both the NPO and CPO showed moderate sensitivity and high specificity in detecting ARFs based on the criteria in the 2013 AAPOS guidelines. Sensitivity for detecting hyperopic risk factors was lower than for myopia and astigmatism. The CPO has no additional clinical advantage. A negative correlation was found between biometric parameters and NPO results. Thus, the NPO is more reliable in myopic children with higher axial lengths, deeper anterior chambers, and increased AL/CR ratios.

Birth weight and refractive state measured by Spot Vision Screener in children aged 40 months

Objectives

Children with retinopathy of prematurity (ROP) often have myopia. Even without ROP, birth weight and refractive state are related immediately after birth, but this relationship is reduced with increasing age. Here, we examined whether refractive state and birth weight were associated in 40-month-old children.

Methods and analysis

Of 541 children aged 40 months in Tsubame City, Japan, who underwent a medical examination between April 2018 and March 2019, this cross-sectional study enrolled 411 whose birth weights were available (76% of all).We measured the non-cycloplegic refraction using a Spot Vision Screener and correlated this with birth weight. Children were divided into three groups according to normal (2500-3500 g), high (>3500 g) or low (<2500 g) birth weights, and mean differences in spherical equivalent (SE) between the groups were analysed.

Results

The average SE for the right eye was 0.34 D (95% CI 0.28 to 0.40). Average birth weight was 3032.1 g (95% CI 2990.2 to 3073.9). Birth weight did not correlate with SE for the right eye (Pearson's correlation, r=-0.015, p=0.765) or with the degree of anisometropia (Pearson's correlation, r=-0.05, p=0.355). Furthermore, the mean SE showed no significant difference across the three groups of children with different birth weights (one-way analysis of variance, p=0.939).

Conclusion

Data on refractive states and birth weight for 411 children of similar age in one Japanese city were analysed, showing that birth weight did not influence SE, J0, J45 and the absolute degree of anisometropia at about 40 months of age.

Community based vision screening in preschool children; performance of the Spot Vision Screener and optotype testing

BACKGROUND

Children's vision screening children commonly uses optotype-based visual acuity or instrument-based methods measuring amblyogenic risk factors (ARFs).

OBJECTIVE

To compare the performance of the Spot Vision Screener (SVS) (PediaVision, Welch Allyn, NY) and a nurse-administered visual acuity screen (NVAS) in identifying ARFs and decreased visual acuity.

METHODS

A prospective, cross-sectional population-based study of preschool children in South-East Queensland, Australia. Eligible participants had both forms of screening by trained community nurses. All children with an abnormal result by either method as well as a cohort of randomly selected children who passed both assessments were assessed at a tertiary paediatric ophthalmology clinic.

RESULTS

Over a 10 month period, 2237 children (mean age; 64.4 ± 4.0 months) were screened from 38 schools. 6.4% of children failed SVS and 8.3% failed NVAS (with 3.8% overlap, failing both). The positive predictive value (PPV) in identifying either ARFs and/or reduced VA for the SVS and NVAS was 70.4% (95% Confidence Interval (CI): 61.6%-78.2%) and 60.5% (95% CI: 52.6%-67.9%) respectively. Highest PPV to detect either ARFs and/or reduced VA was achieved by a 'hybrid' method by combining failed NVAS and failed SVS: 91.0% (95% CI: 82.4 to 96.3) but this would risk children with sight impairment being missed in the community.

CONCLUSION

To our knowledge, this is the first population-based study providing detailed comparative measures of diagnostic accuracy for NVAS and SVS in preschool children. One in ten preschool children failed one or both screens. A number of children who required ophthalmic intervention were missed if only one screening method was utilized.

Effectiveness of Kanna photoscreener in detecting amblyopia risk factors

Purpose:

Amblyopia is a significant public health problem. Photoscreeners have been shown to have significant potential for screening; however, most are limited by cost and display low accuracy. The purpose of this study was validate a novel artificial intelligence (AI) and machine learning–based facial photoscreener “Kanna,” and to determine its effectiveness in detecting amblyopia risk factors.

Methods:

A prospective study that included 654 patients aged below 18 years was conducted in our outpatient clinic. Using an android smartphone, three images of each the participants’ face were captured by trained optometrists in dark and ambient light conditions and uploaded onto Kanna. Deep learning was used to create an amblyopia risk score based on our previous study. The algorithm generates a risk dashboard consisting of six values: five normalized risk scores for ptosis, strabismus, hyperopia, myopia and media opacities; and one binary value denoting if a child is “at-risk” or “not at-risk.” The presence of amblyopia risk factors (ARF) as determined on the ophthalmic examination was compared with the Kanna photoscreener.

Results:

Correlated patient data for 654 participants were analyzed. The mean age of the study population was 7.87 years. The algorithm had an F-score, 85.9%; accuracy, 90.8%; sensitivity, 83.6%; specificity, 94.5%; positive predictive value, 88.4%; and negative predictive value, 91.9% in identifying amblyopia risk factors. The P value for the amblyopia risk calculation was 8.5 × 10⁻¹⁴² implying strong statistical significance.

Conclusion:

The Kanna photo-based screener that uses deep learning to analyze photographs is an effective alternative for screening children for amblyopia risk factors.

An automatic screening method for strabismus detection based on image processing

Purpose

This study aims to provide an automatic strabismus screening method for people who live in remote areas with poor medical accessibility.

Materials and methods

The proposed method first utilizes a pretrained convolutional neural network-based face-detection model and a detector for 68 facial landmarks to extract the eye region for a frontal facial image. Second, Otsu’s binarization and the HSV color model are applied to the image to eliminate the influence of eyelashes and canthi. Then, the method samples all of the pixel points on the limbus and applies the least square method to obtain the coordinate of the pupil center. Lastly, we calculated the distances from the pupil center to the medial and lateral canthus to measure the deviation of the positional similarity of two eyes for strabismus screening.

Result

We used a total of 60 frontal facial images (30 strabismus images, 30 normal images) to validate the proposed method. The average value of the iris positional similarity of normal images was smaller than one of the strabismus images via the method (p-value<0.001). The sample mean and sample standard deviation of the positional similarity of the normal and strabismus images were 1.073 ± 0.014 and 0.039, as well as 1.924 ± 0.169 and 0.472, respectively.

Conclusion

The experimental results of 60 images show that the proposed method is a promising automatic strabismus screening method for people living in remote areas with poor medical accessibility.

Comparing School-Aged Refraction Measurements Using the 2WIN-S Portable Refractor in Relation to Cycloplegic Retinoscopy: A Cross-Sectional Study

Purpose

To assess the repeatability and agreement of refractive measurements using 2WIN-S photoscreening with the gold-standard cycloplegic retinoscope refraction.

Design

Single centre, cross-sectional study.

Methods

Spherical, cylindrical, axis, and spherical equivalent of 194 bilateral eyes of 97 children were assessed using a retinoscope and 2WIN-S. One week later, another operator repeated the 2WIN-S measurements. The primary outcome measures were to assess the repeatability and agreement between spherical equivalent, J0, and J45 readings of 2WIN-S. The repeatability of measurements was assessed by the within-subject standard deviation (2.77 Sw) and intraclass correlation coefficient (ICC). The agreement between devices was assessed using 95% limits of agreement. The extent of the agreement between cycloplegic retinoscopy and noncycloplegic 2WIN-S measurements was assessed using Bland–Altman analysis.

Results

The mean age ± SD was 10.3 ± 2.46 year (range, 4–14 years). The sphere, cylinder, and spherical equivalent measurements were found to be consistent with both apparatus (r value >0.86). ICC for SE, J0, and J45 was 0.900, 0.666, and 0.639, respectively; Sw for SE, J0, and J45 was 0.61D, 0.30D, and 0.31D, respectively; Bland–Altman analysis of retinoscopy with cycloplegia and 2WIN-S for SE was 184/194 (95%) in 95% confidence interval, and the mean value was 0.46. J0 was 184/194 (95%), and the mean value is −0.04. J45 was 181/194 (93%), and the mean value is −0.15.

Conclusion

The objective refractive measurement of 2WIN-S had good reliability and high agreement with the gold-standard retinoscopy refraction in children and adolescents. While consistency was observed, it is essential to take into consideration that it is a screening tool.

Spot Refractive Screening With or Without Maximum Atropine Cycloplegia in Preschool Chinese Children

PURPOSE

To evaluate averaged, repeat Spot Vision Screener (Welch Allyn) refractive screening with and without maximal atropine cycloplegia in preschool Chinese children.

METHODS

Refractive errors of 450 preschool children aged 3 to 6 years were measured by cycloplegic retinoscopy as the gold standard. The Spot Vision Screener was used to examine the refractive errors of these children before and after cycloplegia. The differences between the two methods were assessed using the Wilcoxon test and Bland-Altman plot. The accuracy of the Spot Vision Screener in detecting refractive errors was evaluated by receiver operating characteristic curve analysis.

RESULTS

Before cycloplegia, the Spot Vision Screener provided statistically significantly lower values of sphere (median difference: 1.50 diopters [D], 95% CI: 1.38 to 1.63 D) and spherical equivalent (median difference: 1.56 D, 95% CI: 1.50 to 1.69 D). For hyperopia of greater than 3.00 D spherical value (n = 118), the median difference between the Spot Vision Screener and cycloplegic retinoscopy was 2.63 D (95% CI: 2.50 to 2.88 D). The Bland-Altman plot showed that the difference between the results of the two examination methods was large. The sensitivity of the Spot Vision Screener for detecting refractive errors increased after the screening criteria were optimized.

CONCLUSIONS

The Spot Vision Screener was efficient in detecting anisometropia in Chinese preschool children. The Spot Vision Screener without cycloplegia underestimated the spherical value of hyperopia and the difference was larger when the cycloplegic hyperopia increased. The performance of the Spot Vision Screener without cycloplegia in detecting cycloplegic hyperopia was not complete. The instrument referral criteria of the Spot Vision Screener should be adjusted according to clinical practice, but it is not simple and users should do it with expert assistance. [J Pediatr Ophthalmol Strabismus. 2021;58(3):146-153.].

A Comprehensive Review of State Vision Screening Mandates for Schoolchildren in the United States

SIGNIFICANCE

Methods and frequency of vision screenings for school-aged children vary widely by state, and there has been no recent comparative analysis of state requirements. This analysis underscores the need for developing evidence-based criteria for vision screening in school-aged children across the United States.

PURPOSE

The purpose of this study was to conduct an updated comprehensive analysis of vision screening requirements for school-aged children in the United States.

METHODS

State laws pertaining to school-aged vision screening were obtained for each state. Additional information was obtained from each state's Department of Health and Education, through their websites or departmental representatives. A descriptive analysis was performed for states with data available.

RESULTS

Forty-one states require vision screening for school-aged children to be conducted directly in schools or in the community. Screening is more commonly required in elementary school (n = 41) than in middle (n = 30) or high school (n = 19). Distance acuity is the most commonly required test (n = 41), followed by color vision (n = 11) and near vision (n = 10). Six states require a vision screening annually or every 2 years.

CONCLUSIONS

Although most states require vision screening for some school-aged children, there is marked variation in screening methods and criteria, where the screening occurs, and grade levels that are screened. This lack of standardization and wide variation in state regulations point to a need for the development of evidence-based criteria for vision screening programs for school-aged children.

Progression of Myopia in School-Aged Children After COVID-19 Home Confinement

Question

Is home confinement due to coronavirus disease 2019 associated with the burden of myopia?

Findings

In this cross-sectional study that included 194 904 photoscreening tests conducted in 123 535 children, a substantial myopic shift (−0.3 diopters) was noted after home confinement due to coronavirus disease 2019 for children aged 6 to 8 years. The prevalence of myopia increased 1.4 to 3 times in 2020 compared with the previous 5 years.

Meaning

Home confinement due to coronavirus disease 2019 appeared to be associated with a substantial myopic shift in children; younger (aged 6-8 years) children’s refractive status may be more sensitive to environmental changes than older children, given that they are in an important period for the development of myopia.

Importance

Time spent in outdoor activities has decreased owing to home confinement for the coronavirus disease 2019 (COVID-19) pandemic. Concerns have been raised about whether home confinement may have worsened the burden of myopia owing to substantially decreased time spent outdoors and increased screen time at home.

Objective

To investigate the refractive changes and prevalence of myopia in school-aged children during the COVID-19 home confinement.

Design, Setting, and Participants

A prospective cross-sectional study using school-based photoscreenings in 123 535 children aged 6 to 13 years from 10 elementary schools in Feicheng, China, was conducted. The study was performed during 6 consecutive years (2015-2020). Data were analyzed in July 2020.

Exposures

Noncycloplegic photorefraction was examined using a photoscreener device.

Main Outcomes and Measures

The spherical equivalent refraction was recorded for each child and the prevalence of myopia for each age group during each year was calculated. The mean spherical equivalent refraction and prevalence of myopia were compared between 2020 (after home confinement) and the previous 5 years for each age group.

Results

Of the 123 535 children included in the study, 64 335 (52.1%) were boys. A total of 194 904 test results (389 808 eyes) were included in the analysis. A substantial myopic shift (approximately −0.3 diopters [D]) was found in the 2020 school-based photoscreenings compared with previous years (2015-2019) for younger children aged 6 (−0.32 D), 7 (−0.28 D), and 8 (−0.29 D) years. The prevalence of myopia in the 2020 photoscreenings was higher than the highest prevalence of myopia within 2015-2019 for children aged 6 (21.5% vs 5.7%), 7 (26.2% vs 16.2%), and 8 (37.2% vs 27.7%) years. The differences in spherical equivalent refraction and the prevalence of myopia between 2020 and previous years were minimal in children aged 9 to 13 years.

Conclusions and Relevance

Home confinement during the COVID-19 pandemic appeared to be associated with a significant myopic shift for children aged 6 to 8 years according to 2020 school-based photoscreenings. However, numerous limitations warrant caution in the interpretation of these associations, including use of noncycloplegic refractions and lack of orthokeratology history or ocular biometry data. Younger children’s refractive status may be more sensitive to environmental changes than older ages, given the younger children are in a critical period for the development of myopia.

School-based epidemiology study of myopia in Tianjin, China

PURPOSE

To study the epidemiology of myopia in school-aged children in Tianjin and the relationship between visual acuity-based screening and refraction-based screening.

METHOD

This school-based prospective cohort study was performed on children from 42 elementary schools and 17 middle schools in Tianjin, China. Totally 14,551 children, ages ranging from 5 to 16 years, were included in this study. Uncorrected visual acuity (UCVA) was determined by logarithmic tumbling E chart. Non-cycloplegic photorefraction was examined by the Spot (v2.1.4) photoscreener. The relationship between the UCVA and refractive error was investigated for different age groups.

RESULTS

The overall prevalence of myopia at this school based screen is 78.2%, ranged from 10% at age of 5 to 95% at age of 16. The most dramatic increase in prevalence is from age of 6 (14.8%) to age of 7 (38.5%). The overall prevalence of high myopia is 2.5%. UCVA is found corresponding to spherical equivalent refraction (SER) in a manner of normal distribution and is significantly affected by age. When using UCVA to estimate the prevalence of myopia, the overall sensitivity and specificity are 0.824 and 0.820, respectively. Age-dependent optimal cutoff points and 95% confident intervals of such estimation are reported.

CONCLUSIONS

Myopia is heavily affecting school-aged children in Tianjin, China. The refraction screening is preferable for myopia screening, whereas the UCVA screening results need to be interpreted in an age-dependent manner for myopia estimation.

Evaluation of the Spot Vision Screener in comparison with the orthoptic examination in visual screening in 3-5 year-old schoolchildren

PURPOSE

To evaluate the Spot Vision Screener (SVS) compared with the orthoptic examination for detection of amblyopia risk factors in preschools.

METHODS

This prospective study included children with a visual screening organized by the department of "le" (PMI) in Côte d'Or (Burgundy, France), between June 2017 and April 2018. All children were evaluated with the SVS followed by a clinical orthoptic examination. Results with the SVS were compared with those obtained by clinical orthoptic examination.

RESULTS

A total of 1236 subjects were included in the study from 100 preschools. The mean age of the children was 3.6±0.7 years, and 627 were female (50.7%). The orthoptic examination detected 308 (24.9%) children with subnormal visual acuity for age in one eye or both. In children with a history of prematurity, the orthoptic examination was more frequently abnormal (P=0.002), which was not seen with the SVS (P=0.050). The SVS screened 20 (1.6%) children with strabismus, while 40 (3.2%) were detected by orthoptic examination. At the end of the screening, the SVS detected 182 (14.7%) suspect patients while 311 (25.1%) suspect patients were detected after the orthoptic examination. Comparing SVS with orthoptic examination, agreement was fair (κ=0.4).

CONCLUSION

The SVS can be a useful device for visual screening, but agreement with the orthoptic examination was only fair. The Spot vision screener should be used in conjunction with a clinical orthoptic examination.

Accuracy of noncycloplegic photorefraction using Spot photoscreener in detecting amblyopia risk factors in preschool children in an Indian eye clinic

Purpose:

To evaluate the accuracy of Spot photoscreener (PS) as a noncycloplegic photorefractor in detecting amblyopia risk factors (ARFs) in preschool children in an Indian eye clinic setting. Also, to derive appropriate cutoff values for screening to obtain maximum sensitivity and specificity of the device in detecting ARF.

Methods:

This was a cross-sectional study conducted in the outpatient pediatric eye clinic at a tertiary eye care institute. A Spot PS was used to screen all the children between the ages of 6 months and 5 years that presented to the eye clinic from August 2018 to October 2018. This screening was followed by a complete eye examination, including cycloplegic refraction by a masked examiner. The 2013 American Association for Pediatric Ophthalmology and Strabismus (AAPOS) guidelines were considered the standard cutoff values for clinically significant refractive error in children younger than 5 years of age.

Results:

The study comprised of 219 children. The Spot PS diagnosed 135 (61.64%) children with ARF as compared with 124 (56.62%) children detected by clinic examination. For ARF detection, the Spot photoscreeneer had 85.48% sensitivity, 69.47% specificity, 78.52% positive predictive value and 78.57% negative predictive value. The sensitivity for detection of strabismus and hypermetropia was very low (42% and 36%, respectively). The 95% limits of agreement ranged from −5.48 to +5.59 diopters (D) with a bias of 0.06 D for spherical equivalent between noncycloplegic photorefraction and cycloplegic refraction.

Conclusion:

The Spot PS may be used as a screening tool to detect ARF in children younger than 5 years of age keeping its limitations in consideration. However, the performance can be improved by modifying the cutoff values for the referral.

Diagnostic test accuracy of Spot and Plusoptix photoscreeners in detecting amblyogenic risk factors in children: a systemic review and meta-analysis

PURPOSE

Amblyopia is a permanent visual impairment developed in early childhood. Recently, instrument-based photoscreeners have been widely used for vision screening to detect amblyopia risk factors, which is key for the prevention and treatment of amblyopia. This meta-analysis aims to evaluate the diagnostic test accuracy of Spot and Plusoptix photoscreeners in detecting risk factors for amblyopia in children.

METHODS

An electronic literature search was performed in October 2018 using the MEDLINE, Embase, and Web of Science databases. Twenty-one publications with a total of 5022 subjects were included. Subjects given a comprehensive examination were considered to have amblyopia or amblyogenic risk factors based on the American Association for Pediatric Ophthalmology and Strabismus (AAPOS) referral criteria guidelines.

RESULTS

The overall sensitivity for Spot and Plusoptix was 87.7% and 89.4%, respectively (p = 0.38); the specificity was 78.0% and 89.9%, respectively (p = 0.90). For subjects under 7 years old (preschool children), the overall sensitivity for Spot and Plusoptix was 91.7% and 90.2%, respectively (p = 0.81); the specificity was 82.6% and 93.0%, respectively (p = 0.46).

CONCLUSION

Both Spot and Plusoptix photoscreeners demonstrated good sensitivity and specificity in detecting amblyopia risk factors in children, especially at preschool ages. There was no significant difference in diagnostic test accuracy between them.

Can the Red Reflex Test Detect Unequal Refractive Error?

OBJECTIVE

To determine the accuracy of the red reflex test in the detection of anisometropia.

STUDY DESIGN

This prospective, single-masked study enrolled new patients younger than the age of 18 years who had not undergone pharmacologic pupillary dilation. A fellow who was masked to all clinical information illuminated both eyes with a direct ophthalmoscope in a darkened room from a distance of 1 m, assessing whether the red reflex between the 2 eyes was symmetric or asymmetric. The patient was then dilated, and cylcoplegic refraction was performed by an attending pediatric ophthalmologist. Exclusion criteria included the presence of strabismus, anisocoria, previous intraocular surgery, media opacity, leukocoria, or nystagmus. Sensitivity was compared with a null hypothesized value of 50% using a 1-sided binomial test.

RESULTS

Ninety-two patients with a mean age of 7.3 years (range 3 months to 16 years) were enrolled. With spherical anisometropia greater than or equal to 0.125 diopters, the sensitivity of the red reflex test was 90.6% and the specificity was 58.3%. With cylindrical anisometropia greater than or equal to 0.25 diopters, the sensitivity of the red reflex test was 81.3% and the specificity was 70%. Anisometropia greater than 1.5 diopters in spherical equivalent (4 patients, range -10.625 to -2.625) or cylinder (3 patients, range 1.75-2.25) was accurately detected by red reflex testing in each case.

CONCLUSIONS

The red reflex test can be an accurate screening tool to detect anisometropia when performed by an ophthalmologist.

Choosing appropriate tools and referral criteria for vision screening of children aged 4-5 years in Canada: a quantitative analysis

OBJECTIVES

To assess the diagnostic accuracy of five vision screening tools used in a school setting using sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV).

DESIGN

We compared the results of the five best evidence-based screening tools available in 2014 to the results of a comprehensive eye exam with cycloplegic refraction by a licenced optometrist. Screening included Cambridge Crowded Acuity Cards, Plusoptix S12 and Spot photoscreeners, Preschool Randot Stereoacuity Test and the Pediatric Vision Scanner (PVS). Referral criteria followed AAPOS (2013) guidelines and published norms.

SETTING

A large school in Toronto, Canada, with 25 split classrooms of junior kindergarten (JK: 4 year olds) and senior kindergarten (SK: 5 year olds) children.

PARTICIPANTS

Over 2 years, 1132 eligible children were enrolled at the school. After obtaining parental consent, 832 children were screened. Subsequently, 709 children had complete screening and optometry exam data.

MAIN OUTCOME MEASURES

The presence/absence of a visual problem based on optometrist's assessment: amblyopia, amblyopia risk factors (reduced stereoacuity, strabismus and clinically significant refractive errors) and any other ocular problem (eg, nystagmus).

RESULTS

Overall, 26.5% of the screened children had a visual problem, including 5.9% with amblyopia. Using all five tools, screening sensitivity=84% (95% CI 78 to 89), specificity=49% (95% CI 44 to 53), PPV=37% (95% CI 33 to 42), and NPV=90% (95% CI 86 to 93). The odds of having a correct screening result in SK (mean age=68.2 months) was 1.5 times those in JK (mean age=55.6 months; 95% CI 1.1 to 2.1), with sensitivity improved to 89% (95% CI 80 to 96) and specificity improved to 57% (95% CI 50 to 64) among SK children.

CONCLUSIONS

A school-based screening programme correctly identified 84% of those kindergarten children who were found to have a visual problem by a cyclopleged optometry exam. Additional analyses revealed how accuracy varies with different combinations of screening tools and referral criteria.

Evaluation of vision screening of 5-15-year-old children in three Tongan schools: comparison of The Auckland Optotypes and Lea symbols

Background

Comprehensive vision screening programmes for children are an important part of public health strategy, but do not exist in many countries, including Tonga. This project set out to assess: (1) the functional vision of children attending primary schools in Tonga and (2) how a new recognition acuity test (The Auckland Optotypes displayed on a tablet computer) compares to use of a standardised eye chart in this setting.

Methods

Children from three Tongan primary schools were invited to participate. Acuity testing was conducted using a standardised recognition acuity chart (Lea symbols) and the tablet test displaying two formats of The Auckland Optotypes. Measures of ocular alignment, stereo acuity and non‐cycloplegic photorefraction were also taken.

Results

Parents of 249 children consented to participate. One child was untestable. Only 2.8 per cent of testable children achieved visual acuity worse than 0.3 logMAR in the weaker eye. Results from the Spot Photoscreener suggested that no children had myopia or hyperopia, but that some children had astigmatism. The tablet test was practical in a community setting, and showed ±0.2 logMAR limits of agreement with the Lea symbols chart.

Conclusion

The sample of children in Tongan primary schools had good functional vision. A modified version of the tablet acuity test is a promising option for vision screening in this context.

Refractive Status and Amblyopia Risk Factors in Chinese Children with Autism Spectrum Disorder

Amblyopia risk factors in children with autism spectrum disorders (ASD) are usually hard to detect in early childhood due to poor cooperation and has not been reported in the Chinese population. We screened 168 Chinese children with ASD, aged between 3 and 8 years, and 264 age-matched neurotypical children with Spot photoscreener and basic ophthalmologic examinations. Children with ASD were found to have normal refractive status but significantly higher incidence of strabismus (16.1%), compared with control children (1.5%) (p < 0.01). Most of the cases of strabismus found in children with ASD were classified as esodeviation. Strabismus in children with ASD should be considered more seriously as an amblyopia risk factor by ophthalmologists and other healthcare professionals.

Refractive error of Saudi children enrolled in primary school and kindergarten measured with a spot screener

AIMS

To evaluate the refractive status of young Saudi schoolchildren with a "Spot Screener."

SUBJECTS AND METHODS

This cross-sectional study was conducted from January to July 2016 in Riyadh, Saudi Arabia. Children of kindergarten (3-5 years) and grades 1 and 2 (6-7 years) were screened for refractive error (RE) using the handheld Spot Screener (Welch Allyn, Skaneateles Falls, NY, USA). Data were collected on age, gender, and spectacle use. The pass/fail notation from the Spot Screener and the RE were documented. Children with a "fail" were re-tested with an autorefractor (AR). The rate of agreement was evaluated for the spherical equivalent (SE) from the Spot Screener and AR.

RESULTS

We examined 300 schoolchildren and 114 preschool children. The prevalence of RE was 22% in schoolchildren and 25% in preschoolers. There were 183 (61%) hyperopes, 110 (36.7%) myopes, 6 (2%) emmetropes, and 29 (9.7%) astigmats (>2 D cylinder) in grade 1 and 2. There were 85 (74.6%) hyperopes, 22 (19.3%) myopes, 7 (6.1%) emmetropes, and 10 (8.8%) astigmats among preschoolers. The SE differed between the AR and the Spot Screener in 17 (28%) children of 61 failed Spot Screener tests. Accommodation (9, 53%) and high astigmatism (8, 47%) were the main underlying causes of the difference. The Spot Screener could identify RE for the first time in 51 (17%) schoolchildren and 26 (22%) preschoolers. End-users suggested that Spot Screener was child-friendly and quick to test RE.

CONCLUSIONS

The Spot Screener could be a good initial screening tool for RE in young schoolchildren.

Clinical Performance of the Spot Vision Photo Screener before and after Induction of Cycloplegia in Children

Aim

To compare the clinical performance of the Spot Vision Screener used to detect amblyopia risk factors (ARFs) in children before and after induction of cycloplegia; the children were referred because they met the screening criteria of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS).

Methods

The Spot Vision Screener and a standard autorefractometer were used to examine 200 eyes of 100 children aged 3–10 years, before and after cycloplegia induction, in terms of ARFs. Sensitivity, specificity, and positive and negative predictive values for the detection of significant refractive errors were measured using the AAPOS referral criteria. It was explored that Spot Screener data were affected by cycloplegia. The extent of agreement between cycloplegic/noncycloplegic photoscreening data and cycloplegic autorefraction measurements was assessed using Wilcoxon and Spearman correlation analyses.

Results

The Spot's sensitivity was improved from 60.9% to 85.3% and specificity from 94.9% to 87.4% with cycloplegia compared to cycloplegic standard autorefractometer results. The positive predictive value of Spot was 75.7%, and the negative predictive value was 90.4% without cycloplegia. With cycloplegia, the positive predictive value of Spot was 63.6% and the negative predictive value was 95.8%.

Conclusions

The Spot Screener afforded moderate sensitivity and high specificity prior to cycloplegia. The sensitivity and negative predictive value improved after induction of cycloplegia. Examiners should be aware of the effects of cycloplegia on their findings.

Pseudoesotropia in Chinese Children: A Triphasic Development of the Interepicanthal Folds Distance-to-Interpupillary Distance Ratio and Its Changing Perception

Purpose

To delineate the development of the interepicanthal fold distance (IEFD) to interpupillary distance (IPD) in Chinese children, and to quantify how their ratio (EFDPD ratio) affects parent’s judgment on whether a child’s two eyes appear misaligned.

Methods

The values of IPD and IEFD were measured in 750 children, aged between 3 and 17 years. The developmental trend of EFDPD ratio was established. Two hundred parents were shown a series of pictures of children with varying EFDPD ratios and asked to judge whether the child in each picture demonstrated misaligned eyes. Based on the parent’s responses, psychometric functional associations with EFDPD ratios were established.

Results

The EFDPD ratios were significantly higher (0.63 ± 0.027) and showed little change among children from 3 to 6 years of age (p = 0.704). During the age of seven to 12 years, however, the EFDPD ratio significantly decreased (p < 0.001) before stabilizing at 0.59 ± 0.023 by the ages of 13 to 17 years (p = 0.376). Children with EFDPD ratios > 0.65 were more likely to be perceived as strabismic by the parents, while children with an EFDPD ratio < 0.55 were rarely perceived as so. As many as 30% of the children aged between 3 and 6 years demonstrated EFDPD ratios > 0.65, and this number reduced to 5% by the age of 12 years.

Conclusions

The development of the EFDPD ratio in Chinese children shows a triphasic pattern, with a large value before the age of 6 years, a quick drop between 7 and 12 years, and little change after 13 years of age. As the EFDPD ratio declines, fewer children appear as strabismic.

Level of Evidence IV

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Compared performance of Spot and SW800 photoscreeners on Chinese children

Purpose

To evaluate the effectiveness of Spot photoscreener and SW800 vision screener in detecting amblyopia risk factors in Chinese children between 4 and 6 years of age.

Methods

One hundred and thirteen children (226 eyes) underwent complete ophthalmologic examination, cycloplegic retinoscopy refraction, prism cover tests and photoscreen using both Spot (v2.1.4) and SW800 (v1.0.1.0) photoscreeners. The agreement of results obtained from photoscreener and retinoscopy was evaluated by paired t-test as well as Pearson correlation test. The sensitivity and specificity of detecting amblyopia risk factors were calculated based on the American Association of Pediatric Ophthalmology and Strabismus 2013 guidelines. The overall effectiveness of detecting amblyopia risk factors by using either photoscreener was analysed by receiver operating characteristic (ROC) curves.

Results

A strong linear agreement was observed between Spot and retinoscopy (p<0.01) in aspects of spherical equivalent (SE, Pearson’s r=0.95), dioptre sphere (DS, r=0.97), dioptre cylinder (DC, r=0.84) and horizontal deviation (Hdev, r=0.91), with overall −0.17 D myopic shift of SE. Significant correlation was also shown between SW800 and retinoscopy (p<0.01) in aspects of SE (r=0.90), DS (r=0.93), DC (r=0.82) and Hdev (r=0.80), with overall −0.12 D myopic shift of SE. The overall sensitivity and specificity in detecting amblyopia risk factors were 94.0% and 80.0% for Spot and 88.8% and 81.1% for SW800.

Conclusion

The measurements of Spot and SW800 photoscreener showed a strong agreement with cycloplegic retinoscopy refraction and prism cover tests. The performance of both screeners in detecting individual amblyopia risk factors is satisfactory. ROC analysis indicates that the Spot and SW800 performed very similarly in detecting amblyopia risk factors.

Tribal Odisha Eye Disease Study # 4: Accuracy and utility of photorefraction for refractive error correction in tribal Odisha (India) school screening

Purpose

To compare the photorefraction system (Welch Allyn Spot™) performance with subjective refraction in school sight program in one Odisha (India) tribal district.

Methods

In a cross-sectional study school students, aged 5-15 years, referred after the preliminary screening by trained school teachers received photoscreening and subjective correction. The photoscreener was compared to subjective refraction in the range of +2D to -7.5D. Statistical analysis included Friedman nonparametric test, Wilcoxon signed-rank test, linear regression, and Bland-Altman plotting.

Results

The photoscreener was used in 5990 children. This analysis included 443 children (187 males, 256 females, and the mean age was 12.43 ± 2.5 years) who received both photorefraction and subjective correction, and vision improved to 6/6 in either eye. The median spherical equivalent (SE) with spot photorefraction was 0.00 D (minimum -5.0D; maximum +1.6 D), and with subjective correction was 0.00D (minimum -6.00 D; maximum +1.5 D). The difference in the SE between the two methods was statistically significant (P < 0.001) using Friedman nonparametric test; it was not significant for J 45 and J 180 (P = 0.39 and P = 0.17, respectively). There was a good correlation in linear regression analysis (R2 = 0.84) and Bland-Altman showed a good agreement between photorefraction and subjective correction in the tested range.

Conclusion

Photorefraction may be recommended for autorefraction in school screening with reasonable accuracy if verified with a satisfactory subjective correction. The added advantages include its speed, need of less expensive eye care personnel, ability to refract both eyes together, and examination possibility in the native surrounding.

Performance of Photoscreener in Detection of Refractive Error in All Age Groups and Amblyopia Risk Factors in Children in a Tribal District of Odisha: The Tribal Odisha Eye Disease Study (TOES) # 3

PURPOSE

To evaluate effectiveness of Welch Allyn Spot Vision Screener in detecting refractive error in all age groups and amblyopia risk factors in children in a tribal district of India.

METHODS

All participants received dry retinoscopy and photorefraction; children also received cycloplegic retinoscopy. Statistical analysis included Bland-Altman and coefficient of determination (R2).

RESULTS

Photoscreener could not elicit a response in 113 adults and 5 children of 580 recruited participants. In Bland-Altman analysis mean difference of Spot screener spherical equivalent (SSSE) and dry retinoscopy spherical equivalent (DRSE) was 0.32 diopters (D) in adults and 0.18 D in children; this was an overestimation of hyperopia and underestimation of myopia. In Bland-Altman analysis of SSSE and cycloplegic retinoscopy spherical equivalent (CRSE) the mean difference was -0.30 D in children; this was an overestimation of myopia and underestimation of hyperopia. In regression analysis the relationship between SSSE and DRSE was poor in adults (R2 = 0.50) and good in children (R2 = 0.92). Cubic regression model for Spot versus cycloretinoscopy in children was: CRSE = 0.34 + 0.85 SSSE - 0.01 SSSE2 + 0.006 SSSE3. It was 87% accurate. Sensitivity and specificity of Spot in detecting amblyopia risk factors (2013 American Association for Pediatric Ophthalmology and Strabismus [AAPOS] criteria) was 93.3% and 96.9% respectively. Sensitivity of Spot screener in detection of amblyopia was 72%.

CONCLUSIONS

Photoscreener has 87% accuracy in refraction in children. Its value could be used for subjective correction tests.

TRANSLATIONAL RELEVANCE

Photoscreening could complement traditional retinoscopy to address refractive error in children in a resource-limited facility region.

Instrument-based pediatric vision screening

PURPOSE OF REVIEW

The purpose is to review currently available instruments for vision screening in young children.

RECENT FINDINGS

Instrumentation continues to evolve. Although the current generation of photoscreeners and autorefractors strive to identify amblyopia risk factors, newer technology aims to directly identify amblyopia in young children. Acceptance of instrument-based vision screening for this population has led to increased reimbursement for the procedure in primary care practices.

SUMMARY

Instrument-based vision screening in the young child is an accepted method of screening for amblyopia. Innovations in instrumentation will continue to improve its implementation.