Orthokeratology in myopic children

Introduction
Orthokeratology is reversible clinical procedure which can reduce myopia using contact lenses made of high gas permeable material with 4 curves reverse geometry shape. Purpose: The aim of the paper is to evaluate vision acuity and progression of myopia and corneal curvature during use of overnight RGP lenses.

Material and methods
The studies have been performed in 132 patients (264 eyes) in age 5 – 18 years (average 12.5 years) with myopia from -1.50 Dsph to -5.50 Dsph and astigmatism from 0.25 Dsph to 1.25 Dsph. In all patients corneal radius (automatic keratorefractometer) and corneal refractive power (corneal topography) was measured before and after 3 months of wearing during night RGP lenses. Refraction was measured with the use of autokeratorefraktometer after 2 to 6 years of wearing lenses.

Results
In all patients reduction of corneal refractive power (on average 3.05 Dsph) and increase of corneal radiuses (on average 0.4 mm) has been observed. After 2 to 6 years of wearing during night RGP lenses refraction was the same in 48.5% of children, worsened in 31.8% of -0.50 Dsph and progressed of -1.00 Dsph in 19.7% of patients.

Conclusions
Orthokeratology reduces myopia due to temporary changes in corneal curvature.