Refractive Error Research Articles

Association between vision-related quality of life and mental health status in myopia children using various optical correction aids

PurposeTo evaluate the relationship between vision-related quality of life and mental health in myopia children with various optical aids. MethodsThis cross-sectional study enrolled children aged 8–13 years, exhibiting myopia ranging from −4.50 to −0.75 D, and utilizing various optical aids for correction. Full ocular examinations and completion of two questionnaires were performed. Vision-related quality of life was evaluated using the Paediatric Refractive Error Profile (PREP), and mental health status was assessed utilising the Screen for Child Anxiety Related Emotional Disorders (SCARED). Univariate and multivariate analyses were conducted to evaluate the association between vision-related quality of life and mental health status. ResultsThe study sample comprised 209 children with corrected myopia using single vision spectacles (100 [47.8 %]), soft contact lenses (66 [31.6 %]), and orthokeratology lenses (43 [20.6 %]). The mean age was 10.31 ± 1.65 y, and males accounted for 50.7 % of the sample. The distribution of demographic characteristics showed no significant difference among all correction types, except that the myopia duration was longer for orthokeratology lens wearers than those using spectacles (P=0.03). Contact lens showed clear benefits in almost all dimensions of vision-related quality of life, especially in appearance, satisfaction, activity and peer perceptions dimensions. The prevalence of anxiety disorders among spectacle wearers was 25.0 %, the highest among all groups. For myopia children with optical corrections, not being in the top 30 percent of their class rank, reporting lower PREP scores on symptoms, handling and peer perceptions dimensions were related with a higher prevalence of anxiety disorders. ConclusionsLower vision-related quality of life was associated with worse mental health status of myopia children with optical corrections. Identifying this association is crucial for protecting the mental health of myopia children and enhancing corrective measures.

Regional disparities in the prevalence and correlated factors of myopia in children and adolescents in Gansu, China.

Myopia is a significant public health problem across the globe. This study aimed to examine the regional disparity in prevalence and correlated factors of myopia in children and adolescents in two typical regions, Gannan Tibetan Autonomous Prefecture (Gannan Prefecture for short, a Tibetan residential area) and Wuwei City (a Han residential area) in Gansu Province, China, and to provide a reference for the prevention and control of regional myopia. The study was a cross-sectional study of children and adolescents in Gansu Province, China. A total of 6,187 (Wuwei City: 3,266, Gannan Tibetan Autonomous Prefecture: 2,921) students were selected by stratified cluster sampling. Eye examinations and questionnaires were administered to the participants. Myopia is defined as a condition in which the spherical equivalent refractive error of an eye is less than or equal to -0.50 D when ocular accommodation is relaxed. The χ2 test and multivariate logistic regression analysis were used to analyze the correlated factors of myopia. The myopia rate of 6,187 students was 71.4%, and students had a higher rate of myopia (77.5%) in Wuwei City compared to Gannan Prefecture (64.6%) (p < 0.001). The results of multivariate analysis in Wuwei City showed that girls (odds ratio (OR) = 1.325), junior students (OR = 2.542), senior students(OR = 4.605), distance between eyes and book less than one foot (OR = 1.291), and parents with myopia (one, OR = 2.437; two, OR = 4.453) had higher risks of myopia (all, p < 0.05). For Gannan Prefecture, girls (OR = 1.477), senior students (OR = 1.537), daily time spent doing homework ≥2 h (OR = 1.420), the distance between eyes and book less than one foot (OR = 1.205), mean time continuous eye use (0.25-<0.5 h, OR = 1.345, 0.5-<1 h, OR = 1.317, ≥1 h, OR = 1.313), average daily sleep duration <8 h (OR = 1.399), and parents with myopia (one, OR = 1.852; two, OR = 2.913) had higher risks of myopia (all, p < 0.05). The prevalence of myopia is at a relatively high level in Gansu Province. The prevalence and risk factors for myopia vary by region.

Global estimates on the number of people blind or visually impaired by Uncorrected Refractive Error: a meta-analysis from 2000 to 2020.

Uncorrected refractive error (URE) is a readily treatable cause of visual impairment (VI). This study provides updated estimates of global and regional vision loss due to URE, presenting temporal change for VISION 2020 METHODS: Data from population-based eye disease surveys from 1980-2018 were collected. Hierarchical models estimated prevalence (95% uncertainty intervals [UI]) of blindness (presenting visual acuity (VA) < 3/60) and moderate-to-severe vision impairment (MSVI; 3/60 ≤ presenting VA < 6/18) caused by URE, stratified by age, sex, region, and year. Near VI prevalence from uncorrected presbyopia was defined as presenting near VA < N6/N8 at 40 cm when best-corrected distance (VA ≥ 6/12). In 2020, 3.7 million people (95%UI 3.10-4.29) were blind and 157 million (140-176) had MSVI due to URE, a 21.8% increase in blindness and 72.0% increase in MSVI since 2000. Age-standardised prevalence of URE blindness and MSVI decreased by 30.5% (30.7-30.3) and 2.4% (2.6-2.2) respectively during this time. In 2020, South Asia GBD super-region had the highest 50+ years age-standardised URE blindness (0.33% (0.26-0.40%)) and MSVI (10.3% (8.82-12.10%)) rates. The age-standardized ratio of women to men for URE blindness was 1.05:1.00 in 2020 and 1.03:1.00 in 2000. An estimated 419 million (295-562) people 50+ had near VI from uncorrected presbyopia, a +75.3% (74.6-76.0) increase from 2000 CONCLUSIONS: The number of cases of VI from URE substantively grew, even as age-standardised prevalence fell, since 2000, with a continued disproportionate burden by region and sex. Global population ageing will increase this burden, highlighting urgent need for novel approaches to refractive service delivery.

Evaluating a web-based visual acuity and refractive error self-assessment tool in myopic children.

Demands for myopia management are rising. A web-based tool that allows home-performed self-assessments of visual acuity (VA) and refractive error may enable hybrid care pathways and aid in identifying those with deteriorating visual performance. The tool has been validated in adult populations, but has yet to be evaluated in children. This study compared home-performed VA and refraction self-assessments to conventional measurements obtained at the clinic in a population of myopic children. Myopic children aged ≥6 years old were invited to perform web-based eye tests at home, assisted by a parent. At two myopia control clinics, they also underwent measurements of VA using a Snellen chart and refractive error using cycloplegic autorefraction. Agreement between the tests, repeatability of the web-based test and associations between clinical characteristics and web-based test accuracy were evaluated. A total of 147 children were enrolled, of whom 116 (51% male; mean age 13 ± 3 years; mean spherical equivalent refraction (SEQ) -5.58 ± 3.05) performed the web-based tests at home. Overall, the home-performed VA self-assessment and the Snellen chart assessment at the clinic agreed well (mean difference 0.03 ± 0.11 logMAR). A significant proportional bias was identified (β 0.65, p < 0.001), indicating underestimated web-based VA scores when the child's vision declined. The sensitivity to detect VA poorer than 0.10 logMAR was 94%; the specificity was 71%. The web-based refractive error algorithm measured more myopia progression compared to clinic observations (mean difference SEQ 0.40 ± 0.51 dioptres). Age, sex or use of atropine drops were not significantly associated with test accuracy. The web-based test for self-assessing vision, performed at home by children with assistance from their parents, yielded VA scores with a precision similar to Snellen chart testing conducted in a clinical setting. However, the web-based refractive error algorithm overestimated myopia progression and requires recalibration for this specific age group.

Trocar-assisted extraocular technique for intrascleral intraocular lens fixation using a 90°-curved forceps: a modified extraocular forceps-guided technique.

To investigate the surgical outcomes of intrascleral intraocular lens (IOL) fixation using a modified extraocular forceps-guided technique. Retrospective case series. Overall, 81 eyes of 78 patients who underwent intrascleral IOL fixation using the modified extraocular forceps-guided technique were included. The procedure entailed creating 2 scleral half-layer T-shaped incisions perpendicular to the main incision and forming a scleral tunnel. A 25-gauge trocar was inserted at the lower end of the T-shaped incision to perform vitrectomy. A 27-gauge needle was inserted from the left-hand port, and the leading haptic was inserted into the needle lumen. After removal of the right-hand trocar, a 90°-curved intrascleral fixation forceps was inserted into the eye, exposing the tip at the main incision, thus allowing the tip of the extraocular trailing haptic to be gripped and both haptics to be pulled out. The left-hand trocar was removed, and the haptics were buried in the scleral tunnel. The surgical outcomes of this technique were retrospectively evaluated on the basis of the medical records. The induction of haptics was successful in all cases. The preoperative best-corrected visual acuity improved from 0.35±0.68 to 0.12±0.36 logMAR postoperatively (P<0.01). The refractive error was -0.27±0.87 D; IOL decentration, 0.39±0.18 mm; IOL tilt, 5.97±2.65°; IOL astigmatism, 0.35±0.36 D; and corneal endothelial cell loss, 10.3±12.7%. There were no serious complications related to the surgical technique. The modified extraocular forceps-guided technique allows for safe and straightforward induction of the trailing haptics and enables the performance of intrascleral IOL fixation with minimal scleral incisions.

Performance of formulas included in the ESCRS intraocular lens power calculator.

We wanted to compare the refractive prediction errors (PEs) of formulas included in the ESCRS IOL power calculator to aid in informed decisions on IOL power selection based on the output of this tool. Cullen Eye Institute, Baylor College of Medicine, Houston. Retrospective case-series. We have included 748 eyes of 748 patients following implantation of one of 3 lenses, single-piece: the SN60WF (Alcon, USA), PCB00/ZCB00 (Tecnis, USA) and 3-piece: MA60MA (Alcon, USA). IOL constants recommended by the calculator were utilized for the study. We performed analysis for the whole dataset, short (<22mm) and long eyes (>25mm) as well as in subgroups based on the type of the implanted IOL. SD and RMSAE were selected as the primary endpoints. Cooke K6 had the lowest SD of PEs in the whole dataset (p<0.05) when compared with Barrett, EVO, and Hoffer-QST. In the subgroup of long eyes, the Kane formula had the lowest RMSAE (p<0.05) when compared with Barrett and EVO. We did not find any significant differences in primary endpoints for implantation of the 3 types of IOL. However, the median absolute error following implantation of the MA60MA was significantly higher than for all other formulas except for Pearl-DGS. We found significant differences in the performance of formulas included in the calculator. In the whole dataset, Cooke K6 had the lowest SD of PEs among the analyzed formulas.

Three optical intervention methods for low myopia control in children: a one-year follow-up study

ObjectiveThis study aimed to compare the one-year efficacy of myopia prevention and control using three optical intervention methods - single vision lens (SVL), highly aspherical lenslet (HAL), and orthokeratology (OK) lens - in children with low myopia.MethodsA cohort of 150 children aged 7–13 years with low myopia was recruited and divided into three groups: SVL (n = 50), HAL (n = 50), and OK lens group (n = 50), based on their preference for glasses. Follow-up assessments were carried out over one year, focusing on data from the right eye for statistical analysis. Baseline characteristics such as gender, age, axial length (AL), spherical equivalent refractive error (SER), flat keratometry (K1), steep keratometry (K2), anterior chamber depth (ACD), white-to-white corneal diameter (WTW), and non-contact tonometry (NCT) measurements were gathered and compared among the three groups before any intervention. Changes in AL growth after 1 year of intervention were assessed across the three groups. Subsequently, the AL growth control rates between the HAL and OK lens groups were compared, with the SVL group serving as the reference standard.ResultsThe study found no statistically significant variances in baseline characteristics (gender, age, SER, AL, K1, K2, WTW, and NCT) among the SVL, HAL, and OK lens groups (all p > 0.05). Following a one-year intervention, AL growth rates were as follows: HAL group (0.163 ± 0.113 mm) < OK lens group (0.280 ± 0.170 mm) < SVL group (0.516 ± 0.190 mm), with statistically significant disparities (p < 0.05). The HAL group demonstrated a higher 1-year AL growth control rate (68.41%) compared to the OK lens group (45.74%) for children aged 7–13 with low myopia, with a statistically significant differences (p < 0.001). And there was significant difference in the SER change between SVL group and HAL group (p < 0.001).ConclusionCompared to SVL, HAL and OK lens are more effective in controlling axial growth in mild myopia. Specifically, HAL maybe shows superior outcomes in both preventive and corrective measures, also it needs to be supported by more studies from randomized controlled experiments.

Vision-Specific Tools for the Assessment of Health-Related Quality of Life (HR-QoL) in Children and Adolescents with Visual Impairment: A Scoping Review.

Vision-related quality-of-life (QoL) measures offer a comprehensive evaluation of the impact of eye conditions and the effectiveness of treatment on important aspects of QoL. A substantial number of tools for assessing health-related quality of life (HR-QoL) in adults have been reviewed. However, despite the high prevalence of uncorrected refractive errors causing visual impairment (VI) in children, there is a notable lack of similar tools for this vulnerable population. This review aimed to systemically map evidence on the availability and use of vision-specific instruments for assessing HR-QoL in children and adolescents with VI. This review follows the Joanna Briggs Institute (JBI) guidelines (2020) and the framework by Arksey and O'Malley and Levac et al. (2010). We conducted systematic searches through databases PubMed, Science Direct, and Scopus and search platforms Web of Science and EBSCOhost to source reviews published in English from the date of their inception to December 2023. The findings are reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews (PRISMA-ScR). We reviewed twenty tools, nine of which were developed for children in the United States and three of which were developed for children in developing countries; no tools specifically developed for children in Africa were found. In the reviewed papers, the tools were presented to children, parents, or proxies in an interview or questionnaire format. For most of the tools, reliability was assessed using internal consistency (n = 12) and test-retest reliability (n = 12). The most dominant measures of validity were construct (n = 16), content (n = 8), internal (n = 4), and criterion (n = 4). There appears to be a need for more tools developed for children in middle-low-income countries, especially for African children.

Investigation of current guidelines for prescribing spectacles to children using a modified Delphi approach and the AGREE II tool.

This study aimed to identify clinical guidelines that provide recommendations on prescribing refractive error correction in children, evaluate the overall quality of these guidelines using the Appraisal of Guidelines for REsearch and Evaluation II (AGREE II) tool and subsequently gain consensus on the prescribing recommendations from high-quality guidelines using the modified Delphi technique. A comprehensive search for prescribing guidelines was conducted using databases and professional websites. The quality appraisal of eligible guidelines was undertaken by scoring the six AGREE II domains. Subsequently, the modified Delphi technique was used by 10 experts (sub-specialist optometrists, ophthalmologists and orthoptists) to gain consensus on the prescribing recommendation statements extracted from guidelines that had been identified as high quality. Three rounds were conducted in which agreement of these statements were scored using a 9-point Likert scale with a free-text option for any additional comments. Five eligible guidelines were identified. The AGREE II tool demonstrated that the guidelines varied substantially in quality, with only one guideline identified as being of high quality. A total of 168 prescribing statements were reviewed in the Delphi procedure. Of these, 95 statements reached expert consensus as being appropriate prescribing recommendations. There is significant scope for improving current guidelines for prescribing refractive error correction in children. We used the modified Delphi technique to find points of agreement on prescribing recommendations to support professionals prescribing refractive error correction in children. We recommend that further work is needed to address gaps in the guidelines.

High myopia: Reviews of myopia control strategies and myopia complications.

Myopia and especially high myopia are recognised as major public health concerns. Although the prevalence of high myopia in young children is low, 10-20% of high school children in Asia have high myopia, with many still progressing, and one in three patients with high myopia develop visual impairment with age. Most participants in myopia control studies have low and moderate myopia; relatively little is known about myopia control in high myopia. Literature searches were undertaken in MEDLINE and EMBASE to identify publications in English, investigating (Aim 1) the efficacy of myopia control strategies (environmental, pharmacological and optical) in high myopia (≤-6.00 D) and (Aim 2) the complications of high myopia using keywords. Outcomes included change in spherical equivalent refractive error (SE) and/or axial length (AL) to evaluate progression in high myopia. Aim 1: Twelve studies were identified that reported the efficacy of optical and pharmacological (none on environmental) interventions on AL and SE for high myopia control. A statistically significant reduction in progression of SE and AL in high myopes was reported with 1% and 0.5% atropine. Defocus Incorporated Multiple Segment spectacle lenses had lower efficacy in slowing high myopia progression compared to moderate and low myopia. Ortho-K lenses were equally effective in reducing myopia progression in low, moderate and high myopia. Aim 2: Myopic patients have an increased risk of myopic macular degeneration, retinal detachment, cataract and glaucoma, with the risk increasing with the level of myopia. High myopia has significant effects on quality of life, risk of pathological complications and vision impairment. Young children, excluding those with some syndromic associations, who are fast progressing moderate and high myopes require early intervention and close monitoring. Further research investigating the efficacy of myopia control strategies in highly myopic patients, both independently and through combination treatments, are necessary.

Reviewing the prevalence of refractive errors and color blindness among commercial drivers

Road traffic crashes pose a significant global public health concern, claiming the lives of approximately 1.19 million people each year. A worrisome trend surfaces as a considerable majority of these fatalities involve vulnerable road users, encompassing not only drivers of heavy and light vehicles but also pedestrians, cyclists, and motorcyclists. Visual impairments play a significant role in these tragic events, further exacerbating the risks faced by road users. Whether due to poor eyesight or other vision-related challenges, impaired visual perception contributes to the vulnerability of individuals on the road. This review aimed to systematically analyze the currently available research and articles to determine the prevalence of color vision defects and refractive errors among commercial drivers. The primary objective was to investigate whether refractive errors and color vision defects pose a risk factor for road safety among commercial drivers. A primary search of databases including PubMed, Google Scholar, and others was conducted using relevant keywords. Articles published between 2010 and 2023 were considered, resulting in 16 cross-sectional studies being included for analysis. Prevalence rates were calculated using weighted averages based on sample sizes. Among commercial drivers, the prevalence of color vision impairment was lower (4.35%) compared to refractive errors (23.42%). Individuals with protanopia were at higher risk of road traffic accidents (RTAs). Complex issues such as alcoholism and visual impairments contributed to higher RTA frequencies in certain populations, emphasizing the multifaceted nature of road safety challenges.

Refractive errors and the uniform patient fee scheme at a public hospital in South Africa

Background: Uniform Patient Fee Scheme (UPFS) refers to the healthcare subsidy levels provided by public hospitals in South Africa. Such subsidies indirectly reflect socio-economic factors and thus potentially might impact upon distributions of refractive error.Aim: To investigate refractive errors based on the UPFS-classified records of patients consulted at an Optometry Clinic between January 2018 and December 2019. This will provide frequencies and other measures, possibly providing preliminary estimates of prevalences for the wider population for the region concerned.Setting: The study was conducted at Sekororo Hospital in Limpopo province.Methods: Data for UPFS and refractive errors (via subjective refraction) were collected retrospectively based on the archived clinical records. Statistics and Data Analysis (Stata) software was used to analyse data.Results: For H0 in the right eyes means (± s.d.) for myopia, hyperopia, and astigmatism were −2.04 ± 2.60, 1.38 ± 1.72, and −1.07 ± 0.64, respectively. For H0 (left eyes): Myopia (−2.04 ± 2.09), hyperopia (1.47 ± 1.73), and astigmatism (−1.04 ± 0.64). For H1 (right eyes): Myopia (−1.79 ± 1.50), hyperopia (1.06 ± 0.72), and astigmatism (−1.14 ± 0.81). For H1 (left eyes): myopia (−1.71 ± 1.46), hyperopia (1.24 ± 0.91), and astigmatism (−1.71 ± 0.74). (No records were found for H2, H3, or private patients.)Conclusion: Hyperopia and astigmatism were the most common in H0 records while myopia was the most common in H1.Contribution: Various authorities and others in South Africa might use this data and results for National Health Insurance planning policies and implementation purposes.

Adopting Machine Learning to Automatically Identify a Suitable Surgery Type for Refractive Error Patients

efractive error is a visual impairment that arises when the ocular anatomy hinders the proper focusing of light onto the retina, the light-sensitive tissue layer located at the posterior region of the eye. This condition poses difficulties in achieving clear vision. Refractive error stands as the prevailing kind of visual impairment. The objective of this study is to classify two surgical approaches utilized in the treatment of refractive defects. Two commonly performed refractive surgeries are Photo-Refractive Keratectomy (PRK) and Laser-Assisted In-Situ Keratomileusis (LASIK). Artificial Intelligence (AI) encompasses a specific branch known as Machine Learning (ML), which is the focal point of this investigation. ML is dedicated to the advancement and use of algorithms that possess the capacity to acquire knowledge from data and enhance their predictive capabilities without explicit programming. The present study employs sophisticated ML methods to classify different types of refractive defect surgeries using a dataset of 124 samples obtained from Al-Rabee Hospital in Iraq, specifically focusing on corneal topography data. Two ML approaches, namely K-Nearest Neighbor (KNN) and Artificial Neural Network (ANN), are employed to predict the kind of refractive defect surgery. The findings produced from the experiment demonstrated an accuracy rate of 90.32% for the KNN algorithm and a perfect accuracy rate of 100% for the ANN algorithm. Additionally, the KNN algorithm exhibited a sensitivity of 90% and a specificity of 90.54%. The study’s findings indicate that the ANN classifier outperforms the KNN classifier.

Analysis of the Effective and Actual Lens Position by Different Formulas. Postoperative Application of a Ray-Tracing-Based Simulated Optical Model

(1) Background: This study compares the effective lens position (ELP) and intraocular lens power (IOLP) derived from SRK/T, Hoffer Q, Holladay I, and Haigis formulas with the actual lens position (ALP) and the implanted IOLP after cataract surgery. Additionally, it aims to optimize ALP using a ray-tracing-based simulated optical model to achieve emmetropia. (2) Methods: A retrospective observational study was conducted on 43 eyes implanted with the same monofocal intraocular lens (IOL). Preoperative and postoperative biometric data were collected using the Lenstar LS900. Postoperative measurements included ALP, subjective refraction, and refraction error (RE). Optical simulations (OSLO EDU 6.6.0) were utilized to optimize ALP for emmetropia (ALPIDEAL). (3) Results: Paired t-test results between REOSLO-REOBJ (p-value = 0.660) and REOSLO-RESUB (p-value = 0.789) indicated no significant statistical differences. However, statistically significant differences were found between ALP and ALPIDEAL (p &lt; 0.05), with a difference of −0.04 ± 0.45 mm [ranging from −1.00 to 1.20 mm]. A significant correlation was observed between ΔALP (ΔALP = ALP − ALPIDEAL) and RESUBJ. (4) Conclusions: This customized ray-tracing eye model effectively achieves refractive outcomes similar to those obtained both subjectively and objectively post-surgery. Additionally, it has enabled optical simulations to optimize the IOL position and achieve emmetropia.

Perception and practices of obstetricians and ophthalmologists eye diseases during pregnancy

Aims: Cesarean delivery can be crucial for both the mother and the baby, with indications often stemming from fetal or maternal health concerns. In addition to obstetric factors, non-obstetric conditions such as eye diseases frequently necessitate cesarean delivery. Among the eye diseases commonly encountered during pregnancy are refractive errors, diabetic retinopathy, ocular malignancies, and glaucoma. Some of these conditions may exacerbate during pregnancy due to related health issues like diabetes or hypertension, or they may be aggravated by the stress of vaginal labor. Consequently, the decision regarding the continuation of pregnancy, the mode of delivery, and even the choice of anesthesia can vary depending on the specific eye disease and its severity or characteristics. The aim of this study was to assess the knowledge and attitudes of obstetricians regarding the management of pregnant women with different eye conditions, with the ultimate goal of increasing awareness among obstetricians. Methods: In this study, a total of 46 obstetricians and 30 ophthalmologists practicing in Turkiye were included. Participants were surveyed to gather information, as no existing survey or scale pertaining to our study subject was available. Therefore, a novel survey form was developed based on previous studies addressing similar topics, and this survey was administered to all participants. Results: During the study, both obstetricians and ophthalmologists were queried about the management of 17 distinct eye diseases occurring during pregnancy. Ophthalmologists advocated for normal vaginal delivery (NVD) in 13 out of the 17 eye diseases. On the other hand, obstetricians opted for NVD in 5 out of the 17 cases, while recommending ophthalmology consultation in 12 out of the 17 scenarios. Conclusion: It has been noted that ophthalmologists suggest vaginal birth in 9 out of 17 eye diseases, whereas obstetricians tend to recommend consulting ophthalmologists rather than making independent decisions. This trend may stem from the fact that obstetricians may lack sufficient knowledge about eye diseases, as these conditions are not primarily within the scope of pregnancy-related care. Additionally, obstetricians might be inclined to share responsibility, possibly due to the rise in malpractice cases against obstetricians in recent years in Turkiye.

Visual Impairment, Eye Conditions, and Diagnoses of Neurodegeneration and Dementia

Vision and eye conditions are associated with increased risk for Alzheimer disease and related dementias (ADRDs), but the nature of the association and the underlying biological pathways remain unclear. If causal, vision would be an important modifiable risk factor with viable population-level interventions. To evaluate potentially causal associations between visual acuity, eye conditions (specifically cataracts and myopia), neuroimaging outcomes, and ADRDs. A cohort and 2-sample bidirectional mendelian randomization (MR) study was conducted using UK Biobank participants and summary statistics from previously published genome-wide association studies on cataract, myopia, and AD. The participants included in the analysis were aged 55 to 70 years without dementia at baseline (calendar years 2006 to 2010), underwent genotyping, and reported on eye conditions; a subset completed visual acuity examinations (n = 69 852-71 429) or brain imaging (n = 36 591-36 855). Data were analyzed from August 15, 2022, through November 28, 2023. Self-reported cataracts, visual acuity, and myopia measured by refraction error. ADRD, AD, and vascular dementia were identified from electronic medical records. Total and regional brain volumes were determined using magnetic resonance imaging. The sample included 304 953 participants (mean [SD] age, 62.1 (4.1) years; 163 825 women [53.72%]); 14 295 (4.69%) had cataracts and 2754 (3.86%) had worse than 20/40 vision. Cataracts (hazard ratio [HR], 1.18; 95% CI, 1.07-1.29) and myopia (HR, 1.35; 95% CI, 1.06-1.70) were associated with a higher hazard of ADRD. In MR analyses to estimate potential causal effects, cataracts were associated with increased risk of vascular dementia (inverse variance-weighted odds ratio [OR], 1.92; 95% CI, 1.26-2.92) but were not associated with increased dementia (OR, 1.21; 95% CI, 0.98-1.50). There were no associations between myopia and dementia. In MR for potential reverse causality, AD was not associated with cataracts (inverse variance-weighted OR, 0.99; 95% CI, 0.96-1.01). Genetic risk for cataracts was associated with smaller total brain (β = -597.43 mm3; 95% CI, -1077.87 to -117.00 mm3) and gray matter (β = -375.17 mm3; 95% CI, -680.10 to -70.24 mm3) volumes, but not other brain regions. In this cohort and MR study of UK Biobank participants, cataracts were associated with increased risk of dementia, especially vascular dementia, and reduced total brain volumes. These findings lend further support to the hypothesis that cataract extraction may reduce the risk for dementia.

A comprehensive review of binocular vision in myopia control

Myopia is a growing problem worldwide and is particularly common among young people. Myopia is a disease that affects the retina responsible for detail in the middle eye and can lead to permanent vision loss. Myopia, a prevalent refractive error causing distant objects to appear blurred, is increasingly affecting global populations, particularly children. By 2050, it's projected that half the world's population will be myopic, largely due to genetic predispositions and environmental factors like excessive near work and limited outdoor activities. A promising approach to managing myopia is binocular vision training, which involves using both eyes to create a single, clear image, potentially slowing myopia progression. Understanding the benefits of this method is critical as we move forward, especially considering the surge in myopia cases during the COVID-19 pandemic due to increased digital device use. Research underscores the importance of addressing lifestyle and promoting outdoor activities and mitigating the impact of near work can help manage myopia progression and associated binocular vision disorders. Binocular vision training shows promise for myopia control by enhancing eye coordination, potentially slowing progression. Key factors include accommodation, AC/A ratios, and phoria, which are essential for effective diagnostics and therapy. Recent research emphasizes a holistic assessment of these elements for precise management of myopia and related binocular vision disorders in children. Understanding the mechanisms and innovative approaches of binocular vision in controlling myopia, highlighting the significance of continuous research and patient education in improving eye health.

Characterising the refractive error in paediatric patients with congenital stationary night blindness: a multicentre study

Background/AaimsCongenital stationary night blindness (CSNB) is an inherited retinal disease that is often associated with high myopia and can be caused by pathological variants in multiple genes, most commonly CACNA1F,...

An Innovative Virtual Reality System for Measuring Refractive Error.

In this study, we aimed to validate a novel light field virtual reality (LFVR) system for estimating refractive errors in the human eye. Fifty participants with an average age of 22.12 ± 2.2 years (range 20-30 years) were enrolled. The present study compared spherical equivalent (SE) and focal line measurements (F1 and F2) obtained by the LFVR system with those obtained by established methods, including closed-field and open-field autorefractors, retinoscopy, and subjective refraction. The results showed substantial agreement between the LFVR system and the traditional methods, with intraclass correlation coefficients (ICC) for SE ranging from 82.7% to 86.7% (p < 0.01), and for F1 and F2 from 80.7% to 86.4% (p < 0.01). Intra-repeatability for F1 and F2 demonstrated strong agreement, with ICC values of 88.8% and 97.5%, respectively. These findings suggest that the LFVR system holds potential as a primary tool for refractive error measurement in optical care, offering high agreement and repeatability compared to conventional methods.

Long-Term Surgical Outcomes of Scleral Flap versus Scleral Pocket Technique for Sutureless Intrascleral One-Piece Lens Fixation.

Objectives: This study compared long-term surgical outcomes of the scleral flap versus scleral pocket technique for sutureless intrascleral one-piece intraocular lens (IOL) fixation. Methods: A retrospective comparative study was conducted at a single center, involving consecutive patients undergoing sutureless intrascleral one-piece IOL implantation, between January 2020 and May 2022. Eyes were divided into two groups based on the surgical technique: group 1 underwent scleral flap (n = 64), and group 2 received scleral pocket technique (n = 59). Visual acuity, refractive outcomes, and complications were assessed over a minimum 24-month follow-up period. Results: Both groups showed improvements in best-corrected visual acuity (BCVA), increasing from 0.84 ± 0.56 logMAR at baseline to 0.39 ± 0.23 logMAR (p = 0.042) at 24 months in group 1 and from 0.91 ± 0.63 logMAR at baseline to 0.45 ± 0.38 logMAR (p = 0.039) at 24 months in group 2. No significant differences in BCVA were observed between the groups at baseline (p = 0.991), 12 (p = 0.496) and 24 months (p = 0.557). Mean spherical equivalent (-0.73 ± 1.32 D in group 1 and -0.92 ± 0.99 D in group 2, p = 0.447), refractive prediction error (-0.21 ± 1.1 D in group 1 and -0.35 ± 1.8 D in group 2, p = 0.377), and surgically induced astigmatism (0.74 ± 0.89 D in group 1 and 0.85 ± 0.76 in group 2, p = 0.651) were comparable between the two groups. An IOL tilt of 5.5 ± 1.8 and 5.8 ± 2.0 degrees (p = 0.867) and an IOL decentration of 0.41 ± 0.21 mm and 0.29 ± 0.11 mm (p = 0.955) were obtained, respectively, in group 1 and group 2 at 24 months. Mean endothelial cell density remained stable at 24 months in both groups (p = 0.832 in group 1 and p = 0.443 in group 2), and it was 1747.20 ± 588.03 cells/mm2 in group 1 and 1883.71 ± 621.29 cells/mm2 in group 2 (p = 0.327) at baseline, 1545.36 ± 442.3 cells/mm2 in group 1 and 1417.44 ± 623.40 cells/mm2 in group 2 (p = 0.483) at 24 months. No cases of endophthalmitis were observed. Conclusions: The scleral pocket technique for sutureless intrascleral one-piece IOL fixation is comparable to the traditional scleral flap technique in terms of long-term visual outcomes and safety. The scleral pocket technique offers a simplified approach and a viable option even for less experienced surgeons.