Development of visual acuity in preschool children as measured with Landolt C and Tumbling E charts

Combination of 2 test methods, single-picture optotype visual acuity chart and spot™ vision screener, in the eye health screening program for 3-year-old children in Tokyo: A retrospective, observational study

To evaluate the usefulness of the Tokyo Metropolitan Government's Eye Health Screening Program for 3-year-old children, which combines the Single-Picture Optotype Visual Acuity Chart (SPVAC) and Spot™ Vision Screener (SVS) tests. This was a retrospective, observational, matched study. Patients who underwent the eye health screening program and had abnormalities were classified into 3 groups according to the outcomes of the SPVAC (SPVAC-passed, SPVAC-P; SPVAC-failed, SPVAC-F) and SVS (SVS-passed, SVS-P; SVS-failed, SVS-F) tests as follows: SPVAC-P/SVS-F, SPVAC-F/SVS-P, and SPVAC-F/SVS-F. We evaluated the age at examination, SPVAC and SVS test success rates, and SVS refractive power. Additionally, the rates of refractive error, amblyopia, and strabismus were compared among the 3 groups. The SPVAC-P/SVS-F, SPVAC-F/SVS-P, and SPVAC-F/SVS-F groups comprised 158, 28, and 74 eyes, respectively. The mean age was 37.4 months. The success rates of the SPVAC and SVS tests were 69.8% and 96.2%, respectively. The mean SVS hyperopia value in the SPVAC-F/SVS-F group (2.71 ± 1.50 D) was significantly higher than that of the SPVAC-P/SVS-F group. The mean SVS astigmatism and myopia values were -2.21 diopter (D) ± 1.09 D and -3.40 ± 1.82 D, respectively; they did not differ significantly from that of the SPVAC-P/SVS-F group. Significant differences were observed in the refractive error, amblyopia, and strabismus rates among the 3 groups. Regarding disease determination, no significant difference was observed among participants who passed and failed the SPVAC test, regardless of the outcome of the other test. However, a significant difference was observed between those passing and failing the SVS tests. The SPVAC method used to screen 3-year-old children should be modified to commence at 42 months of age or be replaced with a single Landolt C test. The SVS test is useful for screening younger patients. Furthermore, the SVS test showed that the degree of hyperopia was higher in patients who did not pass the SPVAC test.

Developing a Novel Pediatric Eye Chart Assessing Visual Acuity by Minimum Separable Threshold

The purpose of this study was to develop a new pediatric acuity chart that can assess the minimum separation threshold by incorporating the minimum separation threshold into the picture. To overcome the design limitations of the Landolt ring, two designs of highly versatile minimum separable thresholds that can be easily incorporated into a picture were created: a black, filled circle (the "Circle") and a segment (the "Square"), both with the same break as in the Landolt ring. The three designs-the Landolt ring, Circle, and Square-were used to evaluate and compare the differences in the visual acuity of 21 healthy adults. No significant differences were observed between the results of the visual acuity tested with the Landolt ring, Circle, and Square (Landolt ring vs. Circle: p = 0.92, Landolt ring vs. Square: p = 0.31, Circle vs. Square: p = 0.40). The Bland-Altman analysis revealed no fixed errors between the Landolt ring and Circle and between the Landolt ring and Square (95% CI: -0.09-0.08, -0.09-0.12). Proportional errors were also not observed (p = 0.68, p = 0.41). The Landolt ring, Circle, and Square designs obtained equal results in visual acuity, thus achieving the successful development of a novel pediatric visual acuity chart using these designs.

Vision-related quality of life in patients with childhood-onset craniopharyngioma

Quality of life (QoL) is a critical component of aftercare in survivors of childhood-onset craniopharyngioma (CP). Visual impairment adversely affects QoL after CP. This study assessed the frequency of visual impairment in patients with CP and its association with QoL. This study analyzed vision-related QoL in patients recruited 2000-2019 in the prospective cohort studies KRANIOPHARYNGEOM 2000/2007. Ophthalmologic examinations were performed at diagnosis, three, 12, and 36 months, respectively after the diagnosis. The QoL (PEDQOL) scores, were also evaluated at three, 12, and 36 months, respectively after the CP diagnosis. Multivariable logistic regression was used to analyze factors associated with visual impairment during follow-up. One-hundred twenty patients were included in this study. On ophthalmological examination, visual impairment was observed in the majority of the patients (n = 84, 70%) at CP diagnosis. After surgery, vision was restored in 27 patients (32%) with visual impairment at diagnosis. In the first (p = 0.017) and third (p = 0.011) year after diagnosis, parents of patients with visual impairment reported lower social functioning (family). Reduced autonomy was found three years after diagnosis in self- (p = 0.029) and parental (p = 0.048) assessments. Next to visual impairment at diagnosis, no additional risk factors for visual impairment during follow-up could be identified. Visual impairment has a clinically relevant impact on QoL after CP. The visual status at CP diagnosis determines the visual outcome during follow-up. Early detection of visual impairment, regular QoL assessments, and risk-appropriate aftercare are recommended.Clinical Trial Registration KRANIOPHARYNGEOM 2000 (Clinical trial registration number: NCT00258453) and KRANIOPHARYNGEOM 2007 (Clinical trial registration number: NCT01272622).

Measures and variability with age of low contrast acuity and near stereoacuity in children

CLINICAL RELEVANCE

Low contrast acuity (LCA) and near stereoacuity (NS) testing are integral to the comprehensive assessment of sensory visual function in children. However, routine ophthalmological evaluations seldom take these measures into consideration. Additionally, there is limited literature regarding the normative values of these parameters in children.

BACKGROUND

This study investigated LCA and NS measures and their variability in children with normal visual acuity. The aim was to provide a benchmark for distinguishing normal measures from abnormal ones.

METHODS

A prospective observational study was conducted in primary and secondary schools across North India. The participants numbered 240 children, aged between 3 and 15 years. They were split into 12 smaller groups of 20 participants in each age group. Only participants with normal monocular uncorrected visual acuity, no refractive error, normal birth history, and no systemic ailments, were recruited. All the participants underwent a complete ophthalmic examination and non-cycloplegic retinoscopy. LCA was measured, using the low contrast Lea number chart at three metres. NS was measured using the Randot® stereo test at 40 cm.

RESULTS

The percentages of males and females, were found to be 55%, and 45%, respectively (p = 0.093). The mean NS was found to be 38.7 ± 11.5 arcsecs in the 3-9-year age group, and 26.7 ± 5.6 arcsecs in the 9-15-year age group (p-value <0.001). The mean NS showed an increasing trend up to 9 years of age. The mean LCA was 64.4 ± 20.1 in the age group of 3-8 years, and 76.38 ± 11.39 in the age group of 8-15 years (p-value <0.001). Considerable variability was noted in the LCA in the younger age group (p-value = 0.000).

CONCLUSIONS

LCA and NS mature gradually during childhood. LCA stabilises after the age of 8, while NS stabilises after the age of 9.

The impact of early exposure to general anesthesia on visual and neurocognitive development

Every year millions of children are exposed to general anesthesia while undergoing surgical and diagnostic procedures. In the field of ophthalmology, 44,000 children are exposed to general anesthesia annually for strabismus surgery alone. While it is clear that general anesthesia is necessary for sedation and pain minimization during surgical procedures, the possibility of neurotoxic impairments from its exposure is of concern. In animals there is strong evidence linking early anesthesia exposure to abnormal neural development. but in humans the effects of anesthesia are debated. In humans many aspects of vision develop within the first year of life, making the visual system vulnerable to early adverse experiences and potentially vulnerable to early exposure to general anesthesia. We attempt to address whether the visual system is affected by early postnatal exposure to general anesthesia. We first summarize key mechanisms that could account for the neurotoxic effects of general anesthesia on the developing brain and review existing literature on the effects of early anesthesia exposure on the visual system in both animals and humans and on neurocognitive development in humans. Finally, we conclude by proposing future directions for research that could address unanswered questions regarding the impact of general anesthesia on visual development.

A reassessment and comparison of the Landolt C and tumbling E charts in managing amblyopia

Current criteria for amblyopia do not account for difference in visual acuity charts. This prospective observational study analyzed 100 children younger than 10 years treated at a tertiary referral center. Visual acuity was separately tested in each eye using Landolt C and tumbling E charts in a random order. For each chart, receiver operating characteristic curve analysis was performed to determine the best cutoff for visual acuity score. Main outcome measures included the difference in visual acuity scores between the two charts, the feasibility of repeated testing of visual acuity in each eye, and amblyopia cutoff values for each chart. Mean logMAR visual acuity scores obtained by tumbling E chart were significantly better than those obtained by Landolt C chart. For amblyopia, the best cutoff values were <  + 0.14 (20/27 Snellen equivalent) for tumbling E chart and <  + 0.24 (20/35 Snellen equivalent) for Landolt C chart. For children under 10 years old, visual acuity scores for tumbling E chart were significantly better than those for Landolt C chart. We suggest that amblyopia management in children should account for age and the type of visual acuity chart used.

Differences between children with Down syndrome and typically developing children in adaptive behaviour, executive functions and visual acuity

In children with Down syndrome (DS) development of visual, motor and cognitive functions is atypical. It is unknown whether the visual impairments in children with DS aggravate their lag in cognitive development. Visual impairment and developmental lags in adaptive behaviour and executive functions were assessed in 104 children with DS, 2–16 years, by comparing their adaptive behaviour, executive functions and visual acuity (distant and near) scores against published age-matched norm scores of typically developing children. Associations between these lags were explored. Mean (± SEM) differences to age-matched norms indicated reduced performance in DS: Vineland Screener questionnaire, − 63 ± 3.8 months; task-based Minnesota Executive Function Scale (MEFS), − 46.09 ± 2.07 points; BRIEF-P questionnaire, 25.29 ± 4.66 points; BRIEF parents’ and teachers’ questionnaire, 17.89 ± 3.92 points and 40.10 ± 3.81 points; distant and near visual acuity, 0.51 ± 0.03 LogMAR and 0.63 ± 0.03 LogMAR (near − 0.11 ± 0.04 LogMAR poorer than distant). Adaptive behaviour (Vineland-S) correlated with the severity of visual impairment (r = − 0.396). Children with DS are severely impaired in adaptive behaviour, executive functions and visual acuities (near visual acuity more severely impaired than distant visual acuity). Larger impairment in adaptive behaviour is found in children with larger visual impairment. This supports the idea that visual acuity plays a role in adaptive development.

A Quantification Procedure for Interior Performance of Architectural Openings Associated with Dye-Sensitized Solar Cells

Windows with various colors are important design elements used widely ranging from traditional architecture to contemporary buildings to express the architectural façade, the interior atmosphere, and so on. Recently, there is a possibility that solar cells can be used to replace windows with various colors. In particular, attempts to manufacture windows using Dye-Sensitized Solar Cells (DSSCs) are actively underway. Accordingly, there is a need to determine physical and environmental performances of DSSCs. This study attempted a methodological approach to evaluate indoor environmental performance of windows and DSSCs. The concept of color gamut overage normally used in the field of displays was utilized to evaluate color expressions. In addition, a standard visual inspection table suggested by the International Ophthalmological Society was used to evaluate the recognition of shapes. This study compared performances between RGB color windows and DSSCs using the two above previous concepts. Measurement data showed that most DSSCs performed poorly in comparison with architectural color windows. However, some DSSCs showed good enough performances that could be used as alternatives of architectural color windows. Green DSSCs with VLT 18% had a color gamut similar to clear glasses. Blue DSSCs with VLT 18% were found to have similar or better shape recognition than current architectural color windows. Based on these results, limitations of DSSCs as alternatives of architectural color windows and their future development directions are suggested.

Diagnostic accuracy and agreement between visual acuity charts for detecting significant refractive errors in preschoolers

BACKGROUND

Preschool vision screenings are considered to be cost-effective methods to identify children with vision disorders. The children of this age group are poor at communicating their symptoms and hence screening is mandated. This study is aimed at estimating the diagnostic accuracy and agreement of Lea, HOTV and E visual acuity charts for detecting significant refractive errors.

METHODS

A cross-sectional study was conducted, in which monocular unaided vision assessment of each study participant was performed with Lea, HOTV and E charts. Stereo acuity was measured with the Randot Preschool Test and a comprehensive eye examination including dilatation was performed. Significant refractive error was defined as hyperopia > 3.25 D, myopia > 2.00 D, astigmatism > 1.50 D, anisometropia if interocular difference > 1.00 D for hyperopia, > 3.00 D for myopia or > 1.50 D for astigmatism. Sensitivity, specificity, positive and negative predictive values were estimated. Bland-Altmann plots were generated to help identify the level of agreement between the vision charts.

RESULTS

A total of 256 eyes were analysed. Lea, HOTV and E had sensitivities of 87.8 per cent, 90.2 per cent and 90.2 per cent, respectively. Specificity and positive predictive values were better for HOTV (77.3 per cent, 65.5 per cent) and Lea (75 per cent, 62.6 per cent), compared to E chart (69.8 per cent, 58.7 per cent). Negative predictive values for Lea, HOTV and E charts were 92.8 per cent, 93.8 per cent and 93.8 per cent, respectively. Bland-Altmann analysis showed good agreement between Lea and HOTV, Lea and E, and HOTV and E visual acuity charts. The acuity difference was least between Lea and HOTV charts (0.1 logMAR). Eighty-five (33.2 per cent) eyes had significant refractive errors. Eighty (94.1 per cent) eyes were astigmatic.

CONCLUSION

The diagnostic accuracy of the visual acuity charts was high for the identification of significant refractive errors in preschool children. There was very good agreement between the visual acuity charts.

The development of human visual cortex and clinical implications

The primary visual cortex (V1) is the first cortical area that processes visual information. Normal development of V1 depends on binocular vision during the critical period, and age-related losses of vision are linked with neurobiological changes in V1. Animal studies have provided important details about the neurobiological mechanisms in V1 that support normal vision or are changed by visual diseases. There is very little information, however, about those neurobiological mechanisms in human V1. That lack of information has hampered the translation of biologically inspired treatments from preclinical models to effective clinical treatments. We have studied human V1 to characterize the expression of neurobiological mechanisms that regulate visual perception and neuroplasticity. We have identified five stages of development for human V1 that start in infancy and continue across the life span. Here, we describe these stages, compare them with visual and anatomical milestones, and discuss implications for translating treatments for visual disorders that depend on neuroplasticity of V1 function.

Should tumbling E go out of date in amblyopia screening? Evidence from a population-based sample normative in children aged 3-4 years

Aims

To determine a normative of tumbling E optotype and its feasibility for visual acuity (VA) assessment in children aged 3-4 years.

Methods

A cross-sectional study of 1756 children who were invited to participate in a comprehensive non-invasive eye exam. Uncorrected monocular VA with crowded tumbling E with a comprehensive ophthalmological examination were assessed. Testability rates of the whole population and VA of the healthy children for different age subgroups, gender, school type and the order of testing in which the ophthalmological examination was performed were evaluated.

Results

The overall testability rate was 95% (92% and 98% for children aged 3 and 4 years, respectively). The mean VA of the first-day assessment (first-VA) and best-VA over 2 days’ assessments was 0.14 logMAR (95% CI 0.14 to 0.15) (decimal=0.72, 95% CI 0.71 to 0.73) and 0.13 logMAR (95% CI 0.13 to 0.14) (decimal=0.74, 95% CI 0.73 to 0.74). Analysis with age showed differences between groups in first-VA (F(3,1146)=10.0; p<0.001; η2=0.026) and best-VA (F(3,1155)=8.8; p<0.001; η2=0.022). Our normative was very highly correlated with previous reported HOTV-Amblyopia-Treatment-Study (HOTV-ATS) (first-VA, r=0.97; best-VA, r=0.99), with 0.8 to 0.7 lines consistent overestimation for HOTV-ATS as described in literature. Overall false-positive referral was 1.3%, being specially low regarding anisometropias of ≥2 logMAR lines (0.17%). Interocular difference ≥1 line VA logMAR was not associated with age (p=0.195).

Conclusions

This is the first normative for European Caucasian children with single crowded tumbling E in healthy eyes and the largest study comparing 3 and 4 years old testability. Testability rates are higher than found in literature with other optotypes, especially in children aged 3 years, where we found 5%–11% better testability rates.

Zagreb Amblyopia Preschool Screening Study: near and distance visual acuity testing increase the diagnostic accuracy of screening for amblyopia

AIM

To present and evaluate a new screening protocol for amblyopia in preschool children.

METHODS

Zagreb Amblyopia Preschool Screening (ZAPS) study protocol performed screening for amblyopia by near and distance visual acuity (VA) testing of 15 648 children aged 48-54 months attending kindergartens in the City of Zagreb County between September 2011 and June 2014 using Lea Symbols in lines test. If VA in either eye was >0.1 logMAR, the child was re-tested, if failed at re-test, the child was referred to comprehensive eye examination at the Eye Clinic.

RESULTS

78.04% of children passed the screening test. Estimated prevalence of amblyopia was 8.08%. Testability, sensitivity, and specificity of the ZAPS study protocol were 99.19%, 100.00%, and 96.68% respectively.

CONCLUSION

The ZAPS study used the most discriminative VA test with optotypes in line as they do not underestimate amblyopia. The estimated prevalence of amblyopia was considerably higher than reported elsewhere. To the best of our knowledge, the ZAPS study protocol reached the highest sensitivity and specificity when evaluating diagnostic accuracy of VA tests for screening. The pass level defined at ≤0.1 logMAR for 4-year-old children, using Lea Symbols in lines missed no amblyopia cases, advocating that both near and distance VA testing should be performed when screening for amblyopia.

A coalition partnership of vision health through a health-promoting school program for primary school students in Taiwan

Myopia, the most common refractive error, is the most common cause of avoidable visual impairment among children and has reached epidemic proportions among children and young adults in urban areas of East and Southeast Asia that contain populations of Chinese ancestry. Moreover, vision health is an important theme of the health-promoting school program issued by the Ministry of Education in Taiwan. The aim of this study is to assess the impact of pre- and post-intervention proposed by the health-promoting school (HPS) model. The objectives are to understand whether the HPS model influenced the vision screening results and the attitude, knowledge level, and vision care behavior of the students involved. A prospective cohort study design was used to evaluate a vision health program. Four elementary schools, local education authorities, and one university in northern Taiwan established a coalition partnership to design a six-month program to combat myopia among students. The target population was 6668 school children from local elementary schools. For the purpose of this study, the outcome of visual acuity testing (in logMAR) was analyzed with a sampling of 373 school children (aged 11-12 years old) who were chosen from high prevalence of poor vision classes. After the HPS program, the attitudes, behaviors, and knowledge levels of the school children regarding vision health were significantly improved. The pre-intervention mean logMAR of all participating students ( N = 373) was -.10, which increased to -.19 after the intervention. Analysis using the Wilcoxon signed-rank test showed that the logMAR value was significantly improved after the intervention ( t = 2.13, p < 0.05). Our findings highlight the relevance and effectiveness of the coalition's efforts, which reinforces the usefulness of co-operatively implementing the HPS program.

Comparison of visual acuity results in preschool children with lea symbols and Bailey-Lovie E chart

Purpose:

To compare visual acuity with two visual acuity charts in preschool children.

Materials and Methods:

Visual acuity measurement with Lea symbols and Bailey-Lovie tumbling E chart was performed on children between 3 and 6 years of age. Visual acuity data from the two charts were analyzed with Bland-Altman plot to determine the limits of agreement. The Wilcoxon signed test was performed in children aged 3-4 years and in children aged 5-6 years separately to evaluate the influence of age. The inter-eye difference between the two charts were further analyzed with the paired t-test. A p value > 0.05 was considered statistically significant.

Results:

A total of 47 children were enrolled for the study. The average logarithm of the Minimum Angle of Resolution (LogMAR) monocular visual acuity with Lea symbols (0.17 ± 0.13) was better than the Bailey-Lovie tumbling E chart (0.22 ± 0.14). The mean difference between Bailey-Lovie tumbling E chart and Lea symbol chart was 0.05 ± 0.12 in logMAR units. A second analysis eliminating outliers showed the same result but lower differences (n = 43, 0.05 ± 0.05 logMAR units). Visual acuity results between the two charts in children aged 3-4 years showed a significant difference (p = 0.000), but not for children aged 5-6 years (p = 0.059). Inter-eye differences between the two charts was not statistically significant (p = 0.77).

Conclusion:

Bailey-Lovie tumbling E chart is comparable to the Lea symbols chart in pre-school children. But preference should be given to Lea symbols for children aged 3-4 years as the symbols are more familiar than a directional test for this age group.

Uncorrected visual acuity and noncycloplegic autorefraction predict significant refractive errors in Taiwanese preschool children

PURPOSE

To investigate the accuracy of uncorrected visual acuity (UCVA), stereopsis, and noncycloplegic autorefraction (NCAR) tests performed by vision-screening technicians and to determine the best referral criteria when using these methods to screen for significant refractive errors in preschool children.

DESIGN

Retrospective, case-control, and cross-sectional study.

PARTICIPANTS

We reviewed 1000 records for a population-based preschool vision-screening program. The target conditions were defined as myopia ≤-3.0 diopters (D), hyperopia ≥ 4.5 D, astigmatism ≥ 2.0 D, and anisometropia ≥ 2.0 D.

METHODS

Receiver operating characteristic (ROC) curve was used to calculate optimal referral cutoff values. The examination results obtained by the vision-screening technicians were compared with those obtained by a pediatric ophthalmologist, which were considered the gold standard.

MAIN OUTCOME MEASURES

The efficacies (sensitivity, specificity, positive predictive value, and negative predictive value) of different tests were evaluated.

RESULTS

In 7.0% (95% confidence interval [CI], 5.3-8.7) of the children, at least 1 eye showed 1 of the target conditions. If only the right eyes were considered, the prevalence of target conditions was 4.2% (95% CI, 2.9-5.5). The ROC curve analysis indicated that the NCAR cylinder test (cutoff value ≥ 0.875 D) was the best test for screening target conditions. With regard to age groups, UCVA ≤ 0.75 (Snellen equivalent) and ≤ 0.85 were the best referral criteria for ages ≤ 4 years and ≥ 5 years, respectively. Combining the UCVA test with the NCAR test (the child was referred after failing both tests) increased specificity without significantly decreasing sensitivity.

CONCLUSIONS

The UCVA and NCAR tests performed by vision-screening technicians are adequately sensitive and specific for preschool vision screening. The ROC curve analysis was used for determining the appropriate screening criteria for these tests, and combining the tests increased their accuracy. The screening criteria should be age dependent. When analyzing the test accuracy in ophthalmic problems, if the disease of interest does not symmetrically (in terms of disease severity and prevalence) involve both eyes, the prevalence based on only 1 eye should be interpreted with caution.