3,175 results on '"Vision test"'
Search Results
2. Predicción del Síndrome Informático Visual mediante la adicción a videojuegos en estudiantes chinos y españoles.
- Author
-
Lobato Rincón, Lus-Lucio, Medina Sánchez, María Angeles, Huerta Zavala, Pilar, Malos Cámara, Rafael Fabricio, and Vila boa, Ricardo Bernárdez
- Subjects
GAMING disorder ,COVID-19 pandemic ,COMPUTER vision ,CHINESE-speaking students ,LOW vision - Abstract
Copyright of Revista Habanera de Ciencias Médicas is the property of Universidad de Ciencias Medicas de La Habana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
3. Predicción del Síndrome Informático Visual mediante la adicción a videojuegos en estudiantes chinos y españoles
- Author
-
Cathcart Roca, Fidel, Lobato Rincón, Luis Lucio, Medina Sánchez, María Ángeles, Huerta Zavala, Pilar, Matos Cámara, Rafael Fabricio, Bernárdez Vilaboa, Ricardo, Cathcart Roca, Fidel, Lobato Rincón, Luis Lucio, Medina Sánchez, María Ángeles, Huerta Zavala, Pilar, Matos Cámara, Rafael Fabricio, and Bernárdez Vilaboa, Ricardo
- Abstract
El uso de los videojuegos, por la extensión que ha llegado a alcanzar durante la pandemia de la COVID-19, es una variable relevante de estudio, especialmente por sus interacciones con aspectos de la salud mental y visual. Objetivo: predecir el nivel de Síndrome informático visual a partir de un índice optimizado sobre el nivel de adicción en estudiantes universitarios de dos poblaciones: española y china. Material y Métodos: Se administró un cuestionario online con tres instrumentos validados: un cuestionario para evaluar el juego con videojuegos (CHCVI), un cuestionario para evaluar la adicción a los videojuegos (CERV) y un cuestionario para detectar el síndrome visual por ordenador (CSQ). Los tres cuestionarios se aplicaron a una muestra de 253 estudiantes, tanto de universidades chinas como españolas. Para establecer las predicciones, se construyeron índices robustos basados en el análisis factorial de los instrumentos administrados. Finalmente, se aplicó una regresión logística para obtener un modelo matemático útil para predecir el Síndrome Informático Visual. Resultados: Los resultados mostraron un mayor síndrome informático visual y apetito por los videojuegos en los estudiantes españoles, y menores puntuaciones de síndrome informático visual pero una mayor alteración de la vida cotidiana en los estudiantes chinos debido a este tipo de ocio. Además, se comprobó que los estudiantes de la muestra china tenían un menor riesgo de padecer el síndrome informático visual, y que tener mayores niveles de adicción implicaba 1,4 veces más probabilidades de sufrir dicho síndrome. Conclusiones: Los presentes hallazgos demuestran una relación hasta ahora inexplorada entre la adicción a los videojuegos y los síntomas visuales relacionados con el abuso del ocio electrónico., The use of video games, due to the extent that it has reached during the COVID-19 pandemic, is a relevant study variable especially because of its interactions with aspects of mental and visual health. Objective: to predict the occurrence of computer visión syndrome according to the level of addiction to video games in university undergraduates during a particular period of uncertainty due to health and mobility restrictions imposed by governments as a result of the COVID-19 pandemic. Material and Methods: To accomplish this objective, an online questionnaire was administered with three validated instruments: a questionnaire to assess playing video games (CHCVI), a questionnaire to evaluate video games addiction (CERV), and a questionnaire to detect computer vision syndrome (CSQ). The three questionnaires were applied to a sample of 253 students from both Chinese and Spanish universities. To establish the predictions, robust indexes were constructed based on the Factor Analysis of the instruments administered. Finally, logistic regression was applied to predict computer vision syndrome. Results: The results showed greater computer vision síndrome and appetite for video games in Spanish students, and lower computer vision syndrome scores but a greater alteration of daily life in chinese students due to this type of leisure. Moreover, it was found that students from the Chinese sample entailed a lower risk of suffering from computer vision syndrome, and that having higher levels of addiction involved 1,4 times more likelihood of suffering from such syndrome. Conclusions: The present findings demonstrate a previously unexplored relationship between video games addiction and visual symptoms related to screen exposure., Depto. de Estadística y Ciencia de los Datos, Fac. de Estudios Estadísticos, TRUE, pub
- Published
- 2024
4. 'Health Studio' – An Android Application for Health Assessment
- Author
-
Chalumuru, Suresh, Geethika Choudary, P., Itabada, Pranav Souri, Bolla, Vineela, Xhafa, Fatos, Series Editor, Pandian, A. Pasumpon, editor, Palanisamy, Ram, editor, and Ntalianis, Klimis, editor
- Published
- 2020
- Full Text
- View/download PDF
5. Design and validation of a chart‐based measure of the limits of spatial contrast sensitivity.
- Author
-
Adhikari, Prakash, Carter, Drew D, Feigl, Beatrix, and Zele, Andrew J
- Subjects
- *
CONTRAST sensitivity (Vision) , *VISUAL acuity , *SPATIAL resolution , *STATISTICAL reliability , *ADULTS - Abstract
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. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
6. Visual function assessment in stroke patients using a dynamic three-dimensional visual tasks
- Author
-
Megumi Suzuki, Minoru Hoshiyama, Masayuki Yamada, Akiko Maeda, and Eiichi Saitoh
- Subjects
depth perception ,vision test ,visual function ,unilateral neglect ,evaluation ,Medicine (General) ,R5-920 - Abstract
Objectives: Patients with right-hemisphere brain lesions often show unilateral neglect, which causes various difficulties in their daily lives. Disturbances in visuospatial cognition, including unilateral neglect, can be tested quantitatively using questionnaires, yet visuospatial cognition is related not only to the visual system, but also to other cognitive and behavioral functions. Such functions should be assessed by integrative visuo-cognitive tasks. Therefore, the objective of the present study was to clarify visual disturbances in patients with brain lesions using multi-modal visual function tests including three-dimensional and dynamic visual tasks. Methods: We recruited 29 patients, 14 with right- and 15 with left-hemispheric brain lesions, and age-matched control subjects. We conducted depth perception tests and static and active motion detection tests to clarify subjects’ three-dimensional visual recognition performance. Results: There were no significant differences between the patients and controls on any of the visual function tests, except for the static detection test with a mosaic background. However, patients’ total scores on the visual function tests were lower than those of the controls. Discussion: The observed decline in total visual function scores suggests that visual dysfunction caused by stroke should be evaluated not by a single visual function test, but by a series of such tests. We propose that visual functioning in daily life should be evaluated using multi-modal visual function tests.
- Published
- 2017
- Full Text
- View/download PDF
7. Comparison of Structural, Functional, Tonometric, and Visual Acuity Testing for Glaucoma
- Author
-
B. Ramgopal, Rajesh S. Kumar, Caitlin A. Moe, Suria S. Mannil, Sriharsha Nagaraj, Robert L. Stamper, Mahalakshmi V. Rackenchath, Sathi Devi A, Jeremy D. Keenan, Kieran S O'Brien, and Dionna M Wittberg
- Subjects
medicine.medical_specialty ,Intraocular pressure ,Visual acuity ,genetic structures ,business.industry ,Glaucoma ,Diagnostic accuracy ,General Medicine ,medicine.disease ,Likelihood ratios in diagnostic testing ,eye diseases ,Confidence interval ,medicine.anatomical_structure ,Ophthalmology ,medicine ,sense organs ,Vision test ,medicine.symptom ,business ,Optic disc - Abstract
Purpose To determine the diagnostic accuracy of potential screening tests for moderate to advanced glaucoma. Design Prospective diagnostic test accuracy study. Participants The study enrolled a consecutive series of patients aged ≥50 years who presented to a glaucoma clinic in South India without ever having received automated visual field testing. Methods All participants underwent 8 index tests: OCT of the peripapillary retinal nerve fiber layer, optic disc photography, Moorfield’s Motion Displacement Test (MDT), frequency doubling technique perimetry, noncontact tonometry, pneumatonometry, presenting visual acuity, and best-corrected visual acuity. Participants also underwent stereoscopic photographs and Humphrey visual fields, which were used by 2 ophthalmologists to arrive at the reference standard diagnosis of moderate to advanced glaucoma. Main Outcome Measures Sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio. Results A total of 217 people were enrolled; 321 eyes from 180 participants had all tests performed. Of these, 127 eyes (40%) were classified as having moderate to advanced glaucoma. Among the 8 tests, OCT best optimized sensitivity (84%, 95% confidence interval [CI], 76–90) and specificity (75%, 95% CI, 68–81). Moorfield’s Motion Displacement Test was the best perimetric test, with a sensitivity of 91% (95% CI, 85–96) and specificity of 53% (95% CI, 44–61). Pressure and vision tests were not sensitive (e.g., sensitivity of 16%, 95% CI, 9–23 for noncontact tonometry and 23%, 95% CI, 15–31 for best-corrected visual acuity). Moorfield’s Motion Displacement Test identified 16 of 127 eyes (13%) with glaucoma that were not captured by OCT, but also had false-positive results in 65 of 194 eyes (34%) without glaucoma that OCT correctly classified as negative. Conclusions OCT had moderate sensitivity and fair specificity for diagnosing moderate to advanced glaucoma and should be prioritized during an initial assessment for glaucoma.
- Published
- 2022
8. Development of allelic discrimination assay to detect Mediterranean G6PD mutation and its linked inheritance with normal vision and/colorblindness loci for 4 generations among Egyptian and Emirati families
- Author
-
Lina Maloukh, Amin Akhondi, Alagappan Kumarappan, Fatma Gomma, T. V. Rajya Lakshmi, Houssam El-Din El-Wakil, and Fatima Al-Kamali
- Subjects
0106 biological sciences ,0301 basic medicine ,congenital, hereditary, and neonatal diseases and abnormalities ,Emirati ,QH301-705.5 ,Locus (genetics) ,Biology ,01 natural sciences ,Deuteranopia ,Mediterranean G6PD ,03 medical and health sciences ,symbols.namesake ,Polymorphism (computer science) ,hemic and lymphatic diseases ,parasitic diseases ,Vision test ,Egyptian ,Biology (General) ,Gene ,Sanger sequencing ,Genetics ,c563T ,nutritional and metabolic diseases ,Phenotype ,030104 developmental biology ,Pedigree analysis and deuteranopia ,symbols ,Epistasis ,Original Article ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
G6PD deficiency c563T is the most common inherent blood disease among the Mediterranean populations and its molecular diagnosis is critical as the enzyme assay fails for heterozygous individuals. The purpose of the study is to estimate the ubiquity of the heterozygous G6PD Med (c563T) variants among Egyptians and UAE nationals living in Dubai. We validated two molecular methods, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and qPCR allelic discrimination assay for detection of G6PD Med variants. Among 100 screened individuals, G6PD c563T variants are 30% of whom 15% are carriers. Sanger sequencing validated the qPCR discrimination assays. In search of a phenotypic marker to detect G6PD heterozygous variants, inheritance of G6PD locus and red-green color vision genes is studied in 1 Egyptian and 2 Emirati families. Among the 3 families, G6PD is polymorphic, displaying 4 phenotypes: in phenotype-1, person is normal, in phenotype-2 the person has no G6PD deficiency but with deuteranopia/deuteranomaly, in phenotype-3 the person is G6PD Med variant with deuteranopia/deuteranomaly and in phenotype 4 the person is G6PD Med variant has normal vision. Based on the molecular analysis of G6PD and Ishihara vision test it can be concluded that the two mutations at the two loci arose independent of each other without any interaction (epistatic effect) between them. Following the pedigree analysis of the two genes for 4 generations it is presumed that it is infeasible to use “deuteranopia /deuteranomaly” as a phenotypic marker to detect G6PD c563T heterozygous individuals among the Egyptian populations.
- Published
- 2021
9. Disparities in Regular Health Care Utilisation in Europe
- Author
-
Sirven, Nicolas, Or, Zeynep, Börsch-Supan, Axel, editor, Brandt, Martina, editor, Hank, Karsten, editor, and Schröder, Mathis, editor
- Published
- 2011
- Full Text
- View/download PDF
10. Effects of chronic smoking on color vision in young subjects
- Author
-
Hatice Arda, G Ertugrul Mirza, Osman A Polat, Sarper Karakucuk, and Koray Gumus
- Subjects
cigarette smoking ,color vision defect ,vision test ,Ophthalmology ,RE1-994 - Abstract
AIM: To evaluate the effects of chronic smoking on color vision in young subjects. METHODS: This study included 91 smokers and 88 non-smokers (a total of 179 volunteers) without any ophthalmologic and systemical disorders. The subjects were between 18-40 years of age with a best corrected visual acuity (BCVA) of 20/20, normal anterior and posterior segment examinations and normal intraocular pressure. The color vision of the subjects were evaluated with Farnsworth-Munsell 100 Hue test (FMHT). The total error scores and axis calculation were performed for each subject and the results correlated. RESULTS: Mean age and the standard deviation was 28±5y in the smokers group, and 26.7±5.5y in the control group (P=0.101). Sex distribution was similar in the two groups (P=0.365). There was no significant correlation between age and FMHT total error scores (P=0.069). Median of FMHT total error scores of smokers and non-smokers were 65 and 50.50, respectively. FMHT total error scores was found significantly higher in smokers than non-smokers (P=0.004). There was no statisticaly significant difference between smoker and non-smoker groups with respect to axis ratio calculation (P=0.611). There was no significant correlation with FMHT total error scores with neither smoking duration nor number of cigarettes smoked per day (P=0.405, P=0.454, respectively). CONCLUSION: This study suggested that chronic smoking affects the color vision of young smokers but this may not be sector selective.
- Published
- 2015
- Full Text
- View/download PDF
11. Assessment of Visual Function and Performance in Paralympic Judo for Athletes with Vision Impairment
- Author
-
David L. Mann, Rianne H. J. C. Ravensbergen, Kai Krabben, Daniel Fortin-Guichard, Dominic Orth, Geert J.P. Savelsbergh, Motor learning & Performance, AMS - Sports, and IBBA
- Subjects
medicine.medical_specialty ,Visual acuity ,SDG 16 - Peace ,genetic structures ,media_common.quotation_subject ,Decision tree ,Vision Disorders ,Audiology ,Athletic Performance ,medicine ,Contrast (vision) ,Humans ,Vision test ,Motion perception ,Vision, Ocular ,media_common ,Visual search ,biology ,Athletes ,SDG 16 - Peace, Justice and Strong Institutions ,biology.organism_classification ,eye diseases ,Justice and Strong Institutions ,Ophthalmology ,medicine.symptom ,Psychology ,Depth perception ,Martial Arts ,Optometry - Abstract
SIGNIFICANCE Paralympic judo currently requires all athletes to compete against each other in one class irrespective of their level of vision impairment (VI). Recent evidence suggests that multiple classes are required to enhance fairness, yet it remains unclear how many classes are necessary and what vision tests should be used to define those classes. PURPOSE The aim of this study was to quantify the relationship between vision and performance in judo for individuals with VI. The results were expected to inform the development of evidence-based criteria to structure Paralympic judo competition. METHODS The visual function of 53 elite VI judokas was assessed using a test battery that included tests of visual acuity (VA), contrast sensitivity, light sensitivity, depth perception, motion perception, visual search, and central visual field. Performance was assessed by measuring the ratio of fights won across all competitions the participants took part in in the 2 years before and after vision testing. Pearson correlation coefficients and decision tree analyses were used to determine the relationship between vision and performance. Partial correlations were also conducted to determine the unique ability of each measure of visual function to predict judo performance. RESULTS Visual acuity was the best predictor of judo performance and remained the only visual function related to performance when controlling for correlations between VA and other visual functions. Decision tree analyses suggested to split athletes into two groups for more legitimate competition, using a cutoff point around 2.6 logMAR. Within each of the two resulting subgroups, no correlations remained between any of the visual functions and performance. CONCLUSIONS The results of this study suggest that VI judo competition should be split into separate categories for partially sighted and functionally blind athletes. The inclusion of visual functions in addition to VA does not improve the ability to predict performance in VI judo.
- Published
- 2021
12. Comparing a Home Vision Self-Assessment Test to Office-Based Snellen Visual Acuity
- Author
-
Jonathan Z. Li, Julie M. Schallhorn, Catherine Q. Sun, and Tiffany A Chen
- Subjects
Self-assessment ,medicine.medical_specialty ,Visual acuity ,genetic structures ,Eye ,Primary outcome ,Clinical Research ,Opthalmology and Optometry ,Ophthalmology ,medicine ,vision screening ,Vision test ,Prospective cohort study ,Eye Disease and Disorders of Vision ,Original Research ,Office based ,business.industry ,Neurosciences ,home vision test ,Clinical Ophthalmology ,Health Services ,Snellen visual acuity ,eye diseases ,Test (assessment) ,telemedicine ,tele-ophthalmology ,medicine.symptom ,business - Abstract
Tiffany A Chen,1 Jonathan Li,1 Julie M Schallhorn,1,2 Catherine Q Sun1,2 1Department of Ophthalmology, University of California San Francisco, San Francisco, CA, USA; 2F.I Proctor Foundation, University of California San Francisco, San Francisco, CA, USACorrespondence: Catherine Q SunF.I. Proctor Foundation, University of California San Francisco, Box 0944, 490 Illinois Street, San Francisco, CA, 94143, USAEmail catherine.sun@ucsf.eduPurpose: To evaluate the agreement of a home vision screening test compared to standard in-office technician-measured Snellen visual acuity to allow for remote screening and triaging of patients.Patients and Methods: In this prospective study, English-speaking patients with in-office ophthalmology appointments from May to August 2020 and visual acuity better than 20/125 were asked to complete a home vision test one week before their scheduled in-office appointment. The home vision test was a modified ETDRS chart displayed in a PDF document that could be printed or viewed on a monitor. The primary outcome was the mean difference between office-based and home visual acuity.Results: Eighty-two eyes of 45 patients were included in the study with 45 study eyes analyzed. The mean difference between office-based and home visual acuity was â 0.02 logMAR (SD 0.15, P=0.28) among study eyes. Of these eyes, 91% demonstrated agreement between the two methods within 0.2 logMAR of the mean difference, and 60% had agreement within 0.1 logMAR of the mean difference. There were no significant demographic or ocular risk factors leading to a greater difference between the tests.Conclusion: There was good agreement between the home and in-office Snellen tests for patients with vision better than 20/125. The home vision test can be used to remotely determine if there is a significant vision change of > 0.2 logMAR or approximately 2 lines of visual acuity.Keywords: telemedicine, tele-ophthalmology, home vision test, vision screening
- Published
- 2021
13. Design of Low Cost Automated Vision Screening Test for Awarding Driving License
- Author
-
Ganesan Kaliyaperumal and D Shalini
- Subjects
color blindness ,contrast sensitivity test ,motor vehicle act ,visual acuity ,vision test ,Medicine - Published
- 2017
- Full Text
- View/download PDF
14. Community-Based Hearing and Vision Screening in Schools in Low-Income Communities Using Mobile Health Technologies
- Author
-
De Wet Swanepoel, Hannah Kuper, Jeannie van der Linde, Renate Olinger, and Michelle Manus
- Subjects
Male ,Linguistics and Language ,medicine.medical_specialty ,Speech-Language Pathology ,Visual acuity ,medicine.medical_treatment ,MEDLINE ,Audiology ,Language and Linguistics ,South Africa ,03 medical and health sciences ,Speech and Hearing ,Vision Screening ,0302 clinical medicine ,Audiometry ,Hearing ,Health care ,medicine ,Humans ,Mass Screening ,030212 general & internal medicine ,Vision test ,Child ,030223 otorhinolaryngology ,Poverty ,Referral and Consultation ,mHealth ,Schools ,Rehabilitation ,medicine.diagnostic_test ,business.industry ,Hearing Tests ,Health technology ,Telemedicine ,Early Diagnosis ,Child, Preschool ,Calibration ,Female ,Smartphone ,medicine.symptom ,Psychology ,business ,Delivery of Health Care - Abstract
Introduction Globally, more than 50 million children have hearing or vision loss. Most of these sensory losses are identified late due to a lack of systematic screening, making treatment and rehabilitation less effective. Mobile health (mHealth), which is the use of smartphones or wireless devices in health care, can improve access to screening services. mHealth technologies allow lay health workers (LHWs) to provide hearing and vision screening in communities. Purpose The aim of the study was to evaluate a hearing and vision school screening program facilitated by LHWs using smartphone applications in a low-income community in South Africa. Method Three LHWs were trained to provide dual sensory screening using smartphone-based applications. The hearScreen app with calibrated headphones was used to conduct screening audiometry, and the Peek Acuity app was used for visual acuity screening. Schools were selected from low-income communities (Gauteng, South Africa), and children aged between 4 and 9 years received hearing and vision screening. Screening outcomes, associated variables, and program costs were evaluated. Results A total of 4,888 and 4,933 participants received hearing and vision screening, respectively. Overall, 1.6% of participants failed the hearing screening, and 3.6% failed visual acuity screening. Logistic regression showed that female participants were more likely to pass hearing screening ( OR = 1.61, 95% CI [1.11, 2.54]), while older children were less likely to pass visual acuity screening ( OR = 0.87, 95% CI [0.79, 0.96]). A third (32.5%) of referred cases followed up for air-conduction threshold audiometry, and one in four (25.1%) followed up for diagnostic vision testing. A high proportion of these cases were confirmed to have hearing (73.1%, 19/26) or vision loss (57.8%, 26/45). Conclusions mHealth technologies can enable LHWs to identify school-age children with hearing and/or vision loss in low-income communities. This approach allows for low-cost, scalable models for early detection of sensory losses that can affect academic performance.
- Published
- 2021
15. Diagnostic accuracy of the Parr vision test, single crowded Lea symbols and Spot vision screener for vision screening of preschool children aged 4–5 years in Aotearoa/New Zealand
- Author
-
Nicola Anstice, Joanna Black, Rebecca Findlay, Carol Chelimo, Lucy Goodman, and Cameron C. Grant
- Subjects
Refractive error ,Visual acuity ,genetic structures ,Ocular Pathology ,Visual Acuity ,Diagnostic accuracy ,Astigmatism ,Refraction, Ocular ,03 medical and health sciences ,Vision Screening ,0302 clinical medicine ,Humans ,Medicine ,Vision test ,Schools ,business.industry ,Incidence ,Reproducibility of Results ,Refractive Errors ,medicine.disease ,eye diseases ,Sensory Systems ,Test (assessment) ,Comprehensive eye examination ,Ophthalmology ,Cross-Sectional Studies ,Child, Preschool ,030221 ophthalmology & optometry ,Optometry ,medicine.symptom ,business ,030217 neurology & neurosurgery ,New Zealand - Abstract
Purpose Preschool children in New Zealand undergo vision screening to detect amblyopia at 4-5 years of age. The current test, the Parr vision test, does not meet international visual acuity chart guidelines and has not been validated against other commonly used paediatric vision tests. New Zealand vision screening protocols are also not targeted for detecting other eye conditions such as uncorrected refractive error, which may affect school performance. We compared the Parr vision test with the single crowded Lea symbols and the Spot vision screener for detecting ocular pathology, refractive error and amblyopic risk factors in preschool children. Methods A cross-sectional diagnostic accuracy study recruited children aged 4-5 years via convenience sampling from the University of Auckland Optometry Clinic and through primary schools in Auckland, New Zealand. Participants received vision screening with the three different instruments administered by a lay screener. Comprehensive eye examinations were completed by a paediatric optometrist to determine the presence of vision disorders. Results Of 197 children who received a comprehensive eye examination, 14 (7.1%) had amblyopic risk factors and 43 (21.8%) had significant refractive error (15.7% with astigmatism, 9.1% with hyperopia). The sensitivity for detecting any ocular condition did not differ significantly between the tests (50.0% for Parr, 43.5% for Lea, 42.5% for Spot). Specificity was significantly lower for the Parr vision test (80.8%) than for the Lea symbols (93.4%) and Spot vision screener (98.0%). Adding the Spot vision screener to measurements of visual acuity significantly improved sensitivity in detecting any ocular condition with the Parr vision test (67.5% for Parr/Spot vs 50% for Parr alone), but not with the Lea symbols (52.5% for Lea/Spot vs 43.5% for Lea alone). Conclusion The sensitivity of the Parr vision test for detecting ocular conditions in preschool children does not vary significantly from that achieved by the Lea symbols or the Spot vision screener. However, current New Zealand vision screening protocols could be improved by expanding the target conditions to include significant refractive error and incorporating the use of the Spot vision screener to increase the accuracy with which children with refractive error are identified. Future research should include longitudinal studies to determine the effect of preschool vision screening on later ocular and academic outcomes.
- Published
- 2021
16. Rotational stability of toric intraocular lenses with a newly modified capsular tension ring
- Author
-
Nick Mamalis, Sneha Bontu, Liliana Werner, Sean Kennedy, Bonnie An Henderson, and John Zdral
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Lens Capsule, Crystalline ,Intraocular lens ,Prosthesis Design ,Salt lake ,03 medical and health sciences ,0302 clinical medicine ,Lens Implantation, Intraocular ,Ophthalmology ,medicine ,Humans ,Vision test ,Mathematics ,Lenses, Intraocular ,Phacoemulsification ,Vision Tests ,Sensory Systems ,Intraocular lenses ,Capsular bag ,030221 ophthalmology & optometry ,Surgery ,Modified capsular tension ring ,Rotational stability ,030217 neurology & neurosurgery - Abstract
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.
- Published
- 2021
17. Real-time communicative perspective taking in younger and older adults
- Author
-
Raheleh Saryazdi and Craig G. Chambers
- Subjects
Adult ,Aging ,Linguistics and Language ,Visual perception ,Adolescent ,Theory of Mind ,Short-term memory ,Experimental and Cognitive Psychology ,050105 experimental psychology ,Language and Linguistics ,Young Adult ,Mentalization ,Theory of mind ,Humans ,0501 psychology and cognitive sciences ,Vision test ,Aged ,Aged, 80 and over ,Verbal Behavior ,Working memory ,Communication ,05 social sciences ,Perspective (graphical) ,Common ground ,Cognition ,Middle Aged ,Knowledge ,Memory, Short-Term ,Female ,Psychology ,Cognitive psychology - Abstract
One core question in studies of language processing is the extent to which interlocutors engage in real-time communicative perspective-taking. Current evidence suggests that both children and young adult listeners are able to draw on common ground (shared knowledge) to guide referential interpretation. However, less is known about older listeners, who are often described as experiencing age-related cognitive declines that could affect their capacity to integrate perspective cues online. In the present study, we examined the extent to which younger and older listeners used common ground to guide the interpretation of temporarily ambiguous descriptions. Participants followed instructions from a Director to click on displayed objects. The target object (e.g., hat with blue feathers) was accompanied by a competitor (e.g., hat with pink feathers) or a control object (e.g., stapler). We manipulated whether the competitor/control was mutually visible (common ground) or not (privileged ground). The results revealed that, although listeners used perspective information to differentiate the target from the competitor in the common ground condition, this pattern was notably weaker in older adults. Whereas measures of executive function showed significant group differences in inhibitory control and working memory, no differences were found in theory of mind. Thus, age-related changes in communicative perspective-taking are not likely due to general declines in mentalizing ability. Furthermore, strict screening criteria for vision and hearing ability allowed us to rule out explanations involving age-related sensory decline. Together, the results advance our understanding of how younger and older adults integrate common ground during real-time referential processing. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
- Published
- 2021
18. Visual assessment of commercial drivers in the South West Region of Cameroon
- Author
-
Nicholas Tendongfor, Eleanor Ngwe Nche, Doris Ako Ayuk, Jacob Pe'er, Alain Chichom-Mefire, and Brice Nguedia Vofo
- Subjects
Adult ,Male ,Automobile Driving ,Visual acuity ,genetic structures ,030231 tropical medicine ,03 medical and health sciences ,0302 clinical medicine ,lcsh:Ophthalmology ,0502 economics and business ,Visual assessment ,Humans ,Medicine ,Statistical analysis ,Vision test ,Cameroon ,Road traffic ,Road traffic crashes ,Snellen chart ,050210 logistics & transportation ,business.industry ,Vision Tests ,Incidence (epidemiology) ,05 social sciences ,Accidents, Traffic ,Mean age ,General Medicine ,Middle Aged ,eye diseases ,Ophthalmology ,Cross-Sectional Studies ,lcsh:RE1-994 ,Female ,medicine.symptom ,business ,Research Article ,Demography ,Driving - Abstract
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.
- Published
- 2021
19. Clinical and Pathologic Presentation of Primary Ocular Surface Tumors among Zambians
- Author
-
Charles E. Wood, John T. West, Stepfanie N. Siyumbwa, Guobin Kang, Trevor Kaile, Peter Julius, Phyllis Moonga, Fred Maate, and Peter C. Angeletti
- Subjects
medicine.medical_specialty ,HIV Positivity ,business.industry ,Buccal swab ,Fungating lesion ,medicine.disease ,Dermatology ,03 medical and health sciences ,0302 clinical medicine ,Keratinizing Squamous Cell Carcinoma ,Interquartile range ,030220 oncology & carcinogenesis ,030221 ophthalmology & optometry ,medicine ,Tears ,Vision test ,business ,General Nursing ,Spindle cell carcinoma ,Research Article - Abstract
Aim: This study aimed to characterize the clinical and pathologic presentation of ocular surface tumors (OSTs) and to more precisely differentiate the grades of ocular surface squamous neoplasia (OSSN) and benign lesions among Zambians. Methods: Two-hundred sixty-five Zambian patients presenting with ocular surface growths, suspicious for OSSN, were recruited between November 2017 and November 2019 to a cross-sectional study to investigate their lesions. Sociodemographic data were collected, HIV infection status and vision tests were performed, and lesions were measured and documented. Lesions >2 mm in diameter were excised and sent for pathology analysis. In addition to the biopsies, tears, blood, and buccal swabs were collected. CD4+ T-cell counts were measured by flow cytometry. Lesions were classified according to the WHO guidelines. χ2 and bivariate correlations were used to analyze variable associations and strengths with phi/Cramer’s V and correlation coefficients, respectively. Binary logistics was used to adjust for covariance. Results: In this study, 68.3% of the participants were found to be HIV positive. The most frequent diagnoses were invasive OSSN (45.3%), preinvasive OSSN (29.1%), and pterygium (22.6%). Invasive OSSN comprised keratinizing squamous cell carcinoma (SCC) (87.5%), basaloid SCC (3.3%), and spindle cell carcinoma (3.3%). Unusual carcinomas, not described previously, included hybrid SCC (5.0%) and acantholytic SCC (0.8%). Invasive OSSN had advanced tumor (T3/T4) staging (93.3%) at diagnosis. Lymphadenopathy was rare (2.3%), and metastasis was absent. Patients were mostly female (59.2%). Median age was 36 (interquartile ranges 33–41) years (ranges 18–81). Patients with invasive OSSN were more likely to present with pain (p = 0.007), redness (p = 0.034), excessive tearing (p = 0.0001), discharge (p = 0.011), bleeding (p = 0.007), reduced vision (p = 0.0001), fungating lesion (p = 0.001), and blindness (p = 0.005); location at temporal limbus (p = 0.0001), inferior limbus (p = 0.0001), or circumlimbal (p = 0.001); and extension to cornea (p = 0.006) and forniceal palpebral conjunctiva (p = 0.001). Invasive OSSN was associated with any smoking habit and alcohol consumption (p = 0.04 and 0.03, respectively). HIV positivity was strongly associated with OSSN (74.6% OSSN vs. 49.3% benign lesions; p = 0.0001; phi: 0.237 [p = 0.0001]). Conclusion: OSTs are very common in Zambia and are strongly associated with HIV coinfection. Patients with OSSN were more likely to be HIV positive than those with pterygia. Despite the commonality of OSTs in sub-Saharan Africa, these cancers have historically been poorly characterized.
- Published
- 2021
20. Delving Into the Visual System in the AMA Guides, Fifth Edition
- Author
-
Daniel C. Schainholz
- Subjects
Visual acuity ,Blindness ,Visual impairment ,medicine ,Optometry ,Vision test ,medicine.symptom ,medicine.disease - Abstract
The assessment of visual impairment using the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fifth Edition, requires a thoughtful ophthalmologic evaluation and careful application of the functional vision tests and arithmetic criteria provided in Chapter 12, The Visual System, and other chapters, as applicable. The interpolation of the multiple dimensions of the visual system into the enumeration of a single impairment percentage may involve complex mathematical manipulations. Properly enumerated, the value can be utilized rigorously in impairment evaluations, functional evaluations, and even for academic research.
- Published
- 2021
21. An Analysis of Data Collection Tools Used When Completing Functional Vision Assessments
- Author
-
Justin T. Kaiser and Tina S. Herzberg
- Subjects
Ophthalmology ,Visual perception ,Visual acuity ,Data collection ,Functional vision ,Orientation (computer vision) ,Rehabilitation ,medicine ,Data analysis ,Vision test ,medicine.symptom ,Psychology ,Cognitive psychology - Abstract
Introduction: This study analyzed 39 data collection tools used by teachers of students with visual impairments when completing functional vision assessments (FVAs). Methods: In 2017, teachers of students with visual impairments submitted data collection tools used in the FVA process. These tools were then compared with the 23 FVA components suggested by two established resources, Erin and Paul and D’Andrea and Farrenkopf. Results: The most commonly assessed skills and abilities were near visual acuity, distance visual acuity, and color perception. Only five of the submitted data collection tools contained at least 80% of the FVA components identified by the established resources. Fewer than 25% of the tools incorporated an orientation and mobility (O&M) screening. Discussion: There was considerable variation in the background information, medical data, and visual skills information that was collected. Variability in the data collected during the FVA process may impact a teacher’s recommendations, including referrals for specialized evaluations such as O&M and clinical low vision evaluations. Implications for practitioners: Since FVA reports are used by Individualized Education Program teams, it is essential that data collection tools used during the assessment process are complete and address key areas such as near visual acuity and color perception. Teachers should carefully review their tools to determine whether the data collected are sufficient to make informed recommendations regarding accommodations, goals, and referrals. If the data collected are not sufficient, then the tools should be revised or additional data should be collected.
- Published
- 2021
22. Relationship among standard vision tests, quality of life, and ability to do daily activities in patients with glaucoma
- Author
-
N Sujatha, Smita Narayan, Neethu Pradeep, V Sudha, and Sinumol Thulaseedharan
- Subjects
Intraocular pressure ,medicine.medical_specialty ,Visual acuity ,Activities of daily living ,genetic structures ,media_common.quotation_subject ,Glaucoma ,hodapp–parrish–anderson ,Quality of life ,Gonioscopy ,Medicine ,Contrast (vision) ,Vision test ,media_common ,contrast sensitivity ,disc damage likelihood scale ,medicine.diagnostic_test ,business.industry ,General Medicine ,RE1-994 ,medicine.disease ,stereopsis ,humanities ,eye diseases ,Ophthalmology ,glaucoma ,quality of life ,Physical therapy ,sense organs ,medicine.symptom ,business ,assessment of disability related to vision ,visual functioning questionnaire-25 - Abstract
Background and Objectives: (1) To assess the quality of life (QoL) in patients with glaucoma by (a) clinical assessment, (b) subjective (Visual Functioning Questionnaire-25 [VFQ-25]), and (c) objective (Assessment of Disability Related to Vision [ADREV]) tests and (2) to find out the relationship between glaucoma stages and QoL. Materials and Methods: This cross-sectional study includes 100 patients attending the glaucoma clinic of a tertiary institution in Kerala. Best-corrected visual acuity, baseline intraocular pressure, slit-lamp and fundus examination, gonioscopy, and visual field examination were carried out. Patients were categorized as early, moderate, and advanced on the basis of disc damage likelihood scale (DDLS) and modified Hodapp–Parrish–Anderson criteria. QoL was assessed subjectively using VFQ-25 and objectively by ADREV test by assessing the ability to perform activities of daily living. Contrast sensitivity and stereopsis were the other parameters assessed. Results: Of the 100 patients, 50 (50%) were POAG, 46 (46%) were PACG, and 4 were secondary glaucoma. Based on the DDLS and Anderson criteria, there were 33 early, 34 moderate, and 33 advanced glaucoma cases. The mean ADREV/VFQ scores were as follows: early, 56.9/81.1; moderate, 54.9/75; and advanced, 45.8/52.6. In ADREV tasks, the lowest mean score was for motion detection (5.1) and maximum score was for ambulation (6.1) in the study population. Patients with advanced glaucoma have difficulty in detecting motion (4.1), recognizing street signs (4.3), and color matching (4.8). Stereopsis was seen in 60% of patients with early, 29% of moderate, and 6% of advanced glaucoma. Contrast sensitivity was also reduced with glaucoma progression. Conclusion: ADREV (objective) scores correlate significantly with VFQ (subjective) scores in all the three categories of glaucoma. ADREV (objective test) scores correlate better with the severity and stages of glaucoma and degree of impairment patients experience than VFQ-25 (subjective test). With respect to QoL, patients with glaucoma faced difficulty in performing fine tasks. However, even advanced glaucoma cases were able to carry out their daily activities without much help. Stereopsis and contrast sensitivity were the most affected with advancement of disease.
- Published
- 2021
23. The Effect of Night Glare on Myopia
- Author
-
Sang-Ho Park and In-Chul Jeon
- Subjects
medicine.medical_specialty ,Visual acuity ,genetic structures ,business.industry ,Mesopic vision ,media_common.quotation_subject ,Glare (vision) ,Adaptation (eye) ,eye diseases ,Pupil ,LogMAR chart ,Ophthalmology ,Contrast (vision) ,Medicine ,sense organs ,Vision test ,medicine.symptom ,business ,media_common - Abstract
Purpose : This study is to investigate the effect of night glare on myopia.Methods : Forty eight myopic eyes aged 20 to 30 year old were under the indoor illumination 1 lx or less for 5 minutes for the mesopic adaptation. Subjects were grouped by the equivalent spherical refraction -3.25 D. The group 1 with the refraction under -3.25 D and the group 2 with over -3.25 D were compared and analyzed. Two 100 Watt bulbs were placed by the side of the target whose illuminance at the position of subject's pupil was measured. The disability glare (contrast visual acuity and contrast sensitivity) was measured at 2, 5, and 10 lx and the discomfort glare was quantified by Deboer glare scale. The contrast acuity was measured by Reverse- Contrast chart at 100%, 25% and 10% of contrast LogMAR chart and the contrast sensitivity using the iPad program Clinic CSF 2.0 was measured at 3, 6, 12 and 18 cycles per degree.Results : The contrast acuity and contrast sensitivity of disability glare were both high in the group 1. The contrast acuity showed a significant difference after glare occurred (p 0.05).Conclusion : Considering the trend of higher nighttime activity in Korea, it is thought that not only a standard vision test for the night and the prescription to intervene the glare is needed regardless of age.
- Published
- 2020
24. Topical Review: Causes of Refractive Error After Silicone-oil Removal Combined with Cataract Surgery
- Author
-
Fu-Qiang Li, Song-Tian Che, Jinsong Zhao, Zhi-Min Shu, and Chen-Li Shan
- Subjects
medicine.medical_specialty ,Refractive error ,genetic structures ,Anterior Chamber ,medicine.medical_treatment ,Optical power ,Cataract Extraction ,Endotamponade ,Suction ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Lens Implantation, Intraocular ,Ophthalmology ,medicine ,Humans ,Silicone Oils ,Vision test ,business.industry ,Vision Tests ,Axial length ,Cataract surgery ,Refractive Errors ,medicine.disease ,eye diseases ,Silicone oil ,Axial Length, Eye ,chemistry ,030221 ophthalmology & optometry ,Intraocular lens power calculation ,business ,030217 neurology & neurosurgery ,Optometry - Abstract
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.
- Published
- 2020
25. Evidence-based Classification in Track Athletics for Athletes with a Vision Impairment
- Author
-
Franziska Zenk, David L. Mann, Helen Croxall, Peter M. Allen, Rianne H. J. C. Ravensbergen, Ashley S. Brooks, Rebecca Dolan, Motor learning & Performance, IBBA, and AMS - Sports
- Subjects
Evidence-based practice ,Delphi Technique ,Applied psychology ,Delphi method ,Vision Disorders ,Visual Acuity ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Social class ,03 medical and health sciences ,0302 clinical medicine ,Misrepresentation ,Humans ,Disabled Persons ,Vision test ,computer.programming_language ,biology ,Athletes ,Individual sport ,biology.organism_classification ,Ophthalmology ,Evidence-Based Practice ,030221 ophthalmology & optometry ,Visual Fields ,Psychology ,computer ,030217 neurology & neurosurgery ,Delphi ,Psychomotor Performance ,Optometry ,Sports - Abstract
SIGNIFICANCE:\ud \ud The Delphi analysis presented here highlights the need for a sport-specific evidence-based classification system for track athletics for athletes with a vision impairment (VI). This system may differ for different race distances. Further research is required to develop a useful test battery of vision tests for classification. The issue of intentional misrepresentation during classification needs particular attention.\ud \ud PURPOSE:\ud \ud At present, athletes with VI are placed into competition classes developed on the basis of legal definitions of VI. The International Paralympic Committee Athlete Classification Code states that all sports should have their own classification system designed to reflect the (visual) demands of that individual sport. This project gathered expert opinion on the specific requirements for an evidence-based sport-specific classification system for VI track athletics and to identify any particular issues within track athletics that require further research into their impact on sport performance.\ud \ud METHODS:\ud \ud A three-round Delphi review was conducted with a panel of 17 people with expertise in VI track athletics.\ud \ud RESULTS:\ud \ud The panel agreed that the current classification system in VI track athletics does not completely minimize the impact of impairment on competition outcome, highlighting the need for improvements. There was clear agreement that the existing measures of vision may fail to adequately reflect the type of vision loss that would impact running performance, with additional measures required. Intentional misrepresentation, where athletes “cheat” on classification tests, remains a serious concern.\ud \ud CONCLUSIONS:\ud \ud The panel has identified measures of vision and performance that will inform the development of an evidence-based classification system by better understanding the relationship between VI and performance in track athletics. Issues such as the use of guides and whether the current class system was equitable gave rise to differing opinions within the panel, with these varying across the different running distances.
- Published
- 2020
26. Building Consensus about the Functional Vision Assessment Process: A Delphi Study
- Author
-
L. Penny Rosenblum, Tina S. Herzberg, and Justin T. Kaiser
- Subjects
Functional vision ,Process (engineering) ,Rehabilitation ,Visual impairment ,Applied psychology ,Delphi method ,Field (computer science) ,Ophthalmology ,Individualized Education Program ,medicine ,Vision test ,medicine.symptom ,Set (psychology) ,Psychology - Abstract
Introduction: Within the field of visual impairment, there is no set of standards that guide teachers of students with visual impairments as they conduct, report, and share functional vision assessment (FVA) results with other educational team members, and university instructors vary in how they teach the assessment process to preservice teachers. Methods: In parallel, a group of teachers of students with visual impairments and a group of university instructors completed three rounds of a Delphi study. After providing background information in Round 1, they rated 84 statements about the FVA process. The level for consensus was set at 80%. Results: Of the 84 statements, consensus was reached for 45 statements regarding the level of importance by both groups. Participants rated 11 of 22 visual skills (e.g., near acuity, distance acuity) as extremely important to include in the FVA process. Discussion: There continues to be a need to build consensus on when FVAs should be conducted, what visual skills should be included when conducting them, what should be included in reports, and with whom assessment information should be shared. The importance of conducting such assessments for all students, including students under the age of 5 years and those with additional disabilities, needs to be recognized by the field of visual impairment. Implications for practitioners: University personnel need to work together to develop consistent curricula that focuses on the FVA process. Future studies that examine the FVA practices of individual teachers are necessary.
- Published
- 2020
27. The Use of Oral Midazolam to Facilitate the Ophthalmic Examination of Children with Autism and Developmental Disorders
- Author
-
K. A. J. Stephenson, G. R. McBride, O. Flanagan, and G. Comer
- Subjects
medicine.medical_specialty ,Pediatrics ,medicine.diagnostic_test ,05 social sciences ,Retrospective cohort study ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,Eye examination ,Anesthesiology ,Developmental and Educational Psychology ,medicine ,Midazolam ,Autism ,0501 psychology and cognitive sciences ,General anaesthesia ,Vision test ,Adverse effect ,Psychology ,030217 neurology & neurosurgery ,050104 developmental & child psychology ,medicine.drug - Abstract
Ophthalmic examinations of developmentally delayed/autistic children are challenging. Oral midazolam may be a viable alternative to general anaesthesia for this indication. Single-centre retrospective cohort study (January 2018–March 2020). Oral midazolam (0.5 mg/kg, max 15 mg). Metrics included: patient demographics, examination completion rate, duration of stay and adverse events. 50 oral midazolam examinations were performed (45 patients). Mean age was 79.12 months. All had developmental delay (66.67% autism). Time to ophthalmic examination was 60.31 minutes. Eye examination was successfully completed in 98%. No adverse events were reported. Mean stay was 3.35 hours. Oral midazolam (0.5 mg/kg, max 15 mg) is associated with safe, successful completion of ophthalmic examinations in children previously unexaminable in clinic.
- Published
- 2020
28. Magnitude of refractive errors in children in tertiary care hospital of western Nepal
- Author
-
Srijana Thapa Godar
- Subjects
Refractive error ,Visual acuity ,medicine.diagnostic_test ,business.industry ,Visual impairment ,Astigmatism ,medicine.disease ,Subjective refraction ,medicine ,Optometry ,Vision test ,Family history ,medicine.symptom ,business ,Retinoscopy - Abstract
Background: Refractive error is one of the most common causes of the visual impairment and second leading cause of treatable blindness. The objective of the study was to determine the magnitude of refractive errors in children. Methods: This was a hospital based cross-sectional study conducted on 254 children attending Ophthalmology OPD of Manipal Teaching Hospital, Pokhara. The children whose visual acuity was worse than 6/6 but improved with pinhole were included in this study. Vision test, retinoscopy and subjective refraction was done in all subjects and cycloplegic refraction was done when needed. Statistical analysis was carried out using Epi-info version 7. Results: The commonest type of refractive error was astigmatism (46.06%) followed by myopia (42.31%). Majority of children had low grade of refractive errors (46.85%). Among the children, “with the rule astigmatism” was maximum (27.56%). Majority of children were in the age between 11 to 15 years (77.95%). The refractive error was seen more in female (63.78%). Among the children of refractive errors, 29.13% had family history, 33.46% had given the history of wearing spectacles and 10.24% children had amblyopia. There was statistically significant association between refractive errors and age groups, history of wearing spectacles, amblyopia and grading of refractive errors. However, there was no statistically significant association of refractive error with gender, residence and family history. Conclusions: Astigmatism was the common type of refractive error followed by myopia. This study emphasizes the importance of detection of refractive error in children.
- Published
- 2020
29. Augenärztliches Screening für Menschen mit geistiger und Mehrfachbehinderung
- Author
-
Bastian Grundel, Thomas Ness, Daniel Böhringer, Thomas Reinhard, Marie-Christine Bründer, Thomas Haug, and Milena Stech
- Subjects
Gynecology ,Ophthalmology ,medicine.medical_specialty ,business.industry ,medicine ,Vision test ,business - Abstract
Zusammenfassung Einführung Special Olympics Deutschland (SOD) ist die deutsche Organisation der weltweit größten Sportbewegung für Menschen mit geistiger und mehrfacher Behinderung: Viele Landesverbände von SOD bieten mittlerweile alle 4 Jahre Sommerspiele für diese Klientel an, an denen Kinder und Erwachsene aus dem jeweiligen Bundesland teilnehmen. Während der Landessommerspiele von SO Baden-Württemberg in Offenburg im Jahr 2017 konnten die Athletinnen und Athleten im Rahmen des Gesundheitsprogramms „Opening Eyes – Besser Sehen“ an einem augenärztlichen Screening teilnehmen. Methoden Optiker und Optometristen erhoben die Anamnese und Refraktion, prüften auf Farbfehlsichtigkeiten, Sehschärfe (Ferne und Nähe) sowie den orthoptischen Status. Insgesamt 4 erfahrene Ärzte in Weiterbildung und Fachärzte der Klinik für Augenheilkunde des Universitätsklinikums Freiburg führten Spaltlampenuntersuchungen, Funduskopie und Augendruckmessungen durch. Bei Bedarf wurde eine Funduskopie in Mydriase bzw. eine OCT-Untersuchung angeschlossen. Ergebnisse Insgesamt wurden 166 Personen untersucht (48% weiblich = 80; 52% männlich = 86). Der Abdecktest war in etwa 45% der Fälle in der Ferne und in 47% der Fälle in der Nähe auffällig. Sechs bzw. 11% der Patienten gaben Doppelbilder an (9/156; 17/156; jeweils Ferne und Nähe). Eine auffällige Farbsehprüfung mit weniger als 9 von 9 erkannten CVTM-Testtafeln (Color Vision Testing Made Easy nach Waggoner) wurde bei 8% (11/143) dokumentiert. Fundusauffälligkeiten sahen wir in 13% der Fälle (16/125). 41% (48/118) benötigten eine neue Brillenverschreibung. 29% (45/157) gaben eine Überempfindlichkeit gegenüber Licht an. Jeder 2. Teilnehmer hatte in den letzten 3 Jahren einen Augenarzttermin wahrgenommen; dennoch ergab die Erhebung in 10% (16/160), dass noch kein Augenarztbesuch stattgefunden hatte. In 4% der Fälle wurde eine notfallmäßige Vorstellung beim niedergelassenen Augenarzt empfohlen (z. B. im Falle eines akuten Keratokonus oder aufgrund eines erhöhten Augeninnendrucks). Eine optionale Behandlung (z. B. wegen eines Trockenen Auges) wurde in 40% der Fälle (66/166) empfohlen. Diskussion Menschen mit geistiger Behinderung beklagen allgemeine Probleme mit den Augen oder neu aufgetretene Sehprobleme nicht zwangsläufig und unmittelbar. Zusätzlich besteht möglicherweise ein eingeschränkter Zugang zur augenärztlichen Versorgung im Vergleich zu Menschen ohne geistige Behinderung. Aufgrund der 4% behandlungsbedürftiger Diagnosen sowie der 53% der Teilnehmer mit nicht optimalem Refraktionsausgleich erscheint eine augenärztliche Begleitung von Special Olympics sinnvoll, sollte verstetigt und mit öffentlichen Mitteln unterstützt werden.
- Published
- 2020
30. Changes in Choroidal Thickness Varied by Age and Refraction in Children and Adolescents: A 1-Year Longitudinal Study
- Author
-
Junjie Deng, Jianfeng Zhu, Minzhi Lv, Shuyu Xiong, Haidong Zou, Xiangui He, Jingjing Wang, Bo Zhang, and Xun Xu
- Subjects
Male ,Aging ,medicine.medical_specialty ,Longitudinal study ,Biometry ,Adolescent ,genetic structures ,Refraction, Ocular ,03 medical and health sciences ,Ocular physiology ,0302 clinical medicine ,Ophthalmology ,Myopia ,Humans ,Medicine ,Longitudinal Studies ,Prospective Studies ,Vision test ,Child ,Prospective cohort study ,030304 developmental biology ,0303 health sciences ,Choroid ,business.industry ,Vision Tests ,Organ Size ,Axial length ,Refraction ,eye diseases ,Axial Length, Eye ,medicine.anatomical_structure ,Multicenter study ,030221 ophthalmology & optometry ,Female ,sense organs ,business - Abstract
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.
- Published
- 2020
31. Surgical Outcomes of Patients with Diagnostic Preoperative Monocular Occlusion in Intermittent Exotropia
- Author
-
Ji Eun Song, So Young Han, Jin Young Lee, Chul Young Choi, and Hae Ran Chang
- Subjects
Male ,medicine.medical_specialty ,genetic structures ,lcsh:Medicine ,Diseases ,Kaplan-Meier Estimate ,Ophthalmologic Surgical Procedures ,Article ,03 medical and health sciences ,0302 clinical medicine ,Medical research ,Occlusion ,Preoperative Care ,medicine ,Prism diopters ,Humans ,Vision test ,Child ,lcsh:Science ,Survival analysis ,Fixation (histology) ,Monocular occlusion ,Multidisciplinary ,business.industry ,Vision Tests ,lcsh:R ,Health care ,Prognosis ,eye diseases ,Surgery ,Treatment Outcome ,Child, Preschool ,030221 ophthalmology & optometry ,Exotropia ,Minimum deviation ,Female ,lcsh:Q ,sense organs ,business ,Intermittent exotropia ,030217 neurology & neurosurgery - Abstract
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 (
- Published
- 2020
32. Determining and Comparing the Effective Lens Position and Refractive Outcome of a Novel Rhexis-Fixated Lens to Established Lens Designs
- Author
-
Mehdi Shajari, Theresa Niermann, Thomas Kohnen, Detlef Holland, Wolfgang J. Mayer, Ruven Sonntag, and Siegfried G. Priglinger
- Subjects
Male ,medicine.medical_specialty ,Biometry ,Pseudophakia ,genetic structures ,Anterior Chamber ,medicine.medical_treatment ,Prosthesis Design ,Refraction, Ocular ,law.invention ,03 medical and health sciences ,Ocular physiology ,0302 clinical medicine ,Lens Implantation, Intraocular ,law ,Ophthalmology ,medicine ,Humans ,Vision test ,Aged ,Retrospective Studies ,030304 developmental biology ,Aged, 80 and over ,Lenses, Intraocular ,0303 health sciences ,Phacoemulsification ,business.industry ,Vision Tests ,Middle Aged ,Cataract surgery ,Refraction ,Capsulorhexis ,eye diseases ,body regions ,Lens (optics) ,Intraocular lenses ,Capsular bag ,030221 ophthalmology & optometry ,Female ,sense organs ,business ,psychological phenomena and processes - Abstract
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.
- Published
- 2020
33. Outcomes of Bilateral Cataracts Removed in Infants 1 to 7 Months of Age Using the Toddler Aphakia and Pseudophakia Treatment Study Registry
- Author
-
Allison R. Loh, David A. Plager, Erick D. Bothun, Kimberly G. Yen, Deborah K. VanderVeen, Sharon F. Freedman, Natalie C. Weil, Scott R. Lambert, M. Edward Wilson, Elias I. Traboulsi, David G. Morrison, Rupal H. Trivedi, and Jill S. Anderson
- Subjects
Male ,medicine.medical_specialty ,Visual acuity ,Pseudophakia ,genetic structures ,medicine.medical_treatment ,Visual Acuity ,Intraocular lens ,Aphakia, Postcataract ,Cataract Extraction ,Aphakia ,Cataract ,03 medical and health sciences ,0302 clinical medicine ,Lens Implantation, Intraocular ,Ophthalmology ,medicine ,Humans ,Registries ,Vision test ,Strabismus ,Retrospective Studies ,030304 developmental biology ,0303 health sciences ,business.industry ,Vision Tests ,Infant ,Cataract surgery ,medicine.disease ,eye diseases ,Bilateral Cataracts ,Treatment Outcome ,030221 ophthalmology & optometry ,Female ,sense organs ,medicine.symptom ,business ,Follow-Up Studies - Abstract
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.
- Published
- 2020
34. Quality of life impact of refractive correction (QIRC) results three years after SMILE and FS-LASIK
- Author
-
Li Zeng, Xingtao Zhou, Jianmin Shang, Xiao Han, Ye Xu, and Tian Han
- Subjects
Adult ,Male ,medicine.medical_specialty ,Distance visual acuity ,genetic structures ,Corneal Surgery, Laser ,medicine.medical_treatment ,Keratomileusis, Laser In Situ ,Subjective ,LASIK ,lcsh:Computer applications to medicine. Medical informatics ,Glare ,03 medical and health sciences ,0302 clinical medicine ,Quality of life ,Long-term ,Refractive surgery ,Ophthalmology ,Surveys and Questionnaires ,medicine ,Myopia ,Humans ,Vision test ,Postoperative Period ,Propensity Score ,SMILE ,Retrospective Studies ,business.industry ,Research ,Significant difference ,Public Health, Environmental and Occupational Health ,Glare (vision) ,General Medicine ,Dry eye symptom ,eye diseases ,Cross-Sectional Studies ,Propensity score matching ,030221 ophthalmology & optometry ,Quality of Life ,lcsh:R858-859.7 ,Dry Eye Syndromes ,Female ,Lasers, Excimer ,sense organs ,business ,030217 neurology & neurosurgery - Abstract
Background This study aimed to compare long-term postoperative quality of life and satisfaction differences between SMILE and FS-LASIK for myopia correction. Methods This cross-sectional study enrolled patients under the age of 39 years, who chose to undergo SMILE or FS-LASIK surgery to both eyes 3 years previously. Patients completed a common vision test and Quality of Life Impact of Refractive Correction (QIRC) questionnaire, together with the surgical satisfaction, adverse symptoms subjective survey. Patients with preoperative corrected distance visual acuity and postoperative uncorrected distance visual acuity of 20/20 or greater were included. Propensity score matching (PSM) was used to match the preoperative and postoperative spherical equivalent, age, and designed optical zones of the left and right eyes between the two groups. Results Forty-nine patients were included in each group after PSM from 188 patients. No significant difference in the total QIRC score was found between the SMILE and FS-LASIK groups (45.89 ± 5.91 vs 45.09 ± 5.65, p = 0.492). There were no differences in surgical satisfaction between the groups (p = 0.178). Compared to the SMILE group, the FS-LASIK group had more glare (2.12 ± 2.25 vs 3.22 ± 2.54, p = 0.026) and severe dryness (1.80 ± 1.98 vs 2.79 ± 2.19, p = 0.021). Conclusion Postoperative quality of life is similar after SMILE or FS-LASIK. Dry eye symptoms and glare were milder in the SMILE group than in the FS-LASIK group.
- Published
- 2020
35. A Pilot Study on the Validation of Vis-Screen Mobile Application for Vision Test
- Author
-
Abdul Mutalib, Nyi Nyi Naing, Siti Nor Aishah Abdul Rahman, and Atif Amin Baig
- Subjects
business.industry ,Visually impaired ,Computer science ,Visual impairment ,Internet privacy ,Early detection ,Eye care ,Layperson ,Publishing ,medicine ,General Earth and Planetary Sciences ,Vision test ,medicine.symptom ,business ,License ,General Environmental Science - Abstract
Visual impairment and blindness is a global concern. Poor awareness and late detection are the significant factors contributing to the large number of visually impaired people worldwide. The ubiquitous use of smartphone devices will enable the public to access various eye care services provided. We are developing this application based on the need for early detection to avoid further vision loss. The simple algorithm and user-friendly features will promote any layperson to use it with minimal training. This pilot study revealed the application is highly potential to be a valid and reliable tool for vision screening in the community.Keywords: mobile application; vision screening; visual impairment; blindnesseISSN: 2514-7528 © 2020 The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.DOI: https://doi.org/10.21834/jabs.v5i15.340
- Published
- 2020
36. Is there an association between Perceptual Ability Test scores and color vision acuity?
- Author
-
Dan Tran, Spiro C. Stilianoudakis, Karoline Seekford, Courtney K. Bugas, and Terence A. Imbery
- Subjects
Male ,medicine.medical_specialty ,020205 medical informatics ,Color vision ,media_common.quotation_subject ,Color ,Color Vision Defects ,02 engineering and technology ,Audiology ,Total error ,03 medical and health sciences ,0302 clinical medicine ,Perception ,0202 electrical engineering, electronic engineering, information engineering ,Humans ,Medicine ,Vision test ,Association (psychology) ,Shade matching ,media_common ,Hue ,Color Perception Tests ,Color Vision ,business.industry ,030206 dentistry ,General Medicine ,Test (assessment) ,Female ,business ,Color Perception - Abstract
Objective The purpose of this study was to determine if there is an association between Perceptual Ability Test (PAT) results and color vision deficiency (CVD). Methods Three consecutive classes of first-year dental students (n = 291) voluntarily participated in the study. The Farnsworth-Munsell 100 Hue Color Vision test (FM-100) was administered to students beneath a Macbeth Judge II viewing booth that provided ideal lighting conditions to ascertain CVD. Results of FM-100 test were recorded as total error scores (TES). Color acuity was scored as superior (TES 0-16), average (TES 20-100), or poor (TES > 100). Additional information of age, sex, ethnicity, and time to complete the FM-100 was obtained. Multiple linear regression was used to determine the association between PAT and CVD while adjusting for age, sex, ethnicity, and time to complete the FM-100 test. Results TES ranged from 0-244. There were 132 students with superior color acuity, 161 with average, and eight with poor acuity. Females performed better than males on the FM-100 test. Time to complete the FM-100 test ranged from 3:40 minutes to 25:12 minutes. There was a strong relationship between PAT scores and CVD (P = 0.0003). A 1-unit increase in PAT scores was found to result in a 9% decrease in TES; indicating that students with higher PAT scores are less likely to have CVD. Conclusion The PAT may be a preliminary screening instrument to identify students who may have CVD. The FM-100 test can then confirm the presence of CVD. Students with CVD may desire to improve dental shade matching skills through targeted training and education.
- Published
- 2020
37. Assessment of the image quality of extended depth-of-focus intraocular lens models in polychromatic light
- Author
-
Grzegorz Łabuz, Hyeck-Soo Son, Ramin Khoramnia, Timur M. Yildirim, Gerd U. Auffarth, and Yumi Lee
- Subjects
Optics and Photonics ,Light ,Aperture ,medicine.medical_treatment ,Visual Acuity ,Intraocular lens ,Prosthesis Design ,Refraction, Ocular ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Optics ,law ,Optical transfer function ,Chromatic aberration ,Image Processing, Computer-Assisted ,medicine ,Vision test ,Lenses, Intraocular ,Physics ,Depth Perception ,business.industry ,Vision Tests ,Models, Theoretical ,Refraction ,Sensory Systems ,Lens (optics) ,Ophthalmology ,030221 ophthalmology & optometry ,Surgery ,Monochromatic color ,business ,030217 neurology & neurosurgery - Abstract
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.
- Published
- 2020
38. Study on Incidence and Progression of Refractive Errors in Medical Students
- Author
-
Babu G Ravi, P Nehakamalini, and Manjula Bussa
- Subjects
Adult ,Male ,Students, Medical ,genetic structures ,Visual Acuity ,India ,Slit Lamp Microscopy ,Ophthalmoscopy ,Urban background ,Myopia ,Prevalence ,medicine ,Humans ,Vision test ,Retrospective Studies ,High prevalence ,medicine.diagnostic_test ,business.industry ,Incidence ,Vision Tests ,Incidence (epidemiology) ,Retrospective cohort study ,General Medicine ,Refraction ,eye diseases ,Disease Progression ,Optometry ,Female ,sense organs ,High incidence ,business - Abstract
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.
- Published
- 2019
39. Comparison of the pediatric vision screening program in 18 countries across five continents
- Author
-
Patricia Arthur, Ai-Hong Chen, and Nurul Farhana Abu Bakar
- Subjects
Pediatric ,medicine.medical_specialty ,Distance visual acuity ,genetic structures ,Vision screening ,business.industry ,MEDLINE ,Scopus ,Vision tests ,Mass screening ,Article ,03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,Chart ,Family medicine ,Correspondence ,Health care ,030221 ophthalmology & optometry ,medicine ,Vision test ,business ,Limited resources ,030217 neurology & neurosurgery - Abstract
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.
- Published
- 2019
40. Design and validation of a chart-based measure of the limits of spatial contrast sensitivity
- Author
-
Beatrix Feigl, Prakash Adhikari, Andrew J. Zele, and Drew D Carter
- Subjects
Adult ,Visual acuity ,genetic structures ,Mesopic vision ,media_common.quotation_subject ,Visual Acuity ,Contrast Sensitivity ,Optics ,Chart ,medicine ,Contrast (vision) ,Humans ,Vision test ,Sensitivity (control systems) ,media_common ,Mathematics ,Color Vision ,business.industry ,Vision Tests ,Reproducibility of Results ,eye diseases ,Sensory Systems ,Ophthalmology ,Spatial frequency ,medicine.symptom ,business ,Photopic vision ,Optometry - Abstract
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.
- Published
- 2021
41. Neurodevelopment in normocephalic children with and without prenatal Zika virus exposure
- Author
-
Bianca Punch, Angelle Desiree LaBeaud, Calum N. L. Macpherson, Barbara Landon, Michelle Fernandes, Karen Blackmon, Randall Waechter, Elysse N. Grossi-Soyster, Kemi S. Burgen, Trevor Noël, Amy R. Krystosik, Nikita Cudjoe, and Roberta Evans
- Subjects
Adult ,Male ,medicine.medical_specialty ,Pediatrics ,Visual acuity ,Neurology ,West Indies ,Zika virus ,Cohort Studies ,Child Development ,Pregnancy ,medicine ,Humans ,Vision test ,Neonatology ,Prospective Studies ,Pregnancy Complications, Infectious ,biology ,business.industry ,Zika Virus Infection ,Public health ,Brain ,Infant ,Cognition ,Zika Virus ,biology.organism_classification ,Infectious Disease Transmission, Vertical ,Child, Preschool ,Prenatal Exposure Delayed Effects ,Pediatrics, Perinatology and Child Health ,Microcephaly ,Female ,medicine.symptom ,business ,Cohort study - Abstract
ObjectiveZika virus (ZIKV) targets neural stem cells in the developing brain. However, the majority of ZIKV-exposed children are born without apparent neurological manifestations. It remains unclear if these children were protected from ZIKV neurotropism or if they harbour subtle pathology that is disruptive to brain development. We assess this by comparing neurodevelopmental outcomes in normocephalic ZIKV-exposed children relative to a parallel control group of unexposed controls.DesignCohort study.SettingPublic health centres in Grenada, West Indies.Patients384 mother–child pairs were enrolled during a period of active ZIKV transmission (April 2016–March 2017) and prospectively followed up to 30 months. Child exposure status was based on laboratory assessment of prenatal and postnatal maternal serum.Main outcome measuresThe INTERGROWTH-21st Neurodevelopment Assessment (INTER-NDA) package and Cardiff Vision Tests, administered and scored by research staff masked to child’s exposure status.ResultsA total of 131 normocephalic ZIKV exposed (n=68) and unexposed (n=63) children were assessed between 22 and 30 months of age. Approximately half of these children completed vision testing. There were no group differences in sociodemographics. Deficits in visual acuity (31%) and contrast sensitivity (23%) were apparent in the ZIKV-exposed infants in the absence of cognitive, motor, language or behavioural delays.ConclusionsOverall neurodevelopment is likely to be unaffected in ZIKV-exposed children with normal head circumference at birth and normal head growth in the first 2 years of life. However, the visual system may be selectively vulnerable, which indicates the need for vision testing by 3 years of age.
- Published
- 2021
42. Visual skills essential for rugby.
- Author
-
Millard L, Breukelman GJ, Burger T, Nortje J, and Schulz J
- Abstract
Background: Keen vision is one of the most important qualities required of athletes. It enables players to perform sports-related drills and apply decision-making skills. To accurately measure the visual ability of athletes, it is important to first identify the variety of visual skills involved in the particular sport. The objectives of this novel review are to identify the most important visual skills required for rugby, and to create a reference point for further studies to include visual skills essential to rugby players., Methods: We conducted an electronic search with various combinations of relevant keywords using the following databases: Sport Discuss, Ovid's Evidence-Based Medicine Reviews, PubMed/MEDLINE, Current Contents, Science Direct, the National Research Council's Canada Institute for Scientific and Technical Information, Cochrane Database of Systematic Reviews, Google Scholar, and international electronic catalogues to assess the scientific literature related to the visual skills required for rugby. Only the records published in English were included. We extracted data on the relationship between vision and match performance, the defined problem or purpose of the study, and the inclusion of theoretical definitions of tactical behaviors., Results: Our search yielded 80 records, 51 of which fulfilled the inclusion criteria. The most important visual skills in rugby are classified based on whether they meet the requirements for visual hardware or visual software skills. Visual hardware skills include visual acuity, depth perception, fusion flexibility, and contrast sensitivity; visual software skills include eye tracking, hand-eye coordination, eye focusing, peripheral vision, speed and span of recognition, visual response time, and visual memory., Conclusions: Rugby players must use both visual hardware and software skills to reliably observe their teammates' positions, understand their opponents' actions and tactics, handle the ball, analyze the immediate circumstances, and anticipate what will occur. Further studies are needed to verify the significance of each visual skill in actual competition to determine a relationship between vision and the results of a championship., Competing Interests: None.
- Published
- 2023
- Full Text
- View/download PDF
43. Off Starburst Amacrine Cells in the Retina Trigger Looming-Evoked Fear Responses in Mice.
- Author
-
Bohl JM, Gope J, Sharpe ZJ, Shehu A, Garrett A, Koehler CC, Hellmer CB, and Ichinose T
- Subjects
- Mice, Animals, Neural Pathways, Amacrine Cells metabolism, Retina metabolism
- Abstract
A rapidly approaching dark object evokes an evolutionarily conserved fear response in both vertebrates and invertebrates, young to old. A looming visual stimulus mimics an approaching object and triggers a similarly robust fear response in mice, resulting in freeze and flight. However, the retinal neural pathway responsible for this innate response has not been fully understood. We first explored a variety of visual stimuli that reliably induced these innate responses, and found that a looming stimulus with 2-d acclimation consistently evoked fear responses. Because the fear responses were triggered by the looming stimulus with moving edges, but not by a screen flipping from light to dark, we targeted the starburst amacrine cells (SACs), crucial neurons for retinal motion detection. We used intraocular injection of diphtheria toxin (DT) in mutant mice expressing diphtheria toxin receptors (DTR) in SACs. The looming-evoked fear responses disappeared in half of the DT-injected mice, and the other mice still exhibited the fear responses. The optomotor responses (OMRs) were reduced or eliminated, which occurred independent of the disappearance of the fear responses. A histologic examination revealed that ON SACs were reduced in both mouse groups preserved or absent fear responses. In contrast, the number of OFF SACs was different among two groups. The OFF SACs were relatively preserved in mice exhibiting continued fear responses, whereas they were ablated in mice lacking fear response to looming stimulation. These results indicate that OFF SACs and the direction-selective pathway in the retina play a role in looming-induced fear behaviors., Competing Interests: The authors declare no competing financial interests., (Copyright © 2023 Bohl et al.)
- Published
- 2023
- Full Text
- View/download PDF
44. Clinical experience with Pflüger trident plates for testing color vision
- Author
-
Ishihara, Ryoko, Shimizu, Kaneo, Hamano, Kaoru, Obara, Fukuko, Ohta, Yasuo, and Drum, B., editor
- Published
- 1993
- Full Text
- View/download PDF
45. Case Study 129 Cavernous Hemangioma
- Author
-
Harrie, Roger P., Kendall, Cynthia J., Harrie, Roger P., and Kendall, Cynthia J.
- Published
- 2014
- Full Text
- View/download PDF
46. Brazilian guidelines on the frequency of ophthalmic assessment and recommended examinations in healthy children younger than 5 years
- Author
-
Luis Eduardo Morato Rebouças de Carvalho, Andrea Zin, Tomás Scalamandré Mendonça, Luisa M. Hopker, Christiane Rolim-de-Moura, Luis Carlos Ferreira de Sá, Luciana Rodrigues Silva, Marcelo Francisco Gaal Vadas, Julia D. Rossetto, Dirceu Solé, and Fábio Ejzenbaum
- Subjects
Canada ,medicine.medical_specialty ,genetic structures ,Vision screening ,Vision Disorders ,MEDLINE ,Vision tests ,Criança ,law.invention ,Randomized controlled trial ,law ,Humans ,Medicine ,Vision test ,Child ,Vision, Ocular ,Lactente ,Diagnostic techniques ,ophthalmological ,business.industry ,Infant, Newborn ,Infant ,General Medicine ,Guideline ,RE1-994 ,Técnicas de diagnóstico oftalmológico ,United States ,eye diseases ,Strabismus ,Ophthalmology ,Systematic review ,Triagem visual ,Testes visuais ,Family medicine ,Pediatric ophthalmology ,Observational study ,business ,Medical literature - Abstract
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.
- Published
- 2021
47. Environmental and Behavioral Factors with Refractive Error in Israeli Boys
- Author
-
Lisa A Ostrin, Einat Shneor, Ravid Doron, Ariela Gordon-Shaag, and Jonathan Levine
- Subjects
Male ,Refractive error ,Younger age ,Judaism ,Original Investigations ,Pilot Projects ,symbols.namesake ,medicine ,Learning to read ,Myopia ,Near work ,Humans ,Vision test ,Child ,Vision Tests ,Similar time ,medicine.disease ,Ophthalmology ,Bonferroni correction ,Sample size determination ,Jews ,symbols ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,Psychology ,Optometry ,Demography - Abstract
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.
- Published
- 2021
48. Visual and Ocular Characteristics of eSports Participants
- Author
-
Angela M. Emerson, James A. Onate, Nick Fogt, Jennifer Swingle Fogt, and William J. Kraemer
- Subjects
Refractive error ,Visual acuity ,genetic structures ,Population ,Visual Acuity ,Young Adult ,medicine ,Myopia ,Humans ,Vision test ,education ,Child ,Video game ,education.field_of_study ,business.industry ,Accommodation, Ocular ,medicine.disease ,Refractive Errors ,eye diseases ,Stereoscopic acuity ,Strabismus ,Ophthalmology ,Heterophoria ,Child, Preschool ,Optometry ,medicine.symptom ,Psychology ,business ,Accommodation - Abstract
Significance The popularity of competitive video game play is growing rapidly. Little is known about the ocular characteristics of esports participants. Refractive error and binocular measures in young adult gamers were similar to population norms. However, tear breakup time was lower, and accommodative lag was higher. Purpose In a recent report, very young video game players were found to have greater levels of refractive error and heterophoria and reduced stereopsis. The purpose of this study was to assess the visual and ocular characteristics of a group of recreational esports athletes to determine if the findings in young children were similar to findings in a group of young adult video game players. Methods Vision tests were performed on 36 college students during a video game combine event. Testing included high- and low-contrast visual acuity, autorefraction at distance and at 33 cm, stereoacuity, near heterophoria, and tear breakup time. Participants also indicated their level or rank in the game Overwatch. Results Fifteen participants were myopic, and 21 did not wear vision correction. The mean local stereopsis was 31.9 seconds. The mean of the esophoric value was 3.2 prism diopters, and the mean of the exophoric value was 5.7 prism diopters. The mean lag of accommodation was 0.81 D. The mean tear breakup time was 5.8 seconds. Average hours of play did not differ between those who wore vision correction and those who did not. There were no significant relationships between the hours of play and the ocular findings. Conclusions The prevalence of refractive error and the mean heterophoria were similar to population norms, and the mean stereoacuity was normal. However, accommodative lag was slightly higher, and the tear breakup time was lower than expected. Differences in these latter values were also noted between high- and low-level Overwatch players.
- Published
- 2021
49. The impact of spectacle lenses for myopia control on visual functions
- Author
-
Yi Gao, Bjorn Drobe, Mark A. Bullimore, Ee Woon Lim, and Adeline Yang
- Subjects
Adult ,Visual acuity ,genetic structures ,media_common.quotation_subject ,Visual Acuity ,law.invention ,Contrast Sensitivity ,law ,Foveal ,medicine ,Myopia ,Contrast (vision) ,Humans ,Vision test ,Child ,Vision, Ocular ,media_common ,eye diseases ,Sensory Systems ,Lens (optics) ,Ophthalmology ,Eyeglasses ,Useful field of view ,Fixation (visual) ,Peripheral vision ,Optometry ,medicine.symptom ,Psychology - Abstract
Purpose Spectacle lenses containing multiple small peripheral elements have been developed for myopia control in children. It is important that their effect on vision be quantified by (i) fixation through the peripheral portion, thereby using foveal vision and (ii) by fixation through the central portion and presentation of peripheral targets. Methods The above approaches were used in five studies to evaluate two novel spectacle lens designs: spectacle lenses with Highly Aspherical Lenslets (HAL) and Slightly Aspherical Lenslets (SAL). A single vision lens served as a control. Visually normal adults participated in each study. The first two studies had subjects fixate through the periphery of the lenses. High and low (10%) contrast visual acuity was measured with the Freiburg Vision Test and reading speed for high and low contrast words measured with a sentence generator. The other three studies assessed peripheral vision while subjects fixated through the central portion of the lens. Peripheral contrast sensitivity was measured using two cycles per degree drifting Gabor stimuli. Peripheral motion perception was further evaluated using random dot stimuli. Finally, attention was measured using an established test of useful field of view with three levels of complexity. Results The periphery of the HAL lens significantly reduced low contrast visual acuity, but not high contrast visual acuity, while the effect of the SAL lens was not significant for either. Neither test lens affected reading speed for high contrast words, but the HAL lens significantly affected performance for low contrast words. Neither test lens affected peripheral motion perception or useful field of view. Conclusions Low contrast visual acuity and reading was slightly reduced while high contrast visual acuity was unaffected when fixating through the periphery of the novel lens designs. None of the peripheral measures of vision was affected by the novel lens designs.
- Published
- 2021
50. An imaging-based autorefractor
- Author
-
Iain A. T. Livingstone, Mario Giardini, and Matteo Menolotto
- Subjects
business.industry ,Emmetropia ,Image processing ,Refraction ,Autorefractor ,TA164 ,Computer vision ,Meridian (astronomy) ,Sociology ,Artificial intelligence ,Vision test ,Coaxial ,business ,Projection (set theory) - Abstract
Autorefraction consists of the automatic sensing of three parameters – spherical error, cylindrical error, slope of the principal meridian – that describe the deviation of the focusing properties of an ametropic eye with respect to an emmetropic state. Low-cost autorefractors would be highly desirable in resource-poor settings, for the stratification of patients between those who can be treated in the community and those who need to be referred to specialist care. In the present paper, we describe the implementation of an autorefractor based on projecting patterns onto the retina of an eye and observing the projected pattern through an ophthalmoscopic camera configuration coaxial with the projection path. Tunable optics in the coaxial path, combined with appropriate image processing, allows determination of the three parameters. The simplicity and performance of the setup, measured on an eye simulator, shows promise towards clinical use in the community. Further work is needed to confirm the performance in vivo.
- Published
- 2021
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.