Refractive Error Research Articles

Bibliometric analysis of hotspots and trends of global myopia research.

To gain insights into the global research hotspots and trends of myopia. Articles were downloaded from January 1, 2013 to December 31, 2022 from the Science Core Database website and were mainly statistically analyzed by bibliometrics software. A total of 444 institutions in 87 countries published 4124 articles. Between 2013 and 2022, China had the highest number of publications (n=1865) and the highest H-index (61). Sun Yat-sen University had the highest number of publications (n=229) and the highest H-index (33). Ophthalmology is the main category in related journals. Citations from 2020 to 2022 highlight keywords of options and reference, child health (pediatrics), myopic traction mechanism, public health, and machine learning, which represent research frontiers. Myopia has become a hot research field. China and Chinese institutions have the strongest academic influence in the field from 2013 to 2022. The main driver of myopic research is still medical or ophthalmologists. This study highlights the importance of public health in addressing the global rise in myopia, especially its impact on children's health. At present, a unified theoretical system is still needed. Accurate surgical and therapeutic solutions must be proposed for people with different characteristics to manage and intervene refractive errors. In addition, the benefits of artificial intelligence (AI) models are also reflected in disease monitoring and prediction.

Changes in ocular biometrics following cycloplegic refraction in strabismic and amblyopic children.

This study was aimed to analyze ocular biometric changes following cycloplegia in pediatric patients with strabismus and amblyopia. Cycloplegia is routinely used to measure refractive error accurately by paralyzing accommodation. However, effects on axial length (AL), anterior chamber depth (ACD), keratometry (Km), and white-to-white distance (WTW) are not well studied in this population. This retrospective study examined 797 patients (1566 eyes) undergoing cycloplegic refraction at a Samsung Kangbuk hospital pediatric ophthalmology clinic from 2010 to 2023. Ocular biometry was measured before and after instilling 1% cyclopentolate and 0.5% phenylephrine/0.5% tropicamide. Patients were categorized by strabismus diagnosis, age, refractive error and amblyopia status. Differences in AL, ACD, Km, WTW, and refractive error pre- and post-cycloplegia were analyzed using paired t tests. ACD (3.44 ± 0.33 vs 3.58 ± 0.29 mm, P < .05) and WTW (12.09 ± 0.42 vs 12.30 ± 0.60 mm, P < .05) increased significantly after cycloplegia in all groups except other strabismus subgroup (Cs) in both parameters and youngest subgroup (G1) in ACD. Refractive error demonstrated a hyperopic shift from -0.48 ± 3.00 D to -0.06 ± 3.32 D (P < .05) in overall and a myopic shift from -6.97 ± 4.27 to -8.10 ± 2.26 in high myopia (HM). Also, AL and Km did not change significantly. In conclusion, cycloplegia impacts ocular biometrics in children with strabismus and amblyopia, significantly increasing ACD and WTW. Refractive error shifts hyperopically in esotropia subgroup (ET) and myopically in high myopia subgroup (HM), eldest subgroup (G3) relating more to anterior segment changes than AL/Km. Understanding cycloplegic effects on biometry is important for optimizing refractive correction in these patients.

The knowledge structure and research trends between light and myopia: A bibliometric analysis from 1981 to 2024.

This bibliometric analysis explored the knowledge structure of and research trends in the relationship between light and myopia. Relevant literature published from 1981 to 2024 was collected from the Web of Science Core Collection database. Visual maps were generated using CiteSpace and VOSviewer. We analyzed the included studies in terms of the annual publication count, countries, institutional affiliations, prolific authors, source journals, top 10 most cited articles, keyword co-occurrence, and cocitations. A total of 525 papers examining the relationship between light and myopia published between 1981 and 2024 were collected. The United States ranked first in terms of the number of publications and actively engaged in international cooperation with other countries. The New England College of Optometry, which is located in the United States, was the most active institution and ranked first in terms of the number of publications. Schaeffel Frank was the most prolific author. The most active journal in the field was Investigative Ophthalmology & Visual Science. The most frequently cited paper in the included studies was written by Saw, SM and was published in 2002. The most common keywords in basic research included "refractive error," "longitudinal chromatic aberration," and "compensation." The most common keywords in clinical research mainly included "light exposure," "school," and "outdoor activity." The current research hotspots in this field are "progression," "refractive development," and "light exposure." The cocitation analysis generated 17 clusters. This study is the first to use bibliometric methods to analyze existing research on the relationship between light and myopia. In recent years, the intensity and wavelength of light have become research hotspots in the field. Further research on light of different intensities and wavelengths may provide new perspectives in the future for designing more effective treatments and interventions to reduce the incidence of myopia.

Prevalence of Visual Impairment in Children with Autism Spectrum Disorder: A Mini Review

The association between Visual Impairment (VI) and Autism Spectrum Disorder (ASD) remains an important research topic among children suffering from developmental delays and disabilities. The objective of this mini review was to evaluate previous literature on prevalence and etiology of visual impairment, frequency of visual impairment and types of refractive errors associated with autism in children. Previous researches on ASD found that the visual impairment is one of the major factors in autistic children. Hence measurement of vision screening in autism disorder is necessary for better explanation of the problem. The etiologies of visual impairment in autistic children were associated with refractive error and strabismus. Identification of refractive error in ASD children and providing them suitable corrective lenses may improve their visual functions and help in their daily activities. With these findings in mind, there is an urgent need to investigate further in this area and developed more detailed research. The findings would help optometrist, ophthalmologist in understanding types of visual impairment in autism school children.

Retinal Changes From Hyperopia to Myopia: Not All Diopters Are Created Equal.

To quantitatively characterize retinal changes across different quantiles of refractive error in 34,414 normal eyes of 23,064 healthy adults in the UK Biobank. Twelve optic disc (OD), foveal and vascular parameters were derived from color fundus photographs, correcting for ocular magnification as appropriate. Quantile regression was used to test the independent associations between these parameters and spherical equivalent refraction (SER) across 34 refractive quantiles (high hyperopia to high myopia)-controlling for age, sex and corneal radius. More negative SER was nonlinearly associated with greater Euclidian (largely horizontal) OD-fovea distance, larger OD, less circular OD, more obliquely orientated OD (superior pole tilted towards the fovea), brighter fovea, lower vascular complexity, less tortuous vessels, more concave (straightened out towards the fovea) papillomacular arterial/venous arcade and wider central retinal arterioles/venules. In myopia, these parameters varied more strongly with SER as myopia increased. For example, while every standard deviation (SD) decrease in vascular complexity was associated with 0.63D (right eye: 95% confidence interval [CI], 0.58-0.68) to 0.68D (left eye: 95% CI, 0.63-0.73) higher myopia in the quantile corresponding to -0.60 D, it was associated with 1.61D (right eye: 95% CI, 1.40-1.82) to 1.70D (left eye: 95% CI, 1.56-1.84) higher myopia in the most myopic quantile. OD-fovea angle (degree of vertical separation between OD and fovea) was found to vary linearly with SER, but the magnitude was of little practical importance (less than 0.10D variation per SD change in angle in almost all refractive quantiles) compared with the changes in OD-fovea distance. Several interrelated retinal changes indicative of an increasing (nonconstant) rate of mechanical stretching are evident at the posterior pole as myopia increases. These changes also suggest that the posterior pole stretches predominantly in the temporal horizontal direction.

Increasing the diagnostic yield of childhood glaucoma cases recruited into the 100,000 Genomes Project

Childhood glaucoma (CG) encompasses a heterogeneous group of genetic eye disorders that is responsible for approximately 5% of childhood blindness worldwide. Understanding the molecular aetiology is key to improving diagnosis, prognosis and unlocking the potential for optimising clinical management. In this study, we investigated 86 CG cases from 78 unrelated families of diverse ethnic backgrounds, recruited into the Genomics England 100,000 Genomes Project (GE100KGP) rare disease cohort, to improve the genetic diagnostic yield. Using the Genomics England/Genomic Medicine Centres (GE/GMC) diagnostic pipeline, 13 unrelated families were solved (13/78, 17%). Further interrogation using an expanded gene panel yielded a molecular diagnosis in 7 more unrelated families (7/78, 9%). This analysis effectively raises the total number of solved CG families in the GE100KGP to 26% (20/78 families). Twenty-five percent (5/20) of the solved families had primary congenital glaucoma (PCG), while 75% (15/20) had secondary CG; 53% of this group had non-acquired ocular anomalies (including iris hypoplasia, megalocornea, ectopia pupillae, retinal dystrophy, and refractive errors) and 47% had non-acquired systemic diseases such as cardiac abnormalities, hearing impairment, and developmental delay. CYP1B1 was the most frequently implicated gene, accounting for 55% (11/20) of the solved families. We identified two novel likely pathogenic variants in the TEK gene, in addition to one novel pathogenic copy number variant (CNV) in FOXC1. Variants that passed undetected in the GE100KGP diagnostic pipeline were likely due to limitations of the tiering process, the use of smaller gene panels during analysis, and the prioritisation of coding SNVs and indels over larger structural variants, CNVs, and non-coding variants.

Complications, Visual Acuity, and Refractive Error 3 Years after Secondary Intraocular Lens Implantation for Pediatric Aphakia

To report the cumulative incidence of complications and describe refractive error and visual acuity (VA) outcomes in children undergoing secondary intraocular lens (IOL) implantation following previous surgery for non-traumatic cataract. Pediatric cataract registry. 80 children (108 eyes: 60 bilateral, 48 unilateral) undergoing lensectomy at <13 years of age, followed by secondary IOL implantation at median age (range) of 2.7 (0.6 to 5.0) years for bilateral and 2.1 (0.5 to 6.4) for unilateral cases. Annual data collection from medical record review through 5 years following lensectomy. Cumulative incidence of newly emergent complications following secondary IOL implantation; refractive error and VA by 5 years after lensectomy. Median (interquartile range [IQR]) follow-up following secondary IOL implantation was 2.5 years (0.8 to 3.3 years). A common complication following secondary IOL implantation was a glaucoma-related adverse event (GRAE: glaucoma or glaucoma suspect); the cumulative incidence was 17% (95% CI: 3%-29%) in bilateral and 12% (95% CI: 0%-23%) in unilateral cases. The cumulative incidence of surgery for visual axis opacification was 2% (95% CI: 0%-7%) for bilateral and 4% (95% CI: 0%-10%) for unilateral cases. Median prediction error (IQR) within 90 days of implantation was 0.88 D (-0.50 D to +3.00 D) less hyperopic than intended among 21 eyes for bilateral cases and 1.50 D (-0.25 D to +2.38 D) less among 19 unilateral cases. Median (IQR) spherical equivalent refractive error at 5 years (median 5.1 years of age) in eyes receiving a secondary IOL was +0.50 D (-2.38 D to +2.94 D) for 48 bilateral and +0.06 D (-2.25 D to +0.75 D) for 22 unilateral cases. Median (IQR) monocular VA at 5 years was 20/63 (20/50-20/100) for bilateral (n=42) and 20/400 (20/160-20/800) for unilateral (n=33) cases. Eyes with secondary IOL implantation have an ongoing risk of new glaucoma-related adverse events. Five years after lensectomy (approximately 2.5 years after secondary IOL implantation), average refractive error was less hyperopic than desired given the anticipated further myopic shift before refraction stabilizes.

Prevalence of Eye Diseases of the Elderly in University Eye Clinic

Objective: To assess the prevalence of eye diseases among elderly receiving care at a University Healthcare eye service. Materials and Methods: A retrospective review of medical records was conducted for elderly patients attending Rangsit University Healthcare’s eye services between 2020 and 2021. Data collected included age, gender, underlying systemic diseases, refraction data, and results of comprehensive eye examinations. Logistic regression analysis was performed to investigate the associations between age, gender, and eye diseases. Results: Out of 22,563 patients that attended the eye service, 1,452 were aged 60 years and older. The most common eye diseases observed were uncorrected refractive errors at 71.14%, followed by cataracts including pseudophakia at 69.77%, glaucoma at 21.9%, and posterior vitreous detachment at 14.6%. Additionally, pinguecula, pterygium, and lid disorders were presented in 10.67% of cases, dry eye 8.47%, retinal breaks 6.89%, epiretinal membrane 5.85%, diabetic retinopathy 4.75%, and age-related macular degeneration 4.13%. The prevalence of retinal breaks, epiretinal membrane, diabetic retinopathy, age-related macular degeneration, glaucoma, and corneal diseases increased with age while pinguecula, pterygium, and lid disorders showed an inverse association with age. Cataracts, posterior vitreous detachment, and dry eyes were more common in women, whereas, pinguecula, pterygium, lid disorders, and corneal diseases were more prevalent in men. Refractive error, glaucoma, and age-related macular degeneration showed no gender difference. Compared to the previous national surveys in Thailand, posterior segment eye diseases were more prevalent in the present study. Conclusion: Uncorrected refractive errors, cataracts, and glaucoma were the most prevalent eye diseases observed in the elderly patients, consistent with the previous national surveys. However, the present study identified an increased prevalence of posterior segment eye diseases. Early screening and referral by optometrists for timely treatment by ophthalmologists are crucial in preventing visual loss and achieving better visual outcomes while optimizing resource utilization.

Retinopathy of prematurity in multiple births versus single births preterm, extremely preterm infants

The purpose of the study was to compare the retinopathy of prematurity in preterm, extremely preterm infants between multiple and single births.It was a hospital – based cross sectional comparative study conducted among preterm 28 - ≤37 weeks of gestational age, extremely preterm ≤ 28 weeks of gestational age at delivery of multiple and single births. Data on Gestational age, birth weight, birth order (single/multiple), Risk factors, Refractive status, and Treatment type were noted. Ophthalmological findings were performed routinely at 4 weeks and repeated later depending upon the severity. 49 infants were involved in this study; 22 were born as singletons and 27 as multiples. Our results show 2.0% of subject in stage 1, 18.4% in stage 2, 8.2% in stage 3, 2.0% in stage 4 substantially corresponds with the severity of retinopathy of prematurity due to lower gestational week and lower birth weight. Multiple birth infants statistically had 6.1% in stage 1, 18.4% in stage 2, 8.2% in stage 3, 2.0% in stage 4 retinopathy of prematurity than single birth infants. Risk factor results indicates necrotizing enterocolitis (33.3% in stage 2), oxygen (35.5% in stage 2 and 16.1% in stage 3), sepsis (37.9%, and 20.7% in stage 3), and continuous positive airway pressure (44.4% in stage 2 and 11.1% in stage 3) Compound hyperopic astigmatism was the most typical refractive error in both births. Laser treatment accounts for 18.1% in both groups. This study showed a significant correlation with ROP development in multiple births.

Cylindrical gear transmission errors influenced by temperature based on thermal network

Cylindrical gear transmission errors influenced by temperature based on thermal network

Is refractive error a factor affecting scoliosis?

Scoliosis is one of the most common surgical disorders of the pediatric spine. Refractive errors are commonly associated with vision impairment worldwide. However, it is currently unclear whether refractive error correlates directly with the development of scoliosis. A cross-sectional study was performed in 2023, and a stratified cluster sampling technique was employed among school-aged students in Nantong City, China. Univariate and multivariate logistic regression analyses were used to investigate specific correlations between scoliosis and related parameters; various types of refractive errors were also included in the study. The prevalence of scoliosis among school-aged students was 2.2% in Nantong city. Multiple logistic regression analyses showed that myopia, hyperopia, astigmatism, and anisometropia were not correlated with the development of scoliosis (all, p≥0.05). Lower body mass index (BMI) [adjusted odds ratio (aOR) = 0.92; 95% confidence interval (CI): 0.88-0.95; p<0.001], living in rural areas (aOR = 1.40; 95% CI: 1.05-1.86; p = 0.020), and older age (aOR = 1.32; 95% CI: 1.25-1.38; p<0.001) had significantly higher risks of scoliosis. Refractive errors did not correlate with the development of scoliosis. However, BMI, living in rural areas and older age did correlate with the development of scoliosis.

Systematic review and meta-analysis of the prevalence of myopia among school-age children in the Eastern Mediterranean Region.

The recent increase in myopia is a major public health concern worldwide, including in the Eastern Mediterranean Region (EMR). To provide data on the prevalence of myopia among school-age children in the EMR. This study was conducted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) protocol. We searched the Web of Sciences, Scopus, Index Medicus for the Eastern Mediterranean Region, ProQuest, PubMed, and Medline for studies on the prevalence of myopia in the EMR published from January 2000 to May 2022. The data were analysed using MedCalc version 19.6.1 and myopia was defined as refractive error ≥ 0.50 D. The overall pooled prevalence of myopia was estimated using a random-effects model and its associated 95% confidence intervals. The meta-analysis included 27 quality-assessed studies from 13 countries among 51 111 school-age children. The overall pooled prevalence of childhood myopia from 2000 to 2022 was 5.23%, which was significantly higher among females than males (4.90% vs 3.94%). The prevalence of myopia was significantly higher among children aged 11-17 years than among those aged 5-10 years (7.50% vs 3.90%). There was a higher prevalence of myopia with cycloplegic refraction than noncycloplegic refraction (5.95% vs 3.73%). There was highly significant heterogeneity between the studies. Prevalence of myopia among school-age children in the EMR was high, particularly among older children, and it was more common among females. Early intervention to slow myopia progression is essential in the EMR to protect children from irreversible vision loss.

Exploring the Relationship Between Maternal Nutrition During Pregnancy and Childhood Amblyopia and Myopia Risk: Longitudinal Cohort Studies

This study aimed to investigate the relationship between pregnancy and myopia onset or progression in young adult women, utilizing a longitudinal cohort design with a substantial sample size. Myopia is a prevalent refractive error with significant public health and economic implications. There are genetic and environmental risk factors for myopia; however, the role of pregnancy in the development of myopia is unknown. No longitudinal studies with extensive sample sizes have clarified the relationship between pregnancy and myopia. This study included 100 women aged 20–50 years, who were followed up biennially for up to 14 years. Pregnancy occurrences and myopia assessments were recorded. A comparison of individuals with and without pregnancies revealed differences in the incidence of myopia and amblyopia, their ages, and body mass index. Hazard ratios for myopia onset or progression were significantly lower in individuals with at least one pregnancy, particularly during the early follow-up periods. Sensitivity analyses and adjustments for confounders supported these findings. This study demonstrated that pregnancy may prevent myopia onset or progression, particularly during early adulthood. Future research should confirm these findings and investigate the underlying mechanisms, informing clinical decisions, including refractive surgery timing in women of childbearing age.

The Performance of Spot Photoscreener in 6 to 10 Weeks Infants in China: A Cross-Sectional Study.

To compare the refractive errors measured by the Spot photoscreener (with or without cycloplegia) to cycloplegic retinoscopy in 6- to 10-week-old infants. 101 right eyes from 101 healthy infants aged 6 to 10 weeks were recruited for this cross-sectional observational study. Refractive errors were measured using Spot photoscreener before and after cycloplegia, as well as cycloplegic retinoscopy. Comparisons between the refractive measurements were performed using one-way ANOVA with the post hoc Tukey HSD test or Kruskal-Wallis test with the Steel-Dwass test according to the data normality. Pearson's correlation test and 95% confidence intervals were calculated. The agreement was evaluated using a Bland-Altman plot with 95% limits of agreement of the differences. Spot photoscreener was found to underestimate the spherical equivalent by 2.33 Diopters (D) in these infants. Following the induction of cycloplegia, the spherical equivalent measured by Spot photoscreener was in excellent agreement with cycloplegic retinoscopy with the mean difference of 0.01 D. Spot photoscreener overestimated cylindrical parameter by 0.2 D with poor agreement with cycloplegic retinoscopy no matter whether cycloplegia was induced. It had good agreement with cycloplegic retinoscopy in the J0 vector than the J45 vector measurement. With the induction of cycloplegia, Spot photoscreener can accurately evaluate spherical equivalent in hyperopic infants with mild-to-moderate astigmatism. While it may provide valuable measurements of astigmatism, discrepancies in cylinder and axis should be taken into account.

Refractive error accuracy and user perceptions of a smartphone home-based tester

Background: Uncorrected refractive error accounts for nearly half of the global burden of vision impairment. The EyeQue personal vision tracker (EPVT) was created as a convenient smartphone refractometer to be used at home and order spectacles online thereafter. However, its accuracy in diagnosing refractive error has not been fully established.Aim: This study aimed to determine the accuracy of the EPVT in measurement of refractive error and determine user perception on device use.Setting: University of KwaZulu-Natal optometry clinic, Westville campus.Methods: This was a comparative cross-sectional study using a double-blind design. Objective, non-cycloplegic refraction testing results using the EPVT were compared with gold standard ophthalmic subjective refraction (SR). Both eyes were considered for the analysis with comparisons being made between EPVT and gold subjective standard refraction for each eye. User perception was evaluated by means of a structured questionnaire.Results: The mean spherical equivalent refractive error was –0.18 ± 0.70 dioptre (D) and –1.12 ± 2.79 D for the gold standard ophthalmic SR and EPVT, respectively, with significant differences in visual acuities yielded by the two methods (p = 0.000). Participants preferred gold standard refraction testing over the EPVT.Conclusion: The EPVT was not accurate in measuring refractive error; therefore, the resultant prescription from EPVT alone should not be used to order spectacles. However, this digital tool presents promise as an autorefractor for screening refractive error rather than as a diagnostic device.Contribution: This study offered valuable insights into the prospective utility of home-based, self-administered smartphone refractive error testers as a tool for screening of refractive error. The study also provided cautions to the EPVTs limitations related to accuracy and limited ocular health assessment, which have broader implications for visual health and quality.

Creation of a Corneal Flap for Laser In Situ Keratomileusis Using a Three-Dimensional Femtosecond Laser Cut: Clinical and Optical Coherence Tomography Features

Laser in situ keratomileusis (LASIK) is the most frequently used technique for the surgical correction of refractive errors on the cornea. It entails the creation of a superficial hinged corneal flap using a femtosecond laser, ablation of the underlying stromal bed using an excimer laser, and repositioning of the flap. A corneal flap with an angled side cut reduces the risk of flap dislocation and infiltration of epithelial cells and confers unique biomechanical properties to the cornea. A new laser software creating three-dimensional (3D) flaps using a custom angle side cut was retrospectively evaluated, comparing optical coherence tomography 3D (with intended 90° side cut) and 2D flaps (with tapered side cuts) as well as respective intra- and early postoperative complications. Four hundred consecutive eyes were included, two hundred for each group. In the 3D group, the mean edge angle was 92°, and the procedure was on average 5.2 s slower (p = 0). Non-visually significant flap folds were found in thirteen eyes of the 2D group and in seven eyes of the 3D group (p = 0.17). In conclusion, the creation of a LASIK flap using a 3D femtosecond laser cut, although slightly slower, was safe and effective. The side cut angle was predictable and accurate.

Myopia Is an Ischemic Eye Condition: A Review from the Perspective of Choroidal Blood Flow.

Myopia is a common refractive error that affects a large proportion of the population. Recent studies have revealed that alterations in choroidal thickness (ChT) and choroidal blood flow (ChBF) play important roles in the progression of myopia. Reduced ChBF could affect scleral cellular matrix remodeling, which leads to axial elongation and further myopia progression. As ChT and ChBF could be used as potential biomarkers for the progression of myopia, several recent myopia treatments have targeted alterations in ChT and ChBF. Our review provides a comprehensive overview of the recent literature review on the relationship between ChBF and myopia. We also highlight the importance of ChT and ChBF in the progression of myopia and the potential of ChT as an important biomarker for myopia progression. This summary has significant implications for the development of novel strategies for preventing and treating myopia.

Ocular disorders in a tertiary Hospital in South East Nigeria

The object of this study was to determine the pattern of ocular disease patients that presented to the Enugu State University of Science and Technology Teaching Hospital, Park Lane, Enugu, Nigeria. A retrospective study was conducted, where the medical case notes of patients who had ocular examinations, other clinical examinations, and investigations from April 2022 through December 2022 were retrieved. There were a total of 1145 patients, with a male population of 476 (41.6%), while females were 669 (58.4%). The mean age of the study population was 40.8 years, with a Standard Deviation (SD) of 22.4. A total of 924 (80.7%) participants were adults while children (aged 16 years and below) were 221 in number and constituted 19.3% of the study population. The most common eye disease was refractive error, which occurred in 266 (23.2%) of the participants; it was followed by allergic eye diseases, 201 (17.6%), cataract, 170 (14.9%), glaucoma, 111 (9.7%), and trauma to the eye, 94 (8.2%). Among the children, the most common eye disease seen were allergic eye diseases, 78 (35.3%), followed by refractive error, 70 (31.7%), trauma, 21 (9.5%), cataract, 11 (5.0%), while infections of the eye were 10 (4.5%). The most common eye disease among the adult participants was refractive error, 196 (21.1%), and then cataract, 159 (17.2%), allergic eye diseases, 123 (13.3%), glaucoma, 105 (11.4%), and retinal pathologies, 82 (8.9%). The most common causes of eye diseases in this study were refractive error, allergic eye diseases, cataracts, glaucoma, and trauma. Health education at community and primary health care level could help to reduce the number of people with avoidable causes of visual impairment.

Enhancing the structure–function relationship in glaucoma using anatomical compensation of retinal nerve fibre layer

Background/aimsTo investigate whether compensating retinal nerve fibre layer (RNFL) thickness measurements for demographic and anatomical ocular factors can strengthen the structure–function relationship in patients with glaucoma.Methods600 eyes from 412 patients...

Dependence of Body Stability on Optical Conditions during VR Viewing

The dependence of body stability on the distance between the optical centers of VR-device lenses and the refractive error status of users during VR viewing was investigated. Participants included 31 adults, and their postural-control ability was measured using a BTrackS device. The optical conditions were (1) COCD (comfortable optical center distance), (2) COCD+2D (comfortable optical center distance with 2D myopia), (3) COCD-2D (comfortable optical center distance with 2D hyperopia), (4) DOCD (uncomfortable optical center distance), (5) DOCD+2D (uncomfortable optical center distance with 2D myopia), and (6) DOCD-2D (uncomfortable optical center distance with 2D hyperopia). Posture was assessed under these six optical conditions while the participants were wearing a VR device and watching a 3D roller-coaster video. The sway-path length was significantly increased under the COCD-2D, DOCD, DOCD+2D, and DOCD-2D conditions compared to the COCD condition (p &lt; 0.05). In the case of maximum sway velocity, the results showed significant increases under the DOCD, DOCD+2D, and DOCD-2D conditions compared to the COCD condition (p &lt; 0.05). The analysis revealed that when users are viewing VR displays, optimization of the distance to the optical center of the VR-device lenses and correction of the refractive errors for individual users was a significant factor in minimizing body instability.