Changes in near vision and stereopsis after orthokeratology

AIM:To provide a proper assessment of the clinical use of orthokeratology by observing and analyzing the ocular biometric changes of the eyes and the stereopsis of the myopia.<p>METHODS:Sixty eyes from 30 myopia(from 8 to 17 years old)were fitted with orthokeratology. Stereopsis, visual acuity, near visual acuity, central corneal thickness, anterior chamber depth, average anterior corneal refractive power(<i>K</i> value), and intraocular pressure were measured before the orthokeratology treatment and 3mo after it. Refraction was expressed as spherical equivalent(SE), and the subjects were divided into 3 groups according to refraction: low myopia group(SE<-3.00D), moderate myopia group(-3.00D≤SE<<p>-6.00D), and high myopia group(SE≥-6.00D).<p>RESULTS: All subjects had significant improvements in visual acuity and near visual acuity 3mo after the orthokeratology treatment(<i>P</i><0.01). In the comparisons of any pair of the groups, there was no significant difference in the near visual acuity(<i>P</i>>0.05). Three months after the orthokeratology treatment, Naked eye near stereoacuity values of all subjects were decreased(<i>P</i><0.01). There was no significant difference in the comparisons of the differences of stereopsis between any pair of the groups(<i>P</i>>0.05). There was significant correlation in stereopsis and anisometropia(Pearson coefficient <i>r</i>=0.778, <i>P</i><0.01). And with greater anisometropia, the stereopsis was higher. All subjects had significantly lower <i>K </i>values than before 3mo after the orthokeratology treatment(<i>P</i><0.01). There was no significant difference in central corneal thickness, anterior chamber depth, and intraocular pressure(<i>P</i>>0.05).<p>CONCLUSION: Orthokeratology could lower <i>K</i> value in a short time and change the corneal curvature to correct myopia, to improve visual acuity and near visual acuity. It also has an influence on improving stereopsis. There are no obviously changes in patients' central corneal thickness, anterior chamber depth or intraocular pressure after the orthokeratology treatment, making it a safe and effective treatment for adolescent