Design-Dependent Myopia Control in Orthokeratology: Spherical Versus Aspherical Back Optic Zone Profiles.

Area of Science:

• Ophthalmology
• Optometry
• Biomedical Engineering

Background:

• Orthokeratology (Ortho-K) lenses are used for myopia control.
• Spherical and aspherical lens designs exist for Ortho-K.
• Evaluating their efficacy in myopia control and corneal stability is crucial.

Purpose of the Study:

• To compare the effectiveness of spherical versus aspherical Ortho-K lenses.
• To assess myopia control and corneal optical stability over one year.
• To analyze differences in axial length, visual acuity, and aberrations.

Main Methods:

• Retrospective analysis of a 12-month, two-center, randomized clinical trial.
• 48 children (8-15 years) wore both spherical and aspherical Ortho-K lenses.
• Measurements included axial length, visual acuity, lens decentration, corneal power, and aberrations.

Main Results:

• Both lens designs induced typical Ortho-K corneal reshaping.
• Aspherical lenses showed significantly slower axial length elongation (p < 0.01).
• Aspherical lenses resulted in more stable treatment zones and fewer higher-order aberrations.

Conclusions:

• Aspherical Ortho-K lenses provide superior myopia control compared to spherical designs.
• Aspherical lenses promote greater corneal optical stability over 12 months.
• The findings support the use of aspherical Ortho-K for enhanced myopia management.