Myopia is now recognized as a common condition with prevalence levels in young adolescents.
Recent studies have reported orthokeratology contact lens wear to significantly reduce axial length growth by 30% to 50% in comparison to spectacle and soft contact lens wear.
To examine which baseline measurements constitute predictive factors for axial length growth over 2 years in children wearing orthokeratology contact lenses (OK) and single-vision spectacles (SV).
This study was part of the MCOS study designed to assess the safety, efficacy and subjective acceptance of OK versus SV in White European children with myopia over a 2-year period.
In brief, normal, healthy white European subjects 6 to 12 years of age with moderate levels of myopia (-0.75 to -4.00D) and astigmatism (≦1.00D) and free of systemic or ocular disease were recruited for the study and prospectively assigned to wear OK or SV.
SV group: Subjects were prescribed for constant wear distance single-vision spectacles having the highest positive/least negative power consistent with optimum visual acuity.
OK group:Subjects were fitted with Menicon Z Night contact lenses using Easy Fit Software.
OK配戴隱形眼鏡都是用Easy fit 軟體驗配Menicon Z的夜戴型鏡片
After initial enrolment, subjects were followed at 1, 6, 12, 18, and 24month intervals. Follow-up visits were scheduled to fall within 2 hours of awakening.
A decrease in one line of visual acuity accompanied by a change in subjective refraction at any of the follow-up visits was considered clinically significant and was remedied by supplying contact lenses or spectacles made to the new prescription.
1. 年紀較大的兒童(Figure.1 十歲以上的兒童)
Orthokeratology is a successful treatment option in controlling axial elongation compared to SV in children of older age, had earlier onset of myopia, were female, had lower rate of myopia progression before baseline, had lower myopia at baseline, had longer anterior chamber depth, had greater corneal power, had more prolate corneal shape, had larger iris and pupil diameters, and had lower levels of parental myopia.
這篇研究讓我知道原來眼軸長的變化與那麼多影響因子有關，也讓我知道尤其是在年紀較大的兒童(Figure.1 十歲以上的兒童) 、女生、較早被診斷有近視的兒童、近視度數較淺、前房較深、角膜屈光度較大且角膜形狀較橢圓、虹膜與瞳孔大小較大、父母近視度數少的群組中利用角膜塑型片來控制眼軸變長在這些次變量中相較於配戴眼鏡的比較成功的。