Spherical Equivalent Refraction Research Articles

Two-Year Results of 0.01% Atropine Eye Drops and 0.1% Loading Dose for Myopia Progression Reduction in Danish Children: A Placebo-Controlled, Randomized Clinical Trial.

We investigated the two-year safety and efficacy of 0.1% loading dose and 0.01% low-dose atropine eye drops in Danish children for reduction in myopia progression in an investigator-initiated, placebo-controlled, double-masked, randomized clinical trial. Ninety-seven six- to twelve-year old myopic participants were randomized to 0.1% loading dose for six months and then 0.01% for eighteen months (loading dose group, N = 33), 0.01% for two years (0.01% group, N = 32) or placebo for two years (placebo, N = 32). Axial length (AL) and spherical equivalent refraction (SER) were primary outcomes. Secondary outcomes included adverse events and reactions, choroidal thickness, and other ocular biometrical measures. Outcomes were measured from baseline and at six-month intervals. Individual eyes nested by participant ID were analyzed with linear-mixed model analysis. Data were analyzed with intention-to-treat. Mean AL was 0.08 mm less (95% confidence interval (CI): -0.01; 0.17, p-value = 0.08) in the 0.1% loading dose and 0.10 mm less (95% CI: 0.01; 0.19, p-value = 0.02) in the 0.01% group after two years of treatment compared to placebo. Mean SER progression was 0.12 D (95% CI: -0.10; 0.33) less in the loading dose and 0.26 D (95% CI: 0.04; 0.48) less in the 0.01% groups after two years of treatment compared to placebo (p-value = 0.30 and 0.02, respectively). In total, 17 adverse events were reported in the second-year follow-up, and all were rated as mild. Adjusting for iris color did not affect treatment effect estimates. Intra-ocular pressure increased over two years comparably between all groups but remained within normal limits. Two-year treatment with 0.01% low-dose atropine eye drops is a safe and moderately efficacious intervention in Danish children for reducing myopia progression.

Paediatric norms for photopic electroretinogram testing based on a large cohort of Chinese preschool children

ObjectiveFull-field electroretinogram (ffERG) is an objective test to determine the electroretinal activities in response to light stimulation for investigating retinal physiology and diagnosing retinal diseases. This study aimed to establish...

Effects of virtual distant viewing technology on preventing nearwork-induced ocular parameter changes.

This study investigates whether virtual distant viewing technology can prevent nearwork-induced ocular parameter changes. Twenty-six volunteers read a textbook on one day and the same content on a virtual distant viewing display on another day based on a randomization sequence, with both reading sessions at 33 cm for 4 hours. Visual acuity, diopter, ocular biology, visual fatigue, and accommodative function before and after the nearwork, as well as the number of pages read, were recorded. After 4 hours of nearwork in the textbook group, the spherical equivalent refraction decreased from -3.13 ± 2.65 D to -3.32 ± 2.70 D (P < 0.001), corneal thickness decreased from 531.6 ± 33.5 μm to 528.9 ± 33.0 μm (P = 0.015), anterior chamber depth decreased from 3.65 ± 0.35 mm to 3.60 ± 0.30 mm (P = 0.002), accommodative facility increased from 15.1 ± 3.5 to 16.4 ± 3.9 (P = 0.018), and subjective visual fatigue increased from 14.0 ± 9.2 to 19.3 ± 7.6 (P = 0.002); no significant changes were seen in the other parameters. In the virtual distant viewing group, the spherical equivalent refraction (from -3.17 ± 2.60 D to -3.11 ± 2.73 D, P = 0.427), corneal thickness (from 531.9 ± 32.8 μm to 529.7 ± 33.2 μm, P = 0.054), and anterior chamber depth (from 3.67 ± 0.35 mm to 3.69 ± 0.32 mm, P = 0.331) did not show significant changes, whereas accommodative facility increased from 14.7 ± 5.8 to 15.9 ± 5.5 (P = 0.042) and subjective visual fatigue increased from 13.5 ± 8.4 to 18.9 ± 8.6 (P = 0.002). In addition, choroidal thickness (from 217.7 ± 76.0 μm to 243.0 ± 85.0 μm, P = 0.043), positive relative accommodation (from -2.32 ± 1.07 D to -2.85 ± 0.89 D, P = 0.007), and amplitude of accommodation (from 7.26 ± 1.41 D to 7.89 ± 1.69 D, P = 0.022) also significantly increased in the virtual distant viewing group. The textbook group and the virtual distant viewing group read 176.0 ± 133.1 pages and 188.0 ± 102.0 pages, respectively, and there was no significant difference between the two groups (P = 0.708). Virtual distant viewing technology can prevent the increase in myopia degree due to nearwork and improve accommodation function without increasing visual fatigue.

Development of a risk score for myopia: A cohort study conducted among school-aged children in China.

To evaluate the myopia risk in school-aged children one year after lifting a pandemic-related lockdown and develop a tool to identify high-risk groups. In total, 38,079 children without myopia from 38 schools were included. The outcomes were myopia incidence and progression in 1 year after the COVID-19 lockdown was lifted, both obtained by the spherical equivalent refraction (SER). We separated the population into an exploratory (75%) and a validation sample (25%) to construct the risk score model. In total, 9811 (29.57%) students became myopic, and the overall myopia progression was 0.22 ± 0.62 D. Even less myopia progression was noted in the pre-myopia group at baseline (All: P = 0.045, Boy: P = 0.005). The risk score model included seven predictors: gender, grade, SER at baseline, residence, parental myopia, eye discomfort symptoms, and online courses. The model had a score range of 0-46 and an optimal cutoff of 34. The area under the receiver operating curve of the model was 0.726 (0.719-0.732) for the exploratory sample and 0.731 (0.720-0.742) for the validation sample. The risk score can serve as a practical tool for classifying the risk of myopia in school-aged children.

Correction Method for Optical Scaling of Fundoscopy Images: Development, Validation, and First Implementation.

Although fundus photography is extensively used in ophthalmology, refraction prevents accurate distance measurement on fundus images, as the resulting scaling differs between subjects due to varying ocular anatomy. We propose a PARaxial Optical fundus Scaling (PAROS) method to correct for this variation using commonly available clinical data. The complete optics of the eye and fundus camera were modeled using ray transfer matrix formalism to obtain fundus image magnification. The subject's ocular geometry was personalized using biometry, spherical equivalent of refraction (RSE), keratometry, and/or corneal topography data. The PAROS method was validated using 41 different eye phantoms and subsequently evaluated in 44 healthy phakic subjects (of whom 11 had phakic intraocular lenses [pIOLs]), 29 pseudophakic subjects, and 21 patients with uveal melanoma. Validation of the PAROS method showed small differences between model and actual image magnification (maximum 3.3%). Relative to the average eye, large differences in fundus magnification were observed, ranging from 0.79 to 1.48. Magnification was strongly inversely related to RSE (R2=0.67). In phakic subjects, magnification was directly proportional to axial length (R2=0.34). The inverse relation was seen in pIOL (R2=0.79) and pseudophakic (R2=0.12) subjects. RSE was a strong contributor to magnification differences (1%-83%). As this effect is not considered in the commonly used Bennett-Littmann method, statistically significant differences up to 40% (mean absolute 9%) were observed compared to the PAROS method (P<0.001). The significant differences in fundus image scaling observed among subjects can be accurately accounted for with the PAROS method, enabling more accurate quantitative assessment of fundus photography.

Binocular balance across spatial frequency in anisomyopia.

Anisomyopia is prevalent in myopia and studies have reported it exhibits impaired binocular function. We investigated the binocular balance across spatial frequency in adults with anisomyopia and compared it to in individuals with less differences in refractive error, and examined whether ocular characteristics can predict binocular balance in anisomyopia. Fifteen anisomyopes, 15 isomyopes and 12 emmetropes were recruited. Binocular balance was quantitatively measured at 0.5, 1, 2 and 4 c/d. The first two groups of the observers were tested with and without optical correction with contact lenses. Emmetropes were tested without optical correction. Binocular balance across spatial frequency in optically corrected anisomyopes and isomyopes, as well as emmetropes were found to be similar. Their binocular balance nevertheless still got worse as a function of spatial frequency. However, before optical correction, anisomyopes but not isomyopes showed significant imbalance at higher spatial frequencies. There was a significant correlation between the dependence on spatial frequency of binocular imbalance in uncorrected anisomyopia and interocular difference in visual acuity, and between the dependence and interocular difference in spherical equivalent refraction. Anisomyopes had intact binocular balance following correction across spatial frequency compared to those in isomyopes and emmetropes. Their balance was weakly correlated with their refractive status after optical correction. However, their binocular balance before correction and binocular improvement following optical correction were strongly correlated with differences in ocular characteristics between eyes.

Relationship between biometry, fovea, and choroidal thickness in Nigerian children with myopia

Background: Understanding the relationship between biometric and structural changes in childhood myopia is necessary to effectively manage myopia progression.Aim: To determine the relationship between ocular biometry, fovea and sub-fovea choroidal thickness in school-aged children with myopia of Nigerian descent.Setting: Abuja, Nigeria.Methods: This study involved 189 children (117 girls and 72 boys), and myopia was defined as cycloplegic spherical equivalent refraction (SER) of ≤ −0.50 D. Keratometry values, biometry data, fovea and sub-foveal choroidal thickness (SFChT) values were obtained from medical records retrospectively and analysed.Results: The median age was 13 years (interquartile range [IQR]: 5). The median SER, fovea and SFChTs were −2.63 D (IQR: 3.38), 249 μm (IQR: 118) and 225 μm (IQR: 341), respectively. Male children had flatter corneas, thicker fovea and thinner SFChT compared to female children. The vitreous chamber and axial length were longer and sub-fovea choroid was thinner in children with high myopia. There was a weak but significant positive correlation between myopia and sub-fovea choroidal thickness (r = 0.270 respectively, P 0.01). A moderate negative correlation was found between myopia and vitreous chamber depth (r = −0.536, P 0.001), and a strong negative correlation was found between myopia and axial length (r = −0.706, P 0.001).Conclusion: Myopia in school-aged Nigerian children is associated with sub-fovea choroidal thinning, increased vitreous chamber depth and axial elongation.Contribution: This study provides data on the relationship between ocular biometry, fovea and sub-foveal choroidal thickness in school-aged Nigerian children with myopia.

Lifestyle Factors in Myopic Spanish Children.

Childhood myopia represents a global concern with increasing prevalence in recent decades. Lifestyle factors significantly impact myopia. To evaluate lifestyle factors in myopic children from a metropolitan area in Europe. This was a descriptive study including myopic subjects aged 4-18 years. Patient demographic and clinical data were collected, including cycloplegic refraction in spherical equivalent refraction (SER) and axial length (AL). In addition, a questionnaire on lifestyle factors was conducted between September 2022 and April 2023. A total of 321 myopic children were included, aged 10.72 ± 3.05 years, of whom 51.4% were boys, with SER -2.25 ± 1.9 D and AL 24.54 ± 0.98 mm. The mean age of myopia onset was 7.69 ± 3.05 years. A total of 59.8% had family history of myopia. Those children who had <2 h/day of screen time (on weekdays) presented SER -2 ± 1.91 D, compared to those who had >2 h/day, SER: -2.50 ±1.88 D (p = 0.009). Children who spent <2 h/day doing near work after school were less myopic compared to those who spent >2 h/day (SER: -1.75 ± 1.83 vs. SER: -2.75 ± 1.82, respectively, p = 0.03). However, no significant association was observed between SER and AL and time spent outdoors nor between SER and AL and academic performance (p > 0.05). Screen time and near-work time appear to be lifestyle factors related to myopia.

The impact of accommodation function on the difference between noncycloplegic and cycloplegic refraction in adult myopes.

To investigate the impact of accommodation function on the difference between cycloplegic and noncycloplegic subjective and automatic refraction in adult myopes. Myopic patients between 18 and 50 years old evaluated at Peking University Third Hospital who underwent cycloplegic and noncycloplegic automatic and subjective refraction were enrolled. Accommodation function, including negative and positive relative accommodation (PRA/NRA) and accommodation response (binocular cross cylinder, BCC) was examined. Of the 3268 individuals enrolled, the mean age was 27.3 ± 6.9 years, and 34.8% of participants were male. The noncycloplegic spherical equivalent (SE) was 0.23 ± 0.29 D and 0.64 ± 0.61 D more myopic than cycloplegic subjective and automatic refraction. Adjusting for associated factors, participants with at least 0.50 D of more myopia SE refraction by noncycloplegic subjective refraction were more likely to be older (odds ratio [OR], 1.029; 95% confidence interval [CI], 1.013-1.045) and with insufficient (OR, 1.514; 95% CI, 1.093-2.096) and excessive (OR, 2.196; 95% CI, 1.538-3.137) NRA value. The automatic refraction SE difference of at least 1.00 D more myopia was more likely to be found in individuals with older age (OR, 1.036; 95% CI, 1.022-1.050) and accommodative lead (OR, 1.255; 95% CI, 1.004-1.568). A quarter of adult myopes had at least 0.50 and 1.00 D of subjective and automatic SE difference with cycloplegia. The accommodation function significantly affects the difference between cycloplegic and noncycloplegic refraction. Investigating the differences in refraction measurement guarantees the proper use of cycloplegia in adults for myopia correction.

Accommodation and Binocular Vision in Children with Myopic Anisometropia.

To assess the differences in accommodation and binocular vision in children with myopic anisometropia and determine the correlation with anisometropia. A total of 110 patients with myopia aged 8-15 years were recruited from June 2021 to February 2022 from the Affiliated Hospital of Xuzhou Medical University. Based on the interocular differences of spherical equivalent refraction, patients were divided into the isometropia (35 children), low anisometropia (LA group, 42 children), and high anisometropia (HA group, 33 children). The variables assessed were refraction, heterophoria, amplitude of accommodation (AMP), accommodative response (AR), gradient AC/A, positive and negative relative accommodation (PRA/NRA), and near stereopsis in the three groups. Pearson's correlation coefficient tests were used to investigate the possible association between each parameter and interocular differences (IODs). Among 110 subjects, there were 49 males and 61 females with a mean age of 11.39 ± 2.28 years. Compared with those in the isometropia group, AMP was lower and near stereopsis was higher in the LA group, and the distance and near heterophoria, PRA, AR, and near stereopsis were higher, and PRA, AMP, and gradient AC/A were lower in the HA group (all P < 0.05). Compared with those in the LA group, the near stereopsis, AR, and the near stereopsis were higher in the HA group, and the gradient AC/A was lower (all P < 0.05). However, no significant differences existed in the negative relative accommodation (P > 0.05). The distance and near heterophoria, AR, AMP, and near stereopsis were observed to be correlated with IODs, respectively (r = -0.259, p = 0.006; r = -0.201, p = 0.036; r = 0.306, p = 0.001; r = -0.315, p = 0.001; r = 0.535, p < 0.001). Our results suggested that with the increase of anisometropia, distance and near heterophoria, AR, AMP, and near stereopsis had a tendency to get worse in children with myopic anisometropia.

The Effect of Myopic Control between the Dual-Focus Contact Lenses and High-Concentration Atropine in an Asian Population.

We aim to investigate the myopic control effect of high-concentration atropine (ATR) and dual-focus contact lenses (DFCLs). A retrospective cohort study was conducted. A total of 182 eyes in 91 individuals who used high-concentration ATR (0.125%) and another 70 eyes in 35 individuals who used DFCLs were enrolled in the ATR and DFCL groups, respectively. The primary outcomes were spherical equivalent refraction (SER) progression and axial length (AXL) elongation. The generalized estimate equation was utilized to yield the adjusted odds ratio (aOR) and 95% confidence interval (CI) of cycloplegic SER progression and AXL elongation between groups. According to the multivariable analysis, the change in cycloplegic SER progression was similar between the DFCL and ATR groups (aOR: 1.305, 95% CI: 0.247-2.515, p = 0.803). The DFCL group demonstrated a numerically higher rate of AXL elongation compared to the ATR group (aOR: 1.530, 95% CI: 0.980-1.894, p = 0.051). In the subgroup analysis, cycloplegic SER progression was insignificant between ATR and DFCL users in different subgroups (all p > 0.05). The DFCL patients with moderate astigmatism and high AXL (both p < 0.001) presented a high risk of AXL elongation. In conclusion, DFCL usage demonstrated similar myopic control of cycloplegic SER and AXL compared to high-concentration ATR, while DFCLs showed lower AXL control, mainly in patients with moderate astigmatism and high AXL.

Comparison of Visual Field Fluctuation Between Myopic and Emmetropic Glaucoma Patients

Background: Conflicting epidemiologic studies suggest that myopia may both increase and decrease the risk of glaucomatous visual field loss. To provide appropriate treatment to glaucoma patients, it is important to detect meaningful changes in the visual field, which requires distinguishing between visual field fluctuation and progression. Visual field fluctuation is defined as the variability between two visual field tests performed on separate days or months on the same eye that cannot be attributed to a pathologic change. We hypothesize that glaucoma patients with myopia will demonstrate more visual field fluctuation compared to emmetropic patients.&#x0D; Methods: Four or more 24-2 or 30-2 Humphrey visual field tests over several visits will be analyzed per patient. Data including the VFI plot, mean deviation, and threshold sensitivity on the glaucoma progression analysis will be collected to measure fluctuation. The sample is divided into two groups: 1. emmetropic glaucoma patients with a spherical equivalent refraction between +2 to -2 diopters and 2. high myopic glaucoma patients with a spherical equivalent refraction over -5 diopters. Bland-Altman plots, Mann-Whitney U tests, Root Mean Square Error (RMSE), intraclass correlation coefficients, and generalized estimating equation models for ordinal data will be used to analyze the collected data.&#x0D; Results: Thus far, 2,979 charts have been reviewed with data collected from 27 emmetropes and myopes who met the inclusion criteria. The recruitment goal is 78 per group and 156 total. Preliminary results for RMSE found a statistically significant p-value for mean deviation (0.0320), and no statistically significant difference for threshold sensitivity (0.5179) and VFI (0.0904).&#x0D; Conclusion and Potential Impact: This ongoing study will help establish if glaucoma patients with high myopia demonstrate greater visual field fluctuation. It is important for clinicians to have this information so that these patients can be examined carefully to prevent misdiagnoses or delayed glaucoma treatment.

The long and short of it: a comprehensive assessment of axial length estimation in myopic eyes from ocular and demographic variables.

Axial length, a key measurement in myopia management, is not accessible in many settings. We aimed to develop and assess machine learning models to estimate the axial length of young myopic eyes. Linear regression, symbolic regression, gradient boosting and multilayer perceptron models were developed using age, sex, cycloplegic spherical equivalent refraction (SER) and corneal curvature. Training data were from 8135 (28% myopic) children and adolescents from Ireland, Northern Ireland and China. Model performance was tested on an additional 300 myopic individuals using traditional metrics alongside the estimated axial length vs age relationship. Linear regression and receiver operator characteristics (ROC) curves were used for statistical analysis. The contribution of the effective crystalline lens power to error in axial length estimation was calculated to define the latter's physiological limits. Axial length estimation models were applicable across all testing regions (p ≥ 0.96 for training by testing region interaction). The linear regression model performed best based on agreement metrics (mean absolute error [MAE] = 0.31 mm, coefficient of repeatability = 0.79 mm) and a smooth, monotonic estimated axial length vs age relationship. This model was better at identifying high-risk eyes (axial length >98th centile) than SER alone (area under the curve 0.89 vs 0.79, respectively). Without knowing lens power, the calculated limits of axial length estimation were 0.30 mm for MAE and 0.75 mm for coefficient of repeatability. In myopic eyes, we demonstrated superior axial length estimation with a linear regression model utilising age, sex and refractive metrics and showed its clinical utility as a risk stratification tool.

Lens power, cornea power and association with refractive error in children with moderate to high hyperopia.

This study aimed to profile ocular biometry parameters and predictors of spherical equivalent refraction (SER) among children with moderate to high hyperopia. Individuals <18 years of age with moderate to high hyperopia were enrolled from November 2015 to November 2021. Participants underwent a series of comprehensive ocular examinations, and were classified as having low hyperopia, that is, SER +0.5 to < +2.0 D or moderate to high hyperopia, that is, SER ≥ +2.0 D. A total of 459 and 230 eyes with moderate to high hyperopia and low hyperopia, respectively, were included. Moderate to high hyperopic eyes had a shorter axial length, stronger lens power (24.78 ± 5.47 D vs. 18.74 ± 1.63 D, p < 0.001) and weaker corneal power (42.82 ± 1.75 D vs. 43.31 ± 1.55 D, p < 0.001) than low hyperopic eyes. When comparing values before and after 5 years of age, both lens power and axial length differed significantly in the moderate to high hyperopia group, whereas in the low hyperopia group, they only differed significantly after 9 years of age. Lens power was negatively associated with AL in eyes with axial lengths between 20 and 22 mm. A multiple linear regression model which included axial length (standardised β = -0.80, p < 0.001), corneal power (standardised β = -0.47, p < 0.001) and lens power (standardised β = 0.23, p < 0.001) explained 81.2% of the variance in SER. Differences in lens power and axial length in moderate to high hyperopic eyes became significantly smaller after 5 years of age, at least 4 years earlier than for the low hyperopia. Lens power could offset the axial elongation in participants with axial lengths between 20 and 22 mm, suggesting that children with moderate to high hyperopia might have different ocular growth patterns. Axial length, corneal power and lens power were the main predictors of SER in moderate to high hyperopia.

Choroidal thickness as a biomarker for axial length change

Aims/Purpose: Assessing axial eye growth is a key component in myopia management; however, access to biometry is limited in primary eye care settings. This study evaluated choroidal thickness, compared to spherical equivalent refraction, as a potential biomarker of axial elongation.Methods: The Myopia Outcome Study of Atropine in Children (MOSAIC) is a double‐blind, randomized controlled trial of 0.01% atropine eye drops. Irish myopic participants aged 6–16 years used either 0.01% atropine or placebo eye drops nightly for 2 years. Spherical equivalent refraction (SER) was measured by cycloplegic autorefraction, axial length (AL) by partial coherence interferometry and choroidal thickness (ChT) by Swept Source‐OCT. The respective 12‐month changes in both eyes were included in mixed linear regression analysis, while controlling for treatment group and within‐subject correlation. ROC analysis was conducted to assess the ability of ChT and/or SER to identify eyes in the top 25% (fast progressors) of AL change.Results: Of the 250 participants enrolled in MOSAIC (mean age 11.8 years, 62% female), 217 (87%) completed the 12‐month visit. Mean 12‐month change in AL, ChT and SER were 0.268 ± 0.19 mm, −3.62 ± 33.3 um and −0.437 ± 0.346 DS respectively. Analysis revealed a significant association between change in ChT and AL (−0.01 ± 0.002 mm per 10 μm; p &lt; 0.001) and change in SER and AL (−0.28 ± 0.02 mm per 1D; p &lt; 0.001). When both SER and ChT were combined in a single model, a 1D myopic change in SER and a 10um decrease in ChT were associated with a 0.27 mm (p &lt; 0.001) and 0.007 mm increase in AL (p = 0.002), respectively. ROC analysis revealed that change in ChT was a stronger predictor of fast AL progression (AUC = 0.77) compared to SER change (AUC = 0.72), with the combined model performing better than either variable alone (AUC = 0.80).Conclusions: ChT change was significantly associated with AL change over 12 months and better than SER alone at identifying fast AL progressors, with a combined SER and ChT model achieving the best results.

Epidemiological characteristics of myopia among school-age children before, during, and after the COVID-19 pandemic: a cohort study in Shenzhen, China.

To evaluate the epidemiological characteristics of myopia among school-aged children before, during, and after the coronavirus disease (COVID-19) pandemic. A total of 848,697 students aged 6-15 years from 786 primary and secondary schools in Shenzhen, China, were randomly selected as research subjects. We conducted annual myopia screenings from 2019 to 2022. 2019 was considered before the COVID-19 pandemic, 2020 as during the pandemic, and 2021 and 2022 as after the pandemic. Demographic characteristics, visual acuity, and spherical equivalent refraction (SE) were collected. During the 4-year follow-up period, the uncorrected visual acuity (UCVA) of the study subjects progressed following a trend of -0.18 ± 0.30D (-0.17 ± 0.29D for boys, -0.21 ± 0.32Dfor girls) (p < 0.001). Those students who were in grade 4 aged 9-10 years at the baseline examination showed the greatest decline in visual acuity (0.23). The SE of the study subjects progressed following a trend of -1.00 ± 1.27D (-0.96 ± 1.25D for boys, -1.05 ± 1.31D for girls) (p < 0.001). The students who were in grade 5 aged 10-11 years at the baseline examination showed the greatest decline in SE (1.15D ± 1.22, p < 0.001). The prevalence of myopia (UCVA<5.0 and SE < -0.50D of any eye) increased by 28.2% (27.0% for boys and 29.8% for girls). Those students who were in grade 2 aged 7-8 years at the baseline examination showed the greatest increase in myopia prevalence (37.6%, p < 0.001). During the COVID-19 pandemic, the subjects' visual acuity and SE measurements decreased by -0.05 ± 0.19 (p < 0.001) and - 0.36 ± 0.89D (p < 0.001) respectively, and the prevalence of myopia increased by 11.3% (10.6% for boys and 12.2% for girls) (p < 0.001). The 3-year cumulative incidence of myopia for non-myopic grade 1 aged 6-7 years students with baseline SE of ≥1.00D, ≥ 0.50D and < 1.00D, ≥0D and < 0.50D, and ≥ -0.50D and < 0D were 6.8, 24.8, 39.0, and 48.1%, respectively. During the COVID-19 pandemic, the SE of school-aged children showed myopic drift and decreased visual acuity. Myopia progressed faster among girls than among boys in the same grades. The risk of myopia among school-aged children persisted even after the home quarantine of the COVID-19 pandemic was lifted.

Characteristics of Peripheral Retinal Refraction and Its Role in Children with Different Refractive States.

Peripheral retinal refraction plays a crucial role in myopia, but the specific mechanism is not clear. We refined the retinal partitions to explore the characteristics of peripheral retinal refraction and its role in emmetropic, low, and moderate myopic children aged 6 to 12 years. A total of 814 subjects (814 eyes) were enrolled in the study. The participants were divided into three groups according to the central spherical equivalent refraction (SER), which were emmetropia group (E), low myopia group (LM) and moderate myopia group (MM). Multispectral refractive topography (MRT) was used to measure the retinal absolute and relative refractive difference value (RDV) in different regions. The range was divided into superior, inferior, temporal, and nasal RDV (SRDV, IRDV, TRDV, and NRDV) on the basis of several concentric circles extending outward from the macular fovea (RDV15, RDV30, RDV45, RDV30-15, RDV45-30, and RDV-45). Kruskal-Wallis test was used to analyze the differences of peripheral refraction for all the regions among the three groups. Spearman rank correlation was performed to explore correlations between SER and RDV, axial length (AL) and RDV. The absolute value of RDV decreased with increasing degree of myopia in all regions (P < 0.01). Subjects with different refractive degrees had different relative value of RDV. In nasal position within 45° and temporal position within 30°, the peripheral retina exhibited significantly different relative hyperopic refractive status among Group E, Group LM, and Group MM (P < 0.05). SER was negatively correlated with NRDV within 30° (especially in the range of NRDV30-15) (r = -0.141, P < 0.01), positively correlated with TRDV within 15° (r = 0.080, P = 0.023), and not significantly correlated with SRDV and IRDV when the retina was divided into four parts. AL was positively correlated with NRDV within 30° (especially in the range of NRDV30-15) (r = 0.109, P = 0.002), negatively correlated with TRDV within 15° (r = -0.095, P = 0.007). The peripheral defocus has significant implications for the genesis of myopia. The peripheral defocus of the horizontal direction, especially within the range of NRDV30, has greater effect on the development of myopia in children. Higher NRDV30 is associated with lower SER and longer AL.

Efficacy of repeated low-level red-light therapy combined with optical lenses for myopia control in children and adolescents.

To evaluate the efficacy of repeated low-level red-light (RLRL) therapy combined with optical lenses in children and adolescents with myopia. This retrospective study included 108 children and adolescents. Based on the difference in the combination intervention scheme participants were divided into four groups based on the intervention they received: the RLRL+orthokeratology (OK) lens intervention group (RLRL+OK group), the RLRL+defocus distributed multi-point (DDM) lens intervention group (RLRL+DDM group), the RLRL+single-vision spectacles (SVS) intervention group (RLRL+SVS group), and a control group. Visual acuity, spherical equivalent refraction (SER), and axial length (AL) were measured before and after the intervention. Binary logistic regression was used to identify factors influencing vision recovery. The SER and AL at baseline were statistically different (P<0.01). After the intervention, the AL increase in the RLRL+OK, RLRL+DDM, and RLRL+SVS groups was significantly better than the control group across time points (P<0.001). Changes in SER were also statistically significant in the RLRL+DDM and RLRL+SVS groups compared to the control group across time points (P<0.001). The intervention method was identified as a significant factor influencing vision recovery (P<0.001). RLRL therapy combined with optical lenses is effective in controlling myopia progression in children and adolescents.

Comparison of myopic control between orthokeratology contact lenses and defocus incorporated multiple segments spectacle lenses.

Purpose: The purpose of this study was to compare the differences in myopic control effects between orthokeratology (OK) contact lenses and defocus incorporated multiple segments (DIMS) spectacle lenses. Methods: A retrospective cohort study was conducted that included patients who had received OK lens, DIMS spectacle lens or single-vision spectacle treatments. A total of 54 eyes from 27 individuals, 38 eyes from 19 individuals and 42 eyes from 21 individuals were enrolled into the OK lens, DIMS and control groups, respectively. The primary outcomes were the changes in the spherical equivalent refraction (SER) and axial length (AXL) among the groups. A repeated-measure ANCOVA was adopted to calculate the SER progression and AXL elongation of the OK lens group compared with the DIMS group. Results: The difference in the SER progression was clinically non-significant in the OK lens group compared with the DIMS and control groups (P = 0.001). The total AXL elongation results were similar between the OK lens and DIMS groups, but these were lower than in the control group (P = 0.005). The repeated-measure ANCOVA revealed that the SER progression difference during the study interval was clinically non-significant in the OK lens group when compared with the DIMS group (P = 0.028). The AXL elongation results between the OK lens and DIMS populations did not illustrate a significant difference (P = 0.607). In a subgroup analysis of moderate astigmatism, better AXL control was observed in the DIMS subgroup compared with the OK lens subgroup (P = 0.016). Conclusions: The OK lens demonstrated a clinically non-significant effect on the SER and AXL controls compared with the DIMS spectacle lens.

Refractive outcomes following silicone oil tamponade in vitreoretinal surgery.

To evaluate the factors influencing the refractive outcomes following silicone oil tamponade (SOT) and silicone oil removal (SOR) in different lens statuses post-vitreoretinal surgery. Retrospective analysis of three different lens statuses. This was a descriptive study that included 150 eyes of 147 patients who had undergone pars plana vitrectomy with SOT and SOR between January 2017 and June 2021. Demographic profile, spherical equivalent refraction (SER), and its association with clinical features were evaluated with SOT and post-SOR. The mean (±standard deviation [SD]) age was 47 ± 17.8 years, including all three groups. SER was represented in diopters (D). The mean ± SD refraction with SOT in phakic, pseudophakic, and aphakic was 4.28 ± 2.59 D, 2.94 ± 2.58 D, and 3.98 ± 4.82 D. The mean SER post-SOR in phakic, pseudophakic, and aphakic was -2.72 ± 2.03 D, -1.12 ± 1.41 D, and 8.22 ± 3.70 D. The diagnosis of rhegmatogenous retinal detachment (RRD) among 96 eyes (64%) is the common indicator to perform vitreoretinal (VR) surgery. A minority of subjects were managed with retinal lasers before VR surgery (14%). The macula was attached in 100 eyes (67.6%), the belt buckle was done in 37 eyes (24.7%), and the silicone oil viscosity with 1000 centistoke was chosen in 129 eyes (86%). SOT was used as a tamponade in VR surgeries irrespective of lens status. The significant predictor for post-SOR refraction in phakic and aphakic is post-SOT refraction. In pseudophakic, gender and diagnosis of RRD are the predictors of SOR refraction.