Spectacle Lenses With Aspherical Lenslets for Myopia Control vs Single-Vision Spectacle Lenses: A Randomized Clinical Trial

Mechanisms of emmetropization and what might go wrong in myopia

Studies in animal models and humans have shown that refractive state is optimized during postnatal development by a closed-loop negative feedback system that uses retinal image defocus as an error signal, a mechanism called emmetropization. The sensor to detect defocus and its sign resides in the retina itself. The retina and/or the retinal pigment epithelium (RPE) presumably releases biochemical messengers to change choroidal thickness and modulate the growth rates of the underlying sclera. A central question arises: if emmetropization operates as a closed-loop system, why does it not stop myopia development? Recent experiments in young human subjects have shown that (1) the emmetropic retina can perfectly distinguish between real positive defocus and simulated defocus, and trigger transient axial eye shortening or elongation, respectively. (2) Strikingly, the myopic retina has reduced ability to inhibit eye growth when positive defocus is imposed. (3) The bi-directional response of the emmetropic retina is elicited with low spatial frequency information below 8 cyc/deg, which makes it unlikely that optical higher-order aberrations play a role. (4) The retinal mechanism for the detection of the sign of defocus involves a comparison of defocus blur in the blue (S-cone) and red end of the spectrum (L + M-cones) but, again, the myopic retina is not responsive, at least not in short-term experiments. This suggests that it cannot fully trigger the inhibitory arm of the emmetropization feedback loop. As a result, with an open feedback loop, myopia development becomes "open-loop".

Surgical options and clinical outcomes for high myopia

PURPOSE OF REVIEW

Higher degrees of myopia are currently being treated with refractive surgery. However, there is limited characterization and outcomes data for this cohort. This article aims to review the literature on highly myopic patients who had refractive surgery and present a retrospective analysis of 149 patients (270 eyes) with high to extreme myopia (≤-5.0D SE) who underwent refractive surgery [laser-assisted subepithelial keratomileusis (LASIK), photorefractive keratectomy (PRK), or implantable collamer lense (ICL)] at a single practice.

RECENT FINDINGS

There is substantial literature on the efficacy of LASIK, PRK, and phakic intraocular lenses for refractive error correction, but a dearth of studies on patients with high to extreme myopia undergoing different types of refractive surgery. Our study reveals that this cohort of patients has excellent outcomes with minimal complications.

SUMMARY

Our study reveals that the average preoperative myopia was highest in ICL patients (-10.03D), followed by PRK (-7.21D), and LASIK (-7.04D) patients. Not surprisingly, eyes with high myopia and thin corneas were offered and elected ICLs for their procedure. Highly myopic patients achieved outcomes consistent with data reported in the literature- average postoperative uncorrected visual acuity was 20/20 for LASIK and ICL eyes and 20/25 for PRK eyes.

Comparison of the axial growth with multifocal and monofocal intraocular lenses in unilateral pediatric cataract surgery

PURPOSE

To compare axial growth in pediatric cataract patients who underwent multifocal intraocular lens (IOL) implantation without anterior vitrectomy (AV) with that in pediatric patients who underwent monofocal IOL implantation with or without AV.

METHODS

Patients who had unilateral pediatric cataracts and underwent surgery at 3-6 years of age from June 6, 2019, to June 30, 2020, at our institution were prospectively analyzed. The patients were categorized into Group A: multifocal IOL implantation with optic capture in Berger's space without AV; Group B: monofocal IOL implantation with optic capture in Berger's space without AV; and Group C: bag-in-the-lens monofocal IOL implantation with AV. Groups A', B' and C' consisted of the fellow eyes from the respective groups. Axial growth and monthly growth rates were compared among the 3 treatment groups, as well as between the treated eyes and the fellow eyes.

RESULTS

Thirty-one, 23, and 14 children fulfilling the inclusion criteria, respectively, were included in the final analysis. There were no significant differences in patient age at the time of surgery or preoperative axial length (P > 0.05). After a mean follow-up of 35.57 ± 3.78 months, significant differences in the axial growth and the monthly growth rate were observed (P < 0.05), and Group A had the least axial elongation. Comparing treated eyes with fellow eyes, the amount and rate of axial growth were lower in Group A than in Group A' (P < 0.05), no significant differences were found in Group B (P > 0.05), and Group C had greater growth than did Group C' (P < 0.05).

CONCLUSIONS

The implanting multifocal intraocular lenses and maintenance of vitreous body integrity may be protective factors against excessive axial growth in pediatric cataract patients. Clinical trial registration (prospective study): chiCRT1900023155; 2019-05-14.

Effectiveness of orthokeratology and myopia control spectacles in a real-world setting in China

OBJECTIVE

To compare the effectiveness of myopia control in Chinese children, who had been wearing either orthokeratology (ortho-k) lenses or myopia control spectacles (MCS) for one year.

METHODS

Relevant data were retrieved from 212 patients, with baseline myopia of -5.00 to -0.75 D, astigmatism ≤ 1.50 D, who had been undergoing myopia control treatment with either ortho-k (Euclid (OK1) or CRT (OK2)) or MCS (Stellest (MCS1) or DIMS (MCS2)) for at least one year. Myopia control effectiveness among the four groups was compared based on the change in spherical equivalent refraction (SER) (for the spectacle groups) and axial length (AL) (for all groups). Data retrieved, from the right eye only, included best corrected visual acuity (BCVA), SER, and AL at both the initial clinic visit (baseline) and the one-year visit was analysed.

RESULTS

Although no significant differences in gender, cylindrical power, or BCVA were observed at the baseline visit (P > 0.05), there were significant differences in baseline age, myopia, and AL among the four groups (P < 0.05). No significant difference in axial elongation (AE) was found among the four groups after one year of treatment (P = 0.49). AE, adjusted for baseline age and spherical power, were 0.19 ± 0.15, 0.18 ± 0.14, 0.19 ± 0.19, 0.20 ± 0.18 mm for OK1, OK2, MCS1, MCS2, respectively. Only age was a significantly factor associated with AE and SER increase (P < 0.05), with negative associations between AE and age in all groups and positive association between SER increase and baseline age in the spectacle groups observed.

CONCLUSION

Both brands of ortho-k lenses and MCS had similar myopia control effectiveness for mild to moderate myopic children treated in a real-world setting in China. Average AE in one year ranged from 0.18 to 0.20 mm, comparable to previous reports on myopia control using ortho-k.

Advances in myopia control strategies for children

Myopia has long been a global threat to public health. Timely interventions are likely to reduce the risk of vision-threatening complications. There are both established and rapidly evolving therapeutic approaches to slow myopia progression and/or delay its onset. The effective methods for slowing myopia progression include atropine eye-drops, defocus incorporated multiple segments (DIMS) spectacle lenses, spectacle lenses with highly aspherical lenslets target (HALT), diffusion optics technology (DOT) spectacle lenses, red light therapy (RLT), multifocal soft contact lenses and orthokeratology. Among these, 0.05% atropine, HALT lenses, RLT and +3.00 peripheral addition soft contact lenses yield over 60% reduction in myopia progression, whereas DIMS, DOT and MiSight contact lenses demonstrate at least 50% myopia control efficacy. 0.05% atropine demonstrates a more optimal balance of efficacy and safety than 0.01%. The efficacy of 0.01% atropine has not been consistent and requires further validation across diverse ethnicities. Combining atropine 0.01% with orthokeratology or DIMS spectacles yields better outcomes than using these interventions as monotherapies. Increased outdoor time is an effective public health strategy for myopia prevention while recent studies suggest that 0.05% low-concentration atropine and RLT therapy have promising potential as clinical myopia prevention interventions for high-risk groups. Myopia control spectacle lenses, being the least invasive, are safe for long-term use. However, when considering other approaches, it is essential to ensure proper instruction and regular follow-ups to maintain safety and monitor any potential complications. Ultimately, significant advances have been made in myopia control strategies, many of which have shown meaningful clinical outcomes. However, regular use and adequate safety monitoring over extended durations are imperative to foster confidence that can only come from extensive clinical experience.

Factors influencing myopia stabilisation in young myopic adult Singaporeans

PURPOSE

To evaluate factors influencing stabilisation of myopia in the Singapore Cohort of Risk factors for Myopia.

METHODS

We evaluated the longitudinal natural history of 424 myopic participants from 1999 to 2022. The outcome was the change in myopia from the adolescence follow-up visit (aged 12-19 years) to the adulthood follow-up visit (aged 26-33 years). Association of predictive factors, including baseline spherical error, gender, ethnicity, parental myopia, time outdoor, near work and age at adolescence, was examined with the dichotomous outcome of adult myopia progression (≤ -1.00 dioptres (D) over 10 years) using multiple logistic regression and progression in linear regression models.

RESULTS

For the primary outcome, the mean rate of progression of the outcome was found to be -0.04±0.09 D per year from the adolescent to the adulthood follow-up visits. 82.3% (95% CI 78.3% to 85.8%) had myopia stabilisation, with progression of less than 1.00 D over 10 years while 61.3% (95% CI 56.5% to 66.0%) of the subjects had progression of less than 0.50 D. In logistic regression models, both male gender (p=0.035) and non-Chinese ethnicity (p=0.032) were more likely to achieve myopia stabilisation while in linear multivariate regression models, males had a significantly slower degree of myopia progression (p=0.021).

CONCLUSION

5 in 6 Singaporean young adults had myopia stabilisation. Male gender is 2 times and non-Chinese ethnicities are 2.5 times more likely to achieve myopia stabilisation. However, a proportion of myopes continue to exhibit a clinically significant degree of progression in adulthood.

Peripheral myopic defocus signal affects the efficiency of visual information processing in myopic children

PURPOSE

Spectacle lenses with peripheral lenslets have shown promise for myopia control by providing peripheral myopic defocus signals. Here, we aimed to investigate the impact of prolonged exposure (>6 months) to peripheral myopic defocus on visual information processing in myopic children.

METHODS

The study included 30 myopic children who habitually wore spectacle lenses with highly aspherical lenslets (HAL group) and 34 children who habitually wore single-vision (SV group) spectacles. The quick contrast sensitivity function (qCSF) was used to measure contrast sensitivity (CS) under conditions of no or high noise. Both groups were tested with HAL and SV lenses. The perceptual template model was utilised to fit the contrast sensitivity function (CSF) and determine differences in information processing efficiency through internal additive noise (N add $$ {N}_{\mathrm{add}} $$ ) and perceptual template gain (β).

RESULTS

The areas under the log CSF in the SV group were significantly higher than for the HAL group in both zero-noise conditions with the SV test lens (p = 0.03) and high-noise conditions with the HAL test lens (p = 0.02). For 2 cycle per degree (cpd) stimuli, β was significantly higher in the SV group with the HAL test lens than in the HAL group (p = 0.02), while there was a trend towards a significant difference in β for 6 cpd stimuli (p = 0.07). However, there were no significant differences inN add $$ {N}_{\mathrm{add}} $$ between the two groups, with or without noise interference.

CONCLUSION

The reduced CS observed in myopic children wearing HAL lenses for 6 months or more may be due to decreased β. This suggests that prolonged use of spectacle lenses with peripheral myopic defocus signals may compromise the central visual system's ability to process additional external noise, resulting in decreased efficiency in visual information processing.

A systematic review and meta-analysis of the efficacy of different optical interventions on the control of myopia in children

To compare the treatment efficacy of childhood myopia control optical interventions [spectacles, soft contact lenses (SCLs) and orthokeratology (OK) lenses], explore the consistency of treatment efficacies during the treatment period and evaluate the impact of baseline spherical equivalent refraction (SER), axial length (AL) and age on the treatment effect. A literature search of EMBASE, PubMed and Google Scholar databases identified 220 articles published between January 2000 and April 2022, which reported the treatment efficacy by differences in the SER and AL change between intervention and control groups. Thirty-five articles were included in the analysis. Treatment effect sizes (ESs) were calculated, where more positive and negative directions indicated greater treatment efficacy for SER and AL respectively. For SER, the ESs with peripheral add design spectacles (0.66) and SCLs (0.53) were large but not significantly different between treatment types (p = 0.69). For AL, ESs with peripheral add design spectacles (-0.37), SCLs (-0.55) and OK lenses (-0.93) were large, but OK lenses had a significantly greater effect than peripheral add design spectacles (p ≤ 0.001). ESs were large during the first 12 months of treatment for all interventions [peripheral add design SCLs and OK (F ≥ 5.39, p ≤ 0.01), peripheral add design spectacles (F = 0.47, p = 0.63)] but reduced towards the end of 24-36 months of treatment. Baseline SER had an impact on the treatment effect with peripheral add design spectacles only. Optical interventions are efficacious in controlling childhood myopia progression. However, treatment effects were largest only during the first 12 months of treatment and reduced over time.

A retrospective study of cumulative absolute reduction in axial length after photobiomodulation therapy

BACKGROUND

To assess the age and timeline distribution of ocular axial length shortening among myopic children treated with photobiomodulation therapy in the real world situations.

METHODS

Retrospective study of photobiomodulation therapy in Chinese children aged 4 to 13 years old where axial length measurements were recorded and assessed to determine effectiveness at two age groups (4 ∼ 8 years old group and 9 ∼ 13 years old group). Data was collected from myopic children who received photobiomodulation therapy for 6 ∼ 12 months. Effectiveness of myopia control was defined as any follow-up axial length ≤ baseline axial length, confirming a reduction in axial length. Independent t-test was used to compare the effectiveness of the younger group and the older group with SPSS 22.0.

RESULTS

342 myopic children were included with mean age 8.64 ± 2.20 years and baseline mean axial length of 24.41 ± 1.17 mm. There were 85.40%, 46.30%, 71.20% and 58.30% children with axial length shortening recorded at follow-up for 1 month, 3 months, 6 months and 12 months, respectively. With respect to the axial length shortened eyes, the mean axial length difference (standard deviation) was - 0.039 (0.11) mm, -0.032 (0.11) mm, -0.037 (0.12) mm, -0.028 (0.57) mm at 1, 3, 6, and 12-month follow-up, respectively. Greater AL shortening was observed among the older group who had longer baseline axial lengths than the younger group (P < 0.001).

CONCLUSIONS

Overall myopia control effectiveness using photobiomodulation therapy was shown to be age and time related, with the maximum absolute reduction in axial elongation being cumulative.

Effect of spectacle lenses with aspherical lenslets on choroidal thickness in myopic children: a 3-year follow-up study

BACKGROUND

To investigate the impact of wearing spectacle lenses with highly aspherical lenslets (HAL) for 3 years and the impact of switching from single-vision lenses (SVL) to HAL on choroidal thickness (ChT).

METHODS

Fifty-one participants who had already worn HAL for 2 years continued wearing them for an additional year (HAL group). Further, 50 and 41 participants who had worn spectacle lenses with slightly aspherical lenslets (SAL) and SVL for 2 years, respectively, switched to wearing HAL for another year (SAL-HAL and SVL-HAL groups). Additionally, 48 new participants aged 10-15 years were enrolled to wear SVL at the third year (new-SVL group). ChT was measured every 6 months throughout the study.

RESULTS

Significant differences were observed in the changes in ChT among the four groups at the third year (all P < 0.05 except for the outer nasal region: P = 0.09), with the new-SVL group showing larger reductions compared with the other three groups. However, none of the three HAL-wearing groups showed significant changes in ChT at the third year (all P > 0.05). When comparing the changes in ChT for 3 years among the HAL, SAL-HAL, and SVL-HAL groups, significant differences were found before switching to HAL, but these differences were abolished after all participants switched to HAL.

CONCLUSIONS

Compared to those in the SVL group, choroid thinning was significantly inhibited in all the HAL groups. Wearing HAL for 3 years no longer had a choroidal thickening effect but could still inhibit choroidal thinning compared to wearing SVL.

TRIAL REGISTRATION

The study was registered at the Chinese Clinical Trial Registry (ChiCTR1800017683), http://www.chictr.org.cn/showproj.aspx?proj=29789 .

Visual performance of optical films utilizing Spatio-Temporal Optical Phase technology

SIGNIFICANCE

Spatio-Temporal Optical Phase technology utilizes film pairs containing optical elements applied to standard single-vision spectacle lenses. This technology provides a dynamic optical cue that may have efficacy in reducing the rate of myopia progression, but the visual performance of this technology is unknown.

PURPOSE

This study aimed to assess the visual performance of film pairs containing optical elements (tests) and a film pair with no optical elements (control).

METHODS

In this randomized, single-masked, bilateral wear study, 42 participants aged 18 to 40 years wore four test designs (E, F-1, G, and F-2) and the control. Subjective data (subjective ratings [1 to 10 scale]: clarity of vision [far-away, intermediate, near] and vision [at night, while walking, overall satisfaction], and willingness to purchase [yes/no response]) were collected after 3 days. Visual acuity (VA)-based measures (monocular high/low-contrast VA [6 m], contrast sensitivity [6 m], and binocular high-contrast VA [6 m and 40 cm]) were collected at dispensing. Visual acuity-based measures were also collected while wearing spectacles with no film. Analyses were performed using linear mixed models and the χ2 test. Significance was set at 5%.

RESULTS

The control performed better than any test for all subjective ratings (mean differences, 1.6 to 3.1 units: p<0.001), willingness to purchase (p<0.001), and designs F-1 and F-2 for binocular high-contrast VA at 40 cm (p=0.001 and p=0.01, respectively). Clarity of vision was significantly worse with F-2 compared with F-1 and G (p<0.001 and p=0.02, respectively). There were no differences between tests for any other subjective rating (p>0.1), willingness to purchase (p=0.11), or any VA-based measure (p>0.08). There were no differences between control and spectacles with no film for any VA-based measure (p>0.08).

CONCLUSIONS

All four test film pairs reduced visual performance compared with control to a degree comparable with other myopia management devices. There was no difference in visual performance between three of the four test film pairs.

One-year efficacy of myopia control by the defocus distributed multipoint lens: a multicentric randomised controlled trial

AIMS

To report the 1-year results of the efficacy of a defocus distributed multipoint (DDM) lens in controlling myopia progression in a multicentre, randomised controlled trial.

METHODS

Overall, 168 children aged 6-13 years were recruited and randomly assigned to wear a DDM lens (n=84) or single-vision (SV) lens (n=84) in three centres. Cycloplegic autorefraction (spherical equivalent refraction (SER)) and axial length (AL) were measured. Linear mixed model analysis was performed to compare between-group SER and AL changes. Logistic regression analysis was used to analyse the between-group difference in rapid myopia progression (SER increase≥0.75 D per year or AL growth≥0.40 mm per year).

RESULTS

After 1 year, mean changes in SER were significantly lower in the DDM group (-0.47±0.37 D) than in the SV group (-0.71±0.42 D) (p<0.001). Similarly, mean changes in AL were significantly lower in the DDM group (0.21±0.17 mm) than in the SV group (0.34±0.16 mm) (p<0.001). After adjusting for age, sex, daily wearing time and parental myopia, rapid myopia progression risk was higher in the SV group than in the DDM group (OR=3.51, 95% CI: 1.77 to 6.99), especially for children who wore a lens for >12 hours per day, boys and younger children (6-9 years) with ORs (95% CIs) of 10.82 (3.22 to 36.37), 5.34 (1.93 to 14.78) and 8.73 (2.6 to 29.33), respectively.

CONCLUSIONS

After 1 year, DDM lenses effectively retarded myopia progression in children. Longer daily wearing time of DDM lens improved the efficacy of myopia control. Future long-term studies are needed for validation.

TRIAL REGISTRATION NUMBER

NCT05340699.

Astigmatism and maternal myopia as important factors affecting success rate of DIMS lens treatment

OBJECTIVE

To assess the efficacy of myopia control spectacle lenses (defocus incorporated multiple segments/DIMS) in slowing myopia progression among a diverse Central European paediatric population and investigate the contribution of baseline parameters on treatment outcomes.

METHODS AND ANALYSIS

This retrospective observational study included 62 individuals aged 4-17 years (mean±SD: 10.21±2.70) with progressing myopia but without ocular pathology with a range of -0.88 to -8.25 D spherical equivalent refraction (SER) (-3.73±1.56), coupled with astigmatism up to -3.25 D cylindrical. All participants were prescribed DIMS (Hoya MiyoSmart) spectacles. Key outcome variables were cycloplegic SER, measured for all participants and axial length (AL), assessed in a subset of patients, recorded at baseline, 6 months and 12 months. Quality of life assessments were conducted at baseline, at 2 weeks, and 3, 6, 9 and 12 months. Additionally, parental myopic dioptre was recorded when applicable.

RESULTS

At the 12-month mark, myopia progression in patients (mean±SE: -0.40±0.05) mirrored findings from prior European DIMS studies, but with 50% of patients showing no progression. A multivariate analysis of covariance model revealed that baseline astigmatism and younger age adversely affected therapy outcomes in both SER and AL, while severe maternal myopia led to greater SER progression. In contrast, only young age but not astigmatism was associated with AL increase in a comparable group of children with myopia, part of the LIFE Child Study, wearing single-vision spectacles. Patients reported consistent satisfaction with treatment, with minimal side effects, which diminished over the year.

CONCLUSION

In the European population, astigmatism, young age and severe maternal myopia are risk factors for suboptimal outcomes following DIMS therapy. Further research is necessary to elucidate the impact of astigmatism on myopic defocus therapy.

Effect of myopia-control lenses on central and peripheral visual performance in myopic children

PURPOSE

To evaluate the short-term effects of three myopia-control lenses, which impose peripheral myopic defocus while providing clear central vision, on central and peripheral visual performance in myopic children.

METHODS

Twenty-one myopic children were enrolled in the study. Central visual performance was assessed using the quick contrast sensitivity function. Peripheral visual performance was evaluated by measuring peripheral contrast threshold and global motion perception, while subjects maintained fixation through the central portion of the lens. Single-vision spectacle lenses (SVL), spectacle lenses with highly aspherical lenslets (HAL) and defocus-incorporated soft contact (DISC) lenses were evaluated in random order, followed by orthokeratology (OK) lenses. All tests were performed monocularly on the right eye.

RESULTS

The area under the log contrast sensitivity function (AULCSF) with DISC lenses was lower than that with SVL (1.14 vs. 1.40, p < 0.001) and HAL (1.14 vs. 1.33, p = 0.001). HAL increased the temporal visual field contrast threshold compared with OK lenses (p = 0.04), and OK lenses decreased the superior visual field contrast threshold compared with that of SVL (p = 0.04) and HAL (p = 0.005). HAL also increased the peripheral coherence threshold for identifying the contraction movement compared with OK lenses (p = 0.01).

CONCLUSIONS

The short-term use of these optical interventions for myopia control exhibited measurable differences in central and peripheral visual performance. Relevant attention could be paid to these differences, especially when children switch to different treatments. DISC lenses exhibited worse central contrast sensitivity than SVL and HAL. Imposing peripheral defocus signals did not affect children's peripheral visual performance compared with SVL. However, considering the poorer peripheral visual performance provided by HAL, OK lenses are recommended for children if there are specific demands for global scene recognition and motion perception.

Assessing the rebound phenomenon in different myopia control treatments: A systematic review

PURPOSE

To review the rebound effect after cessation of different myopia control treatments.

METHODS

A systematic review that included full-length randomised controlled studies (RCTs), as well as post-hoc analyses of RCTs reporting new findings on myopia control treatments rebound effect in two databases, PubMed and Web of Science, was performed according to the PRISMA statement. The search period was between 15 June 2023 and 30 June 2023. The Cochrane risk of bias tool was used to analyse the quality of the selected studies.

RESULTS

A total of 11 studies were included in this systematic review. Unifying the rebound effects of all myopia control treatments, the mean rebound effect for axial length (AL) and spherical equivalent refraction (SER) were 0.10 ± 0.07 mm [-0.02 to 0.22] and -0.27 ± 0.2 D [-0.71 to -0.03] after 10.2 ± 7.4 months of washout, respectively. In addition, spectacles with highly aspherical lenslets or defocus incorporated multiple segments technology, soft multifocal contact lenses and orthokeratology showed lower rebound effects compared with atropine and low-level light therapy, with a mean rebound effect for AL and SER of 0.04 ± 0.04 mm [0 to 0.08] and -0.13 ± 0.07 D [-0.05 to -0.2], respectively.

CONCLUSIONS

It appears that the different treatments for myopia control produce a rebound effect after their cessation. Specifically, optical treatments seem to produce less rebound effect than pharmacological or light therapies. However, more studies are required to confirm these results.

Myopia control: Seeing beyond efficacy

SIGNIFICANCE

The availability of a range of effective myopia control modalities enables the clinician to exercise judgment when discussing the treatment plan with the patient and their parents. This article outlines important considerations beyond efficacy.Clinically meaningful myopia control may be attained with some spectacle lenses, select soft contact lenses, some concentrations of atropine, and overnight orthokeratology. Given that satisfactory efficacy can be achieved with a range of modalities, other factors should be considered when deciding upon the best intervention for a given child. Four key factors-compliance, quality of vision, quality of life, and safety-are discussed in this review. Compliance directly impacts efficacy regardless of the modality and is the most important consideration, as it is influenced by quality of vision and comfort. Daily disposal myopia control contact lenses and overnight orthokeratology are generally associated with high compliance, provide better vision-related quality of life than spectacles, and carry a very low risk when used appropriately. A further benefit of overnight orthokeratology is the elimination of a need for optical correction during the day.

Repeatability and agreement of the MYAH and Lenstar

SIGNIFICANCE

Validation of new biometry instruments against the gold standard and establishing repeatability are important before being utilized for clinical and research applications.

PURPOSE

This study aimed to investigate intersession repeatability of the MYAH optical biometer and corneal topographer and examine agreement with the Lenstar LS900 optical biometer in healthy young adults.

METHODS

Forty participants (mean age, 25.2 ± 3.1 years) presented for two visits, 2 to 4 days apart. At each visit, measurements for right eyes were collected with the MYAH and Lenstar LS 900 and included axial length, corneal power, white-to-white distance, and pupil diameter. Bland-Altman analysis was used to assess the intrasession agreement between the MYAH and Lenstar for each parameter and intersession repeatability for the two devices. For each device, coefficient of variation and intraclass correlation coefficient were calculated, and paired t tests between visits were performed to assess intersession repeatability.

RESULTS

Good agreement (mean difference [95% limits of agreement]) between the MYAH and Lenstar was found for axial length (-0.01 [-0.07 to 0.04] mm), corneal power (-0.02 D [-0.15 to 0.19 d]), white-to-white distance (-0.13 [-0.43 to 0.17] mm), and pupil diameter (-0.27 [-0.79 to 1.33] mm). The limits of agreement, coefficient of variations, and intraclass correlation coefficients for MYAH-measured parameters were -0.04 to 0.04, 0.06%, and >0.99 for axial length; -0.24 to 0.19, 0.18%, and >0.99 for corneal power; -1.05 to 1.15, 0.57%, and 0.96 for white-to-white distance; and -0.17 to 0.21, 7.0%, and 0.76 for pupil diameter, with no significant difference between visits (p>0.05 for all), indicating good intersession repeatability. Similar intersession repeatability was also noted for Lenstar.

CONCLUSIONS

Findings show good intersession repeatability of the MYAH and good agreement with the Lenstar for axial length, corneal power, and white-to-white distance in young adults. Pupil diameter was more variable, likely due to the dynamic nature of the pupil. This study provides validation and supports the use of the MYAH for ocular biometry.

New Designs of Spectacle Lenses for the Control of Myopia Progression: A Scoping Review

Myopia control with new designs of spectacle lenses is a flourishing area of research. The present work reviews the effectiveness of new designs (DIMSs, defocus-incorporated multiple segments; CARE, cylindrical annular refractive element; HALs/SALs, highly/slightly aspherical lenslets; DOT, diffusion optics technology) aiming at slowing myopia progression. A search through the PubMed database was conducted for articles published between 1 January 2003 and 28 February 2023. Publications were included if they documented baseline central refraction (SER) and/or axial length (AL) data, and the change in these parameters, in myopic children wearing new designs of spectacle lenses (treatment group) compared to myopic children using single-vision lenses, SVLs (control group). The selection process revealed nine suitable articles. Comparing the mean and standard error values of the treatment and control groups, the highest differences in the change in the SER and AL were -0.80 (1.23) D [95% CI: -1.053 to -0.547; p < 0.001] and 0.35 (0.05) mm [95% CI: 0.252 to 0.448; p < 0.001], respectively; the effect of treatment provided by a HAL design, compared to SVLs, led to a deceleration of 54.8% in the SER and 50.7% in the AL. However, the heterogeneity of the results prevents reaching strong conclusions about the effectiveness of these new designs.

Orthokeratology combined with spectacles in moderate to high myopia adolescents

PURPOSE

Wearing ortho-k lenses overnight may not fully correct their daytime refractory errors of adolescents with moderate to high myopia. There are three common ways to deal with the daytime residual refractive error (RRE): 1) wearing spectacles to correct the RRE; 2) wear ortho-k lenses during the daytime instead of overnight.; 3) not correcting the residual refractive error. According to previous laboratory studies, myopic peripheral refraction is associated with better myopic control. This study had two aims:1) to compare relative peripheral refractive error (RPRE) among these ways after one-month stabilization; 2) to assess the axial length changes over 2 years of ortho-k lens overnight wear combined with spectacle glasses.

METHODS

This was a prospective, non-controlled, non-randomized, observational study in which a total of 27 subjects (20 females, 7 males, mean age 12.48 ± 2.23Y) with spherical equivalent refractive error from -5.00 to -8.25D were enrolled. All participants in the study wore orthokeratology (ortho-k) lenses overnight for a minimum of one month. Subsequently, their peripheral refractive error (PRE) was assessed using an open-field autorefractor. During the assessment, the participants underwent three conditions in a random order in a same morning: 1) unaided eye after orthokeratology (referred to as the Unaided-eye condition), 2) wearing glasses to correct any remaining refractive errors after orthokeratology (referred to as the Spec-RE condition), and 3) wearing ortho-k lenses during the daytime (referred to as the Continuous OK wear condition). After testing, all subjects were instructed to wear ortho-k lenses overnight and glasses during the daytime to correct their RRE for the next 2 years, during which time the progression of their axial length was followed up.

RESULTS

1) RPRE in either Unaided-eye or Spec-RE condition subjects were significantly more myopic than those in the Continuous OK wear condition. 2) No difference in RPRE was seen between Unaided-eye and Spec-RE conditions. 3) Axial length growth was 0.05 ± 0.20 mm and 0.17 ± 0.32 mm (mean ± standard deviation) at 1-year and 2-year follow-ups after the initial visit, respectively, which were comparable to mild myopia patients after orthokeratology. 4) After orthokeratology, axial length change had negative correlation with the initial age (p = 0.001, r = -0.616) and residual diopter (p = 0.022).

CONCLUSIONS

For myopes above refraction < -5.00D, wearing Ortho-k lenses overnight and glasses to correct the RRE in the daytime is recommended to ensure good visual quality and have more myopic RPRE for potential myopia control.

Optical interventions for myopia control

A range of optical interventions have been developed to slow the progression of myopia. This review summarizes key studies and their outcomes. Peer-reviewed, randomized controlled clinical trials of at least 18 months duration were identified. Randomized clinical trials were identified and summarised: 13 for spectacles, 5 for overnight orthokeratology, 5 for soft contact lenses, and 3 for orthokeratology combined with low concentration atropine. Overnight orthokeratology trials were the most consistent with 2-year slowing of axial elongation between 0.24 and 0.32 mm. Other modalities were more variable due to the wide range of optical designs. Among spectacle interventions, progressive addition lenses were the least effective, slowing axial elongation and myopia progression by no more than 0.11 mm and 0.31 D, respectively. In contrast, novel designs with peripheral lenslets slow 2-year elongation and progression by up to 0.35 mm and 0.80 D. Among soft contact lens interventions, medium add concentric bifocals slow 3-year elongation and progression by only 0.07 mm and 0.16 D, while a dual-focus design slows 3-year elongation and progression by 0.28 mm and 0.67 D. In summary, all three optical interventions have the potential to significantly slow myopia progression. Quality of vision is largely unaffected, and safety is satisfactory. Areas of uncertainty include the potential for post-treatment acceleration of progression and the benefit of adding atropine to optical interventions.

Effectiveness of a Spectacle Lens with a Specific Asymmetric Myopic Peripheral Defocus: 12-Month Results in a Spanish Population

BACKGROUND

Different designs of ophthalmic lenses have been studied to control the progression of myopia in children. This study aims to evaluate the short-term efficacy of a new design of ophthalmic lens with asymmetric myopic peripheral defocus (MPDL) on myopia progression in children compared to a control group wearing a single-vision lens (SVL).

METHODS

Children aged 5 to 12 with myopia up to -0.50 D, astigmatism and anisometropia under 1.50 D, and corrected visual acuity over 20/20 were randomized to either the study group (MPDL) or control group (SVL). The myopia progression was evaluated by measuring axial length (AL) growth (IOL Master; Zeiss) over a period of one year.

RESULTS

Ninety-two subjects were recruited. Forty-six children were randomly assigned to the control group, and 46 to the study group. In total, 83 children completed the clinical trial, with a mean age of 10.81 [9.53-11.92] years, among which 59.04% were female. After one year of treatment, there was less AL elongation in the study group compared to the control group (0.16 ± 0.16 mm vs. 0.24 ± 0.16 mm, p = 0.034).

CONCLUSIONS

The MPDL significantly reduced the absolute growth of AL by 39% (p = 0.014) and relative growth of AL by 37.3% (p = 0.012) after 12 months in comparison to the control group in a Spanish population.

Juvenile-onset myopia-who to treat and how to evaluate success

The risk of eye diseases such as myopic macular degeneration increases with the level of myopia, but there is no safe level of myopia and the burden of lower degrees of myopia remains considerable. Effective treatments are available that slow progression and thus limit the final degree of myopia. In this review, the rationale for slowing progression is summarized, and a case made for treating all myopic children. Measurement of refractive error and axial length is reviewed, stressing the precision of optical biometry, but also the need for cycloplegic autorefraction. The factors influencing progression are considered and the available tools for interpretation of progression rate are discussed. Finally, the need to set attainable treatment goals is emphasized.

Evaluating the Effect of a Myopia Control Spectacle Lens Among Children in Israel: 12-Month Results

PURPOSE

To investigate the effectiveness of a novel spectacle lens designed to slow the progression of myopia in children.

DESIGN

A prospective, randomized, double blind clinical trial.

METHODS

One hundred twenty-six Israeli children aged 6-13 years with spherical equivalent (SER) refractive errors of -0.5 to -6.25 diopters (D) were randomized into either the Shamir Myopia Control (SMC) lens design group or the conventional single-vision spectacle lenses (SVL), the control group. Outcomes measured were changes in axial length and cycloplegic refraction as well as subjective rating of visual experience over a period of 12 months.

RESULTS

At 12 months, AL and SER progression were slowed by 0.11 mm (35%, P < .05) and 0.16 D (25%, P = .122), respectively. In the subgroup of 6-10-year-olds, AL and SER progression were slowed by 0.17 mm (41%, P < .05) and 0.31 D (43%, P < .05), respectively. Similarly, for the subgroup of children with 2 myopic parents AL and SER progression were slowed by 0.15 mm (45% P < .05) and 0.36 D (42%, P < .05), respectively. Subjective visual experience reported in the 12-month questionnaire revealed no difference between the SMC and SVL groups, and average daily wearing hours were also not different between the groups: 14 (±1.4) and 13.8 (±2.3) hours, respectively. The study continues to its second year.

CONCLUSIONS

SMC lenses were effective in slowing the progression of SER and AL, especially for younger children and those having 2 myopic parents. The subjective rating of visual experience and the daily duration of use reported by the SMC group at 12 months were similar to the control group, indicating good lens tolerability.

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

PURPOSE

To compare the efficacy and safety of low-level red light (LRL) in controlling myopia progression at 3 different powers: 0.37 mW, 0.60 mW, and 1.20 mW.

DESIGN

Single-center, single-masked, randomized controlled trial.

PARTICIPANTS

Two hundred children aged 6-15 with myopia of -0.50 diopter (D) or more and astigmatism of -2.50 D or less were enrolled from April to May 2022. Follow-up ended in December 2022.

METHODS

Participants were assigned randomly to 3 intervention groups and 1 control group (1:1:1:1). All participants wore single-vision spectacles. Moreover, the intervention group randomly received LRL at 3 different powers twice daily for 3 minutes per session, with a minimum 4-hour interval.

MAIN OUTCOME MEASURES

Changes in spherical equivalent (SE), axial length (AL), and subfoveal choroidal thickness (SFCT) were measured.

RESULTS

After 6 months, SE progression was significantly lower in the 0.37-mW group (0.01 D; 95% confidence interval [CI], -0.12 to 0.15), 0.60-mW group (-0.05 D; 95% CI, -0.18 to 0.07), and 1.20-mW group (0.16 D; 95% CI, 0.03 to 0.30) compared to the control group (-0.22 D; 95% CI, -0.50 to 0.30; adjusted P < 0.001 for all). AL changes in the 0.37-mW group (0.04 mm; 95% CI, -0.01 to 0.08), 0.60-mW group (0.00 mm; 95% CI, -0.05 to 0.05), and 1.20-mW group (-0.04 mm; 95% CI, -0.08 to 0.01) were significantly smaller than the control group (0.27 mm; 95% CI, 0.22 to 0.33; adjusted P < 0.001 for all). Similarly, increases in SFCT were significantly greater in the 0.37-mW group (22.63 μm; 95% CI, 12.13 to 33.34 μm), 0.60-mW group (36.17 μm; 95% CI, 24.37 to 48.25 μm), and 1.20-mW group (42.59 μm; 95% CI, 23.43 to 66.24 μm) than the control group (-5.07 μm; 95% CI, -10.32 to -0.13 μm; adjusted P < 0.001 for all). No adverse events were observed.

CONCLUSIONS

LRL effectively controlled myopia progression at 0.37 mW, 0.60 mW, and 1.20 mW. Further research is required.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Eye growth pattern of myopic children wearing spectacle lenses with aspherical lenslets compared with non-myopic children

INTRODUCTION

To evaluate eye growth of children wearing spectacle lenses with highly aspherical lenslets (HAL), slightly aspherical lenslets (SAL) and single-vision lenses (SVL) compared to eye growth patterns in non-myopes in Wenzhou, China.

METHODS

The randomised trial had 170 myopic children (aged 8-13 years) randomly assigned to the HAL, SAL or SVL group. Normal eye growth was examined using 700 non-myopic schoolchildren (aged 7-9 years) in the Wenzhou Medical University-Essilor Progression and Onset of Myopia (WEPrOM) cohort study using logistic function models. Slow, normal and fast eye growth was defined as range of values <25th, 25th-75th and >75th percentiles, respectively.

RESULTS

The predicted upper limits of slow eye growth (25th percentile) among non-myopes aged 7-10 years and 11-13 years were 0.20-0.13 and 0.08-0.01 mm (after 2-year period; 0.37-0.33 and 0.29-0.14 mm), respectively, while the upper limits of normal eye growth (75th percentile) were 0.32-0.31 and 0.28-0.10 mm (after 2-year period; 0.58-0.55 and 0.50-0.24 mm), respectively. The 2-year trial had 157 children, 96 of whom wore their lenses full time (everyday ≥12 h/day). The mean 2-year axial length change for HAL, SAL and SVL was 0.34, 0.51 and 0.69 mm (0.28, 0.46 and 0.69 mm in full-time wear), respectively. Slow eye growth was found in 35%, 17% and 2% (44%, 29% and 3% in full-time wear); normal eye growth in 35%, 26% and 12% (44%, 32% and 9% in full-time wear) and fast eye growth in 30%, 57% and 86% (12%, 39% and 88% in full-time wear), respectively (p < 0.001).

CONCLUSIONS

The eye growth pattern in approximately 90% wearing HAL full time (compared with about 10% wearing SVL full time) was similar or slower than that of non-myopic children both after 1- and 2-year periods.

Myopia management algorithm. Annexe to the article titled Update and guidance on management of myopia. European Society of Ophthalmology in cooperation with International Myopia Institute

Myopia is becoming increasingly common in young generations all over the world, and it is predicted to become the most common cause of blindness and visual impairment in later life in the near future. Because myopia can cause serious complications and vision loss, it is critical to create and prescribe effective myopia treatment solutions that can help prevent or delay the onset and progression of myopia. The scientific understanding of myopia's causes, genetic background, environmental conditions, and various management techniques, including therapies to prevent or postpone its development and slow its progression, is rapidly expanding. However, some significant information gaps exist on this subject, making it difficult to develop an effective intervention plan. As with the creation of this present algorithm, a compromise is to work on best practices and reach consensus among a wide number of specialists. The quick rise in information regarding myopia management may be difficult for the busy eye care provider, but it necessitates a continuing need to evaluate new research and implement it into daily practice. To assist eye care providers in developing these strategies, an algorithm has been proposed that covers all aspects of myopia mitigation and management. The algorithm aims to provide practical assistance in choosing and developing an effective myopia management strategy tailored to the individual child. It incorporates the latest research findings and covers a wide range of modalities, from primary, secondary, and tertiary myopia prevention to interventions that reduce the progression of myopia.

Repeated Low-level Red-light Therapy: The Next Wave in Myopia Management?

SIGNIFICANCE

Exposure to long-wavelength light has been proposed as a potential intervention to slow myopia progression in children. This article provides an evidence-based review of the safety and myopia control efficacy of red light and discusses the potential mechanisms by which red light may work to slow childhood myopia progression.The spectral composition of the ambient light in the visual environment has powerful effects on eye growth and refractive development. Studies in mammalian and primate animal models (macaque monkeys and tree shrews) have shown that daily exposure to long-wavelength (red or amber) light promotes slower eye growth and hyperopia development and inhibits myopia induced by form deprivation or minus lens wear. Consistent with these results, several recent randomized controlled clinical trials in Chinese children have demonstrated that exposure to red light for 3 minutes twice a day significantly reduces myopia progression and axial elongation. These findings have collectively provided strong evidence for the potential of using red light as a myopia control intervention in clinical practice. However, several questions remain unanswered. In this article, we review the current evidence on the safety and efficacy of red light as a myopia control intervention, describe potential mechanisms, and discuss some key unresolved issues that require consideration before red light can be broadly translated into myopia control in children.

Efficiency and Related Factors of Multifocal Soft Contact Lenses in Controlling Myopia

OBJECTIVE

To evaluate ocular changes in Chinese myopic children wearing multifocal soft contact lenses and explore their efficiency and related factors.

METHOD

This was a prospective, double-blind, randomized controlled study. A total of 36 myopic children aged 7 to 12 years were randomly divided into groups wearing multifocal soft contact lenses (MFCLs) or single-vision soft contact lenses (SVCLs) and followed up for 12 months. The spherical equivalent (SE), axial length (AL), choroidal thickness, and vascularity were measured before commencement and after 6 and 12 months of lens wear. Correlation between ocular changes and myopia progression was determined.

RESULTS

A total of 32 subjects (6 males and 26 females) completed the study and were included in the analysis. After 12 months of lens wear, both the AL elongation (0.25±0.22 vs. 0.43±0.16 mm, P=0.011) and the SE progression (-0.69±0.69 D vs. -1.45±0.56 D, P=0.002) of the MFCL group were significantly lower than those of the SVCL group. After 12 months, the progression of myopia was significantly correlated with changes of the choroid in the MFCL wearers, whereas no such correlation was observed in the SVCL group.

CONCLUSION

Multifocal soft contact lens can slow myopia progression, and this effect may be related to the changes of the choroid.

Age-matched analysis of axial length growth in myopic children wearing defocus incorporated multiple segments spectacle lenses

BACKGROUND/AIMS

Defocus incorporated multiple segments (DIMS) spectacle lenses are known to be able to inhibit axial length (AL) growth in myopic children compared with single vision (SV) spectacle lenses. However, it is not known whether AL growth is sufficiently inhibited to achieve the treatment goal of physiological AL growth.

METHODS

Of the data already collected in 2014-2017 by Lam et al, the AL growth with DIMS and SV spectacle lenses was re-evaluated according to the age-matched myopia control system. The individual AL growth after the first year of treatment of each eye was plotted against the corresponding age of the same time point in a colour-coded scheme. The two treatment groups were further subdivided based on their age and their baseline AL.

RESULTS

Overall, 65% (61% of male, 70% of female) of eyes with DIMS spectacle lenses and 16% (16% of male, 16% of female) of eyes with SV spectacle lenses are within range of physiological AL growth rate. Median AL growth rate of eyes with DIMS spectacle lenses is also within the range of physiological growth. In the subgroups, eyes with DIMS spectacle lenses were also superior to the ones with SV spectacle lenses regarding this treatment goal. Of the children with SV spectacle lenses, older children and children with eyes with high baseline AL were least likely to achieve physiological AL growth rate.

CONCLUSIONS

DIMS spectacle lenses can bring the AL growth rate of myopic children to the level of physiological AL growth rate, indicating 100% reduction of excessive myopic AL growth, independent of age and baseline AL. Older children and children with eyes with high AL have the risk to have increased AL growth without treatment.

Effect of spectacle lenses with aspherical lenslets on choroidal thickness in myopic children: a 2-year randomised clinical trial

OBJECTIVE

Spectacle lenses with highly aspherical lenslets (HAL) and slightly aspherical lenslets (SAL) showed effective myopia control. This study was to investigate their effects on macular choroidal thickness (ChT) in myopic children.

METHODS

Exploratory analysis from a 2-year, double-masked, randomised trial. 170 children aged 8-13 years with myopia between -0.75D and -4.75D, astigmatism of 1.50D or less, and anisometropia of 1.00D or less were recruited. Participants were randomly assigned in a 1:1:1 ratio to receive HAL, SAL or single vision spectacle lenses (SVL). The subfoveal, parafoveal and perifoveal ChT were evaluated every 6 months.

RESULTS

154 participants completed all examinations. The ChT showed significant changes over time in all three groups in all regions (all p<0.05). The ChTs continuously decreased in the SVL group (ranging from -20.75 (SD 22.34) μm to -12.18 (22.57) μm after 2 years in different regions). Compared with the SVL group, ChT in the SAL group decreased less (ranging from -16.49 (21.27) μm to -5.29 (18.15) μm). In the HAL group, ChT increased in the first year and then decreased in the second year (ranging from -0.30 (27.54) μm to 8.92 (23.97) μm after two years). The perifoveal ChT decreased less than the parafoveal ChT, and the superior region decreased the least.

CONCLUSIONS

The ChT of the macula decreased after 2 years of myopia progression with SVL. Wearing spectacle lenses with aspherical lenslets reduced or abolished the ChT thinning and HAL had a more pronounced effect.

TRIAL REGISTRATION NUMBER

ChiCTR1800017683.

Temporal effects of an original myopia song on school children's myopia and awareness: a 3-year prospective study

CLINICAL RELEVANCE

Raising children's myopia prevention awareness and behaviour tends to exhibits a protective effect against myopia among schoolchildren.

BACKGROUND

To investigate the effect of an original myopia song in raising school children's awareness of healthier eye use behaviour and on myopia prevention.

METHODS

In this prospective randomised control study, two groups of students from one primary schools in Jiangxi, China, were enrolled and monitored from grade 3 to grade 6 (2016-2019). The primary outcome was the change in axial length (AL) after the intervention. Secondary outcomes included changes in spherical equivalent refraction (SER), near work and outdoor time, corrected near and distant visual acuity, visual discomfort score (VDS) and accommodative lag.

RESULTS

Four hundred students (193 females, 48.25%) aged 9.3 (range 8-10) years with emmetropia to moderate myopia were enrolled. Children in the myopia song group had a significantly shorter AL and less myopic refractive change than those in the control group (p = 0.04 and 0.02, respectively). Compared with the control group, children in the myopia song group spent less time on near work and more time outdoors (p = 0.04 and 0.04, respectively). At the final follow-up, the proportion of children with myopia was significantly lower in the myopia song group (30.5%) than in the control group (41%) (p = 0.03). No significant differences were found for the secondary outcomes, including corrected near and distant visual acuity, VDS and accommodative lag.

CONCLUSIONS

An original myopia song performed twice daily in primary schools appeared to have a modest effect on myopia control among school-aged children by changing their lifestyles in the long term.

Predicting the child who will become myopic - can we prevent onset?

Myopia has become a global epidemic with significant public health impacts. Identifying the child at risk of developing myopia, i.e. the pre-myopic child and implementing strategies to prevent the onset of myopia, could significantly reduce the burden of myopia on an individual and society. This paper is a review of publications that have identified ocular characteristics of children at risk of future myopia development including a lower than age normal amount of hyperopia and accelerated axial length elongation. Risk factors associated with increased risk of myopia development such as education exposure and reduced outdoor time, and strategies that could be implemented to prevent myopia onset in children are also explored. The strong causal role of education and outdoor time on myopia development suggests that lifestyle modifications could be implemented as preventative measures to at-risk children and may significantly impact the myopia epidemic by preventing or delaying myopia onset and its associated ocular health consequences.

A Comparison of Optical Biometers Used in Children for Myopia Control

PURPOSE

To assess the reproducibility (i.e., inter-device reliability) of the biometers Topcon MYAH, Oculus Myopia Master, and Haag-Streit Lenstar LS900 with the Carl Zeiss IOLMaster 700 and the intra-subject repeatability in myopic children in order to reliably detect axial growth for myopia management.

METHODS

Twenty-two myopic children (11.1 ± 2.4 yr) with a spherical equivalent of - 3.53 ± 2.35 D were examined with each of the biometers to assess axial length (AL) and corneal parameters (steepK, flatK, meanK, vectors J0, J45), and16 of these children agreed to a second round of measurements. Reproducibility of the first measurements between the IOLMaster and every other biometer was assessed employing a Bland-Altman approach and paired Student's t-test. Repeatability was assessed as intra-subject standard deviation and was used to estimate the minimum time interval required between two AL measurements to reliably detect axial growth of an eye of at least 0.1 mm/year.

RESULTS

Repeatability for AL measurements was as follows: IOLMaster: 0.05 mm, Myopia Master: 0.06 mm, Myah: 0.06 mm, Lenstar: 0.04 mm; the respective minimal time interval for axial growth assessment in myopia management was estimated as 5.6, 6.6, 6.7, and 5.0 months, respectively. Best reproducibility of the AL measurement was found between IOLMaster and Lenstar [95% Limits of Agreement (LoA) for reproducibility - 0.06 to 0.02]. As regards to the measured means, Lenstar gave measures of AL that were longer than with the IOLMaster by 0.02 mm (p < 0.001). Myopia Master measures of meanK were significantly lower (by 0.21 D with p < 0.001) than the values from the IOLMaster. As for J0, all biometers deviated significantly from IOLMaster measurements (p < 0.05).

CONCLUSION

Generally good agreement was observed between all the biometers. When assessing myopia progression in children, a time frame of at least 6 months between the AL measurements is advisable in order to reliably determine any deviation from a normal growth pattern.

Myopia prevention and control in children: a systematic review and network meta-analysis

OBJECTIVES

To analyse and compare the efficacy of different interventions for myopia prevention and control in children.

METHODS

We searched CNKI, VIP, Wan-Fang, CBM, Chinese Clinical Registry, PubMed, The Cochrane Library, Web of Science, Embase and ClinicalTrials.gov from inception to July 2022. We selected randomized controlled trials (RCTs) that included interventions to slow myopia progression in children. The main outcomes included mean annual change in axial length (AL) (millimetres/year) and in refraction (R) (dioptres/year).

RESULTS

A total of 80 RCTs (27103 eyes) were included. In comparison with control, orthokeratology (AL, -0.36 [-0.53, -0.20], P < 0.05; R, 0.56 [0.34, 0.77], P < 0.05), 1%Atropine (AL, -0.39 [-0.65, -0.13], P < 0.05; R, 0.54 [0.31, 0.77], P < 0.05), 0.01%Atropine + orthokeratology (AL, -0.47 [-0.80, -0.14], P < 0.05; R, 0.81 [0.43, 1.20], P < 0.05) could significantly slow the progression of myopia; in addition, progressive multi-focal spectacle lenses (PMSL) (0.42, [0.06, 0.79], P < 0.05), bifocal soft contact lenses (0.40, [0.03, 0.77], P < 0.05), 0.5%Atropine (0.67 [0.25, 1.10], P < 0.05), 0.1%Atropine (0.42 [0.15, 0.71], P < 0.05), 0.05%Atropine (0.57 [0.28, 0.86], P < 0.05), 0.01%Atropine (0.33 [0.15, 0.52], P < 0.05), 1%Atropine + bifocal spectacle lenses (BSL) (1.30 [0.54, 2.00], P < 0.05), 1%Atropine + PMSL (0.66 [0.23, 1.10], P < 0.05), 0.01%Atropine + single vision spectacle lenses (SVSL) (0.70 [0.23, 1.10], P < 0.05), 0.01%Atropine + orthokeratology (0.81 [0.43, 1.20], P < 0.05), BSL + Massage (0.85 [0.22, 1.50], P < 0.05), SVSL + Red light (0.59 [0.06, 0.79], P < 0.05) showed significant slowing effect on the increase in R.

CONCLUSIONS

This network meta-analysis suggests that the combined measures were most effective in AL and R, followed by Atropine.

Peripheral Defocus, Pupil Size, and Axial Eye Growth in Children Wearing Soft Multifocal Contact Lenses in the BLINK Study

Purpose

The purpose of this study was to evaluate the relationship between peripheral defocus and pupil size on axial growth in children randomly assigned to wear either single vision contact lenses, +1.50 diopter (D), or +2.50 D addition multifocal contact lenses (MFCLs).

Methods

Children 7 to 11 years old with myopia (-0.75 to -5.00 D; spherical component) and ≤1.00 D astigmatism were enrolled. Autorefraction (horizontal meridian; right eye) was measured annually wearing contact lenses centrally and ±20 degrees, ±30 degrees, and ±40 degrees from the line of sight at near and distance. Photopic and mesopic pupil size were measured. The effects of peripheral defocus, treatment group, and pupil size on the 3-year change in axial length were modeled using multiple variables that evaluated defocus across the retina.

Results

Although several peripheral defocus variables were associated with slower axial growth with MFCLs, they were either no longer significant or not meaningfully associated with eye growth after the treatment group was included in the model. The treatment group assignment better explained the slower eye growth with +2.50 MFCLs than peripheral defocus. Photopic and mesopic pupil size did not modify eye growth with the +2.50 MFCL (all P ≥ 0.37).

Conclusions

The optical signal causing slower axial elongation with +2.50 MFCLs is better explained by the lens type worn than by peripheral defocus. The signal might be something other than peripheral defocus, or there is not a linear dose-response relationship within treatment groups. We found no evidence to support pupil size as a criterion when deciding which myopic children to treat with MFCLs.

Effects of Spectacle Lenses With Aspherical Lenslets on Peripheral Eye Length and Peripheral Refraction in Myopic Children: A 2-Year Randomized Clinical Trial

Purpose

To investigate changes in peripheral eye length (PEL) and peripheral refraction (PR) in myopic children after wearing spectacle lenses with highly or slightly aspherical lenslets (HAL or SAL) for 2 years.

Methods

We recruited 170 children aged 8 to 13 years with myopia between -0.75 diopters (D) and -4.75 D. Participants were randomized to wear HAL, SAL, or single vision spectacle lenses (SVL). PEL and PR were measured at 0° central and 15° and 30° in the nasal and temporal retina every 6 months for 2 years. The relative PR (RPR) was calculated by subtracting central from peripheral values.

Results

PELs significantly increased with time (all P < 0.001), with the greatest elongation in the SVL group and the least in the HAL group. In the SVL and SAL groups, axial length elongated faster than the periphery. Whereas in the HAL group, N30 elongated faster than other PELs, axial length elongated less than the periphery. With time, the PR became more negative (all P < 0.001), with the most negative changes in the SVL group and the least negative changes in the HAL group. RPR became more hyperopic in the SVL and SAL groups, but less hyperopic in the HAL group (all P < 0.001).

Conclusions

Over the 2-year myopia progression, steeper retina and greater peripheral hyperopic defocus were found in the SVL group. In the SAL group, changes were attenuated. In the HAL group, the retina flattened and peripheral defocus became less hyperopic.

Translational Relevance

HAL and SAL lenses had little impact on PEL elongation.

Efficacy of the Euclid orthokeratology lens in slowing axial elongation

PURPOSE

The Euclid Emerald lens designs for orthokeratology have been available in global markets for over 20 years and is used extensively by clinicians for slowing myopia progression in children. This paper comprehensively reviews data from published studies of the efficacy of this lens.

METHODS

A comprehensive systematic search was performed in March 2023 using Medline with the following search terms: orthokeratology AND myopi* AND (axial or elong*) NOT (review or meta).

RESULTS

The original search identified 189 articles, of which 140 reported axial elongation. Of those, 49 reported data on the Euclid Emerald design. Unique axial elongation data could be extracted from 37 papers-14 of which included an untreated control group. Among these, the mean 12-month efficacy-the difference in axial elongation between orthokeratology wearers and controls-was 0.18 mm (range: 0.05-0.29 mm), and the mean 24-month efficacy was 0.28 mm (range: 0.17-0.38 mm). The orthokeratology wearers in 23 studies without an untreated comparison group showed similar axial elongation to those in the 14 studies with a control group. For example, the mean 12-month axial elongation for the studies with controls was 0.20 ± 0.06 mm compared with 0.20 ± 0.07 mm for the studies without controls.

CONCLUSIONS

This extensive body of literature on a single device for myopia control is unique and demonstrates the efficacy of this design in slowing axial elongation in myopic children.

Efficacy and Safety of 0.01% and 0.02% Atropine for the Treatment of Pediatric Myopia Progression Over 3 Years: A Randomized Clinical Trial

Importance

The global prevalence of myopia is predicted to approach 50% by 2050, increasing the risk of visual impairment later in life. No pharmacologic therapy is approved for treating childhood myopia progression.

Objective

To assess the safety and efficacy of NVK002 (Vyluma), a novel, preservative-free, 0.01% and 0.02% low-dose atropine formulation for treating myopia progression.

Design, Setting, and Participants

This was a double-masked, placebo-controlled, parallel-group, randomized phase 3 clinical trial conducted from November 20, 2017, through August 22, 2022, of placebo vs low-dose atropine, 0.01% and 0.02% (2:2:3 ratio). Participants were recruited from 26 clinical sites in North America and 5 countries in Europe. Enrolled participants were 3 to 16 years of age with -0.50 diopter (D) to -6.00 D spherical equivalent refractive error (SER) and no worse than -1.50 D astigmatism.

Interventions

Once-daily placebo, low-dose atropine, 0.01%, or low-dose atropine, 0.02%, eye drops for 36 months.

Main Outcomes and Measures

The primary, prespecified end point was the proportion of participants' eyes responding to 0.02% atropine vs placebo therapy (<0.50 D myopia progression at 36 months [responder analysis]). Secondary efficacy end points included responder analysis for atropine, 0.01%, and mean change from baseline in SER and axial length at month 36 in a modified intention-to-treat population (mITT; participants 6-10 years of age at baseline). Safety measurements for treated participants (3-16 years of age) were reported.

Results

A total of 576 participants were randomly assigned to treatment groups. Of these, 573 participants (99.5%; mean [SD] age, 8.9 [2.0] years; 315 female [54.7%]) received trial treatment (3 participants who were randomized did not receive trial drug) and were included in the safety set. The 489 participants (84.9%) who were 6 to 10 years of age at randomization composed the mITT set. At month 36, compared with placebo, low-dose atropine, 0.02%, did not significantly increase the responder proportion (odds ratio [OR], 1.77; 95% CI, 0.50-6.26; P = .37) or slow mean SER progression (least squares mean [LSM] difference, 0.10 D; 95% CI, -0.02 D to 0.22 D; P = .10) but did slow mean axial elongation (LSM difference, -0.08 mm; 95% CI, -0.13 mm to -0.02 mm; P = .005); however, at month 36, compared with placebo, low-dose atropine, 0.01%, significantly increased the responder proportion (OR, 4.54; 95% CI, 1.15-17.97; P = .03), slowed mean SER progression (LSM difference, 0.24 D; 95% CI, 0.11 D-0.37 D; P < .001), and slowed axial elongation (LSM difference, -0.13 mm; 95% CI, -0.19 mm to -0.07 mm; P < .001). There were no serious ocular adverse events and few serious nonocular events; none was judged as associated with atropine.

Conclusions and Relevance

This randomized clinical trial found that 0.02% atropine did not significantly increase the proportion of participants' eyes responding to therapy but suggested efficacy for 0.01% atropine across all 3 main end points compared with placebo. The efficacy and safety observed suggest that low-dose atropine may provide a treatment option for childhood myopia progression.

Trial Registration

ClinicalTrials.gov Identifier: NCT03350620.

Chinese Parents' Perspective on Myopia: A Cross-Sectional Survey Study

INTRODUCTION

The prevalence of myopia in young generations has dramatically increased over the years, especially in China. This study aims to understand Chinese parents' perspectives on myopia for further improvement of treatment compliance and informing future health planning and policy.

METHODS

This was a prospective cross-sectional survey study. A self-administrated, internet-based questionnaire was distributed to 2545 parents in China. Detailed information about the demographics, the awareness of myopia, related complications, and practices of myopia prevention and control of the respondents were collected. The distribution of answers was compared among different groups of children's age, children's refractions, and parents' residential locations. Relationships between parental cognition and behavior were also analyzed.

RESULTS

Eligible responses were returned by 2500 parents. A total of 55.1% of the respondents considered myopia as a disease and more than 70% of respondents did not realize pathological changes related to myopia. Most parents thought myopia could be prevented (82.0%) and controlled (75.2%), and these parents were more likely to take measures than the parents who did not think so (P < 0.001). The most common myopia control modality was spectacles (87.0%), among which single-vision spectacles are the most used (63.7%).

CONCLUSIONS

Knowledge about health risks related to myopia was lacking in Chinese parents and their practices of myopia control mainly involved single-vision glasses. Nationwide education for parents about myopia is needed to further advance outcomes of myopia prevention and control.

Benchmarking large language models' performances for myopia care: a comparative analysis of ChatGPT-3.5, ChatGPT-4.0, and Google Bard

BACKGROUND

Large language models (LLMs) are garnering wide interest due to their human-like and contextually relevant responses. However, LLMs' accuracy across specific medical domains has yet been thoroughly evaluated. Myopia is a frequent topic which patients and parents commonly seek information online. Our study evaluated the performance of three LLMs namely ChatGPT-3.5, ChatGPT-4.0, and Google Bard, in delivering accurate responses to common myopia-related queries.

METHODS

We curated thirty-one commonly asked myopia care-related questions, which were categorised into six domains-pathogenesis, risk factors, clinical presentation, diagnosis, treatment and prevention, and prognosis. Each question was posed to the LLMs, and their responses were independently graded by three consultant-level paediatric ophthalmologists on a three-point accuracy scale (poor, borderline, good). A majority consensus approach was used to determine the final rating for each response. 'Good' rated responses were further evaluated for comprehensiveness on a five-point scale. Conversely, 'poor' rated responses were further prompted for self-correction and then re-evaluated for accuracy.

FINDINGS

ChatGPT-4.0 demonstrated superior accuracy, with 80.6% of responses rated as 'good', compared to 61.3% in ChatGPT-3.5 and 54.8% in Google Bard (Pearson's chi-squared test, all p ≤ 0.009). All three LLM-Chatbots showed high mean comprehensiveness scores (Google Bard: 4.35; ChatGPT-4.0: 4.23; ChatGPT-3.5: 4.11, out of a maximum score of 5). All LLM-Chatbots also demonstrated substantial self-correction capabilities: 66.7% (2 in 3) of ChatGPT-4.0's, 40% (2 in 5) of ChatGPT-3.5's, and 60% (3 in 5) of Google Bard's responses improved after self-correction. The LLM-Chatbots performed consistently across domains, except for 'treatment and prevention'. However, ChatGPT-4.0 still performed superiorly in this domain, receiving 70% 'good' ratings, compared to 40% in ChatGPT-3.5 and 45% in Google Bard (Pearson's chi-squared test, all p ≤ 0.001).

INTERPRETATION

Our findings underscore the potential of LLMs, particularly ChatGPT-4.0, for delivering accurate and comprehensive responses to myopia-related queries. Continuous strategies and evaluations to improve LLMs' accuracy remain crucial.

FUNDING

Dr Yih-Chung Tham was supported by the National Medical Research Council of Singapore (NMRC/MOH/HCSAINV21nov-0001).

Multiple segment spectacle lenses for myopia control. Part 1: Optics

PURPOSE

To understand and compare the optics of two multiple segment (MS) spectacle lenses (Hoya MiyoSmart and Essilor Stellest) designed to inhibit myopia progression in children.

METHODS

The optics of the two designs are presented, together with geometrical optics-based calculations to understand the impact of the lenses on the optics of the eye. Lenses were evaluated with three techniques: surface images, Twyman-Green interferometry and focimetry. The carrier lens powers and the spatial distribution, powers and forms of the lenslets were measured.

RESULTS

MS lenses as manufactured were found to match most of the design specifications provided by their manufacturers, although some apparent small discrepancies were found. The focimeter-measured power of the lenslets was approximately +3.50 D for the MiyoSmart and +4.00 D for the highly aspheric lenslets of the Stellest design. For both lens designs, image contrast would be expected to become modestly reduced in the focal planes of the distance-correcting carrier lenses. Images become much more degraded in the combined carrier-lenslet focal plane, due to the generation of multiple laterally displaced images formed by adjacent lenslets within the effective pupil. The exact effects observed depended on the effective pupil size and its location with respect to the lenslets, as well as the power and arrangement of the lenslets.

CONCLUSION

Wearing either of these lenses will produce broadly similar effects on retinal imagery.

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

PURPOSE

Initial studies have suggested that multiple segment (MS) spectacle lenses can reduce the progression rate of childhood myopia and axial eye growth. This paper aimed to compare the effectiveness of two different available designs of MS lens and to explore the nature of their control effect.

METHOD

Published data from the only two clinical trials in which changes in mean spherical equivalent refraction (SER) and axial length (AL) for matched groups of myopic children wearing either MS or single-vision (SV) spectacle corrections, recorded over a period of at least 2 years, were further analysed and compared. Both trials involved Chinese children of similar ages and visual characteristics, but the trials were located in different cities. The two MS lenses examined were MiyoSmart or DIMS (Hoya) and Stellest (Essilor).

RESULTS

Absolute changes in SER and AL differed over time during the two trials. However, if the results were expressed in terms of efficacy over successive 6-month periods, then the two MS lenses produced broadly similar results (initial efficacy for the control of myopia progression of about 60%-80%, declining over 2 years to about 35%-55%). Control appears to be absolute rather than proportional.

DISCUSSION

Myopia control may be due to either the additional myopic defocus induced by the MS lenses (i.e., asymmetry of the through-focus image changes about the distance focus) or to the general reduction in image contrast that the lenslets create in the peripheral field.

CONCLUSION

Multiple segment spectacle lenses offer a valuable new approach to the control of myopia progression in children. Further work is required to clarify their mechanism of action and to optimise their design parameters.

Myopia Control Efficacy of Spectacle Lenses With Aspherical Lenslets: Results of a 3-Year Follow-Up Study

PURPOSE

To investigate myopia control efficacy in children who continued wearing spectacle lenses with highly aspherical lenslets (HAL) or switched from spectacle lenses with slightly aspherical lenslets (SAL) and single-vision spectacle lenses (SVL) to HAL for 1 year after a 2-year myopia control trial.

DESIGN

This was a 1-year extension of a randomized clinical trial.

METHODS

Of 54 children who had worn HAL for 2 years, 52 continued wearing HAL (HAL1 group), and of the 53 and 51 children who had originally worn SAL or SVL, 51 and 48 switched to wearing HAL (HAL2 and HAL3 groups) in year 3, respectively. A new SVL (nSVL) group of 56 children was recruited, matched for age, sex, cycloplegic spherical equivalent refraction (SER), and axial length (AL) of the HAL3 group at extension baseline, and used for a comparison of third-year changes. SER and AL were measured every 6 months in year 3.

RESULTS

During year 3, the mean (SE) myopia progression in the nSVL group was -0.56 (0.05) diopters (D). Compared with nSVL, the changes in SER were less in HAL1 (-0.38 [0.05] D, P = .02), HAL2 (-0.36 [0.06] D, P = .01), and HAL3 (-0.33 [0.06] D, P = .005). The mean (SE) AL elongation in the nSVL group was 0.28 (0.02) mm. Compared with nSVL, the elongation in AL was less in the HAL1 (0.17 [0.02] mm, P < .001), HAL2 (0.18 [0.02] mm, P < .001), and HAL3 (0.14 [0.02] mm, P < .001) groups. Myopia progression and axial elongation were comparable in all 3 HAL groups (all P > .05) in year 3.

CONCLUSIONS

Myopia control efficacy has remained in children who wore HAL in the previous 2 years. Children who switched from SAL or SVL to HAL in year 3 had slower myopia progression and axial elongation than that in the control group.

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

Purpose

Ocular pathology may be reduced by slowing myopia progression. The purpose of this study was to evaluate the potential of a novel custom-designed rigid gas permeable (RGP) contact lens to control high myopia by comparing the efficacy of multifocal RGP lenses and single-vision spectacles for high myopia control.

Methods

The medical records of children fitted with spectacles or multifocal rigid gas-permeable lenses between January 2018 and May 2020 were retrospectively reviewed. Children (5-17 years) with non-cycloplegic spherical equivalent refraction of ≤ -6.00 D or spherical equivalent refraction > - 6.00 D with baseline axial length ≥ 26.5 mm, and astigmatism of ≥ -2.00 D were included. Axial length and refraction were measured at baseline, before fitting the participants with multifocal rigid gas-permeable lenses or spectacles, and at 1- and 2-year follow-up visits. Changes in axial length were compared between the groups.

Results

Among the 77 children with 1-year follow-up data, the mean axial elongation was 0.20 ± 0.17 mm and 0.21 ± 0.14 mm in the multifocal rigid gas-permeable and control groups, respectively, without significant differences between groups (F = 0.004, p = 0.835). Among the 41 patients who completed 2 years of follow-up, the mean axial elongation values in the multifocal rigid gas-permeable and control groups were 0.21 ± 0.15 mm and 0.24 ± 0.13 mm, respectively, at the 1-year follow-up, and 0.37 ± 0.27 mm and 0.43 ± 0.23 mm, respectively, at the 2-year follow-up, without significant between-group differences at either time point (p = 0.224).

Conclusion

Axial length increased at a similar rate in both the control (spectacles) and multifocal rigid gas-permeable lens groups, suggesting that multifocal rigid gas-permeable lenses have no significant impact on controlling high myopia progression compared with spectacles.

Low-Dose 0.01% Atropine Eye Drops vs Placebo for Myopia Control: A Randomized Clinical Trial

Importance

Controlling myopia progression is of interest worldwide. Low-dose atropine eye drops have slowed progression in children in East Asia.

Objective

To compare atropine, 0.01%, eye drops with placebo for slowing myopia progression in US children.

Design, Setting, and Participants

This was a randomized placebo-controlled, double-masked, clinical trial conducted from June 2018 to September 2022. Children aged 5 to 12 years were recruited from 12 community- and institution-based practices in the US. Participating children had low to moderate bilateral myopia (-1.00 diopters [D] to -6.00 D spherical equivalent refractive error [SER]).

Intervention

Eligible children were randomly assigned 2:1 to 1 eye drop of atropine, 0.01%, nightly or 1 drop of placebo. Treatment was for 24 months followed by 6 months of observation.

Main Outcome and Measures

Automated cycloplegic refraction was performed by masked examiners. The primary outcome was change in SER (mean of both eyes) from baseline to 24 months (receiving treatment); other outcomes included change in SER from baseline to 30 months (not receiving treatment) and change in axial length at both time points. Differences were calculated as atropine minus placebo.

Results

A total of 187 children (mean [SD] age, 10.1 [1.8] years; age range, 5.1-12.9 years; 101 female [54%]; 34 Black [18%], 20 East Asian [11%], 30 Hispanic or Latino [16%], 11 multiracial [6%], 6 West/South Asian [3%], 86 White [46%]) were included in the study. A total of 125 children (67%) received atropine, 0.01%, and 62 children (33%) received placebo. Follow-up was completed at 24 months by 119 of 125 children (95%) in the atropine group and 58 of 62 children (94%) in the placebo group. At 30 months, follow-up was completed by 118 of 125 children (94%) in the atropine group and 57 of 62 children (92%) in the placebo group. At the 24-month primary outcome visit, the adjusted mean (95% CI) change in SER from baseline was -0.82 (-0.96 to -0.68) D and -0.80 (-0.98 to -0.62) D in the atropine and placebo groups, respectively (adjusted difference = -0.02 D; 95% CI, -0.19 to +0.15 D; P = .83). At 30 months (6 months not receiving treatment), the adjusted difference in mean SER change from baseline was -0.04 D (95% CI, -0.25 to +0.17 D). Adjusted mean (95% CI) changes in axial length from baseline to 24 months were 0.44 (0.39-0.50) mm and 0.45 (0.37-0.52) mm in the atropine and placebo groups, respectively (adjusted difference = -0.002 mm; 95% CI, -0.106 to 0.102 mm). Adjusted difference in mean axial elongation from baseline to 30 months was +0.009 mm (95% CI, -0.115 to 0.134 mm).

Conclusions and Relevance

In this randomized clinical trial of school-aged children in the US with low to moderate myopia, atropine, 0.01%, eye drops administered nightly when compared with placebo did not slow myopia progression or axial elongation. These results do not support use of atropine, 0.01%, eye drops to slow myopia progression or axial elongation in US children.

Trial Registration

ClinicalTrials.gov Identifier: NCT03334253.

Comparison of optical myopia control interventions: effect on peripheral image quality and vision

This study compares the effects on peripheral vision and image quality of four myopia control interventions: a) Perifocal spectacles/ArtOptica, b) Stellest spectacles/Essilor), c) MiyoSmart spectacles/Hoya and d) MiSight contact lenses/CooperVision. Five subjects participated with habitual or no correction as reference. Three techniques were used: 1) Hartmann-Shack sensors for wavefront errors, 2) double-pass imaging system for point-spread-functions (PSF), and 3) peripheral acuity evaluation. The results show that multiple evaluation methods are needed to fully quantify the optical effects of these myopia control interventions. Perifocal was found to make the relative peripheral refraction (RPR) more myopic in all subjects and to interact with the natural optical errors of the eye, hence showing larger variations in the effect on peripheral vision. MiSight had a smaller effect on RPR, but large effect on peripheral vision. Stellest and MiyoSmart also showed small effects on RPR but had broader double-pass PSFs for all participants, indicating reduced retinal contrast. Reduction in peripheral retinal contrast might thereby play a role in slowing myopia progression even when the peripheral refraction does not turn more myopic.

Prevention and management of childhood progressive myopia: National consensus guidelines

Myopia is a major public health problem worldwide, including India, with the global prevalence of myopia increasing rapidly over decades. The clinical and socioeconomic impact of myopia is also expected to rise with rising prevalence. Therefore, the focus has now been shifted to prevent the incidence and progression of myopia. However, there is lack of any standardized guidelines for myopia management. This document aims to generate a national-level expert consensus statement on the management of childhood myopia in the Indian scenario. The expert panel of pediatric ophthalmologists consisted of 63 members who met in a hybrid meeting. A list of topics deliberating discussion in the meeting was provided to the experts in advance and they were instructed to provide their opinions on the matter during the meet. The panel of experts then gave their views on each of the items presented, deliberated on different aspects of childhood myopia, and reached a consensus regarding the practice patterns in the Indian scenario. In case of opposing views or lack of a clear consensus, we undertook further discussion and evaluated literature to help arrive at a consensus. A written document is prepared based on recommendations explaining definition of myopia, refraction techniques, components and methods of workup, initiation of anti-myopia treatment, type and timing of interventions, follow-up schedule, and indications for revised or combination treatment. This article formulates evidence-based guidelines for progressing myopes and pre-myopes and also establishes uniformity in the management of childhood myopia in the country.