Optic disc and retinal vascular features in first 6 years of Chinese children.

Purpose: Retinal microvasculature plays an important role in children's fundus lesions and even in their later life. However, little was known on the features of normal retina in early life. The purpose of this study was to explore the normal retinal features in the first 6 years of life and provide information for future research. Methods: Children, aged from birth to 6 years old and diagnosed with various unilateral ocular diseases were included. Venous phase fundus fluorescein angiography images with the optic disc at the center were collected. Based on the ResUNet convolutional neural network, optic disc and retinal vascular features in the posterior retina were computed automatically. Results: A total of 146 normal eyes of 146 children were included. Among different age groups, no changes were shown in the optic disc diameter (y = -0.00002x + 1.362, R2 = 0.025, p = 0.058). Retinal vessel density and fractal dimension are linearly and strongly correlated (r = 0.979, p < 0.001). Older children had smaller value of fractal dimension (y = -0.000026x + 1.549, R2 = 0.075, p = 0.001) and narrower vascular caliber if they were less than 3 years old (y = -0.008x + 84.861, R2 = 0.205, p < 0.001). No differences were in the density (y = -0.000007x + 0.134, R2 = 0.023, p = 0.067) and the curvature of retinal vessels (lnC = -0.00001x - 4.657, R2 = 0.001, p = 0.667). Conclusions: Age and gender did not impact the optic disc diameter, vessel density, and vessel curvature significantly in this group of children. Trends of decreased vessel caliber in the first 3 years of life and decreased vessel complexity with age were observed. The structural characteristics provide information for future research to better understand the developmental origin of the healthy and diseased retina.

Prevalence of vision conditions in children in a very remote Australian community.

CLINICAL RELEVANCE: Understanding the prevalence of vision conditions in a population is critical for determining the most appropriate strategies for detecting and correcting eye conditions in a community. This is particularly important in very remote regions where access to vision testing services is limited. BACKGROUND: Although recent studies have provided detailed analyses of the prevalence of vision conditions in Aboriginal and/or Torres Strait Islander children in urban and regional areas of Australia, there is a paucity of research examining vision conditions in children in remote regions. Importantly, a significant proportion of the population in remote and very remote regions identify as Aboriginal and/or Torres Strait Islander people. METHODS: Comprehensive eye examinations were provided to 193 primary school children in a very remote Australian region. Ninety eight percent of children identified as Aboriginal and/or Torres Strait Islander. The eye examination included measures of visual acuity, cycloplegic autorefraction, binocular vision and accommodative function, ocular health and colour vision. Previous history of eye examinations and refractive correction were assessed through parental questionnaire. RESULTS: Although the average unaided vision in the population was good (mean: 0.02 ± 0.13 logMAR) and the prevalence of reduced unaided visual acuity (>0.3 logMAR in either eye) was low (4%), vision conditions were detected in 32% of children. The most common conditions were clinically significant refractive errors (18% of children) and binocular vision or accommodative disorders (16%). Of the total population of children tested, 10% had previously had an eye examination, and 2% were reported to have previously been prescribed spectacles. CONCLUSIONS: In this population of children in a very remote Australian region, up to 1 in 3 children had a vision condition, with many of these conditions being uncorrected and undetected. These findings highlight the important need for additional resources to be made available to very remote communities for the detection and correction of vision conditions in childhood.

Relationship between visual and neurodevelopmental measures at 2 years with visual acuity and stereopsis at 4.5 years in children born at risk of neonatal hypoglycaemia.

PURPOSE: Mild to moderate vision loss affects many children and can negatively impact a child's early literacy and academic achievement. Nevertheless, there is no consensus on which factors present in early childhood indicate the need for long-term ophthalmic follow up, particularly in children with a history of perinatal adversity. This study identified the relationship between visual, cognitive, motor and demographic factors at 2 years of age and visual acuity (VA) and stereoacuity at 4.5 years of age. METHODS: Five hundred sixteen children identified as being at risk of neonatal hypoglycaemia were recruited soon after birth. At 2 years of age, binocular VA, stereoacuity and non-cycloplegic refraction were measured and a clinical neuro-developmental assessment with the Bayley Scales of Infant Development III (BSID-III) was conducted by a trained examiner. Monocular VA and stereoacuity were measured at 4.5 years of age. RESULTS: Three hundred twenty-eight children completed both the 2 and 4.5 year vision and neurodevelopmental assessments. Multiple linear regression showed oblique astigmatism and motor function at 2 years were significantly associated with VA at 4.5 years of age, while spherical equivalent refraction, motor scores and stereoacuity at 2 years were significantly associated with stereoacuity at 4.5 years of age. BSID-III motor scores had the best sensitivity (81.8%) and specificity (51.5%) for identifying impaired stereoacuity at 4.5 years. However, all measures at 2 years were poorly associated with VA at 4.5 years old. CONCLUSION: Vision and neurodevelopmental measures at 2 years were poorly associated with visual function at 4.5 years of age. However, lower scores on tests of motor function at 2 years may be associated with vision abnormalities, particularly reduced stereopsis, at 4.5 years of age and referral for comprehensive vision assessment for these children may be warranted.

Adherence to home-based videogame treatment for amblyopia in children and adults.

Clinical relevance: Home-based videogame treatments are increasingly popular for amblyopia treatment. However, at-home treatments tend to be done in short sessions and with frequent disruptions, which may reduce the effectiveness of binocular visual stimulation. These treatment adherence patterns need to be accounted for when considering dose-response relationships and treatment effectiveness.Background: Home-based videogame treatments are increasingly being used for various sensory conditions, including amblyopia ('lazy eye'), but treatment adherence continues to limit success. To examine detailed behavioural patterns associated with home-based videogame treatment, we analysed in detail the videogame adherence data from the Binocular tReatment of Amblyopia with VideOgames (BRAVO) clinical trial (ACTRN12613001004752).Methods: Children (7-12 years), teenagers (13-17 years) and adults (≥ 18 years) with unilateral amblyopia were loaned iPod Touch devices with either an active treatment or placebo videogame and instructed to play for a total of 1-2 hours/day for six weeks at home. Objectively-recorded adherence data from device software were used to analyse adherence patterns such as session length, daily distribution of gameplay, use of the pause function, and differences between age groups. Objectively-recorded adherence was also compared to subjectively-reported adherence from paper-based diaries.Results: One hundred and five of the 115 randomised participants completed six weeks of videogame training. Average adherence was 65% (SD 37%) of the minimum hours prescribed. Game training was generally performed in short sessions (mean 21.5, SD 11.2 minutes), mostly in the evening, with frequent pauses (median every 4.1 minutes, IQR 6.1). Children played in significantly shorter sessions and paused more frequently than older age groups (p < 0.0001). Participants tended to over-report adherence in subjective diaries compared to objectively-recorded gameplay time.Conclusion: Adherence to home-based videogame treatment was characterised by short sessions interspersed with frequent pauses, suggesting regular disengagement. This complicates dose-response calculations and may interfere with the effectiveness of treatments like binocular treatments for amblyopia, which require sustained visual stimulation.

Do reduced visual acuity and refractive error affect classroom performance?

The role of visual acuity and refractive errors in the academic performance of children is controversial due to the variable quality of the research in this area and the mixed findings reported. This review aims to provide clarity by reviewing and critiquing relevant peer-reviewed publications and also summarises what is known regarding the visual demands of modern classroom environments. The outcomes of this review suggest that while a number of studies have investigated the role of vision in relation to children's academic performances, the veracity of the evidence obtained from the majority of these studies is undermined by methodological limitations. Comparisons between studies are constrained by differences in experimental designs, instrumentation and sample characteristics. Despite these limitations, the weight of evidence suggests there is an association between academic performance and both visual acuity and refractive error in children. However, well-designed experimental studies are necessary to further understand the relationship between these parameters.

Visual information processing skills are associated with academic performance in Grade 2 school children.

PURPOSE: This study evaluated the association between performance on visual information processing tests and academic performance in school children. METHODS: Visual-motor integration (VMI), the Developmental Eye Movement (DEM) test, visual acuity and stereoacuity were assessed in 222 Grade 2 children (mean age: 7.90 ± 0.33 years). Academic performance was assessed using standardized tests of reading and mathematics (PAT-R and PAT-M). Linear regression analyses examined associations between visual information processing (VMI and DEM) and academic measures, adjusting for school socio-economic background and age. Receiver operating characteristic (ROC) analysis was used to assess the ability of the tests to identify children with below average academic performance. RESULTS: Visual-motor integration (VMI) and DEM (horizontal time) were most strongly associated with PAT-R and PAT-M. Linear regression models explained 28.6% of variance in PAT-R (VMI: standardized regression coefficient = 0.31, p < 0.01; DEM horizontal time: -0.28, p < 0.01) and 24.1% of variance in PAT-M (VMI: standardized regression coefficient = 0.29, p < 0.01; DEM horizontal time: -0.16, p = 0.02). Receiver operating characteristic (ROC) curve analysis indicated that VMI was most strongly associated with below average PAT-R (area under curve [AUC] of 0.74 [95% CI: 0.67-0.81]) and PAT-M (AUC of 0.73 [95% CI: 0.66-0.81]). CONCLUSION: Visual-motor integration (VMI) was most strongly associated with reading and mathematics scores in school children. A child's academic performance can be an important factor in their optometric management. The ability of clinical tests to identify children at risk of underachieving academically provides additional support to clinicians in managing their patients.

Validity of the +1.50 plus lens screening test as a predictor of uncorrected moderate hyperopia.

PURPOSE: Screening for uncorrected hyperopia in school children is important given its association with poorer visual function and academic performance. However, standard distance visual acuity screening may not detect low to moderate hyperopia. The plus lens test is used to screen for hyperopia in many school screening protocols, but has not been well validated. The current study investigated the effectiveness of the plus lens test to identify hyperopia in school children. METHODS: Participants included Grade 2 school children. Monocular distance visual acuity (logMAR letter chart) was measured unaided, and then through a +1.50D lens, known as the plus lens test. Cycloplegic refraction was undertaken to classify moderate hyperopia (≥+2.00D). Sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV) were calculated for commonly used cut-offs for the plus lens test: 6/6, 6/9 and less than two lines difference between unaided acuity and acuity through the plus lens test. RESULTS: The sample included 59 children (mean age 7.2 ± 0.4 years). Fourteen (24%) children were classified as having uncorrected hyperopia. The sensitivity and specificity of the +1.50 plus lens test for identifying hyperopia were 0% and 98% respectively for a 6/6 cut-off, 29% and 91% for 6/9 cut-off, and 50% and 76% for a <2 line reduction between unaided acuity and acuity through the plus lens test. Receiver Operating Curve (ROC) analysis revealed area under curves of 0.69 based on acuity through the plus lens test, and 0.65 for a reduction in acuity through the plus lens test. CONCLUSIONS: The plus lens test has low sensitivity for detecting uncorrected hyperopia using traditional cut-offs of 6/9 or better. This raises questions about the role of the plus lens test in school screening batteries.

Optical coherence tomography in paediatric clinical practice.

Optical coherence tomography is a non-invasive ocular imaging technique that is frequently used in the diagnosis and monitoring of optic nerve or retinal disease. Advances in optical coherence tomography speed and image processing capability allow increased use of the modality in clinical practice, especially in younger children. This review outlines the challenges involved in imaging children, highlights the technological progress, the importance of acquiring normative data and, finally, focuses on the clinical applicability of optical coherence tomography in our paediatric population with various ocular conditions.

Vision and academic performance in primary school children.

PURPOSE: Vision is considered important for academic performance in children; however, the evidence in this area tends to be inconsistent and inconclusive. This study explored the association between vision function and visual information processing measures and standardised academic achievement scores in Grade 3 Australian children. METHODS: Participants included 108 Grade 3 primary school children (M = 8.82 ± 0.32 years) from three state primary schools in South-East Queensland. All participants underwent a standard vision screening, including distance visual acuity (VA), binocular vision testing and stereoacuity (SA). A computer-based battery of visual information processing tests including the Development Eye Movement (DEM) test, Visual Sequential Memory (VSM) and Symbol Search (SS) was also administered. Australian National Assessment Program for Literacy and Numeracy (NAPLAN) scores across five subtests of academic performance were obtained for each child: Reading, Writing, Spelling, Grammar/Punctuation and Numeracy. RESULTS: The DEM adjusted horizontal and vertical times were most strongly associated with all of the NAPLAN subtest scores (p < 0.01), adjusted for age and the socio-economic status of the school; the DEM ratio was not significantly associated with any of the NAPLAN subtests. VSM and SS scores were significantly associated with one or more NAPLAN subtests, as were worse and better eye VA; SA showed no significant association with any of the NAPLAN subtests. CONCLUSIONS: Performance on the horizontal and vertical DEM subtests was most strongly associated with academic performance. These data, in conjunction with other clinical data, can provide useful information to clinicians regarding their prescribing and management philosophy for children with lower levels of uncorrected refractive error and binocular vision anomalies.

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.

Test-retest reproducibility of accommodative facility measures in primary school children.

BACKGROUND: To determine the test-retest reproducibility of accommodative facility (AF) measures in an unselected sample of UK primary school children. METHODS: Using ±2.00 DS flippers and a viewing distance of 40 cm, AF was measured in 136 children (range 4-12 years, average 8.1 ± 2.1) by five testers on three occasions (average interval between successive tests: eight days, range 1-21 days). On each occasion, AF was measured monocularly and binocularly, for two minutes. Full datasets were obtained in 111 children (81.6 per cent). RESULTS: Intra-individual variation in AF was large (standard deviation [SD] = 3.8 cycles per minute [cpm]) and there was variation due to the identity of the tester (SD = 1.6 cpm). On average, AF was greater: (i) in monocular compared to binocular testing (by 1.4 cpm, p < 0.001); (ii) in the second minute of testing compared to the first (by 1.3 cpm, p < 0.001); (iii) in older compared to younger children (for example, AF for 4/5-year-olds was 3.3 cpm lower than in children ≥ 10 years old, p = 0.009); and (iv) on subsequent testing occasions (for example, visit-2 AF was 2.0 cpm higher than visit-1 AF, p < 0.001). After the first minute of testing at visit-1, only 36.9 per cent of children exceeded published normative values for AF (≥ 11 cpm monocularly and ≥ 8 cpm binocularly), but this rose to 83.8 per cent after the third test. Using less stringent pass criteria (≥ 6 cpm monocularly and ≥ 3 cpm binocularly), the equivalent figures were 82.9 and 96.4 per cent, respectively. Reduced AF did not co-exist with abnormal near point of accommodation or reduced visual acuity. CONCLUSIONS: The results reveal considerable intra-individual variability in raw AF measures in children. When the results are considered as pass/fail, children who initially exhibit normal AF continued to do so on repeat testing. Conversely, the vast majority of children with initially reduced AF exhibit normal performance on repeat testing. Using established pass/fail criteria, the prevalence of persistently reduced AF in this sample is 3.6 per cent.

Prevalence of refractive errors in children in India: a systematic review.

Uncorrected refractive error is an avoidable cause of visual impairment which affects children in India. The objective of this review is to estimate the prevalence of refractive errors in children ≤ 15 years of age. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed in this review. A detailed literature search was performed to include all population and school-based studies published from India between January 1990 and January 2017, using the Cochrane Library, Medline and Embase. The quality of the included studies was assessed based on a critical appraisal tool developed for systematic reviews of prevalence studies. Four population-based studies and eight school-based studies were included. The overall prevalence of refractive error per 100 children was 8.0 (CI: 7.4-8.1) and in schools it was 10.8 (CI: 10.5-11.2). The population-based prevalence of myopia, hyperopia (≥ +2.00 D) and astigmatism was 5.3 per cent, 4.0 per cent and 5.4 per cent, respectively. Combined refractive error and myopia alone were higher in urban areas compared to rural areas (odds ratio [OR]: 2.27 [CI: 2.09-2.45]) and (OR: 2.12 [CI: 1.79-2.50]), respectively. The prevalence of combined refractive errors and myopia alone in schools was higher among girls than boys (OR: 1.2 [CI: 1.1-1.3] and OR: 1.1 [CI: 1.1-1.2]), respectively. However, hyperopia was more prevalent among boys than girls in schools (OR: 2.1 [CI: 1.8-2.4]). Refractive error in children in India is a major public health problem and requires concerted efforts from various stakeholders including the health care workforce, education professionals and parents, to manage this issue.

Factors influencing eye-care seeking behaviour of parents for their children in Nigeria.

BACKGROUND: The eye-care seeking behaviour of parents for their children has a role to play in increasing or reducing the prevalence of childhood blindness. In Nigeria, little or no work has been done in this area. Hence, this study was carried out with a view to assisting eye-care professionals plan better program regimens and also to help them identify various elements that either facilitate or hinder eye-care seeking behaviour of parents for their school age children. METHODS: This was a qualitative narrative study. Data were collected using in-depth interviews (IDIs) and focus group discussions (FGDs). Thirty-five parents and 10 eye-care practitioners were selected by random sampling and homogenous sampling methods, respectively. Parents were selected, based on those who sought care and those who did not seek care for their children after a school screening exercise. Collected data were analysed qualitatively by transcribing the voice recordings of interview sessions into textual data and themes were raised. RESULTS: Four FGDs and 13 IDIs were conducted. Parents were more likely to seek care for manifest conditions than for conditions they could not perceive. A family history of ocular disease and repetitiveness of complaints facilitated parents to seek eye care for their children. The cost of eye-care services was a major barrier. Logistics such as fixing a doctor's appointment, getting time off work and long waiting periods at the clinic were also reported as barriers. Fear of treatment options and family interferences were also mentioned. CONCLUSION: Parents have some concerns and challenges in seeking eye care for their children. This study recommends that more work be done through planned awareness programs to educate parents and help them overcome the concerns and barriers that hinder them from seeking eye care for their children.

Vision screening at two years does not reduce the prevalence of reduced vision at four and a half years of age.

BACKGROUND: There is currently insufficient evidence to recommend vision screening for children < 36 months of age. This study assessed the effect of comprehensive vision screening, as well as the sensitivity of age-appropriate vision tests, at two years of age on habitual visual acuity at 4.5 years of age. METHODS: Children born at risk of neonatal hypoglycaemia (n = 477) underwent vision assessment at 54 ± 2 months of age including measurement of monocular and binocular habitual visual acuity, assessment of binocularity and stereopsis. Of these children, 355 (74.4 per cent) had also received vision screening at two years of age (mean age = 24± 1 months), while 122 were not screened. RESULTS: Eighty (16.8 per cent) children were classified as having reduced vision at 4.5 years of age, but the prevalence of reduced vision did not differ between children who had previously been screened at two years of age and those who had not (15.5 per cent versus 20.5 per cent, p = 0.153). However, children with reduced vision at 4.5 years of age were more likely to have had visual abnormalities requiring referral detected at two years of age (p = 0.02). Visual acuity and mean spherical equivalent autorefraction measurements were also worse (higher values) in two-year-old children who were later classified with reduced habitual visual acuity (p = 0.031 and p = 0.001, respectively). Nevertheless, unaided binocular visual acuity, non-cycloplegic refractive error, and stereopsis at two years all showed poor sensitivity and specificity for predicting visual outcomes at 4.5 years of age. CONCLUSION: Our findings do not support the adoption of early vision screening in children as current vision tests suitable for use with two-year-old children have poor sensitivity for predicting mild-moderate habitual vision impairment at 4.5 years of age.

Does Hofstetter's equation predict the real amplitude of accommodation in children?

PURPOSE: The aim was to determine the distribution and associated factors of accommodative amplitude (AA) in six- to 12-year-old children and compare the results with those calculated using Hofstetter's formula. METHODS: In a cross-sectional study in 2015, random sampling was done from urban and rural populations of Shahroud, northern Iran. Participating schoolchildren were examined for manifest, cycloplegic and subjective refraction, as well as uncorrected vision and visual acuity. The AA was measured with Donders' push-up method using a ruler. The near point of convergence (NPC) was also measured. RESULTS: Of the 6,624 selected children, 5,620 participated in the study and after applying the exclusion criteria, the final analyses were done on data from 5,444 schoolchildren. The mean age of the final sample was 9.24 ± 1.71 years (from six to 12 years) and 53.6 per cent (n = 2,919) were boys. Mean measured AA was 14.44 D (95 per cent confidence interval [CI]: 14.33-14.55). In all age groups, the mean measured AA was less than the predicted mean value calculated with the Hofstetter's equation. Mean measured AA was 14.44 D (95 per cent CI: 14.28-14.59) and 14.45 D (95 per cent CI: 14.29-14.6) in boys and girls, respectively (p = 0.926). AA significantly declined with age (coefficient: -0.18, 95 per cent CI: -0.23 to -0.12, p < 0.001). Mean AA in emmetropic, myopic and hyperopic children was 14.31 D, 17.30 D and 14.87 D, respectively. Older age (coefficient = -0.18), living in rural areas (coefficient = -0.48) and NPC (coefficient = 0.47) inversely related with AA and higher AA was associated with a shift of the spherical equivalent refraction toward myopia (coefficient = -0.41). CONCLUSION: The differences among groups with different types of refractive error and high AA in children with myopia are important findings of this study. The results of the present study suggest that Hofstetter's formula provides inaccurate AA estimates in children and thus, the interpretation of this index requires further population-based studies in different racial and ethnic groups.

Optical Coherence Tomography Evolution in a Case of X-Linked Juvenile Retinoschisis: 15 Years of Follow-Up.

PURPOSE: We present the evolution of X-linked juvenile retinoschisis (XLRS) in a male patient using optical coherence tomography (OCT) with a long-term follow-up time of 15 years. CASE DESCRIPTION: A 10-year-old male patient presented at the Medical Retina Department of our hospital complaining for blurred vision in both eyes. At the initial presentation in 2001, his best corrected visual acuity (BCVA) was 6/12 in both eyes on the Snellen chart. Based on clinical and OCT findings, the diagnosis of XLRS was made, and it was confirmed by genetic testing. No treatment was performed, but the patient was regularly examined. His BCVA and OCT findings remained relatively stable from 2001 to 2012, when BCVA decreased to 6/18 and 6/24 in the right and left eye, respectively. In 2016, his BCVA was 6/24 and 6/36 in right and left eye, respectively, while OCT depicted significant macular thinning, accompanied by irregularities of the foveal contour in both eyes. CONCLUSION: Patients with XLRS should be monitored regularly to evaluate the progression of the disease and manage the potential complications.

Effect of simulated refractive error on adult visual acuity for paediatric tests.

PURPOSE: Although vanishing optotype preferential-looking tasks are commonly used to measure visual acuity (VA), the relative sensitivity of these tests to refractive error is not well understood. To address this issue, we determined the effect of spherical and astigmatic simulated refractive errors on adult VA measures obtained using vanishing optotypes, picture optotypes and Sloan letters. METHODS: VA was determined uniocularly for adults under conditions of spherical (0.0-3.0 DS; n = 23) and astigmatic (0.0-3.0 DC at 90° and 180°; n = 20) defocus using the Cardiff Acuity Test (vanishing optotypes), crowded linear Lea Symbols (picture-optotype recognition task) and the Early Treatment of Diabetic Retinopathy Study (ETDRS) letter chart. RESULTS: The Cardiff Acuity Test over-estimated VA compared with the Lea Symbols and ETDRS charts in both focused and defocused conditions. The mean difference between the Cardiff Acuity Test and the ETDRS chart was 0.31 logMAR (95% limits of agreement (LOA) 0.10-0.52 logMAR) in focused conditions and 0.64 logMAR (95% LOA 0.25-1.05 logMAR) with 3D of spherical defocus. Defocus degraded VA on all charts, however there was a significant chart-by-defocus interaction whereby the Cardiff Acuity Test was more resistant to the effects of both spherical (P < 0.0001) and cylindrical (P < 0.001) optical defocus than the recognition acuity tasks at all defocus levels. CONCLUSION: Although the Cardiff Acuity Test provides an easy method for VA measurement in infants and toddlers, there is a considerable overestimation of VA compared with recognition acuity tasks particularly in the presence of defocus. A simple correction factor (of for example three lines overestimate) cannot be applied to Cardiff acuity measures as there is increasing over-estimation of VA with increasing defocus. Infants with significant refractive error may fall within normal visual acuity ranges for the Cardiff Acuity Test.

A comparison of cycloplegic autorefraction and retinoscopy in Indian children.

BACKGROUND: Correction of significant refractive errors in childhood helps in preventing amblyopia and strabismus. India has a huge demand for eye-care services related to uncorrected refractive errors with limited manpower resources. This can be overcome by autorefractors, which are free of operator bias, do not need skilled eye-care professionals and can be operated with ease. Hence, the purpose of this study, the first in the Indian population, was to determine the accuracy of autorefraction compared to traditional retinoscopy under cycloplegia. METHOD: A cross-sectional study of all children meeting our inclusion criteria was conducted from July till October 2011 in a tertiary eye care centre. Children underwent cycloplegic (cyclopentolate plus tropicamide) refraction with an auto-refractometer (Topcon KR-8900) and traditional retinoscopy and the results were compared. Patients were divided into three groups: Group 1: Myopia and myopic astigmatism, Group 2: Hyperopia and hyperopic astigmatism and Group 3: Mixed astigmatism. Clinically significant difference was defined as either of more than 0.50 D difference in sphere, more than 0.5 D difference in cylinder or more than 20 degrees difference in axis. RESULTS: The left eyes of 294 children (148 male) were included in the study. Mean age was 8.22 ± 3.47 years. Clinically significant differences were noted in 13.22 per cent of eyes in Group 1, 15.09 per cent of eyes in Group 2 and 20.90 per cent of eyes in Group 3. Clinically significant differences were more common in children aged less than six years (25 per cent) compared to older children (9.19 per cent). Comparing the sphere, cylinder, spherical equivalent and length of power vector values gained by autorefraction and retinoscopy, no statistically significant differences were found in any group. CONCLUSION: Autorefraction with Topcon KR-8900 can be used reliably in Indian children older than six years, if conducted under cycloplegia. In mixed astigmatism and children less than six years, it should be corroborated with retinoscopy.

Development of a Pediatric Visual Field Test.

PURPOSE: We describe a pediatric visual field (VF) test based on a computer game where software and hardware combine to provide an enjoyable test experience. METHODS: The test software consists of a platform-based computer game presented to the central VF. A storyline was created around the game as was a structure surrounding the computer monitor to enhance patients' experience. The patient is asked to help the central character collect magic coins (stimuli). To collect these coins a series of obstacles need to be overcome. The test was presented on a Sony PVM-2541A monitor calibrated from a central midpoint with a Minolta CS-100 photometer placed at 50 cm. Measurements were performed at 15 locations on the screen and the contrast calculated. Retinal sensitivity was determined by modulating stimulus in size. To test the feasibility of the novel approach 20 patients (4-16 years old) with no history of VF defects were recruited. RESULTS: For the 14 subjects completing the study, 31 ± 15 data points were collected on 1 eye of each patient. Mean background luminance and stimulus contrast were 9.9 ± 0.3 cd/m2 and 27.9 ± 0.1 dB, respectively. Sensitivity values obtained were similar to an adult population but variability was considerably higher - 8.3 ± 9.0 dB. CONCLUSIONS: Preliminary data show the feasibility of a game-based VF test for pediatric use. Although the test was well accepted by the target population, test variability remained very high. TRANSLATIONAL RELEVANCE: Traditional VF tests are not well tolerated by children. This study describes a child-friendly approach to test visual fields in the targeted population.

Comparison of objective refraction in darkness to cycloplegic refraction: a pilot study.

BACKGROUND: The aim was to assess non-cycloplegic objective refraction in darkness using an open-field auto-refractor, and furthermore to compare it with distance cycloplegic subjective refraction and distance cycloplegic retinoscopy in the light, in children and young adults. METHODS: Twenty-three, visually-normal, young-adults (46 eyes) ages 23 to 31 years, and five children (10 eyes) ages five to 12 years, participated in the study. The spherical component of their refraction ranged from -2.25 D to +3.75 D with a mean of +1.80 D, and a mean cylinder of -0.70 D. Three techniques were used to assess refractive error. An objective measure of the non-cycloplegic refractive state was obtained using an open-field autorefractor (WAM-5500) after five minutes in the dark to allow for dissipation of accommodative transients and relaxation of accommodation. In addition, both distance retinoscopy and subjective distance refraction were performed following cycloplegia (Cyclopentolate, 1%) using conventional clinical procedures. All measurements were obtained on the same day within a single session. The spherical component of the refraction was compared among the three techniques in both the children and adults. RESULTS: There was no significant difference in spherical refraction among the three techniques: non-cycloplegic objective refraction in the dark, distance cycloplegic retinoscopy and distance cycloplegic subjective refraction, in either the adults [F(2, 137) = 0.79, p = 0.45] or the children [F(2, 27) = 0.47, p = 0.62]. Mean difference in the spherical component between refraction in the dark and the cycloplegic distance retinoscopy was -0.34 D (r = 0.89) in the adults and +0.14 D (r = 0.96) in the children. The mean difference in spherical component between refraction in the dark and the cycloplegic distance subjective refraction was -0.25 D (r = 0.92) in the adults and -0.05 D (r = 0.95) in the children. CONCLUSION: Comparison of the spherical refractive component between the three techniques was not significantly different and furthermore, they were highly correlated in both the children and adults in this pilot study. Non-cycloplegic refraction in the dark may provide a reliable adjunct or alternative to conventional cycloplegic refraction in both children and young adults.