Comparing Myopia Control Efficacy and Corneal Power Changes in Children wearing Corneal Refractive Therapy (CRT) and Vision Shaping Treatment (VST) Orthokeratology Lenses with Smaller Back Optic Zone Diameters.

Fitting efficacy and ocular surface safety of digitally customized orthokeratology lenses in patients with moderate myopia and high curvature corneas.

Orthokeratology (OK) lenses for myopia correction are susceptible to biofouling by tear-derived biomolecules, escalating the risks of ocular infection and inflammation. Prevailing studies that rely on end point protein quantification fail to capture the real-time kinetics of fouling formation. Here, we fabricated a UV pressure-assisted polymer-grafted quartz crystal microbalance with dissipation monitoring (QCM-D) sensor exhibiting exceptional stability, nanoscale smoothness (RMS roughness ≈2 nm), and interfacial peel resistance. This platform enables in situ tracking of adsorption/desorption kinetics for four critical tear components: native/denatured lysozyme and oxidized/native lecithin. Key findings reveal a flow-dependent fouling behavior, wherein low flow rates increase biomolecule adsorption by 37-80% compared with higher flows. We further identify denatured lysozyme and native lecithin as resilient contaminants characterized by a stronger deposition affinity and pronounced resistance to elution. Quantitative screening of multipurpose solutions (MPSs) demonstrates that MPS #2 achieves 20-100% elution rate across biomolecules, outperforming commercial benchmarks. By leveraging dissipation-frequency (D-F) analysis, we clarify the fundamental mechanisms of biofouling formation at the molecular level. Collectively, this work establishes three critical advances: (1) a real-time biofouling diagnostic platform for OK lens interfaces, (2) molecular design principles for antifouling materials based on adhesion remodeling theory, and (3) an accelerated MPS formulation screening paradigm for ocular device safety.

Orthokeratology (OK) has been recognized as an effective intervention for slowing myopia progression. However, its effects on the accommodative response and its role in myopia control remain controversial. This systematic review and meta-analysis aimed to provide a comprehensive evaluation of the OK influence on accommodation. Cochrane, Embase, and PubMed were searched for studies published up to April, 2024. All eligible studies that compared OK with a neutral control and reported measurements related to accommodative response in myopic patients were included. The outcomes evaluated were accommodation lag (AL), positive relative accommodation, and accommodation amplitude (AA). The mean difference [MD] and 95% confidence interval were used for continuous outcomes. Heterogeneity was assessed using I2 statistics. The analysis was performed using R software version 4.4.1. A total of 14 studies comprising 1,404 patients met the inclusion criteria. Single vision spectacles was the control group in 12 articles, soft single vision contact lenses in one, and no intervention in one. The OK group showed a significant reduction in AL compared with control groups at 3 months follow-up (MD: -0.38D; confidence interval [CI]: -0.54 to -0.22D; P<0.00001; I2=0%). At 12 months, OK significantly increased AA compared with controls (MD: 0.64D; CI: 0.25 to 1.03D; P=0.001; I2=69%), which was not observed at 3 months (MD: 0.26D; CI: -0.16 to 0.70D; P=0.21; I2=80%). Positive relative accommodation did not differ significantly at 3 months (MD: -0.53D; CI: -1.08 to 0.02D; P=0.06; I2=83%). This meta-analysis demonstrates that OK significantly reduces AL and, in the long-term, increases AA compared with controls. These findings suggest that OK does improve the accommodation response, which may contribute to one of the mechanisms underlying its effectiveness in slowing myopia progression.

ABSTRACT Clinical relevance The safety of orthokeratology needs to be regularly monitored. Retrospective studies of orthokeratology can provide safety data for real-world clinical settings. Background This study aimed to evaluate the safety of an orthokeratology lens (Paragon CRT® 100 and Paragon CRT® Dual Axis [CRT-E], Paragon Vision Sciences, Inc. a CooperVision company; paflufocon D) among myopic Chinese children and adults. Methods Patient records were reviewed for ocular adverse events at five clinical sites in China. Patient records meeting all of the following criteria were selected for data extraction: sphere refraction within −4.00 D (inclusive) and astigmatism within 1.50 D (inclusive) before wearing corneal refractive therapy (CRT) lenses, and wear of CRT lenses for over 335 days. Ocular adverse events are reported, by person, as number of events, incidence, and incidence rate. Results In total, 2,793 patient records were screened, and 2,768 met the data-extraction criteria. Patients were aged 6 to 33 years; median age was 10 years (IQR: 9–12 years). Most patients (2,318) wore CRT lenses in both eyes, although 450 patients had monocular treatment. Lens wear totalled 3,269 patient-years, during which there were no serious ocular adverse events. There were 300 ocular adverse events among 241 patients (incidence of 8.7%); 282 events were mild, and 18 events were moderate. Device-related ocular adverse events occurred 175 times among 134 patients (4.8% incidence); 167 events were mild, and 8 events were moderate. The most common device-related events were corneal epithelial defects (108) – including corneal epithelial staining, abrasion, and epithelial roughness – and conjunctival hyperaemia (23), most of which self-resolved. The rate of device-related ocular adverse events was 5.4 per 100 patient-years (95% CI: 4.6–6.2). Conclusion The orthokeratology lenses are safe for overnight wear among Chinese myopes, as demonstrated by the low incidence and mild-to-moderate nature of ocular adverse events.

Orthokeratology (OK) has been widely adopted as a non-surgical intervention to slow myopia progression in children and adolescents. In China, where myopia prevalence is exceptionally high, OK lenses are commonly prescribed to school-aged children as an early intervention strategy. As these individuals reach adulthood, many pursue permanent refractive correction-such as small-incision lenticule extraction (SMILE)-to meet unaided visual acuity standards required for university entrance, military service, or certain occupations. However, the long-term morphological effects of OK wear and their potential impact on SMILE outcomes remain inadequately understood. This study aimed to evaluate ocular biometric and corneal morphological changes following long-term OK lens discontinuation and to compare the visual and surgical outcomes of SMILE between former OK users and spectacle-wearing controls. This retrospective comparative study included 44 myopic eyes-22 from patients with a history of OK lens wear (average duration: 64.8 ± 22.6 months; discontinuation ≥ 3 months) and 22 from age- and refractive error-matched controls. Examinations were conducted pre-OK (baseline), pre-SMILE, and at 1 month, 6 months, and final follow-up. Parameters included uncorrected and corrected distance visual acuity (UDVA, CDVA), corneal topography, pachymetry, volume, curvature, and higher-order aberrations. Astigmatic outcomes were evaluated using Alpins vector analysis. After OK discontinuation, the OK group exhibited increased corneal astigmatism (P = 0.030), spherical aberration (P = 0.036), and total aberrations (P = 0.034), as well as decreased vertical coma (P = 0.004), central corneal thickness (P < 0.001), and corneal volume (P = 0.001). Posterior corneal curvature steepened significantly (P < 0.001), while anterior curvature remained stable. Further correlation analysis showed that a younger age at initial OK lens wear was significantly associated with greater posterior steepening after discontinuation at the 3mm, 5mm, and 7mm zones (all P < 0.050). There was also a borderline negative correlation between the duration of OK lens wear and changes in posterior steep K value, suggesting longer wear may result in more pronounced steepening. At 6 months and final follow-up, both groups demonstrated comparable UDVA, CDVA, corneal shape, and higher-order aberrations (all P > 0.050). Vector analysis revealed no significant group differences in astigmatic correction. SMILE remains a viable option for former OK users; the observed reduction in CCT after lens discontinuation has minimal impact on refractive surgery selection.

To establish and validate short-term and long-term prediction models for the therapeutic outcomes of orthokeratology (OK) lenses in children, incorporating baseline ocular parameters and dynamic changes in axial length (AL) as predictive variables. This retrospective cohort study included 896 pediatric patients who underwent OK lenses treatment at Tianjin Medical University Eye Hospital from January 2020 to July 2025, with a minimum follow-up period of one year. Baseline demographic and ocular parameters were collected, and AL changes were introduced as dynamic predictors in models starting from year two. Seven machine learning algorithms were used to construct prediction models, including LightGBM, random forest, support vector machine (SVM), and artificial neural network (ANN). Model performance was evaluated using the area under the receiver operating characteristic curve (AUC), F1 score, sensitivity, specificity, calibration, and decision curve analyses. Model interpretability was explored using SHAP and LIME analyses. Among the 896 included children, 566 achieved reasonable AL control, and 330 showed poor control during the first year. Baseline AL, corneal eccentricity parameters, and refractive error were significantly associated with treatment outcomes. The optimal second-year prediction model (LightGBM) achieved an area under the receiver operating characteristic curve (AUC) of 0.96 with an F1 score of 0.86. For long-term prediction, the SVM model demonstrated moderate and stable performance, with F1 scores of 0.73 and 0.75 in the third- and fourth-year models, respectively. Prediction models based on baseline parameters and dynamic AL changes can effectively estimate both short-term and long-term efficacy of OK treatment in children. Dynamic AL change in the first year is a robust predictor of long-term outcomes, offering potential for individualized myopia management strategies.

Effects of wearing orthokeratology lenses for more than 5years on the ocular surface of adolescents.

The change of regional relative peripheral refraction after orthokeratology and its correlation with corneal reshaping parameters.

Impact of orthokeratology lens decentration on axial length growth in Chinese myopic children: A meta-analysis.

The relationship between relative peripheral refraction and axial length elongation in myopic children wearing orthokeratology lenses using a novel wide-angle multispectral refraction topographer.

PurposeTo evaluate the efficacy and safety of combining repeated low-level red light (RLRL) therapy with orthokeratology (OK) in slowing axial elongation in children with rapid myopia progression.Patients and MethodsThis retrospective cohort included 72 children aged 8–14 years (RLRL+OK, n=36; OK-only, n=36) meeting the rapid-progressor definition (>0.40 mm/year axial elongation. One eye per child was randomly selected. Axial length (AL) was measured at baseline and at 3, 6, and 12 months. Inverse probability of treatment weighting (IPTW) based on age, sex, and baseline AL achieved good balance between groups. The primary outcome was the 12-month AL change, assessed using IPTW-weighted linear mixed-effects models adjusted for covariates. Prespecified subgroup analyses were stratified by age (<10 vs ≥10 years). Sensitivity analyses included propensity score matching (PSM), per-protocol analysis (PP; adherence ≥80%), and dose–response evaluation. Safety was assessed using slit-lamp biomicroscopy and macular OCT imaging.ResultsAt 12 months, the RLRL+OK group had significantly less elongation than OK-only (mean difference −0.298 mm; 95% CI −0.388 to −0.209; p<0.001), with significant group×time interactions from 3 months. Benefits were consistent across age subgroups without effect modification. Sensitivity analyses confirmed robustness: PSM (−0.255 mm; p<0.001) and PP (−0.298 mm; p<0.001). Dose–response showed each 10% higher adherence reduced elongation by −0.148 mm (p<0.001). No clinically significant adverse events were detected.ConclusionRLRL combined with OK significantly reduced axial elongation in rapid-progressing children compared with OK alone, with a clear adherence-dependent effect and reassuring short-term safety profile.

To compare the effect of orthokeratology (OK) and defocus incorporated multiple segment (DIMS) lenses on axial length (AL) elongation in bilateral myopic anisometropic children. This retrospective study enrolled bilateral myopic anisometropic children categorized into two groups: OK lenses and DIMS lenses. The eyes with more myopia (MM) were divided into MM eyes and the fellow eyes with less myopia (LM) into LM eyes. According to the myopia degree in MM eyes, the subjects were further assigned to -0.50 to -3.00 D subgroup and -3.25 to -6.00 D subgroup. The t-test was used to analyze the changes in AL elongation between groups and AL differences in both eyes, and the relationship between AL changes and baseline data was evaluated by Pearson linear correlation analysis. Totally 202 children (8-14y) were divided into OK group with mean age 10.97±1.91y (46 males and 50 females) and DIMS group with mean age 11.05±2.06y (58 males and 48 females). After 1y, the changes of AL in OK-MM eyes (0.14±0.18 mm) were significantly slower than that in OK-LM eyes (0.20±0.19 mm) and DIMS-MM eyes (0.19±0.18; P<0.001, P=0.037). The OK-LM eyes and DIMS-LM eyes, DIMS-MM eyes and DIMS-LM eyes showed no statistically significant difference in AL changes (P=0.337, 0.381). In the -0.50 to -3.00 D subgroups, DIMS-LM eyes had better effect of AL control than OK-LM eyes, the changes of AL in OK-MM eyes and DIMS-MM eyes were no statistically significant. In the -3.25 to -6.00 D subgroups, the results were similar in total group. The change of AL in four subgroups was negatively correlated with age (P<0.05). OK lens can reduce binocular anisometropia; DIMS lens has similar effect on the control of binocular myopia in children with myopic anisometropia. The OK lenses are more effective than DIMS lenses with higher degrees of myopia, while DIMS lens retard AL elongation more effectively than OK lens when the spherical equivalent refraction of MM eyes is lower than -3.00 D.

To investigate and compare seasonal variations in axial length (AL) in myopic children with defocus incorporated multiple segments (DIMS) spectacle lenses combined with 0.01% atropine (DIMSA) and orthokeratology (OK) lenses. The present retrospective study involved 428 subjects, mean age 9.70 ± 1.94 years, categorized into two groups: DIMSA (203 cases), and OK lenses (225 cases). Data were classified as "summer" or "winter" based on the midpoint of the 6 months between visits. Initial clinical visit (baseline) and one-year follow-up data were collected, and only data from the right eye was retrieved for analysis. Axial elongation over time and between groups was analyzed. The mean change in AL at 1 year was 0.18 ± 0.19 mm in the DIMSA group and 0.19 ± 0.15 mm in the OK group, with no significance between the two groups (p>0.05). In both groups, the change of AL in winter was significantly higher than that in summer (P<0.01). A similar seasonal pattern was found among children 7-8 years of age in the DIMSA group and 7-12 years of age in the OK group, as well as for those with an initial AL < 26 mm. DIMSA and OK lenses show similar reductions in myopia progression at different times of the year. Axial elongation decreased in summer, and this phenomenon disappears with increasing age and AL.

To evaluate the efficacy of visual training (VT) in retarding axial elongation in myopic children and to determine its additive clinical value when combined with standard myopia control modalities, including orthokeratology (OK), defocus spectacles (DS), and low-concentration atropine (LCA). This is a retrospective, multicenter, self-controlled cohort study. A total of 208 myopic children (mean age 9.73 ± 2.08 years) who underwent a structured visual training program were included. Subjects were stratified into five subgroups based on concurrent treatments: VT monotherapy, VT+DS, VT+OK, VT+DS+LCA, and VT+OK+LCA. Annualized axial elongation rates were calculated for the pre-training (baseline) and post-training intervals. The primary outcome was the reduction in axial elongation rate. The mean axial elongation rate significantly attenuated from a baseline of 0.38 ± 0.34 mm/year to 0.23 ± 0.30 mm/year following the intervention (P < 0.001), representing a mean reduction of 0.15 ± 0.31 mm/year. There were no statistically significant differences in the magnitude of rate reduction among the five subgroups (P = 0.826), indicating that VT confers a consistent additive benefit independent of concurrent optical or pharmacological therapies. Pearson correlation analysis revealed a good positive association between baseline progression rate and treatment efficacy (r = 0.57, P < 0.001), suggesting that children with faster initial progression derived the greatest therapeutic benefit. Visual training effectively slows axial elongation, shifting pathological growth trajectories toward physiological norms. It functions as a universal adjunctive therapy, providing robust and independent protective effects regardless of whether the patient is using OK lenses, defocus spectacles, or atropine. These findings support the use of visual training as a priority "rescue therapy" for rapid progressors.

Objective.This study aimed to automate the extraction of local corneal topography (CT) features in myopic children undergoing orthokeratology (OK), evaluate their causal effects on axial length (AL) control, and develop a predictive model for AL progression.Approach.We retrospectively analyzed myopic children who had received OK treatment for more than 12 months. Advanced digital image processing techniques were employed to automatically quantify three critical CT parameters: treatment zone area (TZA), eccentric distance (ED), and eccentric angle (EA). Counterfactual inference quantified causal relationships between these parameters and AL changes. Baseline characteristics and one-month CT features were used to train a CatBoost prediction model.Main results.This study included 143 myopic subjects (276 eyes) treated with OK lenses. The image processing algorithm performed comparably to manual annotation, with mean absolute percentage errors of 2.1% (TZA), 1.2% (ED), and 0.7% (EA). Per unit increase, TZA, ED, and EA were associated with AL changes of 0.054 mm, -0.161 mm, and -0.0003 mm, respectively. The CatBoost model, using initial AL and age, predicted six-month and one-year AL with absolute errors of 0.180 and 0.169 mm.Significance.This work establishes an integrated artificial intelligence (AI) framework that combines automated CT analysis, causal inference, and predictive modeling. It provides clinicians with an interpretable tool for assessing OK efficacy and forecasting myopia progression, while paving the way for next-generation healthcare AI systems with integrated perceptual, explanatory, and prognostic capabilities.

Myopia is a global health concern, with an increasing prevalence in pediatric populations. Orthokeratology (OK) lenses have been explored as a non-invasive intervention that may slow axial elongation and improve refractive outcomes in children with myopia, potentially through peripheral retinal defocus remodeling. The present prospective cohort study evaluated the impact of OK lens wear on axial length, refractive error and visual parameters in myopic children over a 3-year period. A total of 188 myopic children <18 years of age (100 males; 88 females; mean age, 12.5±2.1 years), with baseline spherical equivalent refractive errors ranging from -1.00 to -6.00 D were enrolled. Participants were fitted with OK lenses and monitored at 1 week, 1 month and every 3 months thereafter to monitor compliance, assess lens fit and address any adverse events. Axial length increased from 24.12±0.63 mm at baseline to 24.70±0.12 mm over 36 months (mean elongation, 0.58 mm; P<0.01). Refractive error improved from -3.25±1.05 to -2.82±0.18 D (mean change, +0.43 D; P<0.01). Patient compliance levels were categorized according to adherence and adverse effects: High (n=120), moderate (n=50) and low (n=18). Compliance significantly influenced outcomes, with highly compliant participants having a lower mean axial elongation (0.35±0.07 mm) compared with that of participants with the lowest compliance (0.72±0.12 mm; P<0.01). Adverse events were infrequent, including corneal staining (n=15; 8.0%), lens intolerance (n=10; 5.3%) and conjunctival redness (n=20; 10.6%). The mean resolution time of these adverse effects ranged from 3.2 to 6.0 days. These findings indicate that OK lenses significantly improved refractive error and visual acuity in children with myopia. Compliance was identified as a critical factor influencing treatment efficacy. Therefore, it is suggested that OK should be considered an integral component of moderate myopia management protocols for pediatric patients.

Myopia is a growing health concern, especially among children, with Orthokeratology (OK) lenses showing promising results in myopia control. However, treatment outcomes vary significantly among individuals, highlighting the need for personalized approaches. This study aimed to develop and validate a predictive model for OK therapy outcomes in myopic children. This retrospective cohort study included 439 myopic patients fitted with OK lenses. Patients were randomly divided into training (n = 308) and test (n = 131) sets. Least absolute shrinkage and selection operator regression was used for variable selection, followed by logistic regression to construct the predictive model. A nomogram was developed to visualize individual risk predictions. Model performance was assessed using calibration plots, receiver operating characteristic (ROC) curves, and decision curve analysis (DCA). Four variables were identified as significant predictors: age, parental myopia, white-to-white distance, and spherical refraction. The model demonstrated good discriminatory ability with areas under the ROC curve of 0.831 (95% CI: 0.786-0.877) in the training set and 0.820 (95% CI: 0.742-0.899) in the test set. Sensitivity and specificity were 75.6 and 72.8% in the training set, and 79.3 and 75.0% in the test set. Calibration plots and DCA confirmed the model's potential clinical utility across a range of threshold probabilities. This study developed a predictive model for OK therapy outcomes in myopic children. The model demonstrated good discriminatory ability in both training and test datasets. This predictive approach might contribute to risk stratification in myopia management. Further validation through prospective studies across diverse populations is needed before such models could potentially inform clinical decision-making and resource allocation in myopia control practice.

ABSTRACT Purpose To evaluate the efficacy and safety of repeated low-level red-light (RLRL) therapy in combination with orthokeratology (OK) for controlling myopia in Spanish children. Methods A single-site, randomized, parallel-group, single-blinded clinical trial. Twenty-six children aged 8–15 years with myopia between −0.75 to −6.75 D were enrolled. Participants were randomly assigned to either the RLRL combined with OK (RCO) group (n = 11) or the OK-only group (n = 15). The OK group wore OK lenses for at least 8 hours per night, while the RCO group received additional daily RLRL therapy, administered twice daily for 3 minutes per session five days per week. Follow-up visits were conducted at 1, 3, 6, and 12 months, with compliance and safety monitoring. The primary outcome measure was axial length (AL) change. Results All 26 children completed the 6-month follow-up visit. After 6 months, the adjusted mean AL change was −0.057 mm (95% CI, −0.078 to −0.037 mm) in RCO group, and 0.041 mm (95% CI, 0.029 to 0.054 mm) in OK group. In RCO group, 5 children (45.5%) achieved clinically significant axial shortening (defined as AL change ≤ −0.05 mm). The adjusted mean macular thickness change was 0.664 µm (95% CI, 0.468 to 0.859 µm) in RCO group, and 0.077 µm (95% CI, −0.048 to 0.203 µm) in OK group. No severe adverse events or significant corneal findings were observed. Conclusions The six-month interim analysis indicates that combining RLRL therapy with OK effectively controls myopia progression in Spanish children, with no severe adverse effects. Long-term follow-up is ongoing.

PurposeMyopia represents the most prevalent ocular condition among children and adolescents worldwide, exhibiting marked variations in prevalence across regions and ethnic groups. This study aimed to assess and compare the effectiveness and safety of two orthokeratology (OK) lens types—corneal refractive therapy (CRT) and vision shaping treatment (VST)—for controlling myopia progression across different age groups.MethodsA retrospective cohort analysis was performed on 105 pediatric patients (210 eyes; aged 8–16 years) clinically diagnosed with myopia who wore CRT or VST lenses for at least 12 months. Longitudinal evaluations included axial length (AL) progression, axial length-to-corneal curvature (AL/CR) ratio, corneal curvature, corneal eccentricity indices (e-values), and safety parameters.ResultsCRT lenses markedly limited AL elongation and reduced corneal curvature flattening in participants younger than 13 years (p < 0.0001), whereas VST lenses produced more favorable changes in E-values among those older than 11 years (p < 0.05). No significant difference was observed between the groups in the AL/CR ratio control (p > 0.05). Both lens designs maintained similar safety outcomes, with only mild corneal epithelial staining detected across all groups.ConclusionThe results reveal age-dependent variations in effectiveness, supporting an individualized approach to OK lens selection for optimized myopia management.