Personalized Predictive Modeling of Subfoveal Choroidal Thickness Changes for Myopic Adolescents after Overnight Orthokeratology

Changes in Subfoveal Choroidal Thickness after Orthokeratology in Myopic Children: A Systematic Review and Meta-Analysis

AIMS

This study aimed to synthesize the variations in subfoveal choroidal thickness (SFCT) observed at different follow-up intervals in myopic children undergoing orthokeratology treatment.

MATERIALS AND METHODS

Relevant articles were systematically retrieved from databases such as PubMed, EMBASE, Web of Science, and Cochrane Library. The retrieval period extended from the inception of these databases to November 2023. Means and standard deviations (SD) of baseline and post-treatment SFCT were selected as the results for analysis and calculation.

RESULTS

A total of eight articles involving 478 eyes fulfilled the inclusion criteria. At 1 month, 3 months, and 6 months intervals, the SFCT demonstrated significant increases by 16.74 μm (95% CI: 8.66, 24.82; p < 0.0001), 13.41 μm (95% CI: 4.36, 22.45; p = 0.004), and 17.57 μm (95% CI: 8.41, 26.73; p = 0.0002), respectively. Besides, children treated with orthokeratology exhibited a notably thicker change of SFCT in comparison with children with single-vision spectacles (SVL) (WMD = 13.50, 95% CI: 11.69, 15.13; p < 0.0001).

CONCLUSION

Myopic children undergoing orthokeratology treatment experience a discernible increase in SFCT at 1 month, 3 months, and 6 months. Furthermore, compared to children utilizing SVL, those undergoing orthokeratology manifest a more pronounced thickening of SFCT.

Long-term effect of orthokeratology on choroidal thickness and choroidal contour in myopic children

PURPOSE

To investigate the long-term effect of orthokeratology (ortho-k) on the choroidal thickness and choroidal contour in myopic children.

METHODS

Subjects were from a conducted 2-year randomised clinical trial. Children (n=80) aged 8-12 years with spherical equivalent refraction of -1.00 to -6.00D were randomly assigned to the control group (n=40) and ortho-k group (n=40). Optical coherence tomography images were collected at the baseline, 1-month, 6-month, 12-month, 18-month and 24-month visits, then the choroidal thickness and choroid contour were calculated. Axial length (AL) and other ocular biometrics were also measured.

RESULTS

During 2 years, in the control group, the choroidal thickness became thinning and the choroidal contour became prolate with time at all visits (all p<0.001). Ortho-k can improve the choroidal thickness (all p<0.001) and maintain the choroidal contour at all visits (all p<0.05). In the ortho-k group, the choroidal contour was less changed in the temporal than nasal (p=0.008), and the choroidal thickness was more thickening in the temporal 3 mm (p<0.001). Two-year change in choroidal thickness was significantly associated with the 2-year AL change in the control group (r=-0.52, p<0.001), however, this trend was broken by ortho-k (r=-0.05, p=0.342). After being adjusted by other variables in the multivariable regression model, the effect of ortho-k on choroidal thickness was stable.

CONCLUSIONS

In the current 2-year prospective study, ortho-k can improve the choroidal thickness and maintain the choroidal contour, but this effect diminished in a long term. Further study with larger sample size and longer follow-up is warranted to refine this issue.

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.