Myopia control with orthokeratology contact lenses in Spain: refractive and biometric changes.
OBJECTIVE
To compare axial length growth between white children with myopia wearing orthokeratology contact lenses (OK) and distance single-vision spectacles (SV) over a 2-year period.


METHODS
Subjects 6 to 12 years of age with myopia -0.75 to -4.00 diopters of sphere (DS) and astigmatism ≤1.00 diopters of cylinder (DC) were prospectively allocated OK or SV correction. Measurements of axial length (Zeiss IOLMaster), corneal topography, and cycloplegic refraction were taken at 6-month intervals.


RESULTS
Thirty-one children were fitted with OK and 30 with SV. Following 24 months, axial length increased significantly over time for both the OK group (0.47 mm) and SV group (0.69 mm; P < 0.001), with a significant interaction between time and group (P = 0.05) reflecting a greater increase in the SV group. Significant differences in refraction were found over time, between groups and for the interaction between time and group for spherical (all P < 0.001) but not cylindrical components of refraction (all P > 0.05). Significantly greater corneal flattening was evident in the OK group for the flatter and steeper corneal powers and for corneal shape factor (all P ≤ 0.05).


CONCLUSIONS
Orthokeratology contact lens wear reduces axial elongation in comparison to distance single-vision spectacles in children.
Menicon Co.Ltd. (Madrid Office), Majadahonda, Madrid, Spain. j.santodomingo@menicon.com
Jacinto
J
Santodomingo-Rubido
César
C
Villa-Collar
Bernard
B
Gilmartin
Ramón
R
Gutiérrez-Ortega
D058452:Axial Length, Eye / Q000473:pathology; D001699:Biometry; D002648:Child; D003262:Contact Lenses, Extended-Wear; D019781:Corneal Topography; D005260:Female; D006801:Humans; D008297:Male; D009216:Myopia / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D054158:Orthokeratologic Procedures / Q000379:methods*; D011446:Prospective Studies; D012029:Refraction, Ocular / Q000502:physiology; D013030:Spain