Red and green defocus curves and duochrome test in different age groups / Curvas de desenfoque rojo y verde y prueba de duocromo en diferentes grupos de edad

Purpose: To compare the eye defocus curves (DCs) obtained with stimuli on red, green, and white backgrounds and to investigate the applicability of the duochrome test (DT) in different age groups. Methods: 12 elderly (ELD: 59.3 ± 3.9 years) and 8 young (YG: 22.1 ± 1.1 years) subjects were recruited. An optometric assessment with the DT was carried out to obtain the subjective refraction at distance. DCs at distance on green, white, and red backgrounds were measured and the following parameters were deduced: dioptric difference between red-green, green-white, red-white focal positions (minima of the DCs), best corrected visual acuity (BCVA), and widths of the DCs for red, green, and white. Results: The DC difference between the green-white focal positions (mean ± standard deviation) was -0.12±0.17 diopters (D) (ELD, p = 0.012) and -0.11±0.12 D (YG, p = 0.039), while the red-white difference was not statistically significant. The DC red-green difference was 0.20±0.16 D (ELD, p = 0.002) and 0.18±0.18 D (YG, p = 0.008). The ELD BCVA with green background was significantly worse than BCVA with red (p = 0.007) and white (p = 0.007). The mean value of the DC's width in ELD for green (1.01±0.36 D) was higher than for red (0.77±0.21 D) and for white (0.84±0.35 D), but with no statistical significance. Conclusion: Both age groups showed a slight focusing preference for red when using white light. Moreover, ELD showed a worse BCVA with a green compared to a red background. Despite these results deduced by DC analyses, these aspects do not compromise the possibility of using the DT in clinical practice both in the young and in the elderly. Furthermore, the difference of about 0.20 D between red-green DC in both groups confirms the clinical appropriateness of the widespread use of 0.25 D step as the standard minimum difference in power between correcting lenses.(AU)

Assessing the role of visual dysfunctions in the association between visual symptomatology and the use of digital devices / Evaluación del papel de las disfunciones visuales en la asociación entre la sintomatología visual y el uso de dispositivos digitales

Purpose: To evaluate the association between visual symptoms and use of digital devices considering the presence of visual dysfunctions. Methods: An optometric examination was conducted in a clinical sample of 346 patients to diagnose any type of visual anomaly. Visual symptoms were collected using the validated SQVD questionnaire. A threshold of 6 hours per day was used to quantify the effects of digital device usage and patients were divided into two groups: under and above of 35 years old. A multivariate logistic regression was employed to investigate the association between digital device use and symptoms, with visual dysfunctions considered as a confounding variable. Crude and the adjusted odds ratio (OR) were calculated for each variable. Results: 57.02 % of the subjects reported visual symptoms, and 65.02% exhibited some form of visual dysfunction. For patients under 35 years old, an association was found between having visual symptoms and digital device use (OR = 2.10, p = 0.01). However, after adjusting for visual dysfunctions, this association disappeared (OR = 1.44, p = 0.27) and the association was instead between symptoms and refractive dysfunction (OR = 6.52, p < 0.001), accommodative (OR = 10.47, p < 0.001), binocular (OR = 6.68, p < 0.001) and accommodative plus binocular dysfunctions (OR = 46.84, p < 0.001). Among patients over 35 years old, no association was found between symptoms and the use of digital devices (OR = 1.27, p = 0.49) but there was an association between symptoms and refractive dysfunction (OR = 3.54, p = 0.001). Conclusions: Visual symptoms are not dependent on the duration of digital device use but rather on the presence of any type of visual dysfunction: refractive, accommodative and/or binocular one, which should be diagnosed.(AU)

Study of stereopsis using a depth sensation detection platform equipped with computer vision technology (DALE3D) / Estudio de estereopsis mediante una plataforma de detección de sensaciones de profundidad equipada con tecnología de visión por ordenador (DALE3D)

Background and objectives: The invention described herein is a prototype based on computer vision technology that measures depth perception and is intended for the early examination of stereopsis. Materials and methods: The prototype (software and hardware) is a depth perception measurement system that consists on: (a) a screen showing stereoscopic models with a guide point that the subject must point to; (b) a camera capturing the distance between the screen and the subject's finger; and (c) a unit for recording, processing and storing the captured measurements. For test validation, the reproducibility and reliability of the platform were calculated by comparing results with standard stereoscopic tests. A demographic study of depth perception by subgroup analysis is shown. Subjective comparison of the different tests was carried out by means of a satisfaction survey. Results: We included 94 subjects, 25 children and 69 adults, with a mean age of 34.2 ± 18.9 years; 36.2 % were men and 63.8 % were women. The DALE3D platform obtained good repeatability with an interclass correlation coefficient (ICC) between 0.94 and 0.87, and coefficient of variation (CV) between 0.1 and 0.26. Threshold determining optimal and suboptimal results was calculated for Randot and DALE3D test. Spearman's correlation coefficient, between thresholds was not statistically significant (p value > 0.05). The test was considered more visually appealing and easier to use by the participants (90 % maximum score). Conclusions: The DALE3D platform is a potentially useful tool for measuring depth perception with optimal reproducibility rates. Its innovative design makes it a more intuitive tool for children than current stereoscopic tests. Nevertheless, further studies will be needed to assess whether the depth perception measured by the DALE3D platform is a sufficiently reliable parameter to assess stereopsis.(AU)

Mean cycloplegic refractive error in emmetropic adults – The Tehran Eye Study / Error refractivo ciclopléjico medio en adultos emétropes: estudio ocular de Teherán

Purpose: In children under 20 years, refractive development targets a cycloplegic refractive error of +0.5 to +1.5D, while presbyopes over 40 years generally have non-cycloplegic errors of ≥ +1D. Some papers suggest these periods are separated by a period of myopic refractive error (i.e., ≤ –0.50D), but this remains unclear. Hence, this work investigates the mean cycloplegic refractive error in adults aged between 20 – 40 years. Methods: In 2002 a cross-sectional study with stratified cluster sampling was performed on the population of Tehran, providing cycloplegic and non-cycloplegic refractive error data for the right eyes of 3,576 participants, aged 30.6 ± 18.6 years (range: 1–86 years). After grouping these data into age groups of 5 years, the refractive error histogram of each group was fitted to a Bigaussian function. The mean of the central, emmetropized peak was used to estimate the mean refractive error without the influence of myopia. Results: The mean cycloplegic refractive error at the emmetropized peak decreased from +1.10 ± 0.11D (95 % confidence interval) to +0.50 ± 0.04D before 20 years and remains stable at that value until the age of 50 years. The non-cycloplegic refractive error also sees a stable phase at 0.00 ± 0.04D between 15 – 45 years. After 45 – 50 years both cycloplegic and non-cycloplegic refractive error become more hypermetropic over time, +1.14 ± 0.12D at 75 years. Conclusions: The cycloplegic refractive error in adults is about +0.50D between 20 – 50 years, disproving the existence of the myopic period at those ages.(AU)

Binocular vision parameters and visual performance in bilateral keratoconus corrected with spectacles versus rigid gas-permeable contact lenses / Parámetros de visión binocular y rendimiento visual en queratocono bilateral corregido con gafas versus lentes de contacto rígidos permeables al gas

Purpose: To analyze binocular vision of individuals aged 18 to 35 years diagnosed with keratoconus, utilizing spectacles and rigid gas-permeable (RGP) contact lenses. Research was led by the Universidad Autónoma de Aguascalientes, México and Fundación Universitaria del Área Andina Pereira, Colombia. Methods: A single center, prospective non-randomized, comparative, interventional, open-label study, in which the differences in binocular vision performance with both spectacles and RGP contact lenses was carried out from December 2018 to December 2019. Sampling was performed according to consecutive cases with keratoconus that met the inclusion criteria until the proposed sample size was reached. Results: Rigid gas-permeable (RGP) contact lenses notably enhanced distance and near visual acuity in keratoconus patients compared to spectacles. Visual alignment analysis shows exophoria at both distances and is slightly higher with RGP contact lenses. The difference was statistically significant (p<0.05), with 82.5 % presenting compensated phoria with spectacles and pnly 42.50% with RGP contact lenses. Stereoscopic vision improved while wearing RGP contact lenses (42.59 %), although accommodation and accommodative flexibility remained within normal ranges. Conclusions: Patients with keratoconus fitted with RGP contact lenses have improved binocular vision skills such as visual acuity, stereopsis, and accommodative flexibility. However, even when the vergence and motor system is decompensated with respect to normal ranges, the range between break and recovery points for both fusional reserves and the near point of convergence (NPC) improves with the use of RGP contact lenses, giving indications of an adaptive condition of the motor system from the medium to the long term.(AU)

Evaluation of 3D tablet-based stereoacuity test ASTEROID in children with normal and abnormal visual acuity.

PURPOSE: To assess the utility of 3D, tablet-based, glasses-free Accurate STEReotest (ASTEROID) in children compared with the Titmus test. METHODS: Children aged 5-13 years were enrolled in a single-center, nonrandomized, observational comparison study and analyzed by age (5-7 vs 8-13 years) and visual acuity (20/25 or better in both eyes vs abnormal). Each participant underwent both the ASTEROID and Titmus stereoacuity tests. Stereoacuity was defined as fine (≤60 arcsec), moderate (61-200 arcsec), coarse (201-1199 arcsec), or very coarse to nil (≥1200 arcsec). Agreement between the tests was assessed using a weighted kappa (κ) statistic based on all four categories. RESULTS: A total of 112 children were included: 28 aged 5-7 with normal visual acuity, 30 aged 5-7 with abnormal visual acuity, 34 aged 8-13 with normal visual acuity, and 20 aged 8-13 with abnormal visual acuity. Mean ASTEROID score was 688 ± 533 arcsec (range, 13-1200 arcsec). Agreement between ASTEROID and Titmus test scores for participants overall was moderate (κ = 0.52). By subgroup, agreement was fair for children 5-7 with abnormal visual acuity (κ = 0.31), moderate for children 5-7 with normal visual acuity (κ = 0.47) and children 8-13 with normal visual acuity (κ = 0.42), and substantial for children 8-13 with abnormal visual acuity (κ = 0.76). Where ASTEROID and Titmus score group varied, ASTEROID score was poorer in 94% (47/50) of cases. CONCLUSIONS: ASTEROID is a digital, tablet-based test that evaluates global stereopsis, does not require glasses, and provides a continuum of scores. Among children, ASTEROID has good agreement with the Titmus test; however, it may be more sensitive at detecting stereovision deficits. Further study is necessary to determine which test is more accurate.

[Understanding and reflection on the prevention and control of pre-myopia in children].

The International Myopia Institute introduced the concept of "pre-myopia" in 2019, defining it as children with refractive error ≤+0.75 D and >-0.50 D. By considering baseline refractive error, age, and other quantifiable risk factors, there is a significant likelihood that individuals falling into this category may develop myopia in the future. Therefore, it is deemed worthwhile to implement preventative intervention measures.This article delves into the epidemiology of premyopia in children and adolescents, the criteria for determining pre-myopia, the characteristics of refractive changes, and the existing evidence gaps in pre-myopia control technology. Furthermore, it explores the role and advantages of implementing pre-myopia control to enhance efforts in preventing and managing myopia. The paper highlights the essential value and future trajectory of pre-myopia control in the comprehensive management of myopia. The ultimate goal is to foster collaboration with professionals, aiming to discuss innovative strategies for effectively preventing and managing the onset and progression of myopia.

Scotopic and Photopic Conventional Visual Acuity and Hyperacuity - Binocular Summation.

Purpose: The purpose of this study was to determine and compare binocular summation (BiS) of conventional visual acuity (cVA) versus hyperacuity (hVA) for photopic and scotopic luminance conditions as a potential biomarker to assess the outcome of interventions on binocular function. Methods: Sixteen young adults (age range [years] = 21-31; 8 women; cVA logMAR < 0.0) participated in this study. The Freiburg Visual Acuity Test (FrACT) was used for VA testing and retested on another day. Both cVA and hVA were determined for dark grey optotypes on light grey background. Participants underwent 40 minutes of dark adaptation prior to scotopic VA testing. Binocular and monocular VA testing was performed. The eye with better VA over the 2 days of testing was selected, the BiS was quantified (binocular VA - better monocular VA) and repeated measures ANOVAs were performed. Results: Binocular VA exceeded monocular VA for all luminance conditions, VA-types, and sessions. We report BiS estimates for photopic and scotopic cVA and hVA, (logMAR BiS ± SEM [decimal BiS]): photopic = -0.01 ± 0.01 [1.03] and -0.06 ± 0.03 [1.15]; and scotopic = -0.05 ± 0.01 [1.12] and -0.11 ± 0.04 [1.28], respectively). Improvement for binocular vision estimates ranged from 0.01 to 0.11 logMAR. A repeated-measures ANOVA (RM ANOVA) did not reveal significant effects of LUMINANCE or VA TYPE on BiS, albeit a trend for strongest BiS for scotopic hVA (15% vs. 28%, photopic versus scotopic, respectively) and weakest for photopic cVA (3% vs. 12%, photopic versus scotopic conditions, respectively). Conclusions: Our results indicate that BiS of VA is relevant to scotopic and photopic hVA and cVA. It appears therefore a plausible candidate biomarker to assess the outcome of retinal therapies restoring rod or cone function on binocular vision. Translational Relevance: Binocular summation of visual acuity might serve as a clinical biomarker to monitor therapy outcome on binocular rod and cone-mediated vision.

Efficacy and adverse reactions of peripheral add multifocal soft contact lenses in childhood myopia: a meta-analysis.

OBJECTIVES: This study aims to compare the efficacy of peripheral add multifocal soft contact lenses (SCLs) (excluding bifocal SCLs) with single vision contact lenses or spectacles in controlling myopia progression. METHOD: A comprehensive literature search was conducted in the Pubmed, EMBASE, Web of Science, and Cochrane Library databases until October 2023. The literature was thoroughly screened based on predetermined eligibility criteria. Pooled odds ratios (ORs) were calculated for dichotomous data and weighted mean differences (WMD) for continuous data. RESULTS: A total of 11 articles comprising 787 participants were included in this meta-analysis. Our pooled results demonstrated that the peripheral add multifocal SCLs groups exhibited significantly reduced refraction progression (MD = 0.20; 95%CI, 0.14 ∼ 0.27; P<0.001) and less axial length elongation (MD=-0.08; 95%CI, -0.09∼-0.08; P<0.001) compared to the control group. There was no significant difference in high-contrast logMAR distance visual acuity between the two groups (MD = 0.01; 95%CI, -0.00 ∼ 0.02; P = 0.19). However, the group using single-vision lenses had better low-contrast logMAR distance visual acuity compared to those using peripheral add multifocal SCLs (MD = 0.06; 95%CI, 0.02 ∼ 0.10; P = 0.004). Data synthesis using a random-effects model indicated an incidence of contact lens-related adverse events of 0.065 (95%CI, 0.048 ∼ 0.083). CONCLUSIONS: The present meta-analysis signifies that peripheral defocus modifying contact lenses are effective in slowing down the progression of myopia and reducing axial elongation.

Evaluation of objective and subjective binocular ocular refraction with looking in type.

BACKGROUND: This study aimed to compare the results of the Chronos binocular/monocular refraction system, that measures objective and subjective ocular refraction in one unit, to objective findings obtained from a conventional autorefractometer and a conventional subjective ocular refraction using a trial-frame in real space. METHODS: Twenty-eight healthy volunteers (21.2 ± 1.5 years old) were included in this study. Objective ocular refraction was measured using two tests: the Chronos binocular/monocular refraction system under binocular conditions and a conventional autorefractometer under monocular conditions. Subjective ocular refraction was measured using three tests: Chronos binocular/monocular refraction system under binocular, monocular conditions, and trial-frame in the real space under monocular conditions. The measurement distance was set to 5.0 m for each test. All ocular refractions were converted into spherical equivalents (SEs). RESULTS: The objective SE was significantly more negative with Chronos binocular/monocular refraction system under binocular condition (- 4.08 ± 2.76 D) than with the conventional autorefractometer under monocular condition (- 3.85 ± 2.66 D) (P = 0.002). Although, the subjective SE was significantly more negative with Chronos binocular/monocular refraction system under binocular condition (- 3.55 ± 2.67 D) than with the trial-frame in the real space under monocular condition (- 3.33 ± 2.75 D) (P = 0.002), Chronos binocular/monocular refraction system under monocular condition (- 3.17 ± 2.57 D) was not significantly different from that in trial-frame in real space under monocular condition (P = 0.33). CONCLUSION: These findings suggest that the Chronos binocular/monocular refraction system, which can complete both objective and subjective ocular refraction tests in a single unit, is suitable for screening ocular refraction, although it produces slightly more myopic results. Furthermore, subjective ocular refraction testing accuracy in Chronos binocular/monocular refraction system can be equivalent to trial-frame in real-space testing by switching from binocular to monocular condition.

Peripheral Refraction Using Ancillary Retinoscope Component (P-ARC).

Purpose: To assess the agreement of retinoscope-based peripheral refraction techniques with the criterion standard open-field autorefractor. Methods: Fifty young adults (mean age, 24 ± 3 years) participated in this study. Two masked, experienced senior examiners carried out central refraction and peripheral refraction at the temporal 22° (T22°) and nasal 22° (N22°) eccentricities. Peripheral refraction techniques were (a) peripheral refraction using ancillary retinoscope component (P-ARC), (b) retinoscopy with eye rotation, and (c) open-field autorefractor. Peripheral refraction with retinoscopy values was compared with an open-field autorefractor (Shinn Nippon NVision-K) to assess the agreement. All measurements were taken from the right eye under noncycloplegic conditions. Results: The mean difference ±95% limits of agreement of peripheral refraction values obtained using P-ARC from T22° (+0.11 diopters [D] ± 1.20 D; P = 0.20) or N22° (+0.13 D ± 1.16 D; P = 0.13) were comparable with open-field autorefractor. The eye rotation technique compared to autorefractor showed a significant difference for T22° (+0.30 D ± 1.26 D; P = 0.002); however, there was an agreement for N22° (+0.14 D ± 1.16 D; P = 0.10). With respect to the identification of peripheral refraction patterns, examiners were able to identify relative peripheral hyperopia in most of the participants (77%). Conclusions: Peripheral refraction with P-ARC was comparable with open-field autorefractor at T22° and N22° eccentricities. Peripheral retinoscopy techniques can be another approache for estimating and identifying peripheral refraction and its patterns in a regular clinical setting. Translational Relevance: Retinoscope with P-ARC has high potential to guide and enable eye care practitioners to perform peripheral refraction and identify peripheral refraction patterns for effective myopia management.

Converting LEA to Pelli-Robson contrast sensitivity score in neuro-ophthalmology patients.

PURPOSE: The Pelli-Robson and LEA contrast sensitivity charts are commonly used in clinical settings to measure contrast sensitivity. Although the Pelli-Robson chart is considered the gold standard, it is limited by its bulky size. The LEA chart, on the contrary, offers a more practical and portable option that is still reliable. This has led to questions about whether we can predict Pelli-Robson scores based on LEA scores. This study developed a conversion method to help transition from the LEA chart to the Pelli-Robson chart and validate the conversion score. METHODS: In this retrospective study, we analyzed the relationship between LEA and the Pelli-Robson contrast sensitivity test. Our study examined a total of 120 eyes. We developed a conversion table through the equipercentile equating method. Subsequently, we assessed the reliability and accuracy of this algorithm for converting LEA results into Pelli-Robson contrast sensitivity scores. RESULTS: The study used a conversion table to convert LEA scores to Pelli-Robson scores. The conversion table achieved a reliability of 0.91 based on intraclass correlation, and the algorithm had an accuracy of 81.6% within a 1-point difference from the raw score. CONCLUSIONS: This study reported a reliable and comparable conversion algorithm for transforming LEA scores into converted estimated Pelli-Robson scores, thereby improving the usefulness of existing data in both clinical and research contexts.

Comparison of simultaneous prism and cover test (SPCT) and prism and alternate cover test (PACT) measurements with final power of Press-On prism power dispensed.

PURPOSE: To investigate the association of strabismic angle obtained by simultaneous prism and cover test (SPCT) and prism alternate cover test (PACT) with the final power of Press-On prism used in adults with symptomatic strabismus. METHODS: The medical records of consecutive patients seen by a single orthoptist at an urban, tertiary care hospital over a 36-month period were reviewed retrospectively. All subjects had been prescribed Press-On prism for diplopia after evaluation with SPCT and PACT measurements at distance fixation. Prism dispensed was chosen by the patient using a trial Press-On prism set. RESULTS: A total of 244 charts were reviewed. Of these, 108 adult patients had prism dispensed, and 32 had both SPCT and PACT measurements. Mean SPCT measurement was 7Δ (median, 6Δ; range, 3Δ-14Δ); mean PACT, 13Δ (median, 11Δ; range, 8Δ-20Δ). The mean prism power dispensed was 7Δ (median, 6Δ; range, 1Δ-15Δ); this was not significantly different from mean SPCT (P = 0.35). There was a large difference (6Δ) between mean PACT measurements and mean prism dispensed (P < 0.001). At follow-up of 1 year, 21 patients (66%) remained in prism. Nine patients (4%) elected to undergo eye muscle surgery, 7 with horizontal strabismus, 6 of whom had SPCT measurements of >10Δ and PACT measurements of >15Δ. CONCLUSIONS: Press-On prism power used was more closely tied to the angle of strabismus obtained by SPCT. Overall success rate of Press-On prism was good when the prism power dispensed was close to the SPCT measurement, suggesting that it is reasonable to initiate treatment with a weaker prism, approximating the SPCT measurement, building up only if there are continuing symptoms.

Agreement in non-cycloplegic and cycloplegic refraction between a photoscreener and a calibrated autorefractor.

INTRODUCTION: Photoscreeners have been shown to provide excellent measurements of the refractive error. However, whether they could be used for assessing cycloplegic refraction has not been examied. This study aimed to evaluate the agreement between cycloplegic and non-cycloplegic measurements obtained using a photoscreener and stationary autorefractor, respectively. METHODS: This study included all patients undergoing routine ophthalmic examination at the Hygeia Clinic (Poland) from June to July 2022. Each patient underwent non-cycloplegic and cycloplegic refraction assessments using the 2WIN photoscreener (Adaptica SRL, Padova, Italy) and an ARK-1 stationary autorefractor ARK-1 (Nidek Co Ltd., Tokyo, Japan), respectively. Each pair of assessments was conducted in random order, and all values were determined at a vertical distance of 12 mm. The agreement between cycloplegic and non-cycloplegic measurements was assessed using paired t-tests, Bland-Altman and ABCD ellipsoids. RESULTS: This analysis included 82 patients, of which 52 were female. Their mean age was 34.39 ± 13.13 years. The non-cycloplegic spherical equivalent (SE) did not differ significantly between the 2WIN (- 1.22 ± 2.45) and ARK-1 (- 1.19 ± 2.96) devices (p = 0.580). However, the cycloplegic SE values demonstrated more negative values with the 2WIN device (- 1.13 ± 2.19) than with the ARK-1 device (- 0.75 ± 3.03; p = 0.007). The non-cycloplegic and cycloplegic measurements were strongly correlated between the devices (r = 0.9473 and 0.9411, respectively). However, the correlation between their cycloplegic shifts in SE was low (r = 0.2645). Ellipsoid refraction aligned better non-cycloplegic (ARK-1 = 1.00; 2WIN = 1.74) than with cycloplegic refraction (ARK-1 = 1.43; 2WIN = 1.90). CONCLUSION: While the cycloplegic measurements obtained with the 2WIN photoscreener were strongly correlated with those obtained with the ARK-1 stationary autorefractor for most of the analyzed parameters, they should not be considered interchangeable.

Korean version of the MNREAD acuity chart.

To investigate the efficacy of the Korean version of the Minnesota low vision reading chart. A Korean version consisting of 38 items was prepared based on the MNREAD acuity chart developed by the University of Minnesota. A linguist composed the representative sentences, each containing nine words from second and third grade levels of elementary school. Reading ability was measured for 20-35-year-old subjects with normal visual acuity (corrected visual acuity of logMAR 0.0 or better). The maximum reading speed (words per minute [wpm]) for healthy participants, reading acuity (smallest detectable font size), and critical print size (smallest font size without reduction of reading speed) were analyzed. The average age of the subjects was 28.3 ± 2.6 years (male:female ratio, 4:16). The average reading time for 38 sentences was 3.66 ± 0.69 s, with no differences in the average maximum reading speed between sentences (p = 0.836). The maximum reading speed was 174.2 ± 29.3 and 175.4 ± 27.8 in the right and left eye, respectively. Reading acuity was measured as logMAR 0.0 or better in 80% of the cases. All subjects showed a critical print size of 0.2 logMAR or better. The overall reading ability can be measured using the Korean version of the MNREAD acuity chart, thereby making it useful in measuring the reading ability of those with Korean as their native language.

The Freiburg Acuity Test in Preschool Children: Testability, Test-Retest Variability, and Comparison With LEA Symbols.

Purpose: To determine the testability, performance, and test-retest variability (TRV) of visual acuity (VA) assessment using the Freiburg Visual Acuity Test (FrACT) compared to the LEA Symbols Test (LEA) in preschool children. Methods: In 134 preschool children aged 3.0 to 6.8 years, monocular VA of each eye was measured twice with a four-orientation Landolt C version of the FrACT and once with the LEA. FrACT runs were preceded by a binocular run for explanatory purposes. Test order alternated between subjects. Optotypes were presented on a computer monitor (FrACT) or on cards (LEA) at a distance of 3 m. Results: Overall, 68% completed the FrACT (91/134 children) and 88% completed the LEA (118/134 children). Testability depended on age: FrACT, 19% (<4 years) and 87% (≥4 years); LEA, 70% (<4 years) and 95% (≥4 years). Mean ± SD VA difference between tests was 0.11 ± 0.19 logarithm of the minimum angle of resolution [logMAR], with LEA reporting better acuity. The difference depended on age (0.27 ± 0.23 logMAR [<4 years], 0.09 ± 0.18 logMAR [≥4 years], P < 0.001) and on test sequence (higher age dependence of FrACT VAs for LEA first, P < 0.001). The 95% limits of agreement for the FrACT TRV were ±0.298 logMAR. Conclusions: The examiner-independent FrACT, using international reference Landolt C optotypes, can be used to assess VA in preschool children aged ≥4 years, with reliability comparable to other pediatric VA tests. Translational Relevance: Use of the automated FrACT for VA assessment in preschool children may benefit objectivity and validity as it is a computerized test and employs the international reference Landolt C optotype.

Correlation analysis of angles κ and α with the refraction and anterior segment parameters in children.

AIM: To investigate the correlation of angles α and κ with the refractive and biological parameters in children. METHODS: This case-series study included 438 eyes of 219 children (males/females = 105/114, age: 3-15 years). Ocular biometric parameters, including axial length, corneal radius of curvature (CR), white-to-white distance (WTW), angle κ and angle α, were measured using IOL Master 700; auto-refraction were assessed under cycloplegia. The eyes were assigned to different groups based on CR, WTW, and gender to compare the angles α and κ, and analyze the correlations between the differences of biological parameters on angles α and κ. RESULTS: The means of axial length, CR, WTW, angle α, and angle κ were 23.24 ± 1.14 mm, 7.79 ± 0.27 mm, 11.68 ± 0.41 mm, 0.45 ± 0.25 mm, and 0.27 ± 0.22 mm, respectively. Angle α was correlated with CR and WTW (fixed effect coefficient [FEC] = 0.237, p = 0.015; FEC = -0.109, p = 0.003; respectively), and angle κ also correlated with CR and WTW (FEC = 0.271, p = 0.003; FEC = -0.147, p < 0.001, respectively). Comparing subgroups, the large CR and small WTW group had larger angles α (0.49 ± 0.27 vs. 0.41 ± 0.21, p < 0.001; 0.46 ± 0.27 vs. 0.44 ± 0.21, p < 0.05, respectively) and κ (0.29 ± 0.25 vs. 0.24 ± 0.15, p < 0.01; 0.29 ± 0.25 vs. 0.26 ± 0.19, p < 0.05, respectively). The differences in interocular angles α and κ showed correlation with interocular WTW (r = - 0.255, p < 0.001; r = - 0.385, p < 0.001). Eyes with smaller WTW tended to have larger angle κ (0.28 ± 0.27 vs. 0.25 ± 0.15, p < 0.05). CONCLUSION: The size of angle α/κ may be correlated to CR and WTW, and a larger WTW eye may suggest a smaller angle κ compared with the fellow eye.

Evaluating distance stereoacuity in children 4-17 years of age with a novel digital application.

Distance stereoacuity measurement enables the evaluation and management of binocular vision disorders. Here, we compare the results obtained using standard tests for distance stereoacuity measurement with the novel STab test. We tested 87 children (4-17 years of age) using different tests for the quantification of stereopsis at distance: Distance Randot Stereotest (DRS), M&S random dots (M&S), and STab. A strong correlation was demonstrated between M&S-DRS (0.8), M&S-STab (0.81), DRS-STab (0.85) (all P < 0.0001). The limit of agreement between M&S and DRS was 0.45; between M&S and STab, 0.47; and between DRS and STab, 0.38. Our results suggest that all three methods can be used interchangeably.