Bayesian Meta-Analysis of Myopia Control with Multifocal Lenses

Optics of spectacle lenses intended to treat myopia progression

SIGNIFICANCE

This is a review of the optics of various spectacle lenses that have been used in myopia control over the last 60 years, with emphasis on approximately the last 15 years.Myopia has become an increasing health problem worldwide, particularly in some East Asian countries. This has led to many attempts to slow its progression in children and reduce its endpoint value. This review is concerned with the optics of spectacle lenses for use in myopia control, from bifocal lenses to multisegment and diffusion optics lenses. Treatments are based on theories of the onset or progression of myopia. These include the hypotheses that eye growth and myopia in susceptible children may be stimulated by (1) poor accommodation response and the consequent hyperopic defocus with near vision tasks, (2) relative hyperopic peripheral refraction, and (3) high retinal image contrast as occurs in urban environments. Using spectacle lenses to slow myopia progression has a history of about 60 years. The review is laid out in approximately the order in which different types of lenses have been introduced: bifocals, conventional progressive addition lenses, undercorrection with single-vision lenses, specialized progressive addition lenses, defocus-incorporated multiple segments, diffusion optics, and concentric bifocals. In the review, some of the lenses are combined with an eye model to determine refractive errors for peripheral vision for the stationary eye and for foveal vision for the rotating eye. Numbers are provided for the reported success of particular designs in retarding myopia progression, but this is not an epidemiological paper, and there is no critical review of the findings. Some of the recent treatments, such as multiple segments, appear to reduce the eye growth and myopia progression by better than 50% over periods of up to 2 years.

Evaluation of the corneal topography based on deep learning

Purpose

The current study designed a unique type of corneal topography evaluation method based on deep learning and traditional image processing algorithms. The type of corneal topography of patients was evaluated through the segmentation of important medical zones and the calculation of relevant medical indicators of orthokeratology (OK) lenses.

Methods

The clinical data of 1,302 myopic subjects was collected retrospectively. A series of neural network-based U-Net was used to segment the pupil and the treatment zone in the corneal topography, and the decentration, effective defocusing contact range, and other indicators were calculated according to the image processing algorithm. The type of corneal topography was evaluated according to the evaluation criteria given by the optometrist. Finally, the method described in this article was used to evaluate the type of corneal topography and compare it with the type classified by the optometrist.

Results

When the important medical zones in the corneal topography were segmented, the precision and recall of the treatment zone reached 0.9587 and 0.9459, respectively, and the precision and recall of the pupil reached 0.9771 and 0.9712. Finally, the method described in this article was used to evaluate the type of corneal topography. When the reviewed findings based on deep learning and image processing algorithms were compared to the type of corneal topography marked by the professional optometrist, they demonstrated high accuracy with more than 98%.

Conclusion

The current study provided an effective and accurate deep learning algorithm to evaluate the type of corneal topography. The deep learning algorithm played an auxiliary role in the OK lens fitting, which could help optometrists select the parameters of OK lenses effectively.

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.

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.

Effect of multifocal spectacle lenses on accommodative errors over time: Possible implications for myopia control

The study purpose was to improve understanding of how multifocal spectacle lenses affect accommodative errors and whether this changes over time. Fifty-two myopes aged 18 to 27 years were allocated randomly to one of two progressive addition lens (PAL) types with 1.50 D additions and different horizontal power gradients across the near-periphery boundary. Lags of accommodation were determined with a Grand Seiko WAM-5500 autorefractor and a COAS-HD aberrometer for several near distances with the distance correction and the near PAL correction. For the COAS-HD the neural sharpness (NS) metric was used. Measures were repeated at three-month intervals over 12 months. At the final visit, lags to booster addition powers of 0.25, 0.50, and 0.75 D were measured. Except at baseline, both PALs' data were combined for analysis. For the Grand Seiko autorefractor, both PALs reduced accommodative lag at baseline compared with SVLs (p < 0.05 and p < 0.01 at all distances for PAL 1 and PAL 2, respectively). For the COAS-HD, at baseline PAL 1 reduced accommodative lag at all near distances (p < 0.02), but PAL 2 only at 40 cm (p < 0.02). Lags measured with COAS-HD were greater for shorter target distances with PALs. After 12 months' wear, the PALs no longer reduced accommodative lags significantly, except at 40 cm distance, but 0.50 D and 0.75 D booster adds decreased the lags to those measured at baseline or less. In conclusion, for PALs to reduce accommodative lag effectively, addition power should be tailored to typical working distances and after the first year of wear should be boosted by at least 0.50 D to maintain efficacy.

One-year Efficacy of the Defocus Incorporated Multiple Segment Lens in Chinese Myopic Children

SIGNIFICANCE

These data demonstrate that defocus incorporated multiple segment (DIMS) lens reduces myopia progression in children during the first year of use.

PURPOSE

This study aimed to investigate the efficacy of DIMS myopia control spectacle lens in Chinese myopic children aged 6 to 15 years.

METHODS

This is a retrospective study of 1-year longitudinal data. A total of 180 Chinese myopic children were selected from patients at Zhongshan Ophthalmic Center, Sun Yat-sen University, from February 2018 to January 2021. One group consisted of 90 children aged 6 to 15 years, with spherical equivalent refraction -0.50 to -7.75 D (-3.82 ± 1.57 D) and fitted with the DIMS lens. The other group consisted of 90 children fitted with single-vision spectacle lenses and matched with the DIMS group for age, sex, refraction, and progression of myopia in the previous year. One-year myopia progression was measured retrospectively in two groups. Unpaired t test was used to compare the myopia progression between the DIMS group and the control group. Pearson correlation was used to explore the relationship between myopia progression, age, and baseline refraction.

RESULTS

After 1 year of DIMS lens wear, myopia progression was significantly lower in the DIMS group (-0.51 ± 0.50 vs. -0.85 ± 0.51 D, P < .001). Myopia progression was positively correlated with age in both groups. The difference between the DIMS and control groups was more pronounced for children aged 10 to 15 years than for children aged 6 to 9 years.

CONCLUSIONS

This study confirms that the DIMS lens reduces myopia progression during the first year of use. Efficacy seems to increase with age.

Efficacy and Safety of Different Add Power Soft Contact Lenses on Myopia Progression in Children：A systematic review and meta-analysis

BACKGROUND

In children, myopia has become a widespread and serious global public health problem. Soft multifocal contact lenses (SMCLs) have been widely studied to control myopia progression in children. However, their efficacy in myopia control in children and its adverse effects, and which added power SMCLs are more effective and safe remains to be explored.

OBJECTIVES

Evaluate the efficacy and safety of various add power SMCLs to slow myopia progression in children.

METHOD

Eligible randomized controlled trials (RCTs) were retrieved from PubMed, MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases. The present meta-analysis analyzed the mean differences (MD) in myopic progression, axial length, and odds ratios (ORs) for adverse effects and dropout rates between SMCLs with different added powers and control groups. Changes in visual performance were also systematically evaluated.

RESULTS

Seven independent studies involving 805 children were included in the present meta-analysis. At 1-year, the weighted mean difference (WMD) in myopia progression between SMCL and control groups was -0.22 diopters (D) (95% CI, -0.56-0.12 D) for low add power SMCLs, 0.09 D (95% CI, 0-0.19 D) for medium add power, and 0.2 D (95% CI. 0.13, 0.27 D) for high add power. At 2-years, the WMD for medium add power was 0.12 D (95% CI, -0.03-0.27 D), and for high add power was 0.25 D (95% CI, 0.14-0.35 D). No differences were detected for adverse effects (p = 0.2) and acceptability (p = 0.74) between different added powers. Additionally, differences in visual performance changes, produced by different added powers, were not detected.

CONCLUSIONS

The present meta-analysis showed that high add power SMCLs are more effective and stable to control myopia progression. Besides, the adverse effects and acceptability were not related to the added power.

A Clinical Study of the Impact of Soft Contact Lenses on the Progression of Myopia in Young Patients

PURPOSE

To assess the impact of soft contact lenses on the progression of myopia in young patients.

PATIENTS AND METHODS

The observational study included 102 patients divided into 3 groups: MFCL (multifocal contact lenses) group: 15 girls and 9 boys, aged 8-20 (= 14.12 ± 2.863) with soft multifocal contact lenses with myopia: = -3.12 D ± 1.776 D and mean myopia progression -0.23 ± 0.233D after 2 years; SVCL (single vision contact lenses) group: 30 girls and 5 boys, 11-20 years old (=15.5 ± 2.24) with myopia = -2.88 ± 2.122 D at admission and mean myopia progression -0.54 ± 0.464 D after 2 years; the spectacle (single vision glasses) group: 25 girls and 18 boys, aged 8-18 years ( = 13.65 ± 2.448) with single vision glasses with myopia: = -1.74 ± 1.412 D at admission and mean myopia progression -0.86 ± 0.489D after 2 years. Medical history and physical examination were performed every 6, 12, 18 and 24 months. Refractive error was examined using the autorefractometry after cycloplegia.

RESULTS

The analysis of myopia correction after 2 years showed differences between MFCL and spectacle correction. The change in myopia progression after 2 years was statistically significant for MFCL vs SVCL and MFCL vs spectacle correction when the myopia occured before the period of intensive growth. When myopia occurred during the period of intensive growth, difference was noted for MFCL vs spectacle correction and SVCL vs spectacle correction. When myopia occurred after a period of intensive growth, no significant differences between the groups were observed.

CONCLUSION

1) Multifocal contact lenses and some single vision contact lenses (Biofinity) may be useful in the control of myopia in younger patients, slowing the progression of nearsightedness; therefore, they can be a therapeutic option in inhibiting the progression of myopia. 2) The best effects of using multifocal contact lenses occur if myopia is diagnosed before the period of intensive growth.

Myopia Control With Multifocal Lens in School-Aged Children: A Meta-Analysis

BACKGROUND

Myopia is one of the most common eye diseases in school-aged children. Multifocal lens (MFL) is one of the interventions that has being widely applied to control the progress of myopia. However, the treatment effects of MFLs in school-aged children require to be systematically evaluated.

METHODS

A systematic analysis on qualified randomized controlled trials (RCTs) in which MFLs were prescribed as the intervention and single-vision lenses (SVLs) as the control was conducted. The treatment effects referring to the mean differences in spherical equivalent refraction (SER) and axial length (AL) between MFLs and SVLs groups were analyzed.

RESULTS

With annual visit (3-years follow-up), the weighted mean differences (WMDs) in SER between MFLs and SVLs were 0.29 D (95% CI, 0.21 ∼ 0.37, p < 0.00001), 0.46 D (95% CI, 0.32 ∼ 0.60, p < 0.00001), and 0.64 D (95% CI, 0.40 ∼ 0.88, p < 0.00001) at the first, second, and third year; in AL were -0.12 mm (95% CI, -0.14 ∼-0.11, p < 0.00001), -0.19 mm (95% CI, -0.22 ∼-0.16, p < 0.00001), and -0.26 mm (95% CI, -0.31 ∼-0.21, p < 0.00001) at the first, second, and third year. With 6-months interval trials (2-years follow-up), the WMDs in SER from MFLs were 0.14 D (95% CI, 0.08 ∼ 0.20, p < 0.0001), 0.19 D (95% CI, 0.11 ∼ 0.28, p < 0.0001), 0.24 D (95% CI, 0.16 ∼ 0.33, p < 0.0001), 0.31 D (95% CI, 0.18 ∼ 0.44, p < 0.0001) and in AL from MFLs were -0.08 mm (95% CI, -0.09 ∼-0.07, p < 0.00001), -0.10 mm (95% CI, -0.12 ∼-0.09, p < 0.00001), -0.14 mm (95% CI, -0.17 ∼-0.11, p < 0.00001), and -0.18 mm (95% CI, -0.22 ∼-0.14, p < 0.00001) slower comparing with SVLs at follow up of 6, 12, 18, and 24 months, respectively.

CONCLUSION

The treatment effects of MFLs to slow down the myopic progress are positive in both 6-months and annual-visit trials and which could be sustained till 36 months. While a slight weaker treatment effect was observed after the first visit in 6-months visit, a slight rebound was observed at the following visit points. Furthermore, the treatment effects in annual visit are more profound than 6-months visit at almost all stages especially in SER. Our analysis encourages the MFLs users to maintain a long-term treatment with annual visit.