Long-term observation of corneal complications and effectiveness by orthokeratology for myopia

AIM:To observe the long-term effectiveness and corneal complications by orthokeratology in myopia patients. METHODS:A retrospective analysis was conducted for 324 patients(620 eyes)with myopia who weared orthokeratology lens with standardized examination and strict recheck. The change of uncorrected visual acuity, myopic diopter, corneal curvature, visual quality and the complications after continuous wearing orthokeratology for 6mo, 1 and 2a were observed. RESULTS:The uncorrected visual acuity was 0.15±0.14 before orthokeratology, 0.95±0.07 at 6mo after wearing, 0.93±0.10 after 1a, 0.90±0.10 after 2a, which was increased significantly in every group compared with that before wearing(P<0.01). The myopic diopter was -3.34±1.43D before wearing orthokeratology, -0.73±0.67D at 6mo after wearing, -0.93±0.57D after 1a, -0.97±0.66D after 2a, which was decreased apparently in every group compared with that before wearing(P<0.01). The corneal curvature was 43.27±1.23D before wearing orthokeratology, 40.69±1.22D at 6mo after wearing, 40.64±1.21D after 1a, 40.36±1.16D after 2a, which was decreased significantly in every group compared with that before wearing(P<0.01). During the period of orthokeratology wearing, 397 eyes had mild corneal epithelial injury(0～Ⅱ), the incidence rate was 64.0%, which was relieved after promoting restoration drugs for corneal epithelium. The corneal epithelial injury at Ⅲ degree occurred in only 5 eyes, and the incidence rate was 0.8%. Only 1 patient had to stopped wearing orthoeratology for filamentary keratitis and cured with drugs. The pressure mark occurred in 106 eyes, and the incidence rate was 17.1%. Diplopia or double image happened in 144 eyes, and the incidence rate was 23.2%. Dazzle occurred in 161 eyes, and the incidence rate was 26.0%. These problems could disappeared with time or after adjusting lenses. CONCLUSION:Long-term orthokeratology wearing can efficiently improve the uncorrected visual acuity, decrease the myopic diopter and corneal curvature. The standardized examination and strict recheck can ensure the safety of orthokeratology.