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Clinical & Experimental Optometry May 2020The role of visual acuity and refractive errors in the academic performance of children is controversial due to the variable quality of the research in this area and the... (Review)
Review
The role of visual acuity and refractive errors in the academic performance of children is controversial due to the variable quality of the research in this area and the mixed findings reported. This review aims to provide clarity by reviewing and critiquing relevant peer-reviewed publications and also summarises what is known regarding the visual demands of modern classroom environments. The outcomes of this review suggest that while a number of studies have investigated the role of vision in relation to children's academic performances, the veracity of the evidence obtained from the majority of these studies is undermined by methodological limitations. Comparisons between studies are constrained by differences in experimental designs, instrumentation and sample characteristics. Despite these limitations, the weight of evidence suggests there is an association between academic performance and both visual acuity and refractive error in children. However, well-designed experimental studies are necessary to further understand the relationship between these parameters.
Topics: Academic Performance; Child; Humans; Refractive Errors; Vision, Binocular; Visual Acuity
PubMed: 31441091
DOI: 10.1111/cxo.12953 -
Journal of Optometry 2023To determine the fixation disparity and refractive error of first-year optometry students to ascertain any relationship between them and also identify any association...
PURPOSE
To determine the fixation disparity and refractive error of first-year optometry students to ascertain any relationship between them and also identify any association between fixation disparity and visual symptoms at near.
METHOD
It was an analytical cross-sectional study involving 85 participants aged 17 to 27 years (18.60 ± 1.37), 41% of whom were males. Subjective refraction was done at 3 m and fixation disparity was measured with and without spectacle correction using the Wesson Fixation Disparity Card. All analysis was set within a 95% confidence interval with a p-value ≤ 0.05 considered statistically significant.
RESULTS
Refractive error ranged from 0.25 SEQ (spherical equivalent) to 5.50 SEQ. Mean fixation disparity ranged from 2.9 ± 2.6 to 3.9 ± 2.8 min arc. There was no statistically significant correlation between refractive error and fixation disparity without correction (r = -0.180, p = 0.098) and with correction (r = 0.155, p = 0.157). For fixation disparity in the ortho and exo direction, mean fixation disparity with correction of participants who experienced headaches during or after reading (5.1 ± 2.6 min arc) was significantly higher (p = 0.032) than participants who did not (2.0 ± 2.6 min arc).
CONCLUSION
Myopia is common among first-year optometry students. Refractive error has no significant effect on fixation disparity. Headache is significantly associated with exo fixation disparity at near.
Topics: Male; Humans; Female; Optometry; Vision Disparity; Cross-Sectional Studies; Refractive Errors; Refraction, Ocular; Students
PubMed: 35690554
DOI: 10.1016/j.optom.2022.04.001 -
Indian Journal of Ophthalmology Jun 2022To determine the pattern of refractive error among commercial drivers in north India.
PURPOSE
To determine the pattern of refractive error among commercial drivers in north India.
METHODS
Descriptive study with convenient sampling conducted among commercial drivers of north India.
RESULTS
A total of 213 (75.8%) heavy-vehicle and 68 (24.2%) light-vehicle drivers were screened for eye diseases. Refractive error for distance was reported in 44 (15.7%; 95% CI: 11.6-20.4) drivers. Hyperopia was reported in 23 (8.2%; 95% CI: 5.2-12) drivers, followed by myopia in 15 (5.3%; 95% CI: 3-8.6) drivers and astigmatism in six (2.1%; 95% CI: 0.7-4.5) drivers. Presbyopia was reported in 157 (55.8%) drivers. Dry eye was reported in 70 (24.9%), stereo deficiency in 77 (27.4%), and color vision deficiency in 11 (3.9%) drivers. Three drivers were diagnosed with cataract, and two were referred for retina evaluation.
CONCLUSION
Hyperopia in both eyes was the most common refractive error. Dry eye disease and color vision deficiency were also reported. Most of the drivers were not using spectacles for refractive error correction. Due to their mobile nature, drivers with cataract and retina diseases did not turn up for follow-up.
Topics: Cataract; Color Vision Defects; Humans; Hyperopia; Prevalence; Refractive Errors
PubMed: 35647994
DOI: 10.4103/ijo.IJO_2510_21 -
Ethiopian Journal of Health Sciences Jul 2022The objective of this study was to determine the causes and distribution of vision impairment and refractive error among children in Zimbabwe.
BACKGROUND
The objective of this study was to determine the causes and distribution of vision impairment and refractive error among children in Zimbabwe.
METHODS
A hospital-based retrospective cross-sectional study was conducted among children (3-16) who attended the Eye Institute, Harare, Zimbabwe, from January 2010 to December 2020. Patients' records were collated, and variables such as visual acuity, ocular morbidities, and vision impairment were analysed.
RESULTS
During this time, 1038 children with mean age of 10.63 ± 3.54 years visited the facility. The majority of them were males (53.2%). Prior to treatment, 9.9% of the children had vision impairment which reduced to 3.5% after intervention. Uncorrected refractive error accounted for the majority of vision impairment (67.0%), followed by keratoconus (7.8%), corneal opacity/ulceration (6.8%), and amblyopia (6.8%), among other conditions. Astigmatism (60.6%) was the most prevalent type of refractive error followed by myopia (37.5%).
CONCLUSION
The prevalence of childhood vision impairment is higher than that found in similar hospital-based studies conducted in Africa. The most common reason for childhood vision impairment was uncorrected refractive error.
Topics: Adolescent; Child; Cross-Sectional Studies; Female; Hospitals; Humans; Male; Prevalence; Refractive Errors; Retrospective Studies; Vision Disorders; Zimbabwe
PubMed: 35950070
DOI: 10.4314/ejhs.v32i4.8 -
Contact Lens & Anterior Eye : the... Apr 2022To investigate the relationship between axial length (AL) and refractive error (RE).
PURPOSE
To investigate the relationship between axial length (AL) and refractive error (RE).
METHODS
Participants comprised Chinese university students. In total, 894 eyes with low hyperopia to emmetropia (-0.50D ≤ spherical equivalent (SE) ≤ +2.00D), and 1007 eyes with moderate to high myopia (-11.00D ≤ SE ≤ -4.00D) were analyzed. Cycloplegic RE and AL were measured with an autorefractor and IOL Master respectively. The association between AL and RE was evaluated by linear regression. Furthermore, differences in the mean AL, as well as the correlation between AL and ocular refraction, were evaluated according to SE, sex, and age.
RESULTS
In both the moderate to high myopia and low hyperopia to emmetropia groups, mean AL was significantly longer in men (26.48 mm, confidence interval (CI) 26.41-26.56 mm; 23.82 mm, CI: 23.76-23.88 mm, respectively) than in women (25.78 mm, CI: 25.71-25.86 mm; 23.25 mm, CI: 23.17-23.33 mm, respectively). For both men and women, mean AL significantly differed among four SE groups (+0.50D < SE ≤ +2.00D, -0.50D ≤ SE ≤ +0.50D, -4.00D ≤ SE ≤ -6.00D, SE < -6.00D, P < 0.001). The correlation coefficient between AL and ocular refraction was -0.318 and -0.277 in male and female participants, respectively, with low hyperopia to emmetropia (-0.50D ≤ SE ≤ +2.00D), and -0.545 and -0.437 in male and female participants, respectively, with moderate to high myopia (-11.00D ≤ SE ≤ -4.00D). There were no age-related effects on SE (P = 0.714) or AL (P = 0.952).
CONCLUSIONS
Ocular refraction is negatively correlated with AL in Chinese university students. The correlation coefficient is greater in those with moderate to high myopia than in those with low hyperopia to emmetropia. Furthermore, the AL is longer in men than in women.
Topics: Axial Length, Eye; China; Female; Humans; Hyperopia; Male; Myopia; Refraction, Ocular; Refractive Errors; Students; Universities
PubMed: 34030907
DOI: 10.1016/j.clae.2021.101470 -
BMJ Open Ophthalmology Oct 2023Myopia is the refractive error that shows the highest prevalence for younger ages in Southeast Asia and its projection over the next decades indicates that this...
OBJECTIVE
Myopia is the refractive error that shows the highest prevalence for younger ages in Southeast Asia and its projection over the next decades indicates that this situation will worsen. Nowadays, several management solutions are being applied to help fight its onset and development, nonetheless, the applications of these techniques depend on a clear and reliable assessment of risk to develop myopia.
METHODS AND ANALYSIS
In this study, population-based data of Chinese children were used to develop a machine learning-based algorithm that enables the risk assessment of myopia's onset and development. Cross-sectional data of 12 780 kids together with longitudinal data of 226 kids containing age, gender, biometry and refractive parameters were used for the development of the models.
RESULTS
A combination of support vector regression and Gaussian process regression resulted in the best performing algorithm. The Pearson correlation coefficient between prediction and measured data was 0.77, whereas the bias was -0.05 D and the limits of agreement was 0.85 D (95% CI: -0.91 to 0.80D).
DISCUSSION
The developed algorithm uses accessible inputs to provide an estimate of refractive development and may serve as guide for the eye care professional to help determine the individual best strategy for management of myopia.
Topics: Child; Humans; Cross-Sectional Studies; Refractive Errors; Myopia; Refraction, Ocular; Machine Learning
PubMed: 37793703
DOI: 10.1136/bmjophth-2023-001298 -
Investigative Ophthalmology & Visual... Feb 2021Refractive errors, particularly myopia, are common and a leading cause of blindness. This study aimed to explore associations between medications and refractive error in...
PURPOSE
Refractive errors, particularly myopia, are common and a leading cause of blindness. This study aimed to explore associations between medications and refractive error in an aging adult cohort and to determine whether childhood-onset refractive errors predict future medication use to provide novel insights into disease mechanisms.
METHODS
The study compared the spherical equivalent values measured in 102,318 UK Biobank participants taking the 960 most commonly used medications. The strengths of associations were evaluated against the self-reported age of spectacle wear. The causality of refractive error changes was inferred using sensitivity and Mendelian randomization analyses.
RESULTS
Anti-glaucoma drugs were associated with 1 to 2 diopters greater myopic refraction, particularly in subjects who started wearing correction in the first two decades of life, potentially due to the association of higher intraocular pressure since early years with both myopia and, later in life, glaucoma. All classes of pain-control medications, including paracetamol, opiates, non-steroidal antiinflammatory drugs, and gabapentinoids, were associated with greater hyperopia (+0.68-1.15 diopters), after correction for deprivation, education, and polypharmacy and sensitivity analyses for common diagnoses. Oral hypoglycemics (metformin, gliburonide) were associated with myopia, as was allopurinol, and participants using bronchodilators (ipratropium and salbutamol) were more hyperopic.
CONCLUSIONS
This study finds for the first time, to our knowledge, that medication use is associated with refractive error in adults. The novel finding that analgesics are associated with hyperopic refraction, and the possibility that multisite chronic pain predisposes to hyperopia, deserves further research. Some drugs, such as antihyperglycemic or bronchodilators, may directly alter refractive error. Intraocular pressure appears causative for myopia.
Topics: Aging; Blindness; Female; Glaucoma; Humans; Incidence; Intraocular Pressure; Male; Middle Aged; Population Surveillance; Refraction, Ocular; Refractive Errors; Risk Factors; United Kingdom
PubMed: 33591358
DOI: 10.1167/iovs.62.2.15 -
Nigerian Journal of Clinical Practice Mar 2022To determine the prevalence and pattern of uncorrected refractive error among staff of a Nigerian university.
AIMS AND BACKGROUND
To determine the prevalence and pattern of uncorrected refractive error among staff of a Nigerian university.
PATIENT AND METHODS
A cross-sectional study of consecutive staff of the University of Nigeria, Nsukka, Nigeria who presented for a 10-day free eye screening program. Demographic data and data on eye care awareness and knowledge were obtained with a combination of self-administered and interviewer-administered questionnaires in the English language. Clinical examinations included visual acuity taken at 6 m with Snellen's chart; noncontact tonometry; pen-torch eye examination; and direct ophthalmoscopy; autorefraction and subjective refraction.
RESULTS
One thousand and eighty-three subjects aged 18-82 years (mean = 44.1 ± 12.15 years) comprising 568 females (52.4%) and 515 males (47.6%) were screened. Eighty-nine subjects (8.3%) were visually impaired and five subjects (0.5%) were blind. Three hundred and fifty-six subjects were diagnosed with refractive error (356/1083; 32.9%), out of which 149 subjects (41.9%) were uncorrected. The prevalence of uncorrected refractive error in this study population was 13.8%. Astigmatism was the commonest refractive error, whereas hypermetropia and hypermetropic astigmatism were the commonest spherical and astigmatic errors, respectively.
CONCLUSION
A significant proportion of the staff of this Nigerian university still lives with uncorrected refractive error with its attendant consequences. Regular eye checks should be done by the staff of our universities and effort should be intensified in eye care awareness creation among the populace, including the apparently enlightened communities.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Refractive Errors; Universities; Vision Tests; Visual Acuity; Young Adult
PubMed: 35295061
DOI: 10.4103/njcp.njcp_1603_21 -
Investigative Ophthalmology & Visual... Mar 2022Refractive errors are common eye disorders characterized by a mismatch between the focal power of the eye and its axial length. An increased axial length is a common... (Review)
Review
Refractive errors are common eye disorders characterized by a mismatch between the focal power of the eye and its axial length. An increased axial length is a common cause of the refractive error myopia (nearsightedness). The substantial increase in myopia prevalence over the last decades has raised public health concerns because myopia can lead to severe ocular complications later in life. Genomewide association studies (GWAS) have made considerable contributions to the understanding of the genetic architecture of refractive errors. Among the hundreds of genetic variants identified, common variants near the gap junction delta-2 (GJD2) gene have consistently been reported as one of the top hits. GJD2 encodes the connexin 36 (Cx36) protein, which forms gap junction channels and is highly expressed in the neural retina. In this review, we provide current evidence that links GJD2(Cx36) to the development of myopia. We summarize the gap junctional communication in the eye and the specific role of GJD2(Cx36) in retinal processing of visual signals. Finally, we discuss the pathways involving dopamine and gap junction phosphorylation and coupling as potential mechanisms that may explain the role of GJD2(Cx36) in refractive error development.
Topics: Connexins; Gap Junctions; Humans; Myopia; Refractive Errors; Retina; Gap Junction delta-2 Protein
PubMed: 35262731
DOI: 10.1167/iovs.63.3.5 -
Optometry and Vision Science : Official... Jan 2021This study presents the relationship between distance visual acuity and a range of uncorrected refractive errors, a complex association that is fundamental to clinical...
SIGNIFICANCE
This study presents the relationship between distance visual acuity and a range of uncorrected refractive errors, a complex association that is fundamental to clinical eye care and the identification of children needing refractive correction.
PURPOSE
This study aimed to analyze data from the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study to describe the relationship between distance uncorrected refractive error and visual acuity in children.
METHODS
Subjects were 2212 children (51.2% female) 6 to 14 years of age (mean ± standard deviation, 10.2 ± 2.1 years) participating in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error Study between 2000 and 2010. Uncorrected distance visual acuity was measured using a high-contrast projected logMAR chart. Cycloplegic refractive error was measured using the Grand Seiko WR-5100K autorefractor. The ability of logMAR acuity to detect various categories of refractive error was examined using receiver operating characteristic curves.
RESULTS
Isoacuity curves show that increasing myopic spherical refractive errors, increasing astigmatic refractive errors, or a combination of both reduces distance visual acuity. Visual acuity was reduced by approximately 0.5 minutes of MAR per 0.30 to 0.40 D of spherical refractive error and by approximately 0.5 minutes of MAR per 0.60 to 0.90 D of astigmatism. Higher uncorrected hyperopic refractive error had little effect on distance visual acuity. Receiver operating characteristic curve analysis suggests that a logMAR distance acuity of 0.20 to 0.32 provides the best balance between sensitivity and specificity for detecting refractive errors other than hyperopia. Distance acuity alone was ineffective for detecting hyperopic refractive errors.
CONCLUSIONS
Higher myopic and/or astigmatic refractive errors were associated with predictable reductions in uncorrected distance visual acuity. The reduction in acuity per diopter of cylindrical error was about half that for spherical myopic error. Although distance acuity may be a useful adjunct to the detection of myopic spherocylindrical refractive errors, accommodation presumably prevents acuity from assisting in the detection of hyperopia. Alternate procedures need to be used to detect hyperopia.
Topics: Accommodation, Ocular; Adolescent; Astigmatism; Child; Distance Perception; Female; Humans; Hyperopia; Male; Myopia; ROC Curve; Refractive Errors; Sensitivity and Specificity; Vision Tests; Visual Acuity
PubMed: 33394925
DOI: 10.1097/OPX.0000000000001630