Changes In Axial Length Research Articles

TEN-YEAR LONGITUDINAL MORPHOLOGIC CHANGES IN DOME-SHAPED MACULAS IN HIGHLY MYOPIC EYES.

To determine the longitudinal changes in the morphologic features of dome-shaped macula in highly myopic eyes. Patients with a dome-shaped macula and high myopia (spherical equivalent <-8 diopters [D] or axial length ≥26.5 mm) were retrospectively studied. The medical records, optical coherence tomographic images, and ultra-widefield optical coherence tomography images were analyzed. A total of 113 eyes of 82 patients were studied with a mean follow-up of 122.32 ± 6.36 months. During the follow-up, the mean dome height was significantly increased from 181.51 ± 105.55 to 209.85 ± 130.84 µ m ( P < 0.001). There was also a significant increase in the axial length (30.83 ± 1.82-31.16 ± 1.86 mm; P < 0.001). Subgroup analyses showed that the dome height increased more than 50 µ m in 78 (69%) eyes, decreased in 23 (20%) eyes, and was stable in 12 (11%) eyes. The change in the axial lengths was significantly greater in the increased dome height group than in the decreased and stable dome height groups ( P = 0.042). Multivariable analysis showed that the greater axial length change (OR, 8.73; P = 0.017) and horizontal type dome-shaped macula (OR, 4.14; P = 0.026) were significantly associated with an increase in dome height. The direction of change in the dome-shaped macula height varies and 69% of the eyes had an increase in height, whereas 20% of the eyes had a decrease in height. The variations in the dome height may result from the difference between the deepening of the peridome scleral excavation and the changes of the axial length.

Longitudinal Changes in Axial Length and Spherical Equivalent in Children and Adolescents With High Myopia.

To investigate longitudinal changes in axial length (AL) and spherical equivalent (SE) in children and adolescents with high myopia and to explore associated risk factors. This was a longitudinal, observational cohort study of highly myopic participants (aged 7-17 years) to evaluate the mean rates of change in AL and SE. Mixed effects regression models were used to explore the risk factors. The sample consisted of 293 participants (mean age at the baseline, 13.63 ± 2.66 years; mean AL, 27.03 ± 1.30mm diopters; mean SE, -8.99 ± 2.30 diopters) who were followed for 7.09 ± 1.64 years. Pathological myopia (PM) was present in 11.95% of the participants at the baseline. Over the follow-up period, the mean AL and SE progression rates were 0.13mm/y (95% CI, 0.12-0.14) and -0.36 diopters/y (95% CI, -0.39 to -0.34). The multivariate analysis showed that the AL elongation and myopic SE progression decreased significantly after age 11 (β = -0.080, P < 0.001; β = 0.146, P < 0.001), increased with a greater baseline SE (β = -0.006, P = 0.014; β = 0.017, P = 0.005), and accelerated in children and adolescents who had PM at the baseline (β = 0.043, P = 0.011; β = -0.097, P = 0.025). A significant association was found between acceleration of AL elongation and myopic SE progression among the children and adolescents with age, especially those younger than 11 years, and the presence of PM.

A Meta-Analysis of Myopia Control with MiSight 1 Day Contact Lenses

The purpose of this research (PROSPERO Registration No. CRD42023396866) is to evaluate efficacy of MiSight 1 Day Contact Lenses (CooperVision) for controlling myopia progression. Data were researched from search in PubMed, MEDLINE, EMBASE, Web of Science and Cochrane Library ended on February 3, 2023. Our meta-analyses included three RCTs and one retrospective study and covered 470 eyes which have tested the efficacy of MiSight. The research results include the changes of refractive errors (spherical equivalent refraction) and axial length from the beginning of intervention to the end of follow-up. The weighted mean difference (WMD) of the change of spherical equivalent refraction (SER) in MiSight groups and control groups were 0.098D (95% CI, 0.006-0.189, p = 0.037) in 6 months, 0.353D (95% CI, 0.261-0.445, p &lt; 0.0001) in 12 months and 0.432D (95% CI, 0.181-0.683, p = 0.001) in 24 months. The weighted mean difference (WMD) of change of axial length (AL) in MiSight groups and control group were 0.098D (95% CI, 0.006-0.189, p = 0.037) in 6 months, 0.353D (95% CI, 0.261-0.445, p &lt; 0.0001) in 12 months and 0.432D (95% CI, 0.181-0.683, p = 0.001) in 24 months. This meta-analysis suggests that MiSight is effectual on Myopia control.

Retrospective Analysis of Axial Length Changes in Overnight Orthokeratology in an Academic Myopia Control Clinic.

Although the myopia control efficacy of orthokeratology lenses has been established with clinical trials, reports of axial length change in non-study-based patient care are scarce. This study investigates the use of orthokeratology lenses for myopia control in a clinical population and compares axial elongation against those published in recent clinical investigations. This study aimed to investigate factors affecting axial elongation during use of orthokeratology lenses for myopia control in an academic clinical setting. This study was a retrospective consecutive case series from the Myopia Control Clinic at the Herbert Wertheim School of Optometry at the University of California, Berkeley (Berkeley, CA). Patients ranging from 5 to 18 years old using orthokeratology for at least 1 year were included in the study. Data from 102 patients' eyes were analyzed at baseline (before the initiation of treatment) and after 1 year of wear (12 ± 3 months). Multivariate analysis was undertaken to identify factors significantly associated with axial elongation over this period. Mean (±standard deviation) spherical equivalent refraction and axial length at baseline were -2.54 (±1.21) D and 24.53 (±0.82) mm, respectively. By the 1-year follow-up, eyes had shown significant axial elongation (0.18 ± 0.24 mm; P < .001), which was found to be inversely correlated with age ( P < .001). Race, sex, baseline axial length, and baseline refraction were not significantly associated with axial elongation. Factors influencing axial length and the magnitude of axial elongation in our orthokeratology patient population are consistent with orthokeratology treatment groups from published randomized clinical trials and support the use of these lenses for myopia control in a clinical practice setting.

Efficacy of Different Powers of Low-Level Red Light in Children for Myopia Control

To compare the efficacy and safety of low-level red light (LRL) in controlling myopia progression at 3 different powers: 0.37 mW, 0.60 mW, and 1.20 mW. Single-center, single-masked, randomized controlled trial. Two hundred children aged 6-15 with myopia of -0.50 diopter (D) or more and astigmatism of -2.50 D or less were enrolled from April to May 2022. Follow-up ended in December2022. Participants were assigned randomly to 3 intervention groups and 1 control group (1:1:1:1). All participants wore single-vision spectacles. Moreover, the intervention group randomly received LRL at 3 different powers twice daily for 3 minutes per session, with a minimum 4-hour interval. Changes in spherical equivalent (SE), axial length (AL), and subfoveal choroidal thickness (SFCT) were measured. After 6 months, SE progression was significantly lower in the 0.37-mW group (0.01 D; 95% confidence interval [CI], -0.12 to 0.15), 0.60-mW group (-0.05 D; 95% CI, -0.18 to 0.07), and 1.20-mW group (0.16D; 95% CI, 0.03 to 0.30) compared to the control group (-0.22 D; 95% CI, -0.50 to 0.30; adjusted P<0.001 for all). AL changes in the 0.37-mW group (0.04 mm; 95% CI, -0.01 to 0.08), 0.60-mW group (0.00 mm; 95% CI, -0.05 to 0.05), and 1.20-mW group (-0.04 mm; 95% CI, -0.08 to 0.01) were significantly smaller than the control group (0.27 mm; 95% CI, 0.22 to 0.33; adjusted P < 0.001 for all). Similarly, increases in SFCT were significantly greater in the 0.37-mW group (22.63 μm; 95% CI, 12.13 to 33.34 μm), 0.60-mW group (36.17 μm; 95% CI, 24.37 to 48.25 μm), and 1.20-mW group (42.59 μm; 95% CI, 23.43 to 66.24 μm) than the control group (-5.07 μm; 95% CI, -10.32 to -0.13 μm; adjusted P < 0.001 for all). No adverse events were observed. LRL effectively controlled myopia progression at 0.37 mW, 0.60 mW, and 1.20 mW. Further research is required. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Efficacy and Safety Evaluation of Scleral Cross-Linking Using Genipin in the Treatment of Juvenile Guinea Pigs with High Myopia.

Purpose: To investigate the efficacy and safety of scleral cross-linking (CXL) using Genipin in the treatment of juvenile guinea pigs with high myopia. Methods: Twenty-four 4-week-old tricolor guinea pigs with high myopia of diopter ≤ -6.0 DS in the right eye were randomly divided into two groups: Genipin CXL group and control group (n = 12 for each group). They received separately form-deprivation (FD) combined with sub-tenon injection, and the former was 0.5% Genipin solution, while the latter was 0.9% saline solution. Refractive error, axial length (AL), intraocular pressure (IOP), and structural and vasculature optic disc changes in optical coherence tomography (OCT) and OCT angiography (OCTA) were analyzed at baseline and at 3 weeks after injection. Results: Baseline parameters were similar between the two groups (P > 0.05). After 3 weeks of the intervention, the difference of AL between the two groups was statistically significant (t = -11.28, P < 0.001). Besides, IOP increased in both groups, and the changes of IOP between the two groups were statistically significant (t = 2.80, P = 0.01). The average cup-disc ratio (C/D) (t = 3.11, P = 0.006) and the vertical C/D (t = 2.96, P = 0.009) of OCT-related optic disc parameters in the Genipin CXL group increased, and the differences were statistically significant compared with the control group. Conclusion: The CXL method of sub-tenon injection of Genipin solution could effectively inhibit the progression of myopia in juvenile guinea pigs with highly myopic eyes combined with FD. The slightly elevated IOP and increased C/D of some fundus optic discs should be further assessed.

High myopia control is comparable between multifocal rigid gas-permeable lenses and spectacles.

Ocular pathology may be reduced by slowing myopia progression. The purpose of this study was to evaluate the potential of a novel custom-designed rigid gas permeable (RGP) contact lens to control high myopia by comparing the efficacy of multifocal RGP lenses and single-vision spectacles for high myopia control. The medical records of children fitted with spectacles or multifocal rigid gas-permeable lenses between January 2018 and May 2020 were retrospectively reviewed. Children (5-17 years) with non-cycloplegic spherical equivalent refraction of ≤ -6.00 D or spherical equivalent refraction > - 6.00 D with baseline axial length ≥ 26.5 mm, and astigmatism of ≥ -2.00 D were included. Axial length and refraction were measured at baseline, before fitting the participants with multifocal rigid gas-permeable lenses or spectacles, and at 1- and 2-year follow-up visits. Changes in axial length were compared between the groups. Among the 77 children with 1-year follow-up data, the mean axial elongation was 0.20 ± 0.17 mm and 0.21 ± 0.14 mm in the multifocal rigid gas-permeable and control groups, respectively, without significant differences between groups (F = 0.004, p = 0.835). Among the 41 patients who completed 2 years of follow-up, the mean axial elongation values in the multifocal rigid gas-permeable and control groups were 0.21 ± 0.15 mm and 0.24 ± 0.13 mm, respectively, at the 1-year follow-up, and 0.37 ± 0.27 mm and 0.43 ± 0.23 mm, respectively, at the 2-year follow-up, without significant between-group differences at either time point (p = 0.224). Axial length increased at a similar rate in both the control (spectacles) and multifocal rigid gas-permeable lens groups, suggesting that multifocal rigid gas-permeable lenses have no significant impact on controlling high myopia progression compared with spectacles.

Repeated Low-Level Red Light Therapy for the Control of Myopia in Children: A Meta-Analysis of Randomized Controlled Trials.

Repeated low-level red light (RLRL) therapy has been suggested to be effective in children with myopia. However, evidence from randomized controlled trials (RCTs) is still limited. We performed a meta-analysis of RCTs to systematically evaluate the efficacy of RLRL on changes of axial length (AL) and cycloplegic spherical equivalent refraction (SER) in children with myopia. Relevant RCTs were obtained through a search of electronic databases including PubMed, Embase, Cochrane Library, Wanfang, and China National Knowledge Infrastructure from inception to September 15, 2022. A random-effects model was used to pool the results after incorporating the influence of potential heterogeneity. Subgroup analyses were performed according to the control treatment and follow-up duration. A total of seven RCTs involving 1,031 children with myopia, aged 6 to 16 years, were included in the meta-analysis. Compared with control treatment without RLRL, treatment with RLRL was associated with a significantly reduced AL (mean difference [MD]: -0.25 mm, 95% confidence interval [CI]: -0.32 to -0.17, P<0.001; I2=13%) and a significantly increased cycloplegic SER (MD: 0.60 D, 95% CI: 0.44-0.76, P<0.001; I2=20%). Further subgroup analyses showed consistent results in studies comparing children wearing single vision lenses and those receiving active treatment including orthokeratology or low-dose atropine eye drops, as well as studies of treatment duration of 6 and 12 months. Results of the meta-analysis suggested that RLRL treatment is effective for slowing down the progression of myopia in children aged 6 to 16 years.

Effect of Low-Concentration Atropine Eye Drops in Controlling the Progression of Myopia in Children: A One- and Two-Year Follow-Up Study

ABSTRACT Purpose Atropine eye drops have been shown to slow the progression of myopia, but there has been limited research on the effectiveness of 0.05% atropine in treating myopia. This study aimed to investigate the safety and efficacy of 0.05% atropine eye drops in controlling myopia in children. Methods The study included 424 participants aged 6 to 12 years between January 1, 2015, and January 1, 2021. Of these, 213 were randomly assigned to the 0.05% atropine group and 211 to the placebo group. The cycloplegic spherical equivalent (SE), axial length (AL), corneal curvature (K), and anterior chamber depth (ACD) were measured using IOLMaster. The lens power and corneal astigmatism were also determined. The changes in ocular biometric parameters were compared between the two groups, and the contributions of ocular characteristics to SE progression were calculated and compared. Results Over a 12-month period, the changes in spherical equivalent were −0.03 ± 0.28 and −0.32 ± 0.14 in the atropine and placebo groups, respectively (P = .01). The changes in axial length were 0.06 ± 0.11 and 0.17 ± 0.12, respectively (P = .01). At 18 and 24 months, there were significant differences in axial length and spherical equivalent between the atropine and placebo groups. Multiple regression models accounting for changes in AL, K, and lens magnification explained 87.23% and 98.32% of SE changes in the atropine and placebo groups, respectively. At 1 year (p = .01) and 2 years (p = .03), there were significant differences in photophobia between the atropine and placebo groups. Conclusions This two-year follow-up study demonstrates that 0.05% atropine eye drops are safe and effective in preventing the development of myopia in school-aged children.

Temporal Optic Disc Microvasculature Dropout in Glaucoma.

To assess the clinical characteristics of focal temporal optic disc microvasculature dropout (MvD-D) in primary open-angle glaucoma (POAG) patients. One hundred and eighty-seven eyes of 187 POAG patients having MvD-D on Swept-Source optical coherence tomography angiography (SS-OCTA) were enrolled. Three groups were categorized according to the presence of temporal MvD-D within the upper and lower 45° of the fovea-Bruch's membrane (BM) opening axis: focal temporal MvD-D (Group 1, isolated focal temporal MvD-D; 44 eyes), supero/inferotemporal MvD-D (Group 2, MvD-D only in superotemporal or inferotemporal sector; 78 eyes), and diffuse temporal MvD-D (Group 3, MvD-D spanning ≥ 2 consecutive sectors, at least one of which being temporal sector; 65 eyes). Group 1 had a significantly longer axial length and β-zone parapapillary atrophy without BM. There also was a larger horizontal tilt angle and ovality index than the other two groups (P < 0.001). Group 1 had a significantly thinner retinal nerve fiber layer (RNFL) in the temporal sector than did Group 2 (P < 0.001), despite similar thicknesses in all other areas (P > 0.05). Group 3 had significantly worse visual field mean deviation and thinner RNFL than the other two groups in all areas other than the nasal, temporal, and superotemporal sectors (P < 0.05). Focal temporal MvD-D detected by SS-OCTA was associated with a longer axial length and related subsequent morphological changes of the optic disc and parapapillary area. This suggests that stretching of the optic disc consequent on axial elongation may lead to absence of temporal optic disc microvasculature.

Outdoor Scene Classrooms to Arrest Myopia: Design and Baseline Characteristics.

This study aimed to investigate the impact on childhood myopia of classrooms with spatial properties of classrooms resembling those of outdoor environments. This article describes the design, baseline characteristics, and the acceptability of this strategy. Classrooms had custom-made wallpaper installed with forest and sky scenes that had spatial frequency spectra comparable with outdoor environments (i.e., outdoor scene classrooms). Acceptability of this strategy was evaluated by questionnaires. Outcomes to access the efficacy include cumulative proportion of myopia, change of cycloplegic spherical equivalent refractive error, and axial length. Ten classes, comprising 520 students, were randomly assigned into outdoor scene or tradition classrooms. There was no difference in refractive status between two groups (myopia/emmetropia/hyperopia, 16.3% vs. 49.4% vs. 34.2% in outdoor scene classrooms, 18.3% vs. 49.0% vs. 32.7% in traditional classrooms; P = .83). Compared with the traditional classrooms, 88.9% of teachers and 87.5% of students felt the outdoor scene classrooms enjoyable, 22.2% of teachers and 75.3% of students reported higher concentration, and 77.8% of teachers and 15.2% of students reported no change. In addition, 44.4% of teachers and 76.0% of students reported higher learning efficiency in the outdoor scene classrooms, and 55.6% of teachers and 18.3% of students reported no change. Outdoor scene classrooms are appealing to teachers and students. Outcomes of the study will inform the efficacy of this strategy in Chinese children.

Low-Dose 0.01% Atropine Eye Drops vs Placebo for Myopia Control

Controlling myopia progression is of interest worldwide. Low-dose atropine eye drops have slowed progression in children in East Asia. To compare atropine, 0.01%, eye drops with placebo for slowing myopia progression in US children. This was a randomized placebo-controlled, double-masked, clinical trial conducted from June 2018 to September 2022. Children aged 5 to 12 years were recruited from 12 community- and institution-based practices in the US. Participating children had low to moderate bilateral myopia (-1.00 diopters [D] to -6.00 D spherical equivalent refractive error [SER]). Eligible children were randomly assigned 2:1 to 1 eye drop of atropine, 0.01%, nightly or 1 drop of placebo. Treatment was for 24 months followed by 6 months of observation. Automated cycloplegic refraction was performed by masked examiners. The primary outcome was change in SER (mean of both eyes) from baseline to 24 months (receiving treatment); other outcomes included change in SER from baseline to 30 months (not receiving treatment) and change in axial length at both time points. Differences were calculated as atropine minus placebo. A total of 187 children (mean [SD] age, 10.1 [1.8] years; age range, 5.1-12.9 years; 101 female [54%]; 34 Black [18%], 20 East Asian [11%], 30 Hispanic or Latino [16%], 11 multiracial [6%], 6 West/South Asian [3%], 86 White [46%]) were included in the study. A total of 125 children (67%) received atropine, 0.01%, and 62 children (33%) received placebo. Follow-up was completed at 24 months by 119 of 125 children (95%) in the atropine group and 58 of 62 children (94%) in the placebo group. At 30 months, follow-up was completed by 118 of 125 children (94%) in the atropine group and 57 of 62 children (92%) in the placebo group. At the 24-month primary outcome visit, the adjusted mean (95% CI) change in SER from baseline was -0.82 (-0.96 to -0.68) D and -0.80 (-0.98 to -0.62) D in the atropine and placebo groups, respectively (adjusted difference = -0.02 D; 95% CI, -0.19 to +0.15 D; P = .83). At 30 months (6 months not receiving treatment), the adjusted difference in mean SER change from baseline was -0.04 D (95% CI, -0.25 to +0.17 D). Adjusted mean (95% CI) changes in axial length from baseline to 24 months were 0.44 (0.39-0.50) mm and 0.45 (0.37-0.52) mm in the atropine and placebo groups, respectively (adjusted difference = -0.002 mm; 95% CI, -0.106 to 0.102 mm). Adjusted difference in mean axial elongation from baseline to 30 months was +0.009 mm (95% CI, -0.115 to 0.134 mm). In this randomized clinical trial of school-aged children in the US with low to moderate myopia, atropine, 0.01%, eye drops administered nightly when compared with placebo did not slow myopia progression or axial elongation. These results do not support use of atropine, 0.01%, eye drops to slow myopia progression or axial elongation in US children. ClinicalTrials.gov Identifier: NCT03334253.

Comparison of myopia progression among Chinese schoolchildren before and during COVID-19 pandemic: a meta-analysis.

To compare myopia progression in Chinese schoolchildren before and after the COVID-19 pandemic home confinement. This study was done through the data searched from PubMed, Embase, Cochrane Library, and Web of Science from January 2022 to March 2023 related to the COVID-19 pandemic home confinement and myopia progression among Chinese schoolchildren. Myopia progression was evaluated by the mean change of spherical equivalent refraction (SER) and axial length (AL) before and during the COVID-19 pandemic. Sex and regional differences in myopia progression among schoolchildren before and during the COVID-19 pandemic were also analyzed. A total of eight eligible studies were included in this study. There was a significant difference in SER before and during home confinement during the COVID-19 pandemic (OR = 0.34; 95%CI = [0.23, 0.44]; Z = 6.39; P < 0.00001), but no significant difference in AL (OR = 0.16; 95%CI = [-0.09, 0.41]; Z = 1.22, P = 0.22). There was a significant difference in SER between male and female groups during the COVID-19 home confinement (OR = 0.10; 95%CI = [0.00, 0.19]; Z = 1.98, P = 0.05). As for regional analysis, there was a significant difference in SER between urban and rural areas during the COVID-19 quarantine period (OR = -0.56; 95%CI = [-0.88, -0.25]; Z = 3.50, P = 0.0005). Compared with the time before the COVID-19 home confinement, a higher rate of myopic progression among Chinese schoolchildren during the period of the COVID-19 pandemic was demonstrated.

Multiple segment spectacle lenses for myopia control. Part 2: Impact on myopia progression.

Initial studies have suggested that multiple segment (MS) spectacle lenses can reduce the progression rate of childhood myopia and axial eye growth. This paper aimed to compare the effectiveness of two different available designs of MS lens and to explore the nature of their control effect. Published data from the only two clinical trials in which changes in mean spherical equivalent refraction (SER) and axial length (AL) for matched groups of myopic children wearing either MS or single-vision (SV) spectacle corrections, recorded over a period of at least 2 years, were further analysed and compared. Both trials involved Chinese children of similar ages and visual characteristics, but the trials were located in different cities. The two MS lenses examined were MiyoSmart or DIMS (Hoya) and Stellest (Essilor). Absolute changes in SER and AL differed over time during the two trials. However, if the results were expressed in terms of efficacy over successive 6-month periods, then the two MS lenses produced broadly similar results (initial efficacy for the control of myopia progression of about 60%-80%, declining over 2 years to about 35%-55%). Control appears to be absolute rather than proportional. Myopia control may be due to either the additional myopic defocus induced by the MS lenses (i.e., asymmetry of the through-focus image changes about the distance focus) or to the general reduction in image contrast that the lenslets create in the peripheral field. Multiple segment spectacle lenses offer a valuable new approach to the control of myopia progression in children. Further work is required to clarify their mechanism of action and to optimise their design parameters.

Effects of orthokeratology lenses on tear film and tarsal glands and control of unilateral myopia in children.

Introduction: To investigate the effects of an orthokeratology lens on the tear film and tarsal glands and myopia control in children with unilateral myopia using an intelligent analysis model. Methods: We retrospectively reviewed the medical records from November 2020 to November 2022 of 68 pediatric patients with unilateral myopia in Fujian Provincial Hospital who had been wearing an orthokeratology lens for more than 1year. The 68 myopic eyes were included in the treatment group, while the 68 healthy, untreated contralateral eyes were included in the control group. Tear film break-up times (TBUTs) were compared between the two groups at various intervals, and an intelligent analysis model was used to compare the deformation coefficients of 10 meibomian glands in the central area and the different positions of the glands in the two groups after 12months of treatment. Changes in axial length and equivalent spherical power were also compared between the groups before and after 12months of treatment. Results: In the treatment group, TBUTs differed significantly between 1 and 12months after treatment, although no significant differences from baseline were observed at 3 or 6months. No significant differences in TBUTs were observed at any time point in the control group. After 12months of treatment, significant between-group differences were observed for glands 2, 3, 4, 5, 6, 7, 8, and 10 (numbered from the temporal to nasal regions). The treatment group also exhibited significant differences in deformation coefficients at different detection positions in the central region, with glands 5 and 6 exhibiting the highest deformation coefficients. Increases in axial length and equivalent spherical power were significantly greater in the control group than in the treatment group after 12months of treatment. Discussion: Wearing orthokeratology lenses at night can effectively control myopia progression in children with unilateral myopia. However, long-term use of these lenses may lead to meibomian gland deformation and impact tear film function, and the extent of deformation may vary at different positions in the central region.

Six-month repeated irradiation of 650nm low-level red light reduces the risk of myopia in children: a randomized controlled trial.

To evaluate whether the six-month repeated irradiation of 650nm low-level red light (LLRL) decreases the risk of myopia onset in children. This was a single-masked, randomized controlled trial. A total of 112 children (aged 6-12years) were enrolled and randomized to the treatment group or control group in a 1:1 ratio. The cycloplegic spherical equivalent error (SER) of children at baseline was -0.5 diopter (D) to 3D. Children in the treatment group were irradiated with the 650nm LLRL for 6 min daily. No intervention was given to the control. The primary outcomes are myopia incidence, change in cycloplegic SER, and change in axial length (AL). For the treatment group and control group, the six-month myopia incidence rates were 1.8% (95% confidence interval, CI: 0.2-4.9%) and 12.5% (95% CI: 5.5-21.9%), respectively. The difference was significant (p = 0.028). The median changes in AL for the treatment group and control group were -0.02 (interquartile range, IQR: -0.12 to 0.06) mm, and 0.09 (IQR: 0-0.18) mm, respectively. The difference was significant (p < 0.001). The median changes in cycloplegic SER for the treatment group and control group were 0 (IQR: 0-0.25) D, and -0.125 (IQR: -0.375 to 0) D, respectively. The difference was significant (p < 0.001). There was no adverse event. The repeated irradiation of 650nm LLRL may have a strong effect for myopia prevention in children, without risk of adverse events. this trial is retrospectively registered in the Chinese Clinical Trial Registry ( http://www.chictr.org.cn/ ), the registration number is ChiCTR2200058963.

Short-Term Axial Length Changes in Myopic Eyes Induced by Defocus Spectacles for Myopia Control

Background. This study tested short-term axial length changes with Lenstar using a simple peripheral plus-add spectacle design. Methods. The subjects for this study were current users of monofocal glasses or contact lenses, aged 18–25 years, with myopic spherical refractions ranging from −1.00 to −5.00 diopters in both eyes. This study tested subjects while using a pair of special defocus spectacles that possess a central zone with the distance myopic correction and a peripheral zone with +3.50 added diopters. The procedure consisted of reading an online book with black letters on white background on a desktop computer, in two periods—one with the usual spectacles and the second with special defocus spectacles. Before and after these periods, 10 axial length measurements of the right eye were made with Lenstar and averaged up to three decimal points. Results. Seventeen subjects (thirteen female and four male; mean age 22.3 ± 5.5 years) participated in this study. The mean spherical equivalent of their right eye was −2.31 ± 1.06 diopters. There was a significant difference of +8.1 microns which increased the axial length from baseline when reading the usual prescription levels during the first 40 min period. When subjects read in the same situation with the defocus spectacles, the axial length significantly returned to baseline measurements, which were shortened by −10.6 microns. Conclusions. The decrease in axial length with these spectacles might indicate an effect on axial elongation signals from the choroid. These spectacles could be tested for myopia control purposes.

Prediction of spherical equivalent refraction and axial length in children based on machine learning.

Recently, the proportion of patients with high myopia has shown a continuous growing trend, more toward the younger age groups. This study aimed to predict the changes in spherical equivalent refraction (SER) and axial length (AL) in children using machine learning methods. This study is a retrospective study. The cooperative ophthalmology hospital of this study collected data on 179 sets of childhood myopia examinations. The data collected included AL and SER from grades 1 to 6. This study used the six machine learning models to predict AL and SER based on the data. Six evaluation indicators were used to evaluate the prediction results of the models. For predicting SER in grade 6, grade 5, grade 4, grade 3, and grade 2, the best results were obtained through the multilayer perceptron (MLP) algorithm, MLP algorithm, orthogonal matching pursuit (OMP) algorithm, OMP algorithm, and OMP algorithm, respectively. The R2 of the five models were 0.8997, 0.7839, 0.7177, 0.5118, and 0.1758, respectively. For predicting AL in grade 6, grade 5, grade 4, grade 3, and grade 2, the best results were obtained through the Extra Tree (ET) algorithm, MLP algorithm, kernel ridge (KR) algorithm, KR algorithm, and MLP algorithm, respectively. The R2 of the five models were 0.7546, 0.5456, 0.8755, 0.9072, and 0.8534, respectively. Therefore, in predicting SER, the OMP model performed better than the other models in most experiments. In predicting AL, the KR and MLP models were better than the other models in most experiments.

Change in major ocular biometry parameters axial length and keratometry in adults over time.

The goal of this study was to determine how much axial length (AL) and average keratometry (KER) change over time in elderly patients and to assess clinical necessity of repeating biometry in instances where the second eye is operated on 6 months or more after the first. Northwestern Memorial Hospital, Chicago, IL, U.S. Retrospective study of biometry data measured with the IOL Master 700 (Zeiss, Germany) from January 1, 2016 to September 15, 2020. Inclusion criteria were patients over 35 years, with two biometry measurements over 6 months apart. Patients were excluded if they had any other intraocular surgery besides cataract. A linear mixed model and SPSS software was used to compare measurements among time points. A total of 201 patients (402 eyes) were included (average age 73.3, 59.3% female). Average time between biometry measurements was 21.5 months (range 6-48 months). The mean change in AL was 0.04 mm (95% CI: 0.03 to 0.05, p=0.10). The mean change in KER was 0.01 D (95% CI: -0.10 to 0.30, p=0.33). At the 6 months to 1-year interval (n=73), mean change in AL was 0.04 mm. Mean change in AL did not significantly increase with greater time intervals. There was no correlation between time and ΔAL (p=0.70), nor between time and ΔKER (p=0.98). In our cohort, biometric parameters did not change significantly over time. Repeating biometry at a 1 to 2-year interval for elderly patients receiving monofocal implants may offer limited benefit.

Effectiveness of 0.01% atropine in anisomyopic children

Purpose: To investigate the change in ocular parameters of anisomyopic children treated with 0.01% atropine. Methods: This retrospective study analyzed the data of anisomyopic children who underwent comprehensive examination at a tertiary eye center in India. Anisomyopic subjects (difference of ≥1.00 D) of age 6–12 years who were treated with 0.01% atropine or prescribed regular single vision spectacle and had follow-ups of more than 1 year were included. Results: Data from 52 subjects were included. No difference was observed in the mean rate of change of spherical equivalent (SE) of more myopic eyes between 0.01% atropine (−0.56 D; 95% confidence interval [CI]: −0.82, −0.30) and single vision lens wearers (−0.59 D; 95% CI: −0.80, −0.37; P = 0.88). Similarly, insignificant change in the mean SE of less myopic eyes was noted between the groups (0.01% atropine group, −0.62 D; 95% CI: −0.88, −0.36 vs. single vision spectacle wearer group, −0.76 D; 95% CI: −1.00, −0.52; P = 0.43). None of the ocular biometric parameters showed any difference between the two groups. Though anisomyopic cohort treated with 0.01% atropine revealed a significant correlation between the rate of change of mean SE and axial length in both eyes (more myopic eyes, r = −0.58; P = 0.001 and less myopic eyes, r = −0.82; P < 0.001) compared to single vision spectacle wearer group, the change was not significant. Conclusion: Administration of 0.01% atropine had minimal effect on reducing the rate of myopia progression in anisomyopic eyes.