The efficacy of orthokeratology lenses with smaller back optic zone diameter in myopia control. A meta-analysis.

PURPOSE: This study was conducted to determine whether orthokeratology (OK) lenses with a smaller back optic zone diameter (BOZD) could exhibit stronger myopia control effects. METHOD: A meta-analysis was registered in PROSPERO (CRD42023408184). A comprehensive systematic database search was conducted, encompassing PubMed, Cochrane Library, EMBASE, MEDLINE, Web of Science, Ovid, CNKI and CBM, to identify relevant studies up to 25 March 2023. The primary inclusion criteria for this meta-analysis were studies that investigated the myopia control effect of OK lenses with a small optical treatment area (≤5 mm). To assess the quality of the retrieved articles, two researchers evaluated them using the Cochrane bias risk assessment criteria. The primary outcome measures were the changes in axial length (AL) and refractive error, using the weighted mean differences (WMD) and 95% confidence intervals (CI) to assess differences between small and traditional back optical treatment zone groups in terms of these outcomes. RESULTS: The analysis encompassed five eligible studies, with a 1 year duration. The average difference in AL between the groups was 0.12 mm (WMD = -0.12, 95% CI [-0.16, -0.09], p < 0.00001). Likewise, the average difference in refractive error between the two groups was 0.44 D (WMD = 0.44, 95% CI [0.30, 0.57], p < 0.00001). None of the studies reported severe adverse events. CONCLUSIONS: Current evidence suggests that OK lenses with smaller back optical treatment zone are more effective in preventing myopia progression than traditional lenses. However, a longer-term evaluation is warranted.

Artificial Intelligence-Assisted Prescription Determination for Orthokeratology Lens Fitting: From Algorithm to Clinical Practice.

OBJECTIVES: To explore the potential of artificial intelligence (AI) to assist prescription determination for orthokeratology (OK) lenses. METHODS: Artificial intelligence algorithm development followed by a real-world trial. A total of 11,502 OK lenses fitting records collected from seven clinical environments covering major brands. Records were randomly divided in a three-way data split. Cross-validation was used to identify the most accurate algorithm, followed by an evaluation using an independent test data set. An online AI-assisted system was implemented and assessed in a real-world trial involving four junior and three senior clinicians. RESULTS: The primary outcome measure was the algorithm's accuracy (ACC). The ACC of the best performance of algorithms to predict the targeted reduction amplitude, lens diameter, and alignment curve of the prescription was 0.80, 0.82, and 0.83, respectively. With the assistance of the AI system, the number of trials required to determine the final prescription significantly decreased for six of the seven participating clinicians (all P <0.01). This reduction was more significant among junior clinicians compared with consultants (0.76±0.60 vs. 0.32±0.60, P <0.001). Junior clinicians achieved clinical outcomes comparable to their seniors, as 93.96% (140/149) and 94.44% (119/126), respectively, of the eyes fitted achieved unaided visual acuity no worse than 0.8 ( P =0.864). CONCLUSIONS: AI can improve prescription efficiency and reduce discrepancies in clinical outcomes among clinicians with differing levels of experience. Embedment of AI in practice should ultimately help lessen the medical burden and improve service quality for myopia boom emerging worldwide.

Burdens and trends of blindness and vision loss among those aged 55 years and older: A systematic analysis for the Global Burden of Disease Study 2019.

PURPOSE: To systematically analysis the burden and trends of blindness and vision loss for those aged ≥55 years from 1990 to 2019 and to predict trends over the next few years. METHODS: The data were extracted from the Global Burden of Disease Study (GBD) 2019. Trends from 1990 to 2019 were calculated using average annual percentage change (AAPC) by joinpoint regression analysis. Bayesian age-period-cohort (BAPC) models were used to predict future trends. RESULTS: In 2019, the global prevalence of blindness and vision loss was 471.1 million with 15.9 million disability-adjusted life-years (DALYs) for those aged ≥55 years. These numbers will reach 640.3 million cases and 18.9 million DALYs in 2030. The prevalence rate (per 100,000 population) increased from 32,137.8 (95% uncertainty interval [UI], 26,307.9-39,246.3) in 1990 to 33,509 (95% UI, 27,435.5-40,996.2) in 2019, with an AAPC of 0.143 (95% confidence interval [CI], 0.125-0.161; P < 0.001). The DALY rate (per 100,000 population) decreased from 632.9 (95% UI, 447.7-870.9) in 1990 to 579.3 (95% UI, 405.2-803.4) in 2019, with an AAPC of -0.293 (95% CI, -0.323-[-]0.263). Although the prevalence rates of cataracts, age-related macular degeneration, glaucoma, and near vision loss showed increasing trends from 1990 to 2019, the DALY rates indicated a downward trend for all blindness-causing diseases. The burden is heavier for women and in low Socio-demographic Index (SDI) regions. CONCLUSIONS: Despite a decline from 2001 to 2019, the burden of blindness and vision loss, measured by prevalence and DALYs, continues to rise after adjusting for population growth and aging. Blindness and vision loss are significant public health burdens, especially for women and in low-SDI regions.

CCDC66 mutations are associated with high myopia through affected cell mitosis.

BACKGROUND: High myopia (HM) refers to an eye refractive error exceeding -5.00 D, significantly elevating blindness risk. The underlying mechanism of HM remains elusive. Given the extensive genetic heterogeneity and vast genetic base opacity, it is imperative to identify more causative genes and explore their pathogenic roles in HM. METHODS: We employed exome sequencing to pinpoint the causal gene in an HM family. Sanger sequencing was used to confirm and analyse the gene mutations in this family and 200 sporadic HM cases. Single-cell RNA sequencing was conducted to evaluate the gene's expression patterns in developing human and mouse retinas. The CRISPR/Cas9 system facilitated the gene knockout cells, aiding in the exploration of the gene's function and its mutations. Immunofluorescent staining and immunoblot techniques were applied to monitor the functional shifts of the gene mutations at the cellular level. RESULTS: A suspected nonsense mutation (c.C172T, p.Q58X) in CCDC66 was found to be co-segregated with the HM phenotype in the family. Additionally, six other rare variants were identified among the 200 sporadic patients. CCDC66 was consistently expressed in the embryonic retinas of both humans and mice. Notably, in CCDC66-deficient HEK293 cells, there was a decline in cell proliferation, microtube polymerisation rate and ace-tubulin level. Furthermore, the mutated CCDC66 failed to synchronise with the tubulin system during Hela cell mitosis, unlike its wild type counterpart. CONCLUSIONS: Our research indicates that the CCDC66 variant c.C172T is associated with HM. A deficiency in CCDC66 might disrupt cell proliferation by influencing the mitotic process during retinal growth, leading to HM.

Effect of mount location on the quantification of light intensity in myopia study.

PURPOSE: To investigate how the mounting location of wearable devices affects the measurement of light intensity. METHODS: Two commercially available wearable devices, HOBO and Clouclip, were used to compare the effects of different mount locations on light intensity measurement. We assessed the consistency of the measurements of the two devices by placing a HOBO and a Clouclip simultaneously in 26 different light environments and measuring the light intensity. To simulate the real-life usage scenarios of the two devices, we had 29 participants wear two HOBOs-one on the wrist and the other on the chest-along with a Clouclip on their spectacles for 1 day; meanwhile, the light intensity was measured and analysed. RESULTS: When under the same light environments, the light intensity measured by the Clouclip was 1.09 times higher than that by the HOBO, with an additional 82.62 units (r2=1.00, p<0.001). When simulating the real-life scenarios, the mean light intensity at the eye-level position was significantly lower than that at the chest position (189.13±665.78 lux vs 490.75±1684.29 lux, p<0.001) and the wrist position (189.13±665.78 lux vs 483.87±1605.50 lux, p<0.001). However, there was no significant difference in light intensity between the wrist and chest positions (483.87±1605.50 lux vs 490.75±1684.29 lux, p=1.00). Using a threshold of 1000 lux for outdoor exposure, the estimated light exposure at the eye-level position was significantly lower than that at the chest position (3.9% vs 7.8%, χ2=266.14, p<0.001) and the wrist position (3.9% vs 7.7%, χ2=254.25, p<0.001). CONCLUSIONS: Our findings revealed significant variations in light exposure among the wrist, chest and eye position. Therefore, caution must be exercised when comparing results obtained from different wearable devices.

Two-Dimensional Peripheral Refraction and Higher-Order Wavefront Aberrations Induced by Orthokeratology Lenses Decentration.

Purpose: The purpose of this study was to explore two-dimensional peripheral refraction and higher-order aberrations (HOAs) induced by orthokeratology lens decentration. Methods: Two-dimensional peripheral refraction and HOAs in a rectangular field (horizontally 60 degrees and vertically 36 degrees) were obtained using an open-view Hartmann-Shack wavefront sensor. The peripheral field was divided into 8 regions according to a combination of superior (UZ) or inferior (LZ) and a value, 1 (T25 to T30), 2 (T20 to T25), 3 (N20 to N25), or 4 (N25 to N30). The decentration of the lens was evaluated based on the change of power in the front of the tangential corneal map. All measurements were taken at the baseline and 1 month after lens fitting. Results: In total, 134 myopic children (age = 12.47 ± 1.70 years, SER = -2.44 ± 1.10 diopters [D]) were recruited. In general, horizontally asymmetrical change was observed in relative peripheral refraction (RPR), spherical aberration (SA), and horizontal coma. The root-mean square of higher order aberration (RMSHOA) and vertical coma demonstrated radial symmetrical change and vertically asymmetric change, respectively. Relative peripheral myopia was significantly increased after the treatment, with more myopic refraction in the temporal side. RPR changes in UZ2, UZ3, UZ4, LZ1, and LZ2 were related to the amount of lens decentration (r ≈ 0.4, P < 0.05). All HOAs increased after lens fitting (around 0.03 um, 0.02 um, 0.04 um, and 0.41 um for SA, horizontal COMA, vertical COMA, and RMSHOA in the periphery region). Conclusions: RPR and HOAs are related to lens decentration, which might contribute to the efficacy of orthokeratology. Translational Relevance: The study found a decentration-related optical feature after 1 month of lens wear, which is a suggested protective factor in myopia treatment. The findings might provide new insights for customized contact lens myopia treatment based on optics.

Characteristics of the Ocular Surface in Myopic Child Candidates of Orthokeratology Lens Wear.

INTRODUCTION: The purpose of this study was to investigate the characteristics of objective ocular surface parameters using non-invasive objective instruments in children with myopia who are candidates for orthokeratology lens wear. METHODS: Children with myopia who are candidates for orthokeratology lens wear were retrospectively investigated. The subjects were divided into three age groups. The Keratograph 5M and LipiView interferometry were used to assess non-invasive tear meniscus height (TMH), non-invasive tear film break-up time (NIBUT), conjunctival hyperemia redness score (RS), meibomian gland loss (MGL) score, lipid layer thickness (LLT), and blink pattern analysis, including the number of partial blinks (PB) and total blinks (TB), as well as the partial blink rate (PBR). RESULTS: A total of 1119 children with myopia (2070 eyes) aged 7-18 years were selected. The mean TMH, NIBUT, and LLT of the subjects was 0.21 mm, 12.45 s, and 65.28 nm, respectively. The mean RS and upper and lower MGL scores were 0.64, 1.00, and 1.06, respectively. The mean PB, TB, and PBR was 5.13, 6.46, and 0.81, respectively. Age was significantly correlated to all ocular surface parameters (p = 0.00), except for PB. NIBUT and LLT did not differ between male participants and female participants (all p > 0.05). TMH, RS, and upper and lower MGL were significantly higher in male participants than in female participants (all p < 0.01). In addition, NIBUT was positively associated with TMH (r = 0.13, p = 0.00) and LLT (r = 0.28, p = 0.00). Both upper and lower MGL were positively correlated with TMH, PB, and TB (all p = 0.00), whereas upper MGL was negatively correlated with NIBUT and LLT (all p < 0.05). TB was negatively correlated with NIBUT and LLT (all p = 0.00). PB had no relation with TMH, NIBUT, and LLT (all p > 0.05). In addition, PBR was positively correlated with NIBUT and LLT (all p = 0.00) but not with TMH, RS, or MGL (all p > 0.05). Overall, 57.00% had a TMH ≤ 0.2 mm, 43.20% had a NIBUT ≤ 10 s, 48.10% had an LLT ≤ 60 nm, and 88.10% had a PBR > 0.4. CONCLUSIONS: Child orthokeratology candidates have enhanced tear secretion and increased meibomian gland deficiency with aging. In addition, the adult dry eye diagnostic criteria may apply to orthokeratology candidates aged 12-18 years but should be lower for younger candidates. Given the proportion of abnormal risk, it is necessary to assess tear film status and blink pattern by reliable and feasible objective examination before fitting orthokeratology.

Two-step hierarchical neural network for classification of dry age-related macular degeneration using optical coherence tomography images.

Purpose: The aim of this study is to apply deep learning techniques for the development and validation of a system that categorizes various phases of dry age-related macular degeneration (AMD), including nascent geographic atrophy (nGA), through the analysis of optical coherence tomography (OCT) images. Methods: A total of 3,401 OCT macular images obtained from 338 patients admitted to Shenyang Aier Eye Hospital in 2019-2021 were collected for the development of the classification model. We adopted a convolutional neural network (CNN) model and introduced hierarchical structure along with image enhancement techniques to train a two-step CNN model to detect and classify normal and three phases of dry AMD: atrophy-associated drusen regression, nGA, and geographic atrophy (GA). Five-fold cross-validation was used to evaluate the performance of the multi-label classification model. Results: Experimental results obtained from five-fold cross-validation with different dry AMD classification models show that the proposed two-step hierarchical model with image enhancement achieves the best classification performance, with a f1-score of 91.32% and a kappa coefficients of 96.09% compared to the state-of-the-art models. The results obtained from the ablation study demonstrate that the proposed method not only improves accuracy across all categories in comparison to a traditional flat CNN model, but also substantially enhances the classification performance of nGA, with an improvement from 66.79 to 81.65%. Conclusion: This study introduces a novel two-step hierarchical deep learning approach in categorizing dry AMD progression phases, and demonstrates its efficacy. The high classification performance suggests its potential for guiding individualized treatment plans for patients with macular degeneration.

Intraocular complement activation is related to retinal vascular and neuronal degeneration in myopic retinopathy.

Purpose: To investigate the relationship between the intraocular levels of complement proteins and myopia-related retinal neuronal and vascular degeneration. Methods: Aqueous humour from 147 myopic patients, including 60 low-myopia and 87 high-myopia were collected during Implantable Collamer Lens implantation surgery. All participants received comprehensive ophthalmic examinations, including logMAR best corrected visual acuity, axial length measurement, fundus photography and ocular B-scan ultrasonography. The myopic eyes were further classified into simple myopia (SM, n = 78), myopic posterior staphyloma (PS, n = 39) and PS with myopic chorioretinal atrophy (PS + CA, n = 30). Retinal thickness and vascular density in the macula (6 mm × 6 mm) and optic nerve head (4.5 mm × 4.5 mm) were measured using Optical Coherence Tomography (OCT) and OCT angiography (OCTA). The levels of complement proteins including C1q, C3, C3b/iC3b, C4, CFB, CFH, C2, C4b, C5, C5a, CFD, MBL and CFI in the aqueous humour were measured using the Luminex Multiplexing system. The real-time RT-PCR was conducted to examine the expression of complement genes (C1q, C2, C3, C4, CFI and CFD) in the guinea pig model of long-term form deprivation-induced myopic retinal degeneration. Results: OCTA showed that retinal neuronal thickness and vascular density in superficial and deep layers of the macular zone as well as vascular density in the optic nerve head were progressively decreased from SM to PS and PS + CA (p < 0.05). The aqueous humour levels of C1q, C3, C3b/iC3b, C4, CFB, CFH, C2, C4b, C5 and CFI were significantly higher in high-myopic eyes compared to those in low-myopic eyes. Further subgroup analysis revealed the highest levels of complement components/fragments in the PS + CA group. The intraocular levels of complement factors particularly C3b/iC3b and C4 were negatively correlated with macular zone deep layer retinal thickness and vascular density and optic nerve head vascular density. The expression of C2, C3 and C4 genes was significantly higher in guinea pig eyes with myopic retinal degeneration compared to control eyes. Conclusions: The intraocular classical pathway and alternative pathway of the complement system are partially activated in pathological myopia. Their activation is related to the degeneration of retinal neurons and the vasculature in the macula and the vasculature in the optic nerve head.

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

PURPOSE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: Outdoor scene classrooms are appealing to teachers and students. Outcomes of the study will inform the efficacy of this strategy in Chinese children.

Short-term application of diquafosol ophthalmic solution benefits children with dry eye wearing orthokeratology lens.

Purpose: This aim of this study was to evaluate the effect of 3% Diquafosol Ophthalmic Solution (DQS) on children with dry eye from wearing overnight orthokeratology (OrthoK) lenses. Methods: Myopic children aged 8-18 years with dry eye syndrome were enrolled in this prospective observational study, and they were grouped according to their OrthoK treatment history for at least 1 year. All participants received DQS 4 times per day for 1 month. The following indicators were measured at baseline 1 month after treatment: the Dry Eye Questionnaire-5 (DEQ-5), non-invasive tear meniscus height (TMH), non-invasive tear film break-up time (first and average, NIBUT-F and NIBUT-A), meibomian gland score (MG score), conjunctival hyperemia redness score (R-scan), and blink pattern analysis. Results: A total of 104 participants (189 eyes) including 40 OrthoK wearers (72 eyes) and 64 Orthok candidates (117 eyes) completed the study. Of all, after DQS treatment for 1 month, DEQ-5 scores reduced from 5.54 ± 3.25 to 3.85 ± 2.98 (t = -3.36, p = 0.00). TMH increased from 0.20 ± 0.05 mm to 0.21 ± 0.05 mm (t = 2.59, p = 0.01), NIBUT-F and NIBUT-A were prolonged from 6.67 ± 4.71 s to 10.32 ± 6.19 s and from 8.86 ± 5.25 s to 13.30 ± 6.03 s (all p = 0.00), respectively. R-scan decreased from 0.69 ± 0.28 to 0.50 ± 0.25 (t = -9.01, p = 0.00). Upper MG scores decreased from 1.04 ± 0.32 to 0.97 ± 0.36 (t = -2.14, p = 0.03). Lower MG scores, partial blink rate, partial blinks, and total blinks did not change significantly. Both break-up time (BUT) and R-scan improved significantly after DQS treatment for 1 month (all p = 0.00) in OrthoK candidates and OrthoK wearers. Among the OrthoK wearers, TMH and dry eye symptoms increased significantly (all p = 0.00) but did not increase in OrthoK candidates (p > 0.05). There were no adverse events related to DQS. Conclusion: Diquafosol Ophthalmic Solution was effective for children wearing overnight orthokeratology in relieving dry eye symptoms and improving ocular surface parameters, which may help improve children's OrthoK wearing tolerance and compliance.

Two-dimensional peripheral refraction in adults.

Peripheral refraction has been studied for decades; however, its detection and description are somehow simplistic and limited. Therefore, their role in visual function and refractive correction, as well as myopia control, is not completely understood. This study aims to establish a database of two-dimensional (2D) peripheral refraction profiles in adults and explore the features for different central refraction values. A group of 479 adult subjects were recruited. Using an open-view Hartmann-Shack scanning wavefront sensor, their right naked eyes were measured. The overall features of the relative peripheral refraction maps showed myopic defocus, slight myopic defocus, and hyperopic defocus in the hyperopic and emmetropic groups, in the mild myopic group, and in other myopic groups, respectively. Defocus deviations with central refraction vary in different regions. The defocus asymmetry between the upper and lower retinas within 16° increased with the increase of central myopia. By characterizing the variation of peripheral defocus with central myopia, these results provide rich information for possible individual corrections and lens design.

Relative Myopic Defocus in the Superior Retina as an Indicator of Myopia Development in Children.

Purpose: To investigate the role of peripheral refraction in children's myopization. Methods: This 2-year study included 214 children (8-15 years old). Refraction across the retina (field of view: 60° × 36°) was measured with a custom-made aberrometer every year. Three datasets were established: dataset 1, 214 subjects from baseline to the first-year visit; dataset 2, 152 subjects from baseline to the second-year visit; and dataset 3, 59 initial emmetropes from baseline to the second-year visit. The baseline refraction of different retina regions was correlated with the central myopic shift, and was compared among groups with different levels of myopic shift. Results: In datasets 1 and 2, the refraction distribution across the retina was significantly different among the subjects who were initially emmetropes but not among those who were initially hyperopic or myopic. Refraction in the central vertical retina, especially in the superior retina (r = -0.5, P < 0.001), was significantly correlated with the myopic shift for emmetropes in that subjects with more relative myopia in the superior retina manifested greater central myopic shifts. In dataset 3, 21 subjects remained emmetropic after 2 years, 15 subjects became myopic at the 1-year visit, and 23 subjects became myopic at the 2-year visit. No difference was found for the relative peripheral refraction in all of the peripheral regions between the stage prior to and after the onset of myopia. Conclusions: Relative myopic defocus in the superior retina could be a predictor of central myopia shift. Changes in relative peripheral refraction are more likely a consequence of myopia progression rather than a cause.

Applied Forces Changed Myopia Lens Optical Performance but Not Retinal Image Quality Tested Using a Newly Designed Digital Colmascope.

Background: The aim of this study was to investigate the effects of applied forces generated by a rim screw on the optical performance of mounted myopia lenses. The residual refractive error and retinal image quality of the corrected eyes were also investigated. Methods: For 120 lenses, internal lens stress was measured using a newly designed digital strain viewer (colmascope). Sixty myopic adults (120 eyes) were recruited. The effects of internal lens stress on residual refraction and retinal image quality were evaluated using OPD Scan III. The results were compared between loose and tight mounting and between the right and left eyes. Results: Significant differences were observed among nine lens zones in both the right and left lenses, regardless of the mounting state (P < 0.001). The differences were mainly derived from the five vertically arranged zones (P < 0.05). Significant differences in internal lens stress were observed between the right and left lenses (P < 0.05). No significant differences in central residual refractive error and retinal image quality of the corrected eyes were found between the loose- and tight-mounted lenses. Conclusion: The applied forces generated by the rim screw changed the peripheral optical performance of the mounted myopia lenses but exerted only negligible impacts on the central residual refractive error and visual image quality.

GABAB Receptor Activation Affects Eye Growth in Chickens with Visually Induced Refractive Errors.

This study aims to explore the role of GABAB receptors in the development of deprivation myopia (DM), lens-induced myopia (LIM) and lens-induced hyperopia (LIH). Chicks were intravitreally injected with 25 µg baclofen (GABABR agonist) in one eye and saline into the fellow eye. Choroidal thickness (ChT) was measured via OCT before and 2, 4, 6, 8, 24 h after injection. ChT decreased strongly at 6 and 8 h after baclofen injection and returned back to baseline level after 24 h. Moreover, chicks were monocularly treated with translucent diffusers, -7D or +7D lenses and randomly assigned to baclofen or saline treatment. DM chicks were injected daily into both eyes, while LIM and LIH chicks were monocularly injected into the lens-wearing eyes, for 4 days. Refractive error, axial length and ChT were measured before and after treatment. Dopamine and its metabolites were analyzed via HPLC. Baclofen significantly reduced the myopic shift and eye growth in DM and LIM eyes. However, it did not change ChT compared to respective saline-injected eyes. On the other hand, baclofen inhibited the hyperopic shift and choroidal thickening in LIH eyes. All the baclofen-injected eyes showed significantly lower vitreal DOPAC content. Since GABA is an inhibitory ubiquitous neurotransmitter, interfering with its signaling affects spatial retinal processing and therefore refractive error development with both diffusers and lenses.

The Efficacy of Defocus Incorporated Multiple Segments Lenses in Slowing Myopia Progression: Results from Diverse Clinical Circumstances.

PURPOSE: Defocus incorporated multiple segments (DIMS) spectacle lenses were reported to slow myopia progression significantly in a randomized controlled trial (RCT). The study evaluated their effectiveness in clinical settings. DESIGN: Retrospective study. PARTICIPANTS: Patient records involving use of DIMS and single-vision (SV) spectacle lenses were collected from subsidiary hospitals of Aier Eye Hospital Group. METHODS: The spherical equivalent (SE), determined by subjective refraction, was adopted to assess the myopia progression. The strategy of propensity score matching (PSM) was applied to match the confounding baseline characteristics between the 2 groups. The effectiveness was calculated based on the difference of myopia progression of these 2 approaches. MAIN OUTCOME MEASURES: Change in SE. RESULTS: Three thousand six hundred thirty-nine patients with DIMS and 6838 patients with SV spectacles were included. The age of the patients was 6 to 16 years (mean ± standard deviation: 11.02 ± 2.53 years). The baseline SE was between 0.00 and -10.00 diopters (D) (mean ± standard deviation: -2.78 ± 1.74 D). After the PSM, data on 2240 pairs with 1-year follow-up and on 735 pairs with 2-year follow-up were obtained. Significantly slower progression was seen in the DIMS group at both the 1-year (DIMS, -0.50 ± 0.43 D; SV, -0.77 ± 0.58 D; P < 0.001) and 2-year (DIMS, -0.88 ± 0.62 D; SV, -1.23 ± 0.76 D; P < 0.001) subdataset. In the 1-year subdataset, 40% and 19% showed myopia progression of no more than 0.25 D for the DIMS and SV groups, respectively (chi-square, 223.43; P < 0.001), whereas 9% and 22% showed myopia progression of more than 1.00 D for the DIMS and SV groups, respectively (chi-square, 163.38; P < 0.001). In the 2-year subdataset, 33% and 20% showed myopia progression of no more than 0.50 D for the DIMS and SV groups, respectively (chi-square, 31.15; P < 0.001), whereas 12% and 29% showed myopia progression of more than 1.50 D for the DIMS and SV groups (chi-square, 65.60; P < 0.001). CONCLUSIONS: Although the magnitude was lower than that reported in the previous RCT, this large-scale study with diversity of the data sources confirmed the effectiveness of DIMS spectacles to slow myopia progression in clinical practice. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Two-Dimensional Peripheral Refraction and Image Quality for Four Types of Refractive Surgeries.

PURPOSE: To provide a comprehensive investigation of the optical quality across the visual field for current mainstream types of refractive surgeries. METHODS: Sixty eyes from 60 adults who received refractive surgery of either femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK), Q-value guided customized laser in situ keratomileusis (Q-LASIK), small incision lenticule extraction (SMILE), or Implantable Collamer Lens (ICL) (STAAR Surgical) implantation were included in this study. Refraction and optical aberrations from a visual field of horizontal 60° (from temporal 30° to nasal 30°) and vertical 36° (from superior 20° to inferior 16°) were measured using a custom-made Hartmann-Shack wavefront peripheral sensor. Refractive error, higher order aberrations, point spread function (PSF), and Strehl ratio were compared among these groups prior to and after the surgical procedures, respectively. RESULTS: All types of surgical procedures achieved an almost plano refraction in the central retina. This was also the case in the peripheral retina for the three types of laser refractive surgeries. However, residual peripheral relative hyperopic defocus was observed after ICL implantation. In all groups prior to the surgery, PSFs showed increasing distortion with eccentricity and arrow-like shape pointing toward the central fovea in the periphery in diagonals. Degradation of the PSFs was diminished by all three types of laser refractive surgeries, whereas ICL implantation made the peripheral distortion more prominent. CONCLUSIONS: Although ICL implantation produced a similar impact on refractive correction and objective optical quality in the central vision compared with other laser refractive surgeries, its outcome on the peripheral optics is different. The impact of this difference on visual performance deserves notice and warrants further investigation. [J Refract Surg. 2023;39(1):40-47.].

The Reliability and Acceptability of RDx-Based Tele-Controlled Subjective Refraction Compared with Traditional Subjective Refraction.

Purpose: The purpose of this study was to compare the reliability and acceptability of tele-controlled subjective refraction supported by RDx, a new technique that involves optical software designed for controlling phoropters remotely, to traditional subjective refraction. Methods: Sixty-five participants underwent tele-controlled subjective refraction and traditional subjective refraction randomly and nine of them underwent the second tele-controlled subjective refraction measurement on the same day. After their examinations, we distributed a validated satisfaction questionnaire to each participant. The elapsed time taken for refraction, sphere (S), cylinder (C), spherical equivalent (SE), vertical and oblique cylindrical vectors (J0 and J45), and best corrected visual acuity (BCVA) were compared. Age and refractive error type were included as covariates. Bland-Altman analysis was used to assess the agreement between both methods of refraction. Results: The mean age was 20.5 ± 5.9 years for all participants (aged 9 to 40 years); 57% were female participants. The repeatability analysis of tele-controlled method showed no significant differences for all parameters (P > 0.05). We found no statistical differences (P > 0.05) between tele-controlled subjective refraction and traditional subjective refraction for all parameters in either group. The mean difference and 95% limits of agreement for SE, J0, and J45 were -0.03 ± 0.36 diopters (D), -0.00 ± 0.57 D, and -0.01 ± 0.79 D, respectively. The tele-controlled method took more time to perform than the traditional one (P < 0.05). Completed questionnaires were returned by 55 participants (85%), and they showed high satisfaction and acceptance of the tele-controlled method (98%). Conclusions: Tele-controlled subjective refraction results agreed with traditional subjective refraction for all refraction components except for cylinder vectors. In addition, the broad acceptability of tele-controlled subjective refraction means practicability in clinical practice. Translation Relevance: The RDx-based tele-controlled method can provide an alternative to subjective refraction, especially in areas that lack experienced optometrists.

Efficacy of contact lenses for myopia control: Insights from a randomised, contralateral study design.

PURPOSE: To determine the efficacy of two myopia control contact lenses (CL) compared with a single-vision (SV) CL. METHODS: Ninety-five Chinese children with myopia, aged 7-13 years in a 1-year prospective, randomised, contralateral, cross-over clinical trial with 3 groups; bilateral SVCL (Group I); randomised, contralateral wear of an extended depth of focus (EDOF) CL and SVCL (Group II) and MiSight® CL and SVCL (Group III). In Groups II and III, CL were crossed over at the 6-month point (Stage 1) and worn for a further 6 months (Stage 2). Group I wore SVCL during both stages. At baseline and the end of each stage, cycloplegic spherical equivalent refractive error (SE) and axial length (AL) were measured. Six-monthly ΔSE/ΔAL across groups was analysed using a linear mixed model (CL type, stage, eye and eye* stage included as factors). Intra-group paired differences between eyes were determined. RESULTS: In Group I, mean (SD) ΔSE/ΔAL with SVCL was -0.41 (0.28) D/0.13 (0.09) mm and -0.25 (0.27) D/0.16 (0.09) mm for stages 1 and 2, with a mean paired difference between eyes of 0.01 D/0.01 mm and 0.05 D/-0.01 mm, respectively. ΔSE/ΔAL with SVCL was similar across Groups I to III (Stage 1: p = 0.89/0.44, Stage 2: p = 0.70/ 0.64). In Groups II and III, ΔSE/ΔAL was lower with the EDOF and MiSight® CL than the contralateral SVCL in 68% to 94% of participants, and adjusted 6-month ΔSE/ΔAL with EDOF was similar to MiSight® (p = 0.49/0.56 for ΔSE/ΔAL, respectively). Discontinuations across the three groups were high, but not different between the groups (33.3%, 48.4% and 50% for Groups I to III, respectively [p = 0.19]) and most discontinuations occurred immediately after baseline. CONCLUSIONS: Extended depth of focus and MiSight® CL demonstrated similar efficacy in slowing myopia. When switched from a myopia control CL to SVCL, myopia progression was similar to that observed with age-matched wearers in SVCL and not suggestive of rebound.