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Purpose: Using deep learning model to observe the blinking characteristics and evaluate the changes and their correlation with tear film characteristics in children with long-term use of orthokeratology (ortho-K). Methods: 31 children (58 eyes) who had used ortho-K for more than 1 year and 31 age and gender-matched controls were selected for follow-up in our ophthalmology clinic from 2021/09 to 2023/10 in this retrospective case-control study. Both groups underwent comprehensive ophthalmological examinations, including Ocular Surface Disease Index (OSDI) scoring, Keratograph 5M, and LipiView. A deep learning system based on U-Net and Swim-Transformer was proposed for the observation of blinking characteristics. The frequency of incomplete blinks (IB), complete blinks (CB) and incomplete blinking rate (IBR) within 20 s, as well as the duration of the closing, closed, and opening phases in the blink wave were calculated by our deep learning system. Relative IPH% was proposed and defined as the ratio of the mean of IPH% within 20 s to the maximum value of IPH% to indicate the extent of incomplete blinking. Furthermore, the accuracy, precision, sensitivity, specificity, F1 score of the overall U-Net-Swin-Transformer model, and its consistency with built-in algorithm were evaluated as well. Independent t-test and Mann-Whitney test was used to analyze the blinking patterns and tear film characteristics between the long-term ortho-K wearer group and the control group. Spearman's rank correlation was used to analyze the relationship between blinking patterns and tear film stability. Results: Our deep learning system demonstrated high performance (accuracy = 98.13%, precision = 96.46%, sensitivity = 98.10%, specificity = 98.10%, F1 score = 0.9727) in the observation of blinking patterns. The OSDI scores, conjunctival redness, lipid layer thickness (LLT), and tear meniscus height did not change significantly between two groups. Notably, the ortho-K group exhibited shorter first (11.75 ± 7.42 s vs. 14.87 ± 7.93 s, p = 0.030) and average non-invasive tear break-up times (NIBUT) (13.67 ± 7.0 s vs. 16.60 ± 7.24 s, p = 0.029) compared to the control group. They demonstrated a higher IB (4.26 ± 2.98 vs. 2.36 ± 2.55, p < 0.001), IBR (0.81 ± 0.28 vs. 0.46 ± 0.39, p < 0.001), relative IPH% (0.3229 ± 0.1539 vs. 0.2233 ± 0.1960, p = 0.004) and prolonged eye-closing phase (0.18 ± 0.08 s vs. 0.15 ± 0.07 s, p = 0.032) and opening phase (0.35 ± 0.12 s vs. 0.28 ± 0.14 s, p = 0.015) compared to controls. In addition, Spearman's correlation analysis revealed a negative correlation between incomplete blinks and NIBUT (for first-NIBUT, r = −0.292, p = 0.004; for avg-NIBUT, r = −0.3512, p < 0.001) in children with long-term use of ortho-K. Conclusion: The deep learning system based on U-net and Swim-Transformer achieved optimal performance in the observation of blinking characteristics. Children with long-term use of ortho-K presented an increase in the frequency and rate of incomplete blinks and prolonged eye closing phase and opening phase. The increased frequency of incomplete blinks was associated with decreased tear film stability, indicating the importance of monitoring children's blinking patterns as well as tear film status in clinical follow-up. [ABSTRACT FROM AUTHOR]

Background: This study aimed to assess the effect of peripheral defocus with orthokeratology lenses (PDOK) on myopia control in children and adolescents through a systematic review and meta-analysis. Methods: A comprehensive search was conducted in the PubMed and Web of Science databases to identify randomized controlled trials (RCTs) and cohort studies on PDOK, using the keywords "peripheral refraction" and "orthokeratology". Studies were included if they reported spherical equivalent (M) peripheral refraction at 25° and/or 30° with accompanying statistical data along the horizontal meridian before and after orthokeratology treatment. From the initial 133 studies, those excluded included nine non-English publications, 18 reviews, five meta-analyses, four systematic reviews, and 88 studies not meeting the inclusion criteria. Results: Nine studies (three RCTs and six cohort studies) were included, involving 259 participants aged six to 30 years with a baseline refractive error of M = −2.44 ± 0.27 D, and treatment duration ranging from 14 days to 12 months. All the studies showed an increase in myopic defocus at 30° nasal (−2.55 ± 1.10 D) and temporal (−2.79 ± 0.75 D) eccentricities, averaging −2.67 ± 0.95 D across both. The overall induced myopic defocus was M = −2.56 D (95% CI: −2.21 to −2.91, Z = 14.33, p < 0.001), according to forest plot analysis. Studies with treatment durations up to one year showed a higher myopic blur (M = −2.69 D, 95% CI: −2.48 to −2.89, Z = 25.93, p < 0.001) compared to shorter treatments of less than three months (M = −2.39 D, 95% CI: −1.76 to −3.02, Z = 7.41, p < 0.001). Conclusions: Orthokeratology lenses effectively induce myopic defocus at 30° eccentricity over both short- and long-term treatments in children and adolescents, suggesting potential benefits for myopia control in these age groups. [ABSTRACT FROM AUTHOR]

Purpose: To discuss the characteristics of anterior corneal elevation asymmetry in myopic eyes and clarify which kind of asymmetry most influenced lens position. Methods: In this retrospective study of 199 consecutive myopic participants, corneal topography was used to analyse asymmetry in anterior corneal elevation. Amongst them, 65 participants (65 eyes) who underwent orthokeratology (31 and 34 with spherical and toric lenses, respectively) were re‐evaluated. Stepwise multiple linear regression analysis was used to identify the contributing factors that influenced lens decentration. Receiver operating characteristic curve (ROC) analysis was employed to assess how the corneal asymmetry vector could predict decentration. Results: There were no significant differences in treatment zone decentration (TZDec) between participants wearing toric and spherical lenses (p = 0.60 and 0.64 for 1 week and 1 month of wear, respectively). Amongst the underlying factors, the magnitude of TZDec was only correlated with the amount of corneal asymmetry vector (standardised β = 0.44, 0.48, p < 0.001 for all) after 1 week and 1 month of wear, and the direction of TZDec after 1 month of lens wear was associated with the angle of the asymmetry vector (r = 0.25, p = 0.04). ROC analysis showed that the magnitude of corneal asymmetry vector produced accurate discrimination between non‐severe and severe decentration for 1 week and 1 month of wear (area under the curve was 0.93 ± 0.04 and 0.89 ± 0.05, respectively, p < 0.001). Amongst participants whose corneal asymmetry vector exceeded 41.06 μm and was oriented inferiorly, 35.29% showed severe decentration after 1 month of lens wear. Conclusions: In myopic participants, corneal asymmetry existed in the 8.0 mm chord diameter. If the asymmetry vector >41.06 μm and the direction was oriented inferiorly, then practitioners must be vigilant about severe decentration which would not be alleviated by a toric design. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the incidence of microbial keratitis among Japanese patients wearing orthokeratology (ortho-k) lenses Study design: Retrospective multicenter study Method: This study was conducted at 4 hospitals in Japan and involved 1438 patients who had been prescribed ortho-k lenses and had worn them for at least 3 months. Data on patient demographics, lens characteristics, lens care systems, and presence of microbial keratitis were extracted from the medical records. Duration of ortho-k lens wear was calculated from the original fitting date to the patient's last visit, with the total years of lens wear used as person-years of lens wear. The incidence of microbial keratitis was calculated by dividing the number of infected cases by the total person-years of lens wear for all enrolled participants. Results: Among the 1438 patients, 753 were male and 685 were female, with a mean age of 12.7 ± 5.4 years. The mean duration of ortho-k lens wear was 5.2 ± 4.5 years, and the mean lens power was -3.52 ± 1.41 D. The total person-years of lens wear for all enrolled patients was 7415. Four cases of microbial keratitis were identified, resulting in an overall incidence of microbial keratitis of 5.4 (95% CI: 1.0–9.8) per 10,000 patient-years among ortho-k lens wearers. Conclusion: This study represents the largest sample size to date for estimating the incidence of microbial keratitis associated with ortho-k lenses. The incidence was similar to or slightly lower than that of previous studies on ortho-k-related microbial keratitis and also comparable to that of daily wear soft contact lenses. [ABSTRACT FROM AUTHOR]

Myopia, an increasingly grave public health concern, necessitates the implementation of various techniques for its management. These techniques predominantly comprise the employment of spectacles correction, orthokeratology (ortho-k), and soft bifocal and multifocal lenses. In the present study, a pioneering polish-free ortho-k lens was devised, featuring two reverse lines and three alignment lines, which, respectively, expedite the shaping process and enhance centration. The structural blueprint of the ortho-k lens, along with the simulation of fluorescence staining, was executed employing the FocalPoints software V7.0 (Advance Medical, Milan, Italy). Subsequently, lens aberration elimination was accomplished through ray tracing utilizing ZEMAX software V13.0 (Focus Software, Wixom, MI, USA). The fabrication of the lens was carried out via high-precision lathe turning using the UPC 100 Vision instrument (SCHNEIDER, Ratingen, Germany). The power profile of the ortho-k lens was measured using the CONTEST 2 apparatus (ROTLEX, Omer, Israel). The surface quality was observed under a 200× microscope (ZEISS, Oberkochen, Germany). The fitting of the lens was assessed through the utilization of both Slit-lamp microscopy (MediWorks, Shanghai, China) and Corneal topographer (Medmont E300, Melbourne, VIC, Australia) [ABSTRACT FROM AUTHOR]

Orthokeratology (OK) is widely used for effective myopia correction and control. However, the incomplete understanding of its biomechanical mechanisms makes OK lens fitting rely heavily on clinician judgment, complicating accurate predictions of treatment outcomes. In this paper, we performed clinical experiments and numerical analysis to study corneal deformation modes and long-term changes in central corneal thickness. Clinical experiments were conducted on 194 Chinese myopic patients under OK treatment for 3 months. Based on the experimental data, a patient-specific computational biomechanical model for OK was established and validated. Specifically, the anisotropic mechanical properties of the cornea were incorporated into the model to describe the significant difference between its shear modulus (29.5 kPa) and tensile modulus (768.4 kPa). Additionally, a visco-hyperelastic material model with a prolonged corneal relaxation time of 5.6 h was developed to capture the long-term deformation response. The results show that corneal thickness reduction in OK is primarily due to out-of-plane shear deformation, influenced by the cornea’s low shear resistance. Modeling the extended corneal relaxation time is crucial for predicting long-term biomechanical responses. The computational model effectively captures long-term changes in central corneal thickness, potentially improving OK lens fitting accuracy. [ABSTRACT FROM AUTHOR]

AIM: To investigate the alterations in corneal aberration and relative refractive power following the reduction of back optic zone diameters(BOZD)of orthokeratology lenses.METHODS: Myopic children aged 8-12 years, deemed suitable and willing to wear orthokeratology lenses, were randomly allocated to wear lenses with a 6.0 mm BOZD or a 5.0 mm BOZD. Data collection included changes in higher-order aberrations, relative refractive power and the treatment zone diameter of the two groups after wearing lenses for 1 d, 1 wk, 1, and 3 mo. The correlation of increase in corneal higher-order aberrations with refractive power was analyzed.RESULTS: The increases in total higher-order aberrations, spherical aberrations and coma aberrations varied over time following lens wear(all P0.05). A significant difference was observed in the increment of spherical aberrations in the 5 mm range between the two groups of patients, which varied over time(Ftime=40.179, Ptime

Abstract Purpose To explore the associations between myopia defocus dosage (MDD), aberration coefficients (primary spherical aberration and coma), and axial elongation in children undergoing orthokeratology (ortho-k) with back optic zone diameters (BOZD) of 5 mm and 6 mm over 2 years. Methods Data from 80 participants from two ortho-k studies were analyzed: 22 and 58 children wore lenses with 5-mm and 6-mm BOZD, respectively. Four MDD metrics were calculated from corneal topography data over a 5-mm pupil for the 1-month and 24-month visits: the circumferential, flat, steep, and volumetric MDD. Corneal primary spherical aberration and comatic aberrations were also extracted from topography data over a 5-mm pupil. Linear mixed modelling was performed to explore the associations between the MDD, corneal aberrations, and axial elongation over 2 years, while controlling for confounding factors (e.g., baseline age and sex). Results Participants in the 5-mm BOZD group displayed less axial elongation than the 6-mm BOZD group over 2 years (0.15 ± 0.21 mm vs. 0.35 ± 0.21 mm, P 0.05). Less axial elongation was associated with a greater volumetric MDD at the 1- and 24-month visits (both β = –0.01, P 0.05). Conclusions The volumetric MDD over a 5-mm pupil after 1 month of ortho-k lens wear was associated with axial elongation after 24 months, and may be a useful predictor of future axial elongation in children undergoing ortho-k.

AIM: To compare the progression of myopia in children wearing orthokeratology lenses combined with low-concentration atropine before and after drug withdrawal, to determine the rebound effect of drug withdrawal in orthokeratology lens wearers, and to analyze its causes based on changes in pupil diameter.METHODS:A prospective case-control study was conducted to collect 80 children with myopia who were treated with orthokeratology lenses combined with 0.01% atropine ophthalmic gel at the Xi'an No.1 Hospital from January to June 2022. One year later, they were divided into a drug withdrawal group(Group A, 40 cases)and a continuous medication group(Group B, 40 cases)based on whether they stopped taking the medication. The progression of myopia before and after drug withdrawal was observed by analyzing changes in axial length(AL)and spherical equivalent(SE)in the group A within 1 a before and after drug withdrawal. The changes in AL, pupil diameter(PD), and SE were compared between the group A and group B within 2 a, and the correlation between PD and AL growth was analyzed.RESULTS:In the group A, the AL increased by 0.17±0.23 and 0.29±0.18 mm at 0.5 and 1 a after drug withdrawal, respectively, which were both greater than before drug withdrawal(t=5.318, 2.983, both P0.05). There were no statistically significant differences in AL and PD between the group A and group B at baseline, 0.5 and 1 a during combined medication(all P>0.05). At 1.5 a, the AL growth of the group A was greater than that of the group B(0.32±0.27 mm vs 0.26±0.20 mm, t=7.363, P

AIM: To elucidate whether differences exist in the impact on retarding the elongation of axial length (AL) among children with myopia when utilizing orthokeratology (ortho-k) lenses employing the corneal refractive therapy (CRT) design versus those employing the vision shaping treatment (VST) design. METHODS: This retrospective clinical trial aimed to collect and analyze AL data from individuals who wore ortho-k lenses for three years. A total of 654 subjects were enrolled and prescribed one of the three specific brands of ortho-k lenses: CRT, Euclid, and Mouldway. The study's primary focus was to compare the rates of AL elongation and myopic progression across these three brands of ortho-k lenses. RESULTS: In the 3-year follow-up, the AL elongation exhibited variations of 0.73±0.36 mm in the CRT lens group, 0.59±0.37 mm in the Euclid lens group, and 0.63±0.38 mm in the Mouldway lens group. A noteworthy disparity emerged between the CRT and Mouldway groups (P

AIM: To observe the effect of orthokeratology combined with vision therapy and Clouclip(OCVTC)on myopic children with dysfunctional accommodation.METHODS: A prospective, non-randomized control study was conducted on 99 myopic children(99 eyes)with dysfunctional accommodation at the optometry center were of Langfang Aier Eye Hospital from April 2022 to January 2023. and they selected and divided into three groups: 39 children in OCVTC group, 30 in orthokeratology(Ortho-k)group, and 30 in single vision spectacle lens(SVL)group. The OCVTC group received office-based accommodative therapy for 3 mo and home reinforcement for 3 mo, and Clouclip was used in the first 3 wk to monitor and remind children of eye habits; the accommodative amplitudes and facility were measured at baseline, 3, 6, and 12 mo after treatment.RESULTS: The OCVTC group showed significantly better improvement in accommodative amplitude compared with both the Ortho-k group and the SVL group(all P

AIM:To explore the effect of the peripheral defocus spectacle lenses and orthokeratology(OK)on the control of myopia progression and the impact on vision related quality of life in children and adolescents.METHODS:Prospective study. A total of 237 children initially diagnosed with myopia in the ophthalmology department of Huzhou Central Hospital from January 2021 to January 2022 were selected and divided into two groups according to different correction methods: peripheral defocus spectacle lenses group(105 cases, 105 eyes)and OK lens group(132 cases, 132 eyes). The Vision Related Quality of Life Questionnaire for Primary and Secondary School Students was used to follow up the both groups of myopic children, and the best corrected visual acuity(BCVA), spherical equivalent(SE), and axial length(AL)were recorded at the first visit and 1 a of follow-up.RESULTS:After wearing lenses for 1 a, both the peripheral defocus spectacle lenses group and OK lens group showed an increase in SE and AL, but there was no statistical difference between two groups(P>0.05). The changes in SE and AL in the peripheral defocus spectacle lenses group were greater than those in the OK lens group(all P=0.001). After 1 a of follow-up, in the emotional dimension scores, the peripheral defocus spectacle lenses group of children's vision-related quality of life scales scored higher than in the OK lens group(P

Background/Objectives: The objective of this study was to examine the trend of treatment zone (TZ) decentration over 12 months of orthokeratology (OK) wear using two Corneal Refractive Therapy (CRT) lens designs: standard (STD) and dual axis (DA). Methods: A prospective, randomized, longitudinal study was conducted at the Optometry Clinic of the Complutense University of Madrid. Subjects were randomly fitted with an STD design or DA design in one of the eyes. Refraction, uncorrected visual acuity (VA), and corneal topography were performed at baseline and after 1 night, 1 week, and 1, 3, 6, and 12 months of lens wear. Subjects requiring lens parameter adjustments or replacements after 3 months were excluded. Decentration was measured by subtracting pre-OK from post-OK tangential curvature maps at each visit, with decentration distance and corneal optical TZ being measured using MATLAB. Correlations between decentration and visual acuity (VA) were also analyzed. Results: A total of 30 healthy children (17 females and 13 males) with a mean age of 12.83 ± 2.42 years (range: 8–17 years) completed all the visits. No statistically significant differences (p > 0.05) were found between lens designs in horizontal, vertical, nor total decentration through the visits. However, for the STD design, horizontal and total decentration increased significantly at the last visit (p < 0.05). For the DA design, no significant differences were found over time (p > 0.05). No correlation was found between decentration and VA. Conclusions: Total decentration in both lens designs was similar throughout one year of follow-up. The standard design tended to decenter horizontally during the last 6 months, while the dual-axis design maintained consistent decentration throughout the year. [ABSTRACT FROM AUTHOR]

Orthokeratology (OK) lenses are designed to reshape the cornea overnight, allowing users to see clearly during the day without glasses. However, prolonged wear increases the risk of microbial contamination and eye infections. Even with cleaning techniques, the surface of OK lenses can become contaminated due to residual bacterial debris. Therefore, developing self-cleaning antibacterial technology for OK lens surfaces is an urgent clinical challenge. Herein, we integrated the temperature responsiveness of PNIPAM molecular chains with the surface contact-killing mechanism of AMP into the surface of OK lenses for the first time, constructing an intelligent OK lens with synergistic antibacterial and self-cleaning properties. The modified OK lenses can achieve over 95% bacterial efficiency against Staphylococcus aureus and Pseudomonas aeruginosa. More importantly, in both worn and removed states, the modified OK lenses can achieve a surface bacterial debris self-cleaning efficiency of 50–75%. These research findings provide important references and insights for the future development of more efficient self-cleaning lens materials. [ABSTRACT FROM AUTHOR]

Purpose: The study analyzed the changes in corneal surface shape after replacing orthokeratology lenses carrying a small base curve (BC) diameter. Methods: In this retrospective study, we included ~54 right eyes belonging to 54 myopic children who insisted on wearing an orthokeratology (ortho-k BC 6.0 mm) lens for more than 12 months and then replaced the second ortho-k (BC 6.0 mm or BC 5.0 mm) lens ~12 months. The children were categorized into two groups based on the design of the BC of the replaced ortho-k lens 6.0/5.0 and 6.0/6.0. Results: The ratio of axial length (AL) elongation in the 6.0/5.0 group was significantly less than in the 6.0/6.0 group (−0.015 ± 0.014 mm/M vs. −0.005 ± 0.012 mm/M, t = −2.672, P = 0.010). After replacing the BC 5.0 ortho-k lens, the optical zone (8.19 ± 2.60 mm2 vs. 9.64 ± 1.57 mm2, t = −2.345, p = 0.023), reverse zone (31.64 ± 5.80 mm2 vs. 34.86 ± 4.61 mm2, t = −2.169, p = 0.035), and treatment zone (17.16 ± 3.94 mm2 vs. 22.96 ± 2.59 mm2, t = −6.049, p < 0.001) were all smaller than those in the 6.0/6.0 group. In the 6.0/5.0 group, the optical zone (wearing more than 1 month as first: 11.16 ± 2.12 mm2, the last inspection before replacing lens as before: 10.87 ± 1.90 mm2), reverse curve zone (first: 22.03 ± 3.11 mm2, before: 26.24 ± 5.06 mm2), and treatment zone (first: 35.97 ± 5.54 mm2, before: 37.11 ± 6.04 mm2) were all greater than these after replacing ortho-k lens (all P < 0.001). Conclusion: Replacing an ortho-k lens with a smaller BC resulted in a larger decrease in the mean central corneal zone and a substantial increase in the paracentral corneal zone. In addition, the ortho-k lens with a smaller BC does not increase the decentration distance and contributes to effective myopia control. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the 1‐year effects of orthokeratology (OK) lenses and spectacle lenses with highly aspherical lenslets (HALs) on axial length (AL) elongation in children with unilateral myopic anisometropia. Methods: This ambispective cohort study recruited 81 children aged 8–14 years with unilateral myopic anisometropia. Of these, 42 participants (mean age 11.07 ± 1.54 years; 23 males) were treated with monocular OK lenses (OK group), and 39 (mean age 10.64 ± 1.72 years; 22 males) with binocular HALs (HAL group). Changes in AL and spherical equivalent refraction (SER) from baseline at 3, 6 and 12 months were compared between eyes and groups. Kaplan–Meier estimation and Cox proportional hazard regression were performed to analyse the risk of myopia onset in the initially non‐myopic eyes. Results: Mean axial elongation in the myopic and non‐myopic eyes at the 12‐month follow‐up visit were 0.17 ± 0.20 and 0.41 ± 0.26 mm in the OK group (p < 0.001) and 0.10 ± 0.15 and 0.12 ± 0.12 mm in the HAL group (p = 0.32), respectively. Compared with the OK group, the non‐myopic eyes in the HAL group had less axial elongation, lower cumulative myopia incidence and percentage of participants with rapid myopic shift at the 6‐ and 12 month follow‐up (all p < 0.05). Cox regression analysis showed that a higher initial SER decreased the risk of myopia onset significantly in the initially non‐myopic eyes (B = −2.06; 95% CI, 0.03–0.49; p = 0.003). Conclusions: Monocular OK lenses suppressed axial elongation in the myopic eye and minimised anisometropia; however, the non‐treated contralateral eye may experience faster myopia onset and myopic shift. Binocular HALs can effectively reduce axial elongation in both eyes of children with unilateral myopic anisometropia. [ABSTRACT FROM AUTHOR]

To investigate the efficacy and safety of repeated low-level red-light (RLRL) therapy combined with orthokeratology among children who, despite undergoing orthokeratology, exhibited an axial elongation of at least 0.50 mm over 1 year. Multicenter, randomized, parallel-group, single-blind clinical trial (ClinicaTrials.gov identifier, NCT04722874). Eligible children were 8–13 years of age with a cycloplegic spherical equivalent refraction of –1.00 to –5.00 diopters at the initial orthokeratology fitting examination and had annual axial length (AL) elongation of ≥0.50 mm despite undergoing orthokeratology. Forty-eight children were enrolled from March 2021 through January 2022, and the final follow-up was completed in March 2023. Children were assigned randomly to the RLRL therapy combined with orthokeratology (RCO) group or to the orthokeratology group in a 2:1 ratio. The orthokeratology group wore orthokeratology lenses for at least 8 hours per night, whereas the RCO group received daily RLRL therapy twice daily for 3 minutes in addition to orthokeratology. The primary outcome was AL change measured at 12 months relative to baseline. The primary analysis was conducted in children who received the assigned intervention and completed at least 1 follow-up after randomization using the modified intention-to-treat principle. Forty-seven children (97.9%) were included in the analysis (30 in the RCO group and 17 in the orthokeratology group). The mean axial elongation rate before the trial was 0.60 mm/year and 0.61 mm/year in the RCO and orthokeratology groups, respectively. After 12 months, the adjusted mean AL changes were –0.02 mm (95% confidence interval [CI], –0.08 to +0.03 mm) in the RCO group and 0.27 mm (95% CI, 0.19–0.34 mm) in the orthokeratology group. The adjusted mean difference in AL change was –0.29 mm (95% CI, –0.44 to –0.14 mm) between the groups. The percentage of children achieving an uncorrected visual acuity of more than 20/25 was similar in the RCO (64.3%) and orthokeratology (65.5%) groups (P = 0.937). Combining RLRL therapy with orthokeratology may offer a promising approach to optimize axial elongation control among children with myopia. This approach also potentially allows children to achieve satisfactory visual acuity, reducing daytime dependence on corrective eyewear. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. [ABSTRACT FROM AUTHOR]

Clinical relevance: There are many methods to control the progression of myopia. However, it is currently unknown which method could better control myopia progression: 0.02% atropine eye drops, peripheral myopic defocus design spectacle lenses (PMDSL), or orthokeratology (OK). Background: To compare the efficacy of 0.02% atropine, PMDSL, and OK to control axial length (AL) elongation in children with myopia. Methods: This study was analysed based on a previous cohort study (0.02% atropine group) and retrospective data (PMDSL and OK group). Overall, 387 children aged 6–14 years with myopia − 1.00D to − 6.00D in the three groups were divided into four subgroups according to age and spherical equivalent refraction (SER). The primary outcome was changed in AL over 1-year. Results: The mean axial elongation was 0.30 ± 0.21 mm, 0.23 ± 0.16 mm, and 0.17 ± 0.19 mm in the 0.02% atropine, PMDSL, and OK groups, respectively. Multivariate linear regression analyses showed significant differences in axial elongation among the three groups, especially in children aged 6–10, but not in children aged 10.1–14; the corresponding axial elongation was 0.35 ± 0.21 mm, 0.23 ± 0.17 mm, and 0.21 ± 0.20 mm (P < 0.05 between any two groups, except between PMDSL and OK groups at P > 0.05) and 0.22 ± 0.20 mm, 0.21 ± 0.13 mm, and 0.13 ± 0.18 mm (P < 0.05 between any two groups, except between 0.02% atropine and PMDSL groups at P > 0.05) in children with SER from − 1.00D to − 3.00D and from − 3.01D to − 6.00D, respectively. Conclusions: Within the limits of this study design and using only the current brand of PMDSL, OK appeared to be the best method, followed by PMDSL and then 0.02% atropine, for controlling AL elongation over one year. However, different effects were found in the various age and SER subgroups. [ABSTRACT FROM AUTHOR]

Purpose Methods Results Conclusion The purpose of this study is to investigate 3‐year efficacy of orthokeratology lenses (OKL) in controlling axial length progression in myopic Scandinavian children. Through a cross‐over design of the control group to compare the treatment efficacy in younger versus older children, with the latter having higher cycloplegic spherical refractive error (cSEQ) at treatment initiation. Further, the study aimed to evaluate the safety of the treatment.This was a continuation of the randomized controlled study Clinical study Of Near‐sightedness; TReatment with Orthokeratology Lenses (CONTROL study) in which the follow‐up period of the original intervention group, that received OKL, was extended from 18 months to 36 months. Meanwhile, the original control group was crossed‐over to OKL after the 18‐month follow‐up visit and treated for 18 months. Biometry was measured using Lenstar LS900, and contact lens complications were graded according to Efron Grading Scale for Contact Lens Complications (Efron score). Mixed models were used for statistical analysis.Nineteen subjects in the OKL group and 28 in the control group completed the CONTROL study. Hereof, 17 and 24 subjects from the OKL group and control group, respectively, agreed to participate in the CONTROL2 study. In the OKL continue group, the treatment efficacy did not decline during the 3‐year study period (p‐values for follow‐up visits were all ≥0.82). There was no statistically significant difference between treatment efficacy when OKL treatment was initiated in younger versus older children (p‐value ≥0.14 for all follow‐up visits). Low‐grade corneal staining was seen in several subjects at some point during the study, but here were no treatment‐requiring or sight‐threatening adverse events during the study period.The efficacy of myopia control by OKL was stable during 3 years of treatment. Similar treatment efficacies were found regardless of the age at treatment initiation. No severe adverse events occurred during the study period. [ABSTRACT FROM AUTHOR]

Background: Approximately, 10% of people report a penicillin allergy; however, more than 90% can safely undergo delabeling after a detailed history, oral challenge, or other investigations such as penicillin skin testing (PST). Although PST is the gold standard, the results can be heterogeneous, and awaiting specialist assessment may take an inordinate amount of time. Therefore, oral provocation challenge has become acceptable for individuals with low-risk penicillin allergy histories. There also appears to be an association with increased prevalence of adverse drug reaction reporting in female individuals, which may translate to penicillin allergy prevalence; however, the evidence has not been assessed through a sex and gender lens. This systematic review will identify and synthesize the findings from studies that report measures of effectiveness and safety of interventions aimed at delabeling penicillin allergies in low-risk individuals. Information related to sex and gender will be extracted, where available, to understand potential differences in allergy reporting and patient outcomes. Methods: The Cochrane Handbook for Systematic Reviews of Interventions and the Centre for Review and Dissemination's Guidance for Undertaking Reviews in Health Care will be used as frameworks for conducting this systematic review. The literature search will be conducted by a medical librarian (B. M. M.) and will consist of a search strategy to identify and retrieve published studies that meet our inclusion criteria. Studies that require penicillin skin testing (PST) as a step prior to other interventions will be excluded. Integrated knowledge translation involving co-design was carried out for this systematic review protocol creation. Data extraction will be conducted at four levels: (1) study level, (2) patient level, (3) intervention level, and (4) outcome level. A narrative descriptive synthesis of results and risk of bias of all included studies will be provided, and, if relevant, a meta-analysis will be performed. Discussion: The dissemination of findings from this knowledge synthesis to various stakeholders is intended to inform on options for evidence-based interventions to aid in delabeling penicillin allergies in individuals with a low risk of experiencing a hypersensitivity reaction. Detailed reporting on the characteristics of delabeling interventions as well as the effectiveness of similar interventions will benefit policy makers considering the implementation of a penicillin allergy delabeling protocol. Additionally, findings from this systematic review will report on the current evidence regarding the role of sex and gender in both the prevalence and outcomes associated with the presence of penicillin allergies. Systematic review registration: PROSPERO CRD42022336457. [ABSTRACT FROM AUTHOR]

PurposeUsing deep learning model to observe the blinking characteristics and evaluate the changes and their correlation with tear film characteristics in children with long-term use of orthokeratology (ortho-K).Methods31 children (58 eyes) who had used ortho-K for more than 1 year and 31 age and gender-matched controls were selected for follow-up in our ophthalmology clinic from 2021/09 to 2023/10 in this retrospective case-control study. Both groups underwent comprehensive ophthalmological examinations, including Ocular Surface Disease Index (OSDI) scoring, Keratograph 5M, and LipiView. A deep learning system based on U-Net and Swim-Transformer was proposed for the observation of blinking characteristics. The frequency of incomplete blinks (IB), complete blinks (CB) and incomplete blinking rate (IBR) within 20 s, as well as the duration of the closing, closed, and opening phases in the blink wave were calculated by our deep learning system. Relative IPH% was proposed and defined as the ratio of the mean of IPH% within 20 s to the maximum value of IPH% to indicate the extent of incomplete blinking. Furthermore, the accuracy, precision, sensitivity, specificity, F1 score of the overall U-Net-Swin-Transformer model, and its consistency with built-in algorithm were evaluated as well. Independent t-test and Mann-Whitney test was used to analyze the blinking patterns and tear film characteristics between the long-term ortho-K wearer group and the control group. Spearman’s rank correlation was used to analyze the relationship between blinking patterns and tear film stability.ResultsOur deep learning system demonstrated high performance (accuracy = 98.13%, precision = 96.46%, sensitivity = 98.10%, specificity = 98.10%, F1 score = 0.9727) in the observation of blinking patterns. The OSDI scores, conjunctival redness, lipid layer thickness (LLT), and tear meniscus height did not change significantly between two groups. Notably, the ortho-K group exhibited shorter first (11.75 ± 7.42 s vs. 14.87 ± 7.93 s, p = 0.030) and average non-invasive tear break-up times (NIBUT) (13.67 ± 7.0 s vs. 16.60 ± 7.24 s, p = 0.029) compared to the control group. They demonstrated a higher IB (4.26 ± 2.98 vs. 2.36 ± 2.55, p < 0.001), IBR (0.81 ± 0.28 vs. 0.46 ± 0.39, p < 0.001), relative IPH% (0.3229 ± 0.1539 vs. 0.2233 ± 0.1960, p = 0.004) and prolonged eye-closing phase (0.18 ± 0.08 s vs. 0.15 ± 0.07 s, p = 0.032) and opening phase (0.35 ± 0.12 s vs. 0.28 ± 0.14 s, p = 0.015) compared to controls. In addition, Spearman’s correlation analysis revealed a negative correlation between incomplete blinks and NIBUT (for first-NIBUT, r = −0.292, p = 0.004; for avg-NIBUT, r = −0.3512, p < 0.001) in children with long-term use of ortho-K.ConclusionThe deep learning system based on U-net and Swim-Transformer achieved optimal performance in the observation of blinking characteristics. Children with long-term use of ortho-K presented an increase in the frequency and rate of incomplete blinks and prolonged eye closing phase and opening phase. The increased frequency of incomplete blinks was associated with decreased tear film stability, indicating the importance of monitoring children’s blinking patterns as well as tear film status in clinical follow-up.

Orthokeratology(OK lens)is considered to be one of the most effective optical treatments for myopia control. Its safety and efficiency in controlling myopia progression have been rigorously verified by numerous studies. As the materials and technology of lens have evolved, orthokeratology has demonstrated remarkable results in myopia control, particularly among children with moderate myopia. Not only does orthokeratology effectively decelerate axial length growth, but it also positively impacts regulatory function. However, it is crucial to acknowledge that there may be some compromise in visual quality. Therefore, the perfect balance between lens design and patient adaptability must be considered to maintain visual clarity and optimize myopia control. While orthokeratology has made significant strides in myopia control, there are still lingering questions about its long-term stability, the precise impact of visual quality, and the others. Furthermore, combining orthokeratology with other strategies offers better effects. Nevertheless, further clinical data is needed to estimate the rebound effects of withdrawal. This review summarizes the technology, safety, efficacy and combination therapy of orthokeratology on myopia control.

AIM: To assess the gap between the peak of the base curve to the surface of the cornea, as well as examines the correlation between the thickness of the tear film and the fitting of the orthokeratology lens through optical coherence tomography(OCT), providing an intuitive and quantitative clinical evaluation method for the fitting of the orthokeratology lens.METHODS: Myopia patients who fitted orthokeratology at our hospital from January to December 2023 were included. Examinations, including naked vision, slit lamp, non-contact intraocular pressure, ocular fundus, eye position, corneal diameter, corneal topography, tear film rupture time, optometry, etc., were performed on all patients before fitting. The trial lens parameter was selected according to the examination results, and fluorescein staining was performed to evaluate lens fitting state after patients adapted to wearing glasses. According to the performance of fluorescein staining, the inspected eyes are divided into three groups: lens loose group, lens fitting group, and lens tight group. In addition, the tear film thickness of three groups of subjects was measured by OCT, and the differences between the three groups of data were evaluated.RESULTS: A total of 49 myopic patients(77 eyes)were included. The average sphere degree was -3.10±1.25 D, the average cylinder degree was -0.43(-0.75, 0)D, the average horizontal keratometry(HK)was 42.48±0.81 D, and vertical keratometry(VK)was 42.98(42.25, 43.50)D. There were 21 cases(34 eyes)in the lens fitting group, with 13 cases of bilateral eyes, 8 cases of one eye, 14 cases(22 eyes)in the lens loose group, with 8 cases of bilateral eyes, 6 cases of one eye, and 14 cases(21 eyes)in the lens tight group, with 7 cases of bilateral eyes, 7 cases of one eye. There was no statistical difference in the main basic data of the subjects in the three groups(all P>0.05). OCT showed that the tear film thickness of the lens fitting group, the lens loose group, and the lens tight group was 231.18(219.0, 243.0), 220.41(214.0, 224.3), and 249.00(241.5, 258.0)μm, respectively, and there was statistical significance in the thickness among the three groups(P

AIM: To compare the clinical effectiveness of using multifocal defocus spectacle lenses, orthokeratology lenses, and single-vision spectacle lenses in patients with myopia and small-angle intermittent exotropia.METHODS: This retrospective study included 150 patients aged 8-15 years with basic intermittent exotropia, strabismus of -10△ to -20△ prism diopters(D)(block lenses), and spherical equivalents of -1.00 to -5.50 D, who visited our hospital from June 2021 to September 2022. They were selected and divided into three groups on a voluntary basis: the HAL group(50 patients with multifocal myopia defocus spectacle lenses), the OK lens group(50 patients with nighttime orthokeratology lenses), and the SVL group(50 patients with regular single-vision spectacle lenses). After wearing the lenses consistently, changes in axial length, prism diopters with the naked eye and lenses(prism at 33 cm), positive fusional vergence of blurred points, and near stereopsis were observed and compared among groups before intervention and after 1 a. The Newcastle control score(NCS)was used to evaluate the eye position control ability of the patients in the three groups.RESULTS: Before the intervention, the axial lengths of the HAL, OK lens, and SVL groups were 24.83±0.91, 24.93±0.97, and 24.98±0.68 mm, respectively(P>0.05). After 1 a, the axial lengths of the three groups were 25.02±0.90, 25.18±0.97, and 25.45±0.65, respectively(P0.05). After 1 year, near stereopsis in the groups were 76.00″±20.40″, 81.20″±18.91″, and 100.60″±51.41″, respectively(P0.05), and it was 17.10±2.02, 13.12±1.41, and 13.26±2.45, respectively, after 1 a(P

Purpose: To investigate axial elongation (AE) and changes in relative peripheral refraction (RPR) in anisomyopic children undergoing orthokeratology (ortho‐k). Methods: Bilateral anisomyopic children, 7–12 years of age, were treated with ortho‐k. Axial length (AL) and RPR, from 30° nasal (N30°) to 30° temporal (T30°), were measured at baseline and every 6 months over the study period. AE, changes in RPR and changes in the interocular AL difference were determined over time. Results: Twenty‐six of the 33 subjects completed the 2‐year study. The AE of the higher myopic (HM) eyes (at least 1.50 D more myopia than the other eye) (0.26 ± 0.29 mm) was significantly smaller than for the less myopic (LM) eyes (0.50 ± 0.27 mm; p = 0.003), leading to a reduction in the interocular difference in AL (p = 0.001). Baseline RPR measurements in the HM eyes were relatively more hyperopic at T30°, N20° and N30° (p ≤ 0.02) and greater myopic shifts were observed at T20° (p < 0.001), T30° (p < 0.001), N20° (p = 0.02) and N30° (p = 0.01) after lens wear. After 2 years of ortho‐k lens wear, temporal–nasal asymmetry increased significantly, being more myopic at the temporal locations in both eyes (p < 0.001), while AE was associated with the change in RPR at N20° (β = 0.134, p = 0.01). The interocular difference in AE was also positively associated with the interocular difference in RPR change at N30° (β = 0.111, p = 0.02). Conclusions: Ortho‐k slowed AE in bilateral anisomyopia, with slower growth in the HM eyes leading to a reduction in interocular AL differences. After ortho‐k, RPR changed from hyperopia to myopia, with greater changes induced in the HM eyes, and slower AE was associated with a more myopic shift in RPR, especially in the nasal field of both eyes. [ABSTRACT FROM AUTHOR]

Purpose: To optimise the precision and efficacy of orthokeratology, this investigation evaluated a deep neural network (DNN) model for lens fitting. The objective was to refine the standardisation of fitting procedures and curtail subjective evaluations, thereby augmenting patient safety in the context of increasing global myopia. Methods: A retrospective study of successful orthokeratology treatment was conducted on 266 patients, with 449 eyes being analysed. A DNN model with an 80%–20% training‐validation split predicted lens parameters (curvature, power and diameter) using corneal topography and refractive indices. The model featured two hidden layers for precision. Results: The DNN model achieved mean absolute errors of 0.21 D for alignment curvature (AC), 0.19 D for target power (TP) and 0.02 mm for lens diameter (LD), with R2 values of 0.97, 0.95 and 0.91, respectively. Accuracy decreased for myopia of less than 1.00 D, astigmatism exceeding 2.00 D and corneal curvatures >45.00 D. Approximately, 2% of cases with unique physiological characteristics showed notable prediction variances. Conclusion: While exhibiting high accuracy, the DNN model's limitations in specifying myopia, cylinder power and corneal curvature cases highlight the need for algorithmic refinement and clinical validation in orthokeratology practice. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anatolian Clinic Journal of Medical Sciences is the property of Hayat Saglik ve Sosyal Hizmetler Vakfi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To observe the effectiveness and safety of long-term wearing of orthokeratology lens in adolescent myopia patients. Methods: From June 2019 to April 2023, 30 myopic adolescents (60 eyes) who had been fitted with orthokeratology lens in the ophthalmology department of Xuanwu hospital and had worn them for a long time (≥ 3 years) were reviewed. They were reexamined 1 day, 7 days, 1 month and 3 month after wearing the glasses. The changes of the axial length and the parameters of corneal endothelioscopy were compared before and after wearing the glasses for 6 months, 1 year, 2 years and 3 years. Result: A total of 30 cases (60 eyes) were observed in this study, including 13 males and 17 females, aged 7-14 years old, with an average age of 9.77 ± 1.89 years old. The equivalent spherical scope was -5.00-0.75D, with an average of -1.98± 0.97 D. Among them, 5 cases (8 eyes, 13.3%) developed grade 1 corneal staining, but no grade 2-3 staining was observed. 2 cases (4 eyes, 6.7%) developed allergic conjunctivitis, which was cured after stopping wearing and receiving corresponding treatment. The axial lengths of 6 mon, 1 a, 2 a, and 3 a before and after wearing glasses were 24.57± 0.74 mm, 24.67± 0.85 mm, 24.78± 0.96 mm, 24.91± 0.97 mm, and 25.06± 0.85 mm, respectively, showing an overall increasing trend (F=21.904, P<0.001). There were statistically significant differences in axial lengths between pre and post wearing glasses at various time points, with P values of 0.027, 0.001, 0.000, and 0.000, respectively. There was a statistically significant difference between 6 mon after wearing glasses and 1 a, 2 a, and 3 a after wearing glasses. The P-values were 0.005, 0.000, and 0.008, respectively. There was a statistically significant difference (P<0.001) between 1 year after wearing the mirror and 2 years after wearing the mirror, while there was no statistically significant difference (P>0.05) between other time points. The coefficient of variation of cell area at 6 mon, 1 a, 2 a, and 3 a before and after wearing glasses were 25± 2.9%, 26± 3.7%, 27± 4.1%, 27± 4.6%, and 27± 4.1%, respectively. Overall, F=5.490, P=0.001. Comparing the two groups, it was found that there was a statistically significant difference between the two groups, with P values of 0.012 and 0.008, respectively (P<0.05). The difference between the two groups was statistically significant (P=0. 007), There was no statistically significant difference between other time points (P>0.05). There was no statistically significant difference in corneal thickness, endothelial cell density, average area, and hexagonal cell ratio at each time point (P>0.05).Conclusion: Adolescent myopia patients can effectively control the rapid growth of their eye axis by wearing corneal reshaping lenses for a long time. However, comprehensive examination and evaluation must be conducted, qualified and appropriately sized lenses must be worn, standardized operations must be carried out, and follow-up visits must be made on time. If allergies or corneal injuries occur, timely cessation of wearing and corresponding treatment can ensure the safety of long-term wearing. Morphological examination of corneal cells revealed that long-term wearing of glasses showed an increasing trend in the variation of corneal endothelial cell area. [ABSTRACT FROM AUTHOR]

Background: A pro-oxidant enzyme, NADPH oxidase 4 (Nox4) has been reported to be a critical downstream effector of TGFβ-induced myofibroblast transformation during fibrosis. While there are a small number of studies suggesting an oncogenic role of Nox4 derived from activated fibroblasts, direct evidence linking this pro-oxidant to the tumor-supporting CAF phenotype and the mechanisms involved are lacking, particularly in breast cancer. Methods: We targeted Nox4 in breast patient-derived CAFs via siRNA-mediated knockdown or administration of a pharmaceutical inhibitor (GKT137831). We also determine primary tumor growth and metastasis of implanted tumor cells using a stable Nox4-/- syngeneic mouse model. Autophagic flux of CAFs was assessed using a tandem fluorescent-tagged ptfl-LC3 plasmid via confocal microscopy analysis and determination of the expression level of autophagy markers (beclin-1 and LC3B). Nox4 overexpressing CAFs depend on the Nrf2 (nuclear factor-erythroid factor 2-related factor 2) pathway for survival. We then determined the dependency of Nox4-overexpressing CAFs on the Nrf2-mediated adaptive stress response pathway for survival. Furthermore, we investigated the involvement of Birc5 on CAF phenotype (viability and collagen contraction activity) as well as the expression level of CAF markers, FAP and αSMA. Conclusions: We found that deletion of stroma Nox4 and pharmaceutically targeting its activity with GKT137831 significantly inhibited orthotopic tumor growth and metastasis of implanted E0771 and 4T1 murine mammary carcinoma cell lines in mice. More importantly, we found a significant upregulation of Nox4 expression in CAFs isolated from human breast tumors versus normal mammary fibroblasts (RMFs). Our in situ RNA hybridization analysis for Nox4 transcription on a human breast tumor microarray further support a role of this pro-oxidant in the stroma of breast carcinomas. In addition, we found that Nox4 promotes autophagy in CAFs. Moreover, we found that Nox4 promoted survival of CAFs via activation of Nrf2, a master regulator of oxidative stress response. We have further shown Birc5 is involved as a downstream modulator of Nrf2-mediated pro-survival phenotype. Together these studies indicate a role of redox signaling via the Nox4-Nrf2 pathway in tumorigenesis and metastasis of breast cancer cells by promoting autophagy and survival of CAFs. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize the variations in subfoveal choroidal thickness (SFCT) observed at different follow-up intervals in myopic children undergoing orthokeratology treatment. Relevant articles were systematically retrieved from databases such as PubMed, EMBASE, Web of Science, and Cochrane Library. The retrieval period extended from the inception of these databases to November 2023. Means and standard deviations (SD) of baseline and post-treatment SFCT were selected as the results for analysis and calculation. A total of eight articles involving 478 eyes fulfilled the inclusion criteria. At 1 month, 3 months, and 6 months intervals, the SFCT demonstrated significant increases by 16.74 μm (95% CI: 8.66, 24.82; p < 0.0001), 13.41 μm (95% CI: 4.36, 22.45; p = 0.004), and 17.57 μm (95% CI: 8.41, 26.73; p = 0.0002), respectively. Besides, children treated with orthokeratology exhibited a notably thicker change of SFCT in comparison with children with single-vision spectacles (SVL) (WMD = 13.50, 95% CI: 11.69, 15.13; p < 0.0001). Myopic children undergoing orthokeratology treatment experience a discernible increase in SFCT at 1 month, 3 months, and 6 months. Furthermore, compared to children utilizing SVL, those undergoing orthokeratology manifest a more pronounced thickening of SFCT. [ABSTRACT FROM AUTHOR]

PurposeThe study analyzed the changes in corneal surface shape after replacing orthokeratology lenses carrying a small base curve (BC) diameter.MethodsIn this retrospective study, we included ~54 right eyes belonging to 54 myopic children who insisted on wearing an orthokeratology (ortho-k BC 6.0 mm) lens for more than 12 months and then replaced the second ortho-k (BC 6.0 mm or BC 5.0 mm) lens ~12 months. The children were categorized into two groups based on the design of the BC of the replaced ortho-k lens 6.0/5.0 and 6.0/6.0.ResultsThe ratio of axial length (AL) elongation in the 6.0/5.0 group was significantly less than in the 6.0/6.0 group (−0.015 ± 0.014 mm/M vs. −0.005 ± 0.012 mm/M, t = −2.672, P = 0.010). After replacing the BC 5.0 ortho-k lens, the optical zone (8.19 ± 2.60 mm2 vs. 9.64 ± 1.57 mm2, t = −2.345, p = 0.023), reverse zone (31.64 ± 5.80 mm2 vs. 34.86 ± 4.61 mm2, t = −2.169, p = 0.035), and treatment zone (17.16 ± 3.94 mm2 vs. 22.96 ± 2.59 mm2, t = −6.049, p < 0.001) were all smaller than those in the 6.0/6.0 group. In the 6.0/5.0 group, the optical zone (wearing more than 1 month as first: 11.16 ± 2.12 mm2, the last inspection before replacing lens as before: 10.87 ± 1.90 mm2), reverse curve zone (first: 22.03 ± 3.11 mm2, before: 26.24 ± 5.06 mm2), and treatment zone (first: 35.97 ± 5.54 mm2, before: 37.11 ± 6.04 mm2) were all greater than these after replacing ortho-k lens (all P < 0.001).ConclusionReplacing an ortho-k lens with a smaller BC resulted in a larger decrease in the mean central corneal zone and a substantial increase in the paracentral corneal zone. In addition, the ortho-k lens with a smaller BC does not increase the decentration distance and contributes to effective myopia control.

PurposeThis study analyzed the corneal surface shape following overnight orthokeratology with different optical zone diameters.MethodsA total of 82 eyes belonging to 41 myopic children who completed 1 month of the orthokeratology (ortho-k) lens wear at the Eye Hospital of Wenzhou Medical University from January 2022 to January 2023 were retrospectively analyzed. According to the size of the base curve (BC) of ortho-k lens, patients were divided into BC 5.0 and BC 6.0 groups. The changes in decentration distance and corneal refraction of the two groups after the ortho-k lens wear were analyzed. Independent sample t-tests were used to compare these two outcome measures between the two groups.ResultsThe decentration distance of BC 5.0 group (0.37 ± 0.19 mm) was significantly lower than that of BC 6.0 group (0.49 ± 0.25 mm, t = −2.330, p = 0.022). In the BC 5.0 group, the direction of decentration was superonasal in 3 cases, inferonasal in 2 cases, inferotemporal in 21 cases, and superotemporal in 6 cases. In the BC 6.0 group, the direction of decentration was superonasal in 2 cases, inferonasal in 2 cases, inferotemporal in 27 cases, and superotemporal in 19 cases. The optical zone area (8.19 ± 2.96 mm2) and reverse curve zone area (30.05 ± 6.74 mm2) in the BC 5.0 group were significantly lower than in the BC 6.0 group (10.42 ± 2.03 mm2, t = −4.043, p < 0.001; 38.21 ± 4.77 mm2, t = −6.422, p < 0.001). The change in the rate of refraction in the horizontal direction in BC 5.0 group were significant higher than in BC 6.0 group.ConclusionBase curve 5.0 mm ortho-k lens is better positioned than BC 6.0 mm lens. A small BC ortho-k forms a smaller optical zone and reverse curve area, which might get a greater aiameter of alignment curve to facilitate positioning better than the traditional BC lens. In addition, a small BC lens increases positive refraction in the peripheral area, resulting in a greater negative pressure than the traditional BC lens.