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To determine whether a newly modified capsular tension ring (CTR) is effective at preventing toric intraocular lens (TIOL) rotation and misalignment.John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.Experimental study.Ten human cadaver eyes were used to test the ease or difficulty of TIOL rotation in the capsular bag under 3 experimental conditions: a TIOL alone, a TIOL with a standard CTR, or a TIOL with a newly modified CTR with indentations in a sinusoidal pattern. Scores for the ease of IOL rotation were compared by using the nonparametric Friedman analysis of variance test. In addition, both anterior and posterior Miyake-Apple views were filmed to observe the rotational stability of TIOLs in the capsular bag under the 3 test conditions.In the ten eyes of five patients, the rotational stability improved with a standard CTR, but further improvement was statistically observed (P.05) with the newly modified CTR under all test conditions. This was true for both IOLs used (AcrySof and TECNIS toric IOLs), with or without ophthalmic viscosurgical device, and for either clockwise or counterclockwise rotations.A newly designed CTR prototype represents a new technology for improving the rotational stability of a TIOL in the capsular bag. Under all test conditions, the prototype performed significantly better than a standard CTR. The results support the use of this new CTR design to improve the accuracy and refractive success of TIOLs.

BackgroundDriving is a visually intensive task. In Cameroon, where the burden of road traffic deaths is high, visual assessment is not universally performed before the issuance of driver licenses. This study aims to assess the visual status of commercial drivers (CDs) in the southwestern region of Cameroon, and to find its relation to road traffic crashes (RTCs).MethodsThis work was a cross-sectional community-based study on CDs in Limbe and Buea. Questionnaires were used to assess sociodemographic parameters, the incidence of RTCs, and self-reported visual status. Visual acuity (VA) was measured using a standard Snellen chart at 6 m. Statistical analysis was performed using descriptive methods: frequencies, the paired Student’s t-test, and the chi-square test.ResultsTwo hundred seven CDs were enrolled in this study, all of which were male, with a mean age of 41.8 ± 12.1 years. A total of 15.0% had undergone an eye exam prior to licensure, and 3.4% had undergone an eye exam within the past 10 years. The VA in the better-seeing eye of participants was less than 6/9 and 6/12 in 14.1 and 10.6% of CDs, respectively. Seventy-five percent of CDs with self-reported poor vision and 95% of CDs with VA p p ConclusionsA large proportion of CDs did not undergo a visual assessment before the issuance or renewal of their driver licenses. A substantial number of CDs had poor vision in their better-seeing eye and suffered from RTCs and related injuries, which suggests that the visual status of CDs in Cameroon is related to the gruesome number of road traffic crashes and deaths in the country. Therefore, concerned authorities should consider making vision tests a necessary requirement for the obtention of driver licenses.

SIGNIFICANCE This review summarizes the main factors of refractive error after silicone oil removal combined with cataract surgery.The post-operative refractive results of silicone oil removal combined with cataract surgery are closely related to the patient's future vision quality. This report summarizes the factors that influence the difference between the actual post-operative refractive power and the pre-operatively predicted refractive power after silicone oil removal combined with cataract surgery, including axial length, anterior chamber depth, silicone oil, commonly used tools for measuring intraocular lens power, and intraocular lens power calculation formulas, among others. The aim of the report is to assist clinical and scientific research on the elimination of refractive error after silicone oil removal combined with cataract surgery.

To clarify the changing characteristics of choroidal thickness over time within different age ranges and among different refractive statuses of children aged 6 to 18 years.Prospective cohort study.Data of axial length, cycloplegic refraction, and choroidal thickness (using swept-source optical coherence tomography) were collected at baseline and at a 1-year follow-up for 756 participants. One-year change in choroidal thickness and its association with age and refraction were analyzed.Significantly greater attenuation of choroidal thickness was observed in younger children aged 6-9 years for all participants (-9 ± 25 μm) and for those with a myopic shift (-12 ± 25 μm), whereas there was a larger increase in adolescents aged 10-13 years for those without a myopic shift (9 ± 23 μm). There was a marked decrease in the choroidal thickness for newly developed myopic patients compared with persistent-nonmyopic patients and persistent-myopic patients (P.01). The association between changes in axial length and choroidal thickness was less strong in persistent-myopic patients (β = -15.4, P = .022) than that in persistent-nonmyopic patients (β = -30.4, P.001) and newly developed myopic patients (β = -33.7, P = .001), whereas among the persistent-myopic patients, the association was less strong in the baseline mild-myopic patients (β = -10.4, P = .193) than that in the baseline moderate-to high-myopic patients (β = -31.4, P = .026).Changes in choroidal thickness varied by age. There was an increased rapid thinning of the choroid among newly developed myopic patients, and a nonsignificant association between changes in choroidal thickness and axial length in the early stages of myopia.

We evaluated surgical outcomes of bilateral rectus (BLR) recession in patients with intermittent exotropia who underwent diagnostic monocular occlusion. Records of patients with intermittent exotropia who were preoperatively examined one-hour monocular occlusion and underwent BLR recession were reviewed retrospectively. Patients were classified into two groups based on change in exodeviation angle: responders (≥5 change in prism diopters [PD] after occlusion) or non-responders (

WE sought to evaluate differences in effective lens position (ELP) based on the lens design. Intraocular lenses (IOLs) with plate-haptic, c-loop haptic, and a rhexis-fixated lens were compared.Retrospective, multicenter, comparative case series.The study included patients having age-related cataract surgery with implantation of either a plate-haptic, c-loop haptic, or a novel rhexis-fixated IOL. Biometry and refraction measurements were conducted preoperatively and 3 months postoperatively. Lens constant optimization was performed.Seventy eyes of 56 subjects were included. ELP for rhexis-fixated IOL was shortest (4.29 ± 0.24 mm), followed by c-loop haptic (4.41 ± 0.42 mm) and plate-haptic (4.51 ± 0.26 mm) IOL. Difference in ELP was significant between rhexis-fixated IOL and both plate-haptic (P = .001) and c-loop haptic IOL (P = .000). Anterior chamber depth adjustment based on lens design showed a significant effect on refraction and IOL power predictions for all formulas and lenses (P.05). For the rhexis-fixated IOL the differences in refraction ranged from -0.039 diopters (D) for the Hill-Radial Basis Function to -0.096 D for Haigis. The other 2 lenses showed mean differences in refraction between +0.046 D for Hill-Radial Basis Function and +0.097 D for Haigis.The difference in IOL fixation and its resulting position in the capsular bag have a significant effect on the effective lens position and consequently a significant effect on the prediction of postoperative refraction.

To evaluate outcomes of bilateral cataract surgery in infants 1 to 7 months of age performed by Infant Aphakia Treatment Study (IATS) investigators during IATS recruitment and to compare them with IATS unilateral outcomes.Retrospective case series review at 10 IATS sites.The Toddler Aphakia and Pseudophakia Study (TAPS) is a registry of children treated by surgeons who participated in the IATS.Children underwent bilateral cataract surgery with or without intraocular lens (IOL) placement during IATS enrollment years 2004 through 2010.Visual acuity (VA), strabismus, adverse events (AEs), and reoperations.One hundred seventy-eight eyes (96 children) were identified with a median age of 2.5 months (range, 1-7 months) at the time of cataract surgery. Forty-two eyes (24%) received primary IOL implantation. Median VA of the better-seeing eye at final study visit closest to 5 years of age with optotype VA testing was 0.35 logarithm of the minimum angle of resolution (logMAR; optotype equivalent, 20/45; range, 0.00-1.18 logMAR) in both aphakic and pseudophakic children. Corrected VA was excellent (20/40) in 29% of better-seeing eyes, 15% of worse-seeing eyes. One percent showed poor acuity (≥20/200) in the better-seeing eye, 12% in the worse-seeing eye. Younger age at surgery and smaller (9.5 mm) corneal diameter at surgery conferred an increased risk for glaucoma or glaucoma suspect designation (younger age: odds ratio [OR], 1.44; P = 0.037; and smaller cornea: OR, 3.95; P = 0.045). Adverse events also were associated with these 2 variables on multivariate analysis (younger age: OR, 1.36; P = 0.023; and smaller cornea: OR, 4.78; P = 0.057). Visual axis opacification was more common in pseudophakic (32%) than aphakic (8%) eyes (P = 0.009). Unplanned intraocular reoperation occurred in 28% of first enrolled eyes (including glaucoma surgery in 10%).Visual acuity after bilateral cataract surgery in infants younger than 7 months is good, despite frequent systemic and ocular comorbidities. Although aphakia management did not affect VA outcome or AE incidence, IOL placement increased the risk of visual axis opacification. Adverse events and glaucoma correlated with a younger age at surgery and glaucoma correlated with the presence of microcornea.

Purpose The use of monochromatic light in the assessment of intraocular lenses (IOLs) has been criticized for not representing the real-world situation. This study aimed to measure and compare the image quality of 3 extended depth-of-focus (EDOF) IOL models in monochromatic and polychromatic light. Setting David J Apple Laboratory, Heidelberg, Germany. Design In vitro study. Methods An optical metrology instrument was used to study image quality metrics of diffractive IOLs with chromatic aberration correction (Symfony and AT Lara) and a refractive lens (Mini Well). The modulation transfer function (MTF) was measured in green and polychromatic light at a 2.0 mm, 3.0 mm, and 4.0 mm aperture. The EDOF IOL's tolerance to defocus was tested against a monofocal lens. Results The mean MTF of the EDOF IOL at far distance was decreased in polychromatic compared with monochromatic light. The largest effect was found in the refractive lens; however, at intermediate distance, only small differences occurred. In their tolerance to defocus, the EDOF IOLs were superior to the monofocal IOL. The diffractive IOL had higher MTFs than that of the refractive IOL at 2 primary foci, the refractive IOL's optical quality varied less with defocus at 3.0 mm. The refractive lens was the most susceptible to changes in aperture size. Conclusion The diffractive EDOF IOL was more resistant to chromatic effects than the refractive IOL. The EDOF IOLs provided an extended through-focus performance compared with the monofocal IOL, but differences in optical design, particularly pupil dependency, should be considered when refining IOL selection for patients.

Purpose: To study the incidence and progression of refractive errors in medical students. Methods: This is a retrospective study including 200 medical students of our college during the period of July 2015 to June 2018. Examination included visual acuity testing using Snellens chart, slit lamp biomicroscopy, fund us examination with direct ophthalmoscope, indirect ophthalmoscope and refraction. Students were examined for refractive errors and findings compared with pre-admission data. Changes in spherical, cylindrical power analysed. Results: Prevalence of Myopia increased from 40% to 48%. Incidence of new refractive errors in emmetropes was 8%. Myopic change found was -0.75D to -1.0D. Conclusion: Students in medical colleges have high prevalence of myopia, high incidence of adult onset myopia and statistically significant progression. Parental history, prolonged eye strain, excessive use of electronic gadgets, decreased outdoor activity and urban background had significant association with prevalence of myopia.

Purpose Incorporating mass pediatric vision screening programs as part of a national agenda can be challenging. This review assessed the implementation strategy of the existing pediatric vision screening program. Methods A search was performed on PubMed, EBSCO host MEDLINE Complete, and Scopus databases encompassing the past ten years for mass pediatric screening practice patterns that met the selection criteria regarding their objectives and implementation. Results were analyzed from 18 countries across five continents. Results Eight countries (44%) offered screening for distance visual acuity only, where the majority of the countries (88%) used either Snellen or Tumbling E chart. High-income countries initiated screening earlier and applied a more comprehensive approach, targeting conditions other than reduced vision only, compared with middle-income countries. Chart-based testing was most commonly performed, with only three countries incorporating an instrument-based approach. Lack of eyecare and healthcare practitioners frequently necessitated the involvement of non-eyecare personnel (94%) as a vision screener including parent, trained staff, and nurse. Conclusions Implementation of a vision screening program was diverse within countries preceded by limited resources issues. Lack of professional eyecare practitioners implied the need to engage a lay screener. The limitation of existing tests to detect a broader range of visual problems at affordable cost advocated the urgent need for the development of an inexpensive and comprehensive screening tool.

Purpose Current chart-based tests of spatial contrast sensitivity (SCS) with fixed or narrow frequency ranges (≤18 cycles/°) cannot characterise the limits of spatial contrast vision. Here we present the design and validation of a chart-based measure of the spatial contrast envelope. Methods Following the principles of the standard visual acuity (Bailey-Lovie) and contrast sensitivity (Pelli-Robson) charts, a combined spatial-contrast and visual acuity chart was designed using a language-independent triangular symbol for a four-alternative forced-choice procedure plus chart rotation. Symbol frequencies ranged between 0.38 and 60 cycles/° spaced along 10 radial axes (0.55%-100% contrast). The chart was validated with reference to the Bailey-Lovie and Pelli-Robson charts; its reliability and sensitivity to changes in illumination, simulated cataract and blur was evaluated in healthy adults. Results The photopic SCS function could be measured in 5.5 ± 0.5 min; thresholding around the spatial contrast resolution limit reduced completion times to ~2 min. There was good agreement with high-contrast visual acuity (difference = 0.08 ± 0.02 logMAR) and contrast-sensitivity at 1.5 cycles/° (0.13 ± 0.06 logCS). Test-retest reliability was excellent at all spatial frequencies (ICC = 0.99). Mesopic illumination or simulated cataract caused a generalised SCS loss; myopic blur reduced high-frequency sensitivity. Spatial contrast sensitivity was independent of radial axis orientation (cardinal or oblique). Conclusions The chart provides a time-efficient, reliable and inexpensive measure of SCS with applications in research and clinic for detecting subtle deficits in early stages of ocular and neurological conditions that often manifest at higher frequencies. It is sensitive to vision changes occurring in dim lighting and with simulated cataract and blur. The chart is available open-access for self-printing; contrast variation in print can be controlled through user calibration and/or establishing normative SCS functions using the theoretical values.

Purpose: To provide guidance on the frequency and components of eye examinations for healthy children aged 0 to 5 years. Methods: These guidelines were developed based on the medical literature and clinical experience of an expert committee. PubMed/Medline searches were performed, with selected publications not restricted to systematic reviews, randomized controlled trials, or observational studies. The Grading of Recommendations Assessment, Development, and Evaluation profile was applied when suitable, and for issues without scientific evidence, recommendations were based on expert consensus. Recommendations by the American Academy of Pediatrics, American Association of Pediatric Ophthalmology and Strabismus, American Academy of Ophthalmology, Royal College of Ophthalmologists, and Canadian Ophthalmological Society were also reviewed. The final guideline document was approved by the Brazilian Pediatric Ophthalmology Society and by the Brazilian Pediatric Society. Results: Newborns must undergo the red reflex test and inspection of the eyes and adnexa by a pediatrician within 72 hours of life. The red reflex test should be repeated by the pediatrician during childcare consultations at least three times per year during the first 3 years of life. If feasible, a comprehensive ophthalmologic examination may be performed between 6 and 12 months of age. Until 36 months of age, the pediatrician should assess the infant’s visual development milestones, age-appropriate assessment of visual function, ocular fixation, and eye alignment. At least one comprehensive ophthalmologic examination should be performed at 3 to 5 years of age. The examination should minimally include inspection of the eyes and adnexa, age-appropriate visual function assessment, evaluations of ocular motility and alignment (cover tests), cycloplegic refraction, and dilated fundus. Conclusions: Guidelines concerning the frequency of ophthalmic assessment are important tools for directing physicians regarding best practices that avoid treatable vision problems that affect children’s development, school, and social performance and cause unnecessary permanent vision loss. RESUMO Objetivo: Fornecer orientações sobre a frequência e os componentes dos exames oftalmológicos para crianças saudáveis de 0 a 5 anos. Métodos: Essas diretrizes foram desenvolvidas com base em revisão bibliográfica e experiência clínica de um comitê de especialistas. Foram realizadas buscas PubMed/Medline; documentos selecionados não se restringiram a revisões sistemáticas, ensaios clínicos randomizados e estudos observacionais. Quando adequado, o perfil GRADE foi aplicado para graduá-los e o consenso de especialistas foi usado nos tópicos sem evidência científica. Também foram revisadas as recomendações pela Academia Americana de Pediatria, Associação Americana de Oftalmologia Pediátrica e Estrabismo, Academia Americana de Oftalmologia, Royal College of Ophthalmologist e Sociedade Canadense de Oftalmologia. O documento final foi aprovado pela Sociedade Brasileira de Oftalmologia Pediátrica e Sociedade Brasileira de Pediatria. Resultados: Os recém-nascidos devem ser submetidos ao teste do reflexo vermelho e inspeção dos olhos e anexos pelo pediatra dentro de 72 horas de vida ou antes da alta da maternidade. O teste do reflexo vermelho deve ser repetido pelo pediatra durante as consultas de puericultura pelo menos três vezes ao ano durante os primeiros 3 anos de vida. Se factível, um exame oftalmológico completo pode ser feito entre 6 a 12 meses de vida. Até os 36 meses de idade, os marcos visuais, função visual apropriada para a idade, fixação e alinhamento ocular também devem ser avaliados pelo pediatra ou médico da família. Pelo menos um exame oftalmológico completo deve ser realizados entre 3 e 5 anos de idade. O exame deve conter pelo menos inspeção dos olhos e anexos, avaliação da função visual apropriada para a idade, avaliação da motilidade e alinhamento ocular (testes de cobertura), refração sob cicloplegia e avaliação do fundo de olho dilatado. Conclusões: As diretrizes sobre a frequência da avaliação oftalmológica são ferramentas importantes para orientar os médicos sobre a melhor prática a fim de evitar problemas visuais tratáveis na infância, que poderiam comprometer seu desenvolvimento social, escolar e global, além de causar perda permanente da visão.

Supplemental digital content is available in the text., SIGNIFICANCE Evidence supporting the contributions of near work in myopia is equivocal. Findings from this pilot study suggest that a high prevalence of myopia in ultra-Orthodox boys may be attributed to intense near work at school and learning to read in preschool at an early age. PURPOSE This study aimed to assess factors that may influence myopia in three groups of Jewish boys with different educational demands. METHODS Healthy ultra-Orthodox, religious, and secular Jewish boys (n = 36) aged 8 to 12 years participated. Refractive status, education, time spent reading and writing, and electronic device use were assessed using a questionnaire, and time outdoors and physical activity were assessed objectively using an Actiwatch. Data were analyzed with χ2 and Kruskal-Wallis tests with Bonferroni post hoc comparisons. RESULTS Ultra-Orthodox (n = 14) and religious (n = 13) children had greater myopia prevalence compared with secular children (n = 9; P = .01), despite no differences in parental myopia. Actigraph data showed that there were no differences in activity (P = .52) or time spent outdoors (P = .48) between groups. Ultra-Orthodox children learned to read at a younger age and spent more hours at school (P < .001 for both). All groups engaged in a similar amount of near work while not in school (P = .52). However, ultra-Orthodox boys had less electronic device use than did religious (P = .007) and secular children (P < .001). CONCLUSIONS This pilot study demonstrates that ultra-Orthodox, religious, and secular children have distinct educational demands but similar time outdoors, physical activity, and near work while not in school. The findings suggest that near work at school and/or learning to read in preschool at an early age may contribute to previously reported differences in refractive error between groups. However, conclusions should be confirmed in a larger sample size.

Purpose To explore whether subtle changes in visual quality can be detected using different measures of visual function against the quick contrast sensitivity function test (quick CSF). Methods Sixty participants, aged 17 to 34 years, were enrolled. Participants' vision was degraded by 0.25 D undercorrection (0.25 D), 60% neutral density filter brightness reduction (60% ND), and 0.8 Bangerter foil optical diffusion (0.8BAN). Visual function tests including visual acuity and contrast sensitivity (CSV-1000E and quick CSF) were measured with participant's best-corrected vision and under simulated visual degradation conditions. Test sensitivities in detecting differences were compared. Results Statistically significant visual acuity degradation was observed in the 0.8BAN condition only (Pcorrected < 0.001). With CSV-1000E and outliers removed, significant CS degradation was observed in all spatial frequencies, area under log CSF (AULCSF) in the 0.8BAN condition (Pcorrected < 0.001 for all), medium and high spatial frequencies and AULCSF in the 60%ND condition (Pcorrected,6cpd = 0.002, Pcorrected,12cpd = 0.005, Pcorrected,18cpd = 0.001, Pcorrected,AULCSF < 0.001) and the 0.25 D condition (Pcorrected,6cpd = 0.011, Pcorrected,12cpd = 0.013, Pcorrected,18cpd = 0.015, Pcorrected,AULCSF < 0.001). With the quick CSF, significant CS degradation was observed in all simulated visual conditions in all spatial frequencies, cutoff frequency and AULCSF (Pcorrected < 0.001 for all). Test-retest reliability of the quick CSF method was high; coefficient of repeatability ranged from 0.14 to 0.18 logCS. Conclusions Compared with visual acuity and chart-based CS tests, the quick CSF method provided more reliable and sensitive measures to detect small visual changes. Translational Relevance The quick CSF method can provide sensitive and reliable measures to monitor disease progression and assess treatment outcomes.

This report evaluates the role of the combined visual abilities of acuity, contrast sensitivity and presentation time on plate discipline and baseball batting performance. A visual function test (EVTS) was performed on 585 professional baseball players. The results were compared to several common plate-discipline measures. The EVTS test provides a single measure combining target size, contrast and presentation time. Correlations (statistically significant) were found between this measure and several plate discipline metrics (InzoneSwingPct, inzoneFbSwingPct, ChasePct, FbChasePct, BBperPa). Years of major league service did not appear to be related to visual ability. When comparing the best and worst 20% groups based on visual ability, statistically significant improvements ranging from 11.6% in BBperPa to 3.5% in inzoneSwingPct were noted in the better visual function group. Effect sizes ranged from 0.278 to 0.387. These results demonstrate the relationship between basic visual function and batting performance. These are the first results, on a large group at the professional level, to demonstrate this relationship statistically. These results may aid player selection, indicating that batters with better visual function are more likely to be successful when batting and more productive for their team.

To describe the course of intermittent exotropia (IXT) in children followed up without treatment for 3 years.Observation arm from randomized trial of short-term occlusion versus observation.One hundred eighty-three children 3 to 10 years of age with previously untreated IXT and 400 seconds of arc (arcsec) or better near stereoacuity.Participants were to receive no treatment unless deterioration criteria were met at a follow-up visit occurring at 3 months, 6 months, or 6-month intervals thereafter for 3 years.The primary outcome was deterioration by 3 years, defined as meeting motor criterion (constant exotropia ≥10 prism diopters [Δ] at distance and near) or near stereoacuity criterion (≥2-octave decrease from best previous measure). For the primary analysis, participants also were considered to have deteriorated if treatment was prescribed without meeting either deterioration criterion.The cumulative probability of protocol-specified deterioration by 3 years was 15% (95% confidence interval, 10%-22%), but that was likely an overestimate, partly because of misclassification. Among 25 deteriorations, 2 met motor deterioration, 11 met stereoacuity deterioration, and 12 started treatment without meeting either criteria (7 for social concern, 1 for diplopia, 4 for other reasons). Among the 132 participants who completed the 3-year visit and had not been treated during the study, only 1 (1%) met motor or stereoacuity deterioration criteria at 3 years. Of the 4 participants completing the 3-year visit who met deterioration criteria previously and had not started treatment, none still met deterioration criteria. Between the baseline and 3-year examination for these 132 patients, improvement occurred in distance and near stereoacuity (mean improvement, 0.14 and 0.14 logarithm of arcsec; P ≤ 0.001 and P ≤ 0.001, respectively), distance exotropia control (mean improvement, 0.6 points; P ≤ 0.001), and distance exodeviation magnitude (mean improvement, 2.2 Δ; P = 0.002).Among children 3 to 10 years of age with IXT for whom surgery was not considered to be the immediately necessary treatment, stereoacuity deterioration or progression to constant exotropia over 3 years was uncommon, and exotropia control, stereoacuity, and magnitude of deviation remained stable or improved slightly.

PURPOSE: Clinical evaluation of the visual outcomes after implantation of a small-aperture extended depth of focus (EDOF) intraocular lens (IOL) and a segmental refractive bifocal lens. METHODS: In this prospective study, 13 patients with cataract received a small-aperture IC-8 IOL (AcuFocus, Irvine, CA) in one eye and a segmental-refractive Lentis Mplus LS-313 MF20 IOL (Oculentis, Berlin, Germany) in the fellow eye. The clinical examination included measurements of uncorrected (UDVA) and corrected (CDVA) distance visual acuity, uncorrected (UIVA) and distance-corrected (DCIVA) intermediate visual acuity, and uncorrected (UNVA) and distance-corrected (DCNVA) near visual acuity. Additionally, a defocus curve was obtained from +2.00 to −5.00 diopters (D) and a Salzburg Reading Desk was used to assess the patients' reading acuity at intermediate and near distances. A halo and glare simulator was used to evaluate the postoperative perception of dysphotopsia. RESULTS: At 5 months postoperatively, the mean binocular visual results demonstrated UDVA, UIVA, and UNVA values of −0.04 ± 0.11, 0.00 ± 0.10, and 0.11 ± 0.08 logMAR, respectively. The binocular distance-corrected reading performance test also confirmed the improved visual function, with an intermediate reading acuity of 0.12 logMAR at 69.21 cm and a near reading acuity of 0.19 logMAR at 41.63 cm. The mean halo size was 32.54 ± 22.38, mean halo intensity was 34.46 ± 21.95, mean glare size was 9.00 ± 17.47, and mean glare intensity was 9.92 ± 16.84. CONCLUSIONS: The new concept of a combined implantation of a small-aperture IOL and a segmental-refractive bifocal lens showed good results in far and intermediate distances and functional results at near distance, while causing minimal photic phenomena. [ J Refract Surg. 2019;35(9):551–558.]

SIGNIFICANCE The present study addresses the accommodative response and its dependence on the type of optical correction used. The results are discussed relative to their possible implications for myopia progression and visual fatigue. PURPOSE The accommodative response has been investigated owing to its possible relationship with the onset and progression of myopia and visual fatigue. This study explored the influence of wearing soft contact lenses in comparison with spectacles in terms of magnitude and variability of accommodation. In addition, we analyzed the intersession and intermethod repeatability. METHODS Dynamic accommodative response was recorded during 30-second epochs, at five different distances (50, 40, 33, 25, and 20 cm), in 21 individuals (mean refractive error ± SD, -0.79 ± 1.39 D) while wearing either soft contact lenses or spectacles on two different days. To assess repeatability, a second identical intervention was conducted. RESULTS Higher lags of accommodation were obtained with the use of soft contact lenses in comparison with the spectacle condition (P =.04, partial η 2 [η p 2] = 0.204), and similarly, a higher variability of accommodation at near distances was found during the soft contact lens measurement (P

SIGNIFICANCE: Uncorrected refractive error is the leading cause of visual impairment; therefore, reducing its prevalence is important worldwide. For two decades, there has not been a comprehensive assessment of refractive error in Latin America. PURPOSE: The purpose of this study was to determine the current prevalence of refractive error, presbyopia, spectacle coverage, barriers to uptake refractive services, and spectacle correction in people 15 years and older in Bogotá, Colombia. METHODS: A cross-sectional community-based survey was conducted using 50 randomly selected clusters from 10 districts of Bogotá reflecting the socioeconomic status of the city. Respondents 15 years and older were interviewed and underwent standardized clinical eye examinations. Prevalence of uncorrected refractive error, spectacle coverage, and visual impairment were standardized to 2015 age-sex population distribution of Bogotá and further analyzed. RESULTS: A total of 2886 subjects (90% of 3206 eligible subjects) participated in the study; 39.1% were male and 60.9% were female in the age range of 15 to 96 years, with a median age of 46 years (interquartile range, 45 to 54 years). Age- and sex-standardized prevalence of visual impairment was 19.3% (95% confidence interval [CI], 17.8 to 20.8%). Prevalence of uncorrected refractive error was 12.5% (95% CI, 11.3 to 13.7%). Prevalence of presbyopia among participants 35 years and older was 55.2% (95% CI, 52.9 to 57.4%). Spectacle coverage was 50.9% for distance vision, and it was 33.9% for presbyopia. Main barrier to spectacle uptake was a limitation in affording spectacles because of economic factors (29.5%). CONCLUSIONS: This study provides a current estimate of refractive error using the Rapid Assessment of Refractive Error for Colombia and the Latin American region. The prevalence of uncorrected refractive error and presbyopia was high, and the barriers to spectacle uptake were higher in the lowest socioeconomic strata. The results obtained in the present study will help in making evidence-based decisions related to eye care service delivery in Colombia.

SIGNIFICANCE Glaucoma has been shown to impair hazard detection ability and increase crash risk compared to controls. Differences in visual search behavior of the driving scene may explain these differences; however, there has been limited investigation of this issue with inconsistent findings. PURPOSE Through eye movement tracking of older drivers with glaucoma, we explored their visual search behavior in comparison with controls while performing the DriveSafe, a slide recognition test purported to predict fitness to drive. METHODS Thirty-one drivers with glaucoma (mean age, 71.7 ± 6.3 years; average better-eye mean defect,-3 dB; average worse-eye mean defect,-12 dB) and 25 age-matched controls underwent measurements of their visual acuity, contrast sensitivity, visual fields, and useful field of view (visual processing speeds). Participants' eye movements were recorded while they completed the DriveSafe test, which consists of brief presentations of static, real-world driving scenes containing various road users (pedestrians, bicycles, vehicles). Participants reported the types, positions, and direction of travel of road users in each image; the score was the total number of correctly reported items (maximum, 128). RESULTS Drivers with glaucoma had significantly worse DriveSafe scores (P = .03), fixated on road users for shorter durations (P < .001), and exhibited smaller saccades (P = .02) compared with controls. For all participants, longer fixation times on road users (P < .001) was the eye movement measure most strongly associated with better DriveSafe scores; this relationship was not significantly different between groups. Useful field-of-view divided attention was the strongest visual predictor of DriveSafe scores. CONCLUSIONS Eye movement changes in the glaucoma group may reflect increased difficulty in identifying relevant objects in the visual scene, which may be related to their lower DriveSafe scores. Given the DriveSafe's potential utility in assessing drivers with visual impairment before on-road testing, further investigations on how DriveSafe performance and eye movement patterns compare to those during on-road driving are warranted.

PURPOSE: To compare the accuracy of intraocular lens (IOL) power calculation based on standard keratometry (K) and the new Total Keratometry (TK). METHODS: A post-hoc analysis of study data based on 145 pseudophakic astigmatic eyes was conducted. The absolute prediction error (APE) of spherical equivalent (SE) and cylinder (CYL) was calculated based on K and TK (including posterior corneal surface) data recorded 6 weeks after IOL implantation. APE was calculated as the difference between the postoperative refraction and the refractive error predicted by three classic IOL calculation methods (Haigis/Haigis-T, Barrett Universal II, Barrett Toric Calculator) and two new formulas developed for TK (Barrett TK Universal II, Barrett TK Toric). For APE in SE, the Haigis-T (K versus TK) and Barrett Universal II (K) versus Barrett TK Universal II (TK) were compared. For APE in CYL, the Haigis-T (K versus TK) and Barrett Toric Calculator (K) versus Barrett TK Toric formula (TK) were compared. RESULTS: Mean APE in SE and CYL was lower based on TK values compared to K, with a mean APE difference (K − TK) of 0.011 ± 0.107 diopters (D) (SE Haigis-T; 95% confidence interval [CI]: −0.004 to infinity), 0.016 ± 0.113 D (SE: Barrett Universal II versus Barrett TK Universal II; 95% CI: 0.0005 to infinity), 0.103 ± 0.173 D (CYL: Haigis-T; 95% CI: 0.0791 to infinity), and 0.020 ± 0.148 D (CYL: Barrett Toric versus Barrett TK Toric; 95% CI: −0.0002 to infinity). APE in SE was within ±0.50 D in 86% (Barrett TK Universal II) versus 84% (Barrett Universal II) of eyes. APE in CYL was within ±0.50 D in 58% (Haigis from TK) versus 44% (Haigis from K) of eyes. CONCLUSIONS: In comparison to standard K, a higher prediction accuracy can be expected by using TK values along with the two newly developed formulas. TK values are compatible with standard IOL power calculation formulas and existing optimized IOL constants. [ J Refract Surg. 2019;35(6):362–368.]

Significance Self-adjustable spectacles are increasingly being used in refractive service delivery programs in developing countries. Despite the success of self-refraction as a refraction technique, compliance with actual wear of adjustable spectacles has not been evaluated. Findings in this study have significant programmatic implications for the effectiveness and sustainability of this mode of correction in developing countries. Purpose The purpose of this study was to assess compliance with wearing of adjustable spectacles and factors associated with compliance in pre-teen schoolchildren at 6 months after spectacles were dispensed. Methods A cohort of 86 children aged 6 to 12 years with presenting vision worse than or equal to 6/12 in the better eye that could be improved to better than or equal to 6/7.5 by subjective refraction and who were identified from a randomized sample of 18 primary schools in the coastal areas of Cape Coast in Ghana received free FocusSpecs adjustable spectacles after successfully completing self-refraction and cycloplegic subjective refraction. Follow-up examination to assess compliance and to determine reasons for noncompliance was conducted at 6 months after spectacle provision. Logistic regression models assessed factors associated with spectacle wear compliance (95% confidence intervals [CIs]). Results Spectacle wear compliance was 33.7% (95% CI, 31.3 to 36.1%); an additional 29% had their spectacles with them but were not wearing them. The major reasons given by the children for noncompliance were "loss" (32%; 18/57) and "breakage" (23%; 13/57). Modest compliance (49%) was observed among the poorer children who attend public schools. Attending public school was the only predictor of compliance to spectacle wear (odds ratio, 3.096; 95% CI, 1.228 to 7.805; P = .02). Conclusions Despite accurate self-refraction by most children, only a small proportion was compliant with actual wear of the spectacles. Loss and breakage were the major reasons for noncompliance. The poorer children who attend public schools, who stand to benefit most from the technology, were the ones more likely to be compliant with wear.

Significance Well-established charts such as Early Treatment Diabetic Retinopathy Study are able to quantify visual acuity (VA) with a low cutoff of 1.6 logMAR. Below this point, nonquantitative measures, such as count fingers, hand movements, and light perception, are used. There is a need for more reproducible, comparable, and reliable ways to measure VA changes in this patient cohort. Purpose The purpose of this study was to examine and compare the ability of the Berkeley Rudimentary Vision Test (BRVT) and the Freiburg Acuity Test (FrACT) to quantify VA in low-vision patients who score nonnumerical VAs in standard charts. Methods Fifty adult participants with VA ≤1.0 logMAR in both eyes were recruited from the Oxford Eye Hospital, Oxford, United Kingdom. Correlation between FrACT and BRVT results and the correlation between VA and daily living activities were analyzed statistically. Potential predictors of differences were investigated. Results The BRVT was significantly faster to conduct (P = .002), but FrACT was able to quantify vision numerically in a greater proportion of eyes. The κ agreement between tests was 0.26. The difference increased systematically with the VA reduction (P < .0001). The Bland-Altman analysis showed a skew to measurement of lower logMAR VA indicating better vision measured on the FrACT. The only significant predictor of difference between the tests was binocular VA (coefficient, −0.445; P = .001). Conclusions Both tests are suitable for a very low-vision population. The BRVT is a faster test to administer, but FrACT provides a numerical result in more eyes. The poor intertest repeatability indicates that they cannot be used interchangeably. The BRVT generally reported poorer vision than did the FrACT. The medium of presentation, such as a computer screen or externally lit print medium, is likely to be the biggest factor in these differences and warrants further investigation.

The MNREAD chart consists of standardized sentences printed at 19 sizes in 0.1 logMAR steps. There are 95 sentences distributed across the five English versions of the chart. However, there is a demand for a much larger number of sentences: for clinical research requiring repeated measures, and for new vision tests that use multiple trials at each print size. This paper describes a new sentence generator that has produced over nine million sentences that fit the MNREAD constraints, and demonstrates that reading performance with these new sentences is comparable to that obtained with the original MNREAD sentences. We measured reading performance with the original MNREAD sentences, two sets of our new sentences, and sentences with shuffled word order. Reading-speed versus print-size curves were obtained for each sentence set from 14 readers with normal vision at two levels of blur (intended to simulate acuity loss in low vision) and with unblurred text. We found no significant differences between the new and original sentences in reading acuity and critical print size across all levels of blur. Maximum reading speed was 7% slower with the new sentences than with the original sentences. Shuffled sentences yielded slower maximum reading speeds and larger reading acuities than the other sentences. Overall, measures of reading performance with the new sentences are similar to those obtained with the original MNREAD sentences. Our sentence generator substantially expands the reading materials for clinical research on reading vision using the MNREAD test, and opens up new possibilities for measuring how text parameters affect reading.

PURPOSE: To assess early visual and optical quality recovery according to preoperative refraction after small incision lenticule extraction (SMILE) at low energy level for myopia and myopic astigmatism treatment. METHODS: This prospective study included 101 eyes of 101 patients separated into three groups: low myopia (30 eyes), with a mean spherical equivalent (SE) of −2.13 ± 0.73 diopters (D); moderate myopia (33 eyes), with a mean SE of −4.53 ± 0.86 D; and high myopia (38 eyes), with a mean SE of −6.54 ± 0.78 D. Visual acuity, contrast sensitivity, refraction, corneal higher order aberrations, modulation transfer function, Strehl ratio, and Objective Scatter Index (OSI) were measured. RESULTS: All eyes had a corrected distance visual acuity of 20/20 or better at 1 day in the low myopia group and 1 month in the moderate and high myopia groups. The contrast sensitivity preoperative values recovered at 8 days in the low myopia group and 1 month in the moderate and high myopia groups. At 1 month, the low myopia group recovered the OSI preoperative values (0.61 to 0.69) and the OSI values were slightly higher than the preoperative value in the moderate and high myopia groups (0.74 to 1.00 and 0.8 to 1.14, respectively). CONCLUSIONS: The recovery time of visual and optical quality in the first month after SMILE correlated with preoperative refraction and the amount of postoperative scattering. Patients with low myopia recovered visual acuity faster and with less ocular scattering than patients with moderate or high myopia. [ J Refract Surg . 2019;35(5):285–293.]

ObjectiveTo study if the thalamic lateral geniculate nucleus (LGN) is affected in multiple sclerosis (MS) due to anterograde degeneration from optic neuritis (ON) or retrograde degeneration from optic radiation (OR) pathology, and if this is relevant for visual function.MethodsIn this cross-sectional study, LGN volume of 34 patients with relapsing-remitting MS and 33 matched healthy controls (HC) was assessed on MRI using atlas-based automated segmentation (MAGeT). ON history, thickness of the ganglion cell–inner plexiform layer (GC-IPL), OR lesion volume, and fractional anisotropy (FA) of normal-appearing OR (NAOR-FA) were assessed as measures of afferent visual pathway damage. Visual function was tested, including low-contrast letter acuity (LCLA) and Hardy-Rand-Rittler (HRR) plates for color vision.ResultsLGN volume was reduced in patients vs HC (165.5 ± 45.5 vs 191.4 ± 47.7 mm3, B = −25.89, SE = 5.83, p < 0.001). It was associated with GC-IPL thickness (B = 0.95, SE = 0.33, p = 0.006) and correlated with OR lesion volume (Spearman ρ = −0.53, p = 0.001), and these relationships remained after adjustment for normalized brain volume. There was no association between NAOR-FA and LGN volume (B = −133.28, SE = 88.47, p = 0.137). LGN volume was not associated with LCLA (B = 5.5 × 10−5, SE = 0.03, p = 0.998), but it correlated with HRR color vision (ρ = 0.39, p = 0.032).ConclusionsLGN volume loss in MS indicates structural damage with potential functional relevance. Our results suggest both anterograde degeneration from the retina and retrograde degeneration from the OR lesions as underlying causes. LGN volume is a promising marker reflecting damage of the visual pathway in MS, with the advantage of individual measurement per patient on conventional MRI.

Vision impairments are prevalent, but underdiagnosed in individuals with dementia living in long-term care (LTC). Effective screening tools could identify remediable vision problems. This scoping review was conducted to identify vision screening tests used with individuals with dementia and assesses their suitability for administration by nurses in LTC. A literature search using the Arksey and O’Malley (2005) method included research articles, conference proceedings, and dissertations. Data were included from participants over 65 years of age with a diagnosis of probable dementia. A panel of vision experts evaluated the suitability of the candidate vision tests. The search yielded 179 publications that met the inclusion criteria. Of 134 vision tests that were identified, 19 were deemed suitable for screening by nurses in LTC. Tests screened for acuity (12), visual field (1), anatomy (2), color vision (2), and general visual abilities (2). Tests were excluded because of complexity of interpretation (90), need for specialized training (83), use in research only (57), need for specialized equipment (54), not assessing visual function (44), long test duration (21), uncommonness (13), and needing an act reserved for specialists (7). Psychometric properties were not often reported for tests. Few of the tests identified had been validated for use with individuals with dementia. Based on our review, few tests were deemed suitable for use by nurses to assess this population in LTC. Identifying appropriate tools to screen vision in individuals with dementia is a necessary first step to interventions that could potentially improve functioning and quality of life.

Tests of contrast sensitivity (CS) are not routinely performed in the clinic, although CS is reduced in many conditions, such as amblyopia or glaucoma. This may be due to perceived time constraints or unaffordability of equipment.Monocular CS functions obtained with the FACT, CSV 1000E, and Lea Symbols were compared in 19 healthy subjects aged 24 - 78 years and 24 subjects aged 5 - 16 years, 9 of whom had amblyopia.CS functions could be obtained with all three tests. The tests were equally comfortable for young and adult patients, and took less than 5 minutes to perform (one eye). All measured CSs at 3, 6, 12, and 18 cycles per degree (cpd), but the FACT included 1.5 cpd. LINEAR MIXED EFFECT MODELS: were performed. While there was no significant difference at low spatial frequencies, the Lea CS test showed a ceiling effect in that range, while the FACT showed a floor effect at high spatial frequencies. CS in amblyopic children did not differ between the contralateral and the amblyopic eye. Overall, amblyopic eyes had lower CS values than the control eyes and CS did not correlate significantly to visual acuity at distance.All three CS tests could be usefully applied in the clinic in adults as well as children over the age of 4 years. Only the CSV 1000E exhibited neither a ceiling nor a floor effect. This was also the fastest test. In children with amblyopia, CS testing offers additional information on visual function. In contrast to previous reports, we did not find that the CSV and FACT are interchangeable.Obwohl Kontrastempfindlichkeit bei vielen Augenkrankheiten wie Amblyopie oder Glaukom vermindert ist, werden Kontrastempfindlichkeitstest nicht routinemäßig durchgeführt. Der Grund dafür liegt womöglich in der Zeitknappheit oder an mangelnder Ausrüstung.Kontrastempfindlichkeitsfunktionen wurden mit 3 verschiedenen Tests: FACT, CSV-1000E und Lea Symbolen monokular bei 19 gesunden Erwachsenen (24 – 78 J) und 15 gesunden und 9 amblyopen Kindern (5 – 16 J) gemessen und miteinander verglichen.Mit allen 3 Tests konnten Kontrastempfindlichkeitsfunktionen erhalten werden. Die Tests waren vergleichbar angenehm für Jung und Alt und dauerten alle weniger als 5 Minuten (1 Auge). Während alle Tests Kontrastempfindlichkeiten bei 3, 6, 12 und 8 Zyklen pro Grad messen, werden mit dem FACT auch Werte bei 1,5 Zyklen pro Grad gemessen. Lineare Mixed-Effect-Modelle wurden erstellt. In tiefen Ortsfrequenzen ergab sich keine signifikante Differenz. Lea zeigte einen Ceiling-Effekt in den tiefen und FACT ein Floor-Effekt in den hohen Ortsfrequenzen. Bei den amblyopen Kindern bestand kein signifikanter Unterschied zwischen dem amblyopen und dem Partnerauge. Insgesamt hatten die amblyopen Augen tiefere Kontrastempfindlichkeiten als die Kontrollen und korrelierten nicht signifikant mit dem Fernvisus.Alle Tests können sowohl bei Erwachsenen als auch bei Kindern über 4 Jahren sinnvoll in der Praxis eingesetzt werden. Für Kinder mit Amblyopie liefert die Kontrastempfindlichkeit zusätzliche Informationen über die visuelle Funktion. Im Gegensatz zur Literatur waren FACT und CSV nicht austauschbar. Der CSV ließ sich am schnellsten durchführen und zeigte als einziger Test weder einen Floor- noch einen Ceiling-Effekt.

Two case studies in the literature report on patients with infantile nystagmus (IN) who preferred to read text that is oriented vertically rather than horizontally. The current study systematically evaluated the effect of text orientation (−60 to +90 deg with respect to horizontal) on reading speed in nine individuals with IN associated with albinism at Hadassah Academic College (HAC), seven individuals with IN at the University of Houston (UH), and a total of 17 normal control observers. Observers at HAC read 40-character passages of Hebrew text from standardized 2nd grade level reading material and observers at UH read MNRead acuity chart sentences. Letter size was two to six lines larger than each observer’s measured visual acuity. In both individuals with IN and normal observers reading speed was fastest for horizontally oriented text and decreased for other orientations. However, reading speed decreased significantly more for non-horizontally orientated text in the observers with IN, compared to controls. In general, it is recommended that to achieve best reading performance patients with IN read horizontally oriented text.

PURPOSE: To evaluate the outcomes of primary topography-guided laser in situ keratomileusis (LASIK) in eyes with subjective refractive astigmatism of 2.00 diopters (D) or greater. METHODS: This was a prospective study in consecutive eyes with cylinder of 2.00 D or greater that had LASIK using the Alcon WaveLight EX500 excimer laser and T-CAT/Contoura software (Alcon Laboratories, Inc., Fort Worth, TX). The accuracy, efficacy, safety, cylinder vector analysis, higher order aberrations, and patients' subjective quality of vision were assessed. Eyes with naturally occurring topographic irregular astigmatism were not excluded. RESULTS: The mean cylinder was −2.55 D preoperatively and −0.34 D postoperatively; 81% and 95% of eyes were within ±0.50 and ±0.75 D of intended cylinder after LASIK, respectively. The correction index and index of success were 1.00 and 0.13, respectively. The efficacy and safety indexes were 0.98 and 1.04, respectively. The preoperative corneal topography irregularity index, anterior corneal higher order aberrations, and refractive astigmatism magnitude were mildly correlated to postoperative residual astigmatism. Mean ocular and corneal coma were not increased postoperatively. Patients had significant improvements after LASIK in both subjective uncorrected quality of vision and night vision disturbances compared to spectacle- and contact lens–corrected vision before LASIK. CONCLUSIONS: Topography-guided ablation using the Alcon WaveLight EX500 excimer laser and T-CAT/Contoura software results in excellent accuracy, efficacy, and safety, with improved postoperative subjective quality of vision and reduced night vision disturbances in virgin eyes with refractive astigmatism of 2.00 D or greater, including eyes with topographic naturally occurring irregular astigmatism. [ J Refract Surg. 2019;35(2):78–86.]

Pediatric vision screening has been shown to reduce the prevalence of amblyopia. To assess the current local situation in the Canton of St. Gallen, a survey study was performed.A standardized questionnaire was sent to 191 general practitioners and school doctors to obtain information on the currently applied vision screening protocols for children. The questionnaire included 17 questions with multiple answers possible.Sixty-seven participants (35%) answered the survey. Overall, 61 (91%) of the repliers confirmed that some sort of vision screening exists. According to 45 (67%) repliers, a mandatory examination exists. As to the question about the person performing the examination, multiple answers were given; 39 (44%) answered that the secretary or the medical practical assistant performs the vision tests, 15 (17%) indicated the school doctor, and 25 (28%) indicated the general practitioner or the pediatrician. Most screening tests are performed in a general practitioner's practice (32; 40%), some are done in the kindergartens (17; 21%), and others are done in a pediatrician's practice (17; 21%). The majority of children are tested at the age of 5 - 6 years (58, 87%). Sixty-one (91%) of the repliers indicated that at least the children's visual acuity is measured. Acuity is assessed with different methods, mainly, with pictures (20; 30%), numbers (23; 34%), and Snellen optotypes (33; 49%).There are no consistent regulations regarding vision screening in the Canton of St. Gallen. Actually, rather different screening scenarios exist. Tests are performed by a variety of people in different locations with diverse testing procedures. A standardization of the applied screening procedures at cantonal and national levels seems reasonable.Sehscreening bei Kindern führt zu einer Reduktion der Amblyopieprävalenz. In der vorliegenden Studie wurden die lokalen Gegebenheiten mit einer Meinungsumfrage untersucht.Ein standardisierter Fragebogen mit 17 Fragen und möglichen Mehrfachantworten wurde an 191 Allgemeinmediziner und Schulärzte versandt, um die geübte Praxis des Sehscreenings bei Kindern zu erheben.Die Rücklaufquote betrug 35% (67 Teilnehmer). 61 befragte Personen (91%) bestätigten, dass ein Sehscreening durchgeführt wird. 45 der Befragten (67%) bestätigten verbindliche Richtlinien. Die Untersuchung wird von einem breiten Personenkreis durchgeführt: In 39 Fällen (44%) werden diese durch die Sekretärin oder durch medizinisches Assistenzpersonal ausgeführt, in 15 Fällen (17%) obliegt sie dem Schularzt und in 25 Fällen (28%) dem Hausarzt oder dem Pädiater. Die Untersuchung erfolgt zumeist in der Praxis des Hausarztes (32, 40%), aber auch im Kindergarten (17, 21%) und beim Kinderarzt (17, 21%). Die meisten Kinder werden im Alter von 5 – 6 Jahren getestet (58, 86%). Gemäß Umfrage wird in erster Linie der Visus erhoben (61, 91%). Die Visusprüfung erfolgt unterschiedlich; vor allem mit Snellen-Optotypen (33, 49%), Zahlen (23, 34%) und Kinderbildern (20, 30%).Einheitliche Richtlinien für das Sehscreening bei Kindern existieren im Kanton St. Gallen nicht. Das führt zu recht unterschiedlichen Szenarien bezüglich involvierter Personen, Untersuchungsorten und angewendeter Testverfahren. Die Untersuchung der Kinder erfolgt eher spät. Eine Vereinheitlichung der Screeningabläufe auf kantonaler und nationaler Ebene scheint sinnvoll.

To identify risk factors for axial length (AL) elongation and incident school myopia.Population-based prospective birth-cohort study.Four thousand seven hundred thirty-four children examined at 6 and 9 years of age from the Generation R Study in Rotterdam, The Netherlands.Axial length and corneal radius (CR) were measured with an IOLMaster 500 and daily life activities and demographic characteristics were obtained by questionnaire. Three thousand three hundred sixty-two children (71%) were eligible for cycloplegic refractive error measurements. Linear regression models on AL elongation were used to create a risk score based on the regression coefficients resulting from environmental and ocular factors. The predictive value of the prediction score for myopia (≤-0.5 diopter) was estimated using receiver operating characteristic curves. To test if regression coefficients differed for baseline AL-to-CR ratio, interaction terms were calculated with baseline AL-to-CR ratio and environmental factors.Axial length elongation and incident myopia.From 6 to 9 years of age, average AL elongation was 0.21±0.009 mm/year and myopia developed in 223 of 2136 children (10.4%), leading to a myopia prevalence at 9 years of age of 12.0%. Seven parameters were associated independently (P0.05) with faster AL elongation: parental myopia, 1 or more books read per week, time spent reading, no participation in sports, non-European ethnicity, less time spent outdoors, and baseline AL-to-CR ratio. The discriminative accuracy for incident myopia based on these risk factors was 0.78. Axial length-to-CR ratio at baseline showed statistically significant interaction with number of books read per week (P0.01) and parental myopia (P0.01). Almost all predictors showed the highest association with AL elongation in the highest quartile of AL-to-CR ratio; incidental myopia in this group was 24% (124/513).Determination of a risk score can help to identify school children at high risk of myopia. Our results suggest that behavioral changes can offer protection particularly in these children.

Purpose To examine the feasibility of saccadic vector optokinetic perimetry (SVOP), an automated eye tracking perimeter, as a tool for visual field (VF) assessment in infants. Methods Thirteen healthy infants aged between 3.5 and 12.0 months were tested binocularly using an adapted SVOP protocol. SVOP uses eye tracking technology to measure gaze responses to stimuli presented on a computer screen. Modifications of SVOP for testing infants included adjusting the fixation target to display a short animation, increasing the stimulus size to equivalent to Goldmann V, and introducing a tiered test pattern strategy. Binocular, single-quadrant confrontation VF testing and Keeler preferential looking cards visual acuity testing was also performed. Results Using multiple test attempts when required, all but the youngest infant (12 of 13 [92.3%]) successfully completed a 4-point screening test. Seven infants (53.8%) successfully completed the 12-point test, four (30.8%) successfully completed the 20-point test, and three (23.1%) successfully completed the 40-point test. The effect of multiple test attempts and the complexity of the test pattern (number of test points) on performance was investigated, including test completion rate, percentage of correctly seen stimuli, and average time per tested stimulus. Conclusions The modified SVOP test strategy allowed successful assessment of binocular VFs in healthy infants. Future data collection from larger cohorts of infants is needed to derive normative limits of detection and assess accuracy in detecting and monitoring infant VF abnormalities. Translational relevance Eye tracking perimetry may provide a useful method of automated VF assessment in infants.

The SpeedWheel (SW) test is an objective test of visual acuity (VA) using suppression of the optokinetic nystagmus (OKN). Here, we established prediction intervals of the SW measures compared to Snellen acuity in adults and children.In this prospective, single center study, subjects aged at least 4 years underwent testing of VA with SW, Landolt-C, and Tumbling-E symbols (Freiburg acuity test: FrACT-C, FrACT-E). Prediction intervals were established for SW compared to FrACT-C or -E and for FrACT-E compared to FrACT-C. Mixed linear effect models were applied for statistical analysis.From 241 subjects, 471 eyes were included: median age 36 years, range 4 - 88 years, 43.6% male, 56.4% female. Eyes included were either healthy or had various underlying ophthalmic conditions. Prediction intervals for SW to estimate FrACT-C or -E acuity showed a similar range compared to the prediction interval of FrACT-C for the estimation of FrACT-E acuity. For each acuity step, there was no influence of age. Up to an SW acuity of 0.7 logMAR, 80% of the subjects had a FrACT-C acuity that was at most 1.6 logMAR lines below, and for an SW acuity of 1.0 logMAR, FrACT-C acuity was not worse than 4 logMAR lines. Prediction intervals for eyes with refractive error, cataract, visual field loss and retinal disease did not differ significantly from healthy eyes in contrast to eyes with amblyopia or multiple ophthalmic disorders. SW correlated well to FrACT tests and results of a previous study fell within our prediction estimates.Our prediction intervals for SW acuity may be used to estimate Snellen acuity (FrACT-C and -E) in the clinic in adults and children unable to cooperate in other acuity testing.Der SpeedWheel-Test (SW-Test) ästimiert die Sehschärfe mittels Suppression des optokinetischen Nystagmus (OKN). Wir erhoben Vorhersageintervalle für SW verglichen mit dem Snellen-Visus für Erwachsene und Kinder.In dieser prospektiven Studie wurde die Sehschärfe bei Probanden ab 4 Jahren mittels SW, FrACT-C, FrACT-E (Freiburg Acuity Test) erhoben. Vorhersageintervalle für den SW-Visus wurden im Vergleich zu FrACT-C und FrACT-E und für FrACT-E im Vergleich zu FrACT-C erstellt. In der statistischen Analyse kamen lineare gemischte Modelle zur Anwendung.471 Augen von 241 Probanden wurden eingeschlossen: Altersmedian 36 Jahre (4 – 88 Jahre), 43,6% männlich, 56,4% weiblich. Die Probandengruppe beinhaltete neben gesunden Augen auch solche mit vorbestehenden ophthalmologischen Erkrankungen. Die Vorhersageintervalle des SW im Vergleich zu den FrACT-Tests war vergleichbar mit dem Vorhersageintervall des FrACT-E-Tests bezogen auf den FrACT-C-Test. Für die verschiedenen Visusstufen ließ sich kein signifikanter Einfluss des Alters nachweisen. Für einen SW-Visus bis 0,7 logMAR war der FrACT-C-Visus bei 80% nicht schlechter als 1,6 logMAR-Zeilen und bei einem SW-Visus von 1,0 logMAR nicht schlechter als 4 logMAR-Zeilen. Augen mit refraktiven Fehlern, Katarakt, Gesichtsfeldeinschränkungen oder retinalen Krankheiten zeigten, im Unterschied zu Amblyopen oder Augen mit mehreren Augenkrankheiten, keinen signifikanten Unterschied zu Gesunden. SW korrelierte gut mit den FrACT-Tests. Daten einer Vorgängerstudie lagen innerhalb unserer Vorhersageintervalle.Unsere Vorhersageintervalle für SW können bei Erwachsenen und bei Kindern mit unzureichender Kooperation für einen subjektiven Sehtest helfen, um die Snellen-Sehschärfe (FrACT-C bzw. FrACT-E) zu ästimieren.

Patients with mild traumatic brain injuries (mTBI) often report difficulties in motor coordination and visuo-spatial attention. However, the consequences of mTBI on fine motor and visuo-motor coordination are still not well understood. We aimed to evaluate whether mTBI had a concomitant effect on fine motor ability and visuo-motor integration and whether this is related to visual perception and visuo-spatial attention impairments, including patients at different symptoms stage. Eleven mTBI patients (mean age 22.8 years) and ten healthy controls participated in the study. Visuo-motor integration of fine motor abilities and form recognition were measured with the Beery-Buktenica Developmental Test of Visual-Motor Integration test, motion perception was evaluated with motion coherence test, critical flicker fusion was measured with Pocket CFF tester. Visuo-spatial was assessed with the Ruff 2 & 7 Selection Attention Test. mTBI patients showed reduced visuo-motor integration, form recognition, and motor deficits as well as visuo-spatial attention impairment, while motion perception and critical flicker fusion were not impaired. These preliminary findings suggest that the temporary brain insults deriving from mTBI compromise fine motor skills, visuomotor integration, form recognition, and visuo-spatial attention. The impairment in visuo-motor coordination was associated with speed in visuo-attention and correlated with symptoms severity while motor ability was correlated with time since concussion. Given the strong correlation between visuomotor coordination and symptom severity, further investigation with a larger sample seems warranted. Since there appeared to be differences in motor skills with respect to symptom stage, further research is needed to investigate symptom profiles associated with visuomotor coordination and fine motor deficits in mTBI patients.

Clinical relevance: Ocular biometry is key to understanding the determinants of ocular development and pathology changes, especially for the thriving myopic population in Asia. Investigating biometric data in highly myopic eyes within a wide age spectrum is therefore of high importance.Background: To report the magnitude of change in spherical equivalent for each unit of change in the ocular biometry parameters in a highly myopic population in China.Methods: Highly myopic patients aged 7 to 70 years were recruited from the Zhongshan Ophthalmic Center, China. Each patient had a cycloplegic refraction and a measurement of ocular biometry.Results: Data from 823 right eyes were available for analysis, with a mean age of 22.7 years and a median spherical equivalent of -8.88 D. Axial length and lens thickness increased with age, while anterior chamber depth (ACD) decreased in older subjects. There was a significant trend of increasing axial length, lens thickness, vitreous chamber depth (VCD) and decreasing ACD and calculated lens power over spherical equivalent quartiles (all p

IMPORTANCE: Many ophthalmology appointments have been converted to telemedicine assessments. The use of a printed vision chart for ophthalmology telemedicine appointments that can be used by people who are excluded from digital testing has yet to be validated. OBJECTIVES: To evaluate the repeatability of visual acuity measured using the Home Acuity Test (HAT) and the agreement between the HAT and the last in-clinic visual acuity. DESIGN, SETTING, AND PARTICIPANTS: This diagnostic study was conducted from May 11 to 22, 2020, among 50 control participants and 100 adult ophthalmology outpatients who reported subjectively stable vision and were attending routine telemedicine clinics. Bland-Altman analysis of corrected visual acuity measured with the HAT was compared with the last measured in-clinic visual acuity on a conventional Early Treatment Diabetic Retinopathy Study logMAR chart. MAIN OUTCOMES AND MEASURES: For control participants, repeatability of the HAT and agreement with standard logMAR visual acuity measurement. For ophthalmology outpatients, agreement with the last recorded in-clinic visual acuity and with the International Classification of Diseases and Related Health Problems, 11th Revision visual impairment category. RESULTS: A total of 50 control participants (33 [66%] women; mean [SD] age, 36.0 [10.8] years) and 100 ophthalmology patients with a wide range of diseases (65 [65%] women; mean [SD] age, 55.3 [22.2] years) were recruited. For control participants, mean (SD) test-retest difference in the HAT line score was −0.012 (0.06) logMAR, with limits of agreement (LOA) between −0.13 and 0.10 logMAR. The mean (SD) difference in visual acuity compared with conventional vision charts was −0.14 (0.14) logMAR (range, −0.4 to 0.18 log MAR) (−7 letters) in controls, with LOA of −0.41 to 0.12 logMAR (−20 to 6 letters). For ophthalmology outpatients, the mean (SD) difference in visual acuity was −0.10 (0.17) logMAR (range, −0.5 to 0.3 logMAR) (1 line on a conventional logMAR sight chart), with the HAT indicating poorer visual acuity than the previous in-clinic test, and LOA of −0.44 to 0.23 logMAR (−22 to 12 letters). There was good agreement in the visual impairment category for ophthalmology outpatients (Cohen κ = 0.77 [95% CI, 0.74-0.81]) and control participants (Cohen κ = 0.88 [95% CI, 0.88-0.88]). CONCLUSIONS AND RELEVANCE: This study suggests that the HAT can be used to measure visual acuity by telephone for a wide range of ophthalmology outpatients with diverse conditions. Test-retest repeatability is relatively high, and agreement in the visual impairment category is good for this sample, supporting the use of printed charts in this context.

Significance This study presents the relationship between distance visual acuity and a range of uncorrected refractive errors, a complex association that is fundamental to clinical eye care and the identification of children needing refractive correction. Purpose This study aimed to analyze data from the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study to describe the relationship between distance uncorrected refractive error and visual acuity in children. Methods Subjects were 2212 children (51.2% female) 6 to 14 years of age (mean ± standard deviation, 10.2 ± 2.1 years) participating in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study between 2000 and 2010. Uncorrected distance visual acuity was measured using a high-contrast projected logMAR chart. Cycloplegic refractive error was measured using the Grand Seiko WR-5100K autorefractor. The ability of logMAR acuity to detect various categories of refractive error was examined using receiver operating characteristic curves. Results Isoacuity curves show that increasing myopic spherical refractive errors, increasing astigmatic refractive errors, or a combination of both reduces distance visual acuity. Visual acuity was reduced by approximately 0.5 minutes of MAR per 0.30 to 0.40 D of spherical refractive error and by approximately 0.5 minutes of MAR per 0.60 to 0.90 D of astigmatism. Higher uncorrected hyperopic refractive error had little effect on distance visual acuity. Receiver operating characteristic curve analysis suggests that a logMAR distance acuity of 0.20 to 0.32 provides the best balance between sensitivity and specificity for detecting refractive errors other than hyperopia. Distance acuity alone was ineffective for detecting hyperopic refractive errors. Conclusions Higher myopic and/or astigmatic refractive errors were associated with predictable reductions in uncorrected distance visual acuity. The reduction in acuity per diopter of cylindrical error was about half that for spherical myopic error. Although distance acuity may be a useful adjunct to the detection of myopic spherocylindrical refractive errors, accommodation presumably prevents acuity from assisting in the detection of hyperopia. Alternate procedures need to be used to detect hyperopia.

IMPORTANCE: There is substantial socioeconomic and individual burden from uncorrected refractive error (URE) and chronic ocular disease. Understanding the association of visual acuity (VA) reduction with URE and the adults most likely to benefit from refraction may help support clinical decision-making in ophthalmologic care and maximize patient outcomes. OBJECTIVES: To assess the magnitude of VA improvement associated with URE among adults under ophthalmic care who obtain low vision rehabilitation (LVR) services and identify the characteristics of the patients who are most likely to experience improvement. DESIGN, SETTING, AND PARTICIPANTS: This retrospective case series assessed patients 20 years or older who were new to the LVR clinics from August 1, 2013, to December 31, 2015, and who had habitual VA between 20/40 and counting fingers (not including) and underwent refraction. Data analysis was performed from April 4, 2018, to December 20, 2019. EXPOSURES: Patient demographics and clinical data, including habitual and refraction VA, refraction, and disease diagnosis. Habitual VA was categorized as mild (VA worse than 20/40 and at least 20/60), moderate (VA worse than 20/60 and better than 20/200), severe (VA 20/200 or worse and better than 20/500), and profound (VA 20/500 or worse) vision impairment (VI). MAIN OUTCOMES AND MEASURES: At least 2-line VA improvement and any VA improvement (≥1-line) by refraction. RESULTS: Among the 2923 patients new to LVR clinics, 1773 (mean [SD] age, 70 [18.2] years; 1069 [60.3%] female) were included in these analyses. The mean habitual VA was 20/100 (mean [SD], 0.67 [0.36] logMAR). At least 2-line improvement was observed in 493 patients (27.8%), and any VA improvement was seen in 1023 patients (57.7%). At least 2-line improvement was observed in 54 patients (34.8%) with corneal disorders and was more likely seen among patients aged 40 to

SIGNIFICANCE Laser refractive surgery procedures are efficacious at correcting myopia, but they result in long-term deterioration of optical quality that affects monocular and binocular visual performance. The study shows that the optical quality of the two eyes needs to be similar to optimize binocular visual performance after surgery. PURPOSE This study aimed to systematically analyze longitudinal changes in optical quality, high- and low-contrast logMAR acuity and random-dot stereoacuity before and after three refractive surgery procedures for correcting myopia. METHODS A total of 106 subjects (laser-assisted in situ keratomileusis, 40; photorefractive keratectomy, 26; small-incision lenticule extraction, 40) with myopia and astigmatism ≤1.5 D participated in this prospective cohort-based study. All aforementioned outcome variables were measured in both eyes pre-operatively and 1 week and 1, 3, and 6 months post-operatively. RESULTS Pre-operative myopic spherical equivalent of refraction (median [25th to 75th interquartile range], -6.4 D [-8.0 to -4.2 D] for laser-assisted in situ keratomileusis, -4.3 D [-5.0 to -3.5 D] for photorefractive keratectomy, -5.5 D [-6.5 to -4.3 D] for small-incision lenticule extraction) was corrected to within ±0.75 D of emmetropia in all cohorts up to 6 months post-operatively (P < .001). Higher-order wavefront aberrations, uncorrected high- and low-contrast logMAR acuity, and stereoacuity all worsened and remained so up to 6 months post-operatively, relative to pre-operative values (P < .001). Stereoacuity worsened with both interocular average and difference in the magnitude of higher-order aberrations, whereas logMAR acuities worsened only with interocular average of these aberrations (r ≥ 0.40; P < .01 for all). CONCLUSIONS Although the refractive surgery procedures tested here correct myopia, they result in a sustained (up to 6 months) loss of optical quality and spatial and depth-related visual functions post-operatively. Both interocular average and difference in the eye's optical quality seem to impair binocular visual functions after refractive surgery for myopia.

Purpose of review This review outlines ophthalmic diagnostic systems, which objectively evaluates the human visual system and its potential beyond that of Snellen acuity. Recent findings Advances in ophthalmic diagnostic systems have allowed for a deeper understanding of the optical principles of the human eye and have created the opportunity to evolve our current standards of vision assessment beyond Snellen acuity charts. Definitive comparative and validation trials will continue to be necessary in order for these advanced diagnostics to gain more widespread acceptance in the specialty, in addition to providing the guidance on the specific indications and utilities. Summary Advancements in wavefront analysis, light scatter measurements, and adaptive optics technologies can provide greater insight into an individual optical system's potential and irregularities. Modalities that test for anterior corneal surface and whole eye aberrations, light scatter and contrast sensitivity can be an excellent educational tool for our patients to help them better understand their visual dysfunction and can prove useful for medical or surgical decision-making.

Purpose In 2019, we described ASTEROID, a new stereotest run on a 3D tablet computer which involves a four-alternative disparity detection task on a dynamic random-dot stereogram. Stereo thresholds measured with ASTEROID were well correlated with, but systematically higher than (by a factor of around 1.5), thresholds measured with previous laboratory stereotests or the Randot Preschool clinical stereotest. We speculated that this might be due to the relatively large, sparse dots used in ASTEROID v0.9. Here, we introduce and test the stereo thresholds and test-repeatability of the new ASTEROID v1.0, which uses precomputed images to allow stereograms made up of much smaller, denser dots. Methods Stereo thresholds and test/retest repeatability were tested and compared between the old and new versions of ASTEROID (n = 75) and the Randot Circles (n = 31) stereotest, in healthy young adults. Results Thresholds on ASTEROID v1.0 are lower (better) than on ASTEROID v0.9 by a factor of 1.4, and do not differ significantly from thresholds on the Randot Circles. Thresholds were roughly log-normally distributed with a mean of 1.54 log10 arcsec (35 arcsec) on ASTEROID v1.0 compared to 1.70 log10 arcsec (50 arcsec) on ASTEROID v0.9. The standard deviation between observers was the same for both versions, 0.32 log10 arcsec, corresponding to a factor of 2 above and below the mean. There was no difference between the versions in their test/retest repeatability, with 95% coefficient of repeatability = 0.46 log10 arcsec (a factor of 2.9 or 1.5 octaves) and a Pearson correlation of 0.8 (comparable to other clinical stereotests). Conclusion The poorer stereo thresholds previously reported with ASTEROID v0.9 appear to have been due to the relatively large, coarse dots and low density used, rather than to some other aspect of the technology. Employing the small dots and high density used in ASTEROID v1.0, thresholds and test/retest repeatability are similar to other clinical stereotests.

High visual acuity is essential for many tasks, from recognizing distant friends to driving a car. While much is known about how the eye’s optics and anatomy contribute to spatial resolution, possible influences from eye movements are rarely considered. Yet humans incessantly move their eyes, and it has long been suggested that oculomotor activity enhances fine pattern vision. Here we examine the role of eye movements in the most common assessment of visual acuity, the Snellen eye chart. By precisely localizing gaze and actively controlling retinal stimulation, we show that fixational behavior improves acuity by more than 0.15 logMAR, at least 2 lines of the Snellen chart. This improvement is achieved by adapting both microsaccades and ocular drifts to precisely position the image on the retina and adjust its motion. These findings show that humans finely tune their fixational eye movements so that they greatly contribute to normal visual acuity., Humans are normally not aware that their eyes are always in motion, even when attempting to maintain steady gaze on a point. Here the authors show that these small eye movements are finely controlled and contribute more than two lines in a standard eye-chart test of visual acuity.

Purpose To assess the influence of capsular tension ring (CTR) on surgical outcomes of toric and multifocal intraocular lenses (IOLs) in eyes at high risk of zonular instability. Methods Fifty-five eyes of 43 patients who had undergone phacoemulsification and IOL implantation were included in the analysis. They had some risk of zonular weakness, such as pseudoexfoliation, shallow anterior chamber, high myopia, and phacodonesis, or were judged to have unstable zonules during surgery. Toric IOL was implanted in 9 eyes with CTR and 22 eyes without CTR, while multifocal IOL was used in 9 eyes with CTR and 15 eyes without CTR. Manifest refraction, refractive astigmatism, visual acuity, and degree of IOL decentration and tilt measured using swept-source anterior segment optical coherence tomography were analyzed. Axis misalignment of toric IOLs were also evaluated. Results In toric IOLs, co-implantation of CTR significantly reduced decentration and axis misalignment of IOL, resulting in better uncorrected and corrected visual acuity after surgery. In multifocal IOLs, combined use of CTR significantly prevented IOL tilt, leading to better intermediate visual acuity. Spherical equivalent and residual astigmatism were not significantly affected by the use of CTR. Conclusions CTR reduces decentration and axis misalignment of toric IOL and tilt of multifocal IOL, achieving improvement of postoperative visual function in eyes with suspected zonular instability.

Purpose: To determine the factors affecting the risk of deterioration and evaluate the refractive error change in patients with fully accommodative esotropia. Methods: Patients diagnosed as having fully accommodative esotropia (esotropic deviation that started before 7 years of age and less than 8 to 10 prism diopters [PD] of esotropia with full hyperopic correction and/or bifocals) were included in this retrospective population-based cohort study. Refractive error changes were recorded. For comparisons, patients were divided into two groups: nondecompensated fully accommodative esotropia group and decompensated fully accommodative esotropia group. Results: Two hundred and twenty-three patients met the inclusion criteria. The mean follow-up time was 5.94 ± 0.31 years (range: 5 to 8 years). The changes in spherical equivalent in the younger than 7 years, 7 to 12 years, and 12 to 17 years groups were statistically significant ( P < .001). The decrease of hypermetropia was 0.13 diopters/year between 7 and 12 years and 0.06 diopters/year between 12 and 17 years. Forty-one of 223 patients (18.4%) discontinued spectacle therapy during the follow-up period. Hyperopic error and presence of amblyopia were lower, whereas visual acuity level and presence of near-distance disparity were higher in the spectacle discontinuation group ( P < .001, .007, .01, and 0.01, respectively). Deterioration of fully accommodative esotropia occurred in 30 of 223 patients (13.5%). Boys were more likely to require strabismus surgery ( P = .32). The mean age at presentation, esotropia angle with and without refractive correction at both near and distance fixation, near distance disparity, and inferior oblique overaction were significantly higher in patients with decompensated fully accommodative esotropia. Conclusions: Hyperopic error increased from the initial level until 7 years of age, followed by a myopic shift thereafter. Few children had resolution of fully accommodative esotropia and could discontinue spectacle therapy. Children with male gender, higher esotropia angle, older age at presentation, near-distance disparity, and inferior oblique overaction experienced a greater deterioration of the fully accommodative esotropia. [ J Pediatr Ophthalmol Strabismus . 2020;57(4):217–223.]

In this paper, novel visual acuity test strategy is proposed. Unlike conventional way, an instructor shows a subject the magnifying image of Landolt ring through the monitor. By adapting multiple reliability verification system using feedback, instructor can get the vision acuity data with higher accuracy and resolution. It can detect at least 5 more distributed vision between representative vision widely known before. As the new system require less than half of the space than before, it is not only more accurate but also efficient.

This study examined the factors affecting corneal curvature change after lateral rectus recession and medial rectus resection surgery in patients with intermittent exotropia. This was a retrospective cross-sectional study in intermittent exotropia patients who underwent rectus resection surgery. The study involved 41 male and 42 female patients (mean age: 9.55 ± 5.03 years, range: 3-28 years). Corneal astigmatism analysis was performed using the Galilei G4 Dual Scheimpflug Analyzer. The values of simulated and ray tracing corneal keratometry (K) of astigmatism, including axis changes, were determined preoperatively and at 1 week and 3 months postoperatively. The factors found to affect corneal curvature change were sex, extent of surgery, and axial length. Simulated and ray tracing changes were significant preoperatively and at 1 week and 3 months after rectus resection surgery (p < 0.05); however, there were no differences in astigmatism (D) at any time. The spherical equivalent had a myopic change after rectus resection surgery with cycloplegic refraction, and in ray tracing mode, flat K was decreased at 1 week from baseline and increased 3 months later. Steep, mean K, and axis increased continuously from baseline to 1 week and 3 months. Astigmatism, in contrast, was increased at 1 week, but decreased at 3 months, with no return to baseline. Univariable linear regression analyses showed that the extent of surgery had an effect on flat K change and that sex had an effect on steep K and axis. Additionally, axial length affected steep K and astigmatism, while age had no effect on any variable. Ray tracing values were significantly different from simulated values. In ray tracing mode, rectus resection surgery may result in astigmatism shifted toward with-the-rule, and myopic changes may be caused by differences in thickness and flexibility of the sclera. Notably, age did not affect any variable.