J Korean Ophthalmol Soc.  2019 Jul;60(7):620-626. 10.3341/jkos.2019.60.7.620.

Comparison of Myopic Progression before and after Orthokeratology Lens Treatment

• Jung HG
• Lee KY
• Bae GH

• KMID: 2453012
• DOI: http://doi.org/10.3341/jkos.2019.60.7.620

Abstract

PURPOSE
To compare the myopic progression before and after wearing an orthokeratology lens (OK).
METHODS
Twenty-six patients (49 eyes) with at least 6 months of myopia prior to OK treatment were evaluated. Changes in the spherical equivalent (SE) refractive error and axial length were compared before and after OK use. Changes in the SE and axial length were also compared between two groups according to the myopic progression before baseline: Group 1 with myopic progression < 1 D/year and Group 2 with myopic progression > 1 D/year.
RESULTS
The myopic progression rate decreased from −1.1 to −0.3 D/year after OK treatment (p < 0.001). Greater increases in axial length were observed in patients who were younger and had less myopia at baseline, a higher rate of myopia progression before baseline, and a shorter axial length at baseline (p < 0.001, p < 0.004, p < 0.007, and p < 0.001, respectively). The increase in axial length was significantly greater in the group with greater myopic progression before baseline (0.2 mm/year) than in the group with less myopic progression (0.1 mm/year) (p = 0.001).
CONCLUSIONS
Myopic progression was reduced significantly after OK treatment.

Keyword

Myopia; Orthokeratology; Progression

MeSH Terms

Humans
Myopia
Refractive Errors

Figure

• 

  Figure 1 Myopic progression rates of before and after orthokeratology lens (OK) treatment. The mean myopic progression rate from diagnosis to OK (before OK) is −1.1 D/year, which is significantly higher than −0.3 D/year from OK to last follow up (after OK) (*p < 0.001, Wilcoxon Signed-Rank test). The mean myopic progression of 1 year before OK is −1.1 D, which is significantly higher than −0.2 D in 1 year after OK (*p < 0.001, Wilcoxon Signed-Rank test).

• 

  Figure 2 Increase in axial length and age at orthokeratology lens (OK), spherical equivalent refractive error (SE) at OK, SE change (diopter, D)/year and axial length at OK. Significant correlations were found between increase in axial length and age at OK, SE at OK, SE change (D)/year and axial length at OK (Pearson's correlation coefficient, r = −0.482; p < 0.001, r = 0.409; p = 0.004, r = −0.380; p = 0.007, r = −0.554; p < 0.001).

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