Effects on Ocular Parameters of Myopic Eyes After Orthokeratology in Myopic Children

1.The primary objective of the current study is to investigate changes in uncorrected visual acuity, diopter, accommodation, peripheral refraction, IOP, tear film quality, corneal thickness, corneal topography, corneal biomechanical parameters, objective optical quality, corneal and conjunctiva sensitivity and choroidal thickness for children with different diopters after wearing orthokeratology lenses; 2. Through measure long-term changes of these parameters, including corneal topography, axial length, peripheral refraction, objective optical quality and choroidal thickness, to explore occurrence and development regularity of myopia.

Inclusion Criteria:

• 1. subjects were 6-16 years of age; 2.had no other ocular diseases aside from refractive error and no keratoconus (confirmed by pre-treatment corneal topography); 3. had an intraocular pressure (IOP) of <21 mmHg; 4. had an with-the- rule astigmatism (axes 180 ± 30) ≤ 1.50 D; 5.had a best corrected visual acuity（BCVA） ≤0.00 log MAR units in both eyes (Snellen equivalent to 20/20);

Exclusion Criteria:

• 1. had binocular vision problems; 2.use medications that might affect refractive development; 3.had history of ortho-k or contact lens wear; 4. Ocular surface diseases and other eye diseases which can cause abnormalities of ocular surface; 5. Patients with histories of ocular injury or surgery; 6. Corneal staining and decentration of lens after wearing Ortho-k.

myopia