Effect of Three Types of Specially-Designed Myopia Control Spectacle Lenses on Astigmatism: A Two-Year Result

This study sought to determine whether specially-designed myopia control spectacle lenses had any effect on astigmatism in clinical practice.

Medical records of 74 patients (age: 6 to 12 years old) involving the use of MyoVision (n = 23), DIMS (n = 22) and Stellest lenses (n = 29) were collected from the West China Hospital. Data collection included baseline age, sex and spectacle lens prescription at baseline and at the 2-year follow-up. Astigmatism, determined by cycloplegic objective and subjective refraction, was divided into its power vector components, J₀ and J₄₅.

After 2 years of lens wear, for the MyoVision, DIMS and Stellest groups, the total astigmatism increased by -0.41 ± 0.29 D, -0.42 ± 0.34 D and -0.41 ± 0.31 D, respectively (all p < 0.001). The J₀ vector increased by 0.19 ± 0.15 D, 0.19 ± 0.18 D and 0.20 ± 0.16 D, respectively (all p < 0.001). The J₄₅ vector did not change significantly for MyoVision and Stellest (p = 0.12, 0.21), but did decrease significantly with DIMS (p = 0.02) although the magnitude (-0.07 ± 0.14 D) was not clinically significant. The changes in total astigmatism, J₀ and J₄₅ were comparable between the three groups (p = 0.99, 0.97 and 0.32, respectively). Multivariate linear regression analyses showed that the change in astigmatism was correlated only with the change of SER (standard β = 0.31, p = 0.006).

The use of specially-designed myopia control spectacle lenses over 2 years resulted in a slight, but clinically insignificant (<0.50 D) increase in refractive astigmatism. The increase was not associated with lens type, but rather with the increase in myopia.