Centre Marsden de Terapia Visual, Consulta 156, Centro Medico Teknon, Barcelona, Spain.
Optom Vis Sci. 2022 Apr 1;99(4):363-371. doi: 10.1097/OPX.0000000000001888.
This study will enhance our understanding of the effects of orthokeratology lens design on corneal profile, the results of which may be useful in developing future orthokeratology lens designs.
This study aimed to evaluate the effect of lens design on corneal power distribution after orthokeratology using mathematical methods.
Sixty-five subjects were enrolled in this prospective study and assigned to four groups: Euclid with 6.2-mm back optic zone diameter (aged <14 years), Euclid with 6.2-mm back optic zone diameter (aged ≥14 years), double tear reservoir lens with 5.0-mm back optic zone diameter, and double tear reservoir lens with 6.0-mm back optic zone diameter. Manifest refraction and corneal topography were checked at baseline and 1 day, 1 week, 2 weeks, and 1 month after lens wear. Relative corneal refractive power change was calculated by a polynomial function and a monomial function. The maximum relative corneal refractive power change (Ymax) and the corresponding distance from the corneal center (Xmax) were analyzed. Relative corneal refractive power change over time and between groups was compared using repeated-measures analysis of variance.
Refractive reduction and central corneal flattening were seen at all follow-up visits after orthokeratology lens wear, being fastest in the 5.0-mm back optic zone diameter group (P < .001). The cornea steepened in an aspheric way toward the midperiphery and peaked at approximately 2 to 3 mm off the apex. Overall, Ymax was not different among the four groups, but Xmax was smallest in the 5.0-mm back optic zone diameter group (P < .001). At 1/2 Xmax, relative corneal refractive power change of the 5.0-mm back optic zone diameter design was significantly higher than that of the other three groups (P < .001). The power exponent of the monomial of the 5.0-mm back optic zone diameter design was greater than that of the other three groups (P < .001).
An orthokeratology lens design with smaller back optic zone diameter might yield a faster myopic reduction and a smaller aspheric treatment zone.
本研究将增进我们对角膜形态学的认识，了解角膜塑形镜设计对角膜形态的影响，这可能有助于开发未来的角膜塑形镜设计。
本研究旨在通过数学方法评估镜片设计对角膜塑形术后角膜屈光力分布的影响。
本前瞻性研究纳入 65 名受试者，分为 4 组：6.2mm 后光学区直径的欧几里得镜（年龄<14 岁）、6.2mm 后光学区直径的欧几里得镜（年龄≥14 岁）、5.0mm 后光学区直径的双泪液储存镜和 6.0mm 后光学区直径的双泪液储存镜。在佩戴镜片前、佩戴后 1 天、1 周、2 周和 1 个月，检查主观验光和角膜地形图。通过多项式函数和单项式函数计算相对角膜屈光力的变化。分析最大相对角膜屈光力变化（Ymax）和角膜中心对应的距离（Xmax）。采用重复测量方差分析比较随时间的相对角膜屈光力变化和组间差异。
佩戴角膜塑形镜后，所有随访时间点均观察到近视屈光度降低和中央角膜变平，在 5.0mm 后光学区直径组最快（P<0.001）。角膜呈非球面方式向中周边变陡，在距顶点约 2 至 3mm 处达到峰值。总的来说，四组之间 Ymax 无差异，但 5.0mm 后光学区直径组的 Xmax 最小（P<0.001）。在 1/2 Xmax 处，5.0mm 后光学区直径设计的相对角膜屈光力变化显著高于其他三组（P<0.001）。5.0mm 后光学区直径设计的单项式幂大于其他三组（P<0.001）。
较小后光学区直径的角膜塑形镜设计可能会更快地降低近视屈光度，并产生更小的非球面治疗区。
Zotero 插件