Ehrlich D L, Braddick O J, Atkinson J, Anker S, Weeks F, Hartley T, Wade J, Rudenski A
Visual Development Unit, University College London, United Kingdom.
Optom Vis Sci. 1997 Oct;74(10):822-43. doi: 10.1097/00006324-199710000-00022.
Rapid emmetropization is described in pediatrically normal infants from 9 months of age during the following year. The infants, obtained from various categories of the Cambridge population screening program, provided a broad range of refractive errors. The large group of 254 nonanisometropic infants studied allowed the mean rate of change and dependence on the initial refraction value to be determined. Refraction was measured by cycloplegic retinoscopy. Rapid emmetropization changes occurred in the following refractive components: mean spherical equivalent (MSE), astigmatism magnitude, the horizontal astigmatism component, the infant's most positive meridian, and the infant's most negative meridian. The MSE and astigmatism rates of change (diopters/year), were highly dependent on their respective initial powers (r = -0.61 and r = -0.76). The percentage weighted mean proportional rate of change for MSE was -30% (SE 4%) and for astigmatism magnitude it was -59% (SE 14%). There was much individual variation, with some exhibiting fast emmetropization and others not. The MSE and astigmatism changes, however, were almost independent of each other. The refractive errors of the most positive and most negative meridians emmetropize because they are both derived from the MSE and half the astigmatism. With-the-rule astigmatism was more prevalent than against-the-rule astigmatism at 9 months of age, and with-the-rule astigmatism exhibited a significantly greater proportional rate of change. The relationship of emmetropization and refractive screening is considered. A new component "MOMS" is introduced, the maximum ocular meridional separation, when both eyes are considered. Thus incorporating astigmatism and anisometropia may be a good single indicator of conditions associated with later amblyopia. The almost independent emmetropization of the MSE and astigmatism components is an important result to consider in theories of emmetropization, refractive screening, clinical prescribing, and the evaluation of infants in treatment trials.
在接下来的一年中，9个月大的儿科正常婴儿出现了快速正视化现象。这些婴儿来自剑桥人群筛查项目的不同类别，屈光不正范围广泛。对254名非屈光参差性婴儿的大样本研究使得能够确定平均变化率以及对初始屈光值的依赖性。屈光检查采用睫状肌麻痹视网膜检影法。快速正视化变化发生在以下屈光成分中：平均球镜当量（MSE）、散光度数、水平散光成分、婴儿最正的子午线以及婴儿最负的子午线。MSE和散光变化率（屈光度/年）高度依赖于它们各自的初始度数（r = -0.61和r = -0.76）。MSE的加权平均比例变化率为-30%（标准误4%），散光度数的加权平均比例变化率为-59%（标准误14%）。个体差异很大，一些婴儿表现出快速正视化，而另一些则没有。然而，MSE和散光变化几乎相互独立。最正和最负子午线的屈光不正发生正视化，因为它们都源自MSE和一半的散光。在9个月大时，顺规散光比逆规散光更普遍，并且顺规散光的比例变化率显著更大。探讨了正视化与屈光筛查的关系。引入了一个新成分“MOMS”，即考虑双眼时的最大眼子午线间距。因此，纳入散光和屈光参差可能是与后期弱视相关状况的一个良好单一指标。MSE和散光成分几乎独立的正视化是在正视化理论、屈光筛查、临床处方以及治疗试验中婴儿评估时需要考虑的一个重要结果。
