Orthokeratology lenses and myopia control

Purpose: To estimate the stabilizing effect of orthokeratology lenses (ortho-K, OK-lenses) on myopia progression by evaluating axial eye growth dynamics and clinical refraction.

Material and methods. Ortho-K group consisted of 68 children (135 eyes) aged 7–17 years (average age 12.2) with progressive myopia (initially -0.75–6.75 D). Observation period varied from 7 to 30 months (on average 11.68±4.39). All patients used OK-lenses for overnight wear. The control group consisted of 90 patients (180 eyes) with myopia who were prescribed single vision spectacles for vision correction. Comparative analysis was performed for clinical refraction parameters as well as for axial length (AL). The data was obtained with the use of IOL-Master optical biometer (“Carl Zeiss”).

Results. The parameters were stable in patients of ortho-K group: axial length, subjective and objective clinical refraction, the required power of corrective len-ses. However, the parameters changed significantly in the control group during the observation period: uncorrected visual acuity (UCVA) decreased, the required power of corrective lenses increased, the indices of objective clinical refraction strengthened, annual gradient of progression (AGP) amounted to 0.26±0.19 and 0.16±0,39 mm in patients with low and moderate myopia, respectively.

Conclusion. The use of OK-lenses ensures a significant deceleration of myopia progression in children. The results obtained suggest a wider use of ortho-K among pediatric ophthalmologists in their clinical practice as it is an effective preventive and therapeutic method for patients with progressive myopia.

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