Romero-Jiménez Miguel, Santodomingo-Rubido Jacinto, Flores-Rodríguez Patricia, González-Méijome Jose-Manuel
MGR Doctores, Madrid, Spain.
Menicon Co. Ltd., Madrid, Spain.
J Optom. 2015 Jan-Mar;8(1):48-55. doi: 10.1016/j.optom.2014.07.007. Epub 2014 Sep 4.
To evaluate changes in anterior corneal topography and higher-order aberrations (HOA) after 14-days of rigid gas-permeable (RGP) contact lens (CL) wear in keratoconus subjects comparing two different fitting approaches.
Thirty-one keratoconus subjects (50 eyes) without previous history of CL wear were recruited for the study. Subjects were randomly fitted to either an apical-touch or three-point-touch fitting approach. The lens' back optic zone radius (BOZR) was 0.4mm and 0.1mm flatter than the first definite apical clearance lens, respectively. Differences between the baseline and post-CL wear for steepest, flattest and average corneal power (ACP) readings, central corneal astigmatism (CCA), maximum tangential curvature (KTag), anterior corneal surface asphericity, anterior corneal surface HOA and thinnest corneal thickness measured with Pentacam were compared.
A statistically significant flattening was found over time on the flattest and steepest simulated keratometry and ACP in apical-touch group (all p<0.01). A statistically significant reduction in KTag was found in both groups after contact lens wear (all p<0.05). Significant reduction was found over time in CCA (p=0.001) and anterior corneal asphericity in both groups (p<0.001). Thickness at the thinnest corneal point increased significantly after CL wear (p<0.0001). Coma-like and total HOA root mean square (RMS) error were significantly reduced following CL wearing in both fitting approaches (all p<0.05).
Short-term rigid gas-permeable CL wear flattens the anterior cornea, increases the thinnest corneal thickness and reduces anterior surface HOA in keratoconus subjects. Apical-touch was associated with greater corneal flattening in comparison to three-point-touch lens wear.
比较两种不同的验配方法，评估圆锥角膜患者佩戴14天硬性透气性（RGP）隐形眼镜（CL）后角膜前表面地形图和高阶像差（HOA）的变化。
招募31例无CL佩戴史的圆锥角膜患者（50只眼）进行研究。将患者随机分为顶点接触或三点接触验配方法。镜片的后光学区半径（BOZR）分别比首个确定顶点间隙镜片平0.4mm和0.1mm。比较基线时和佩戴CL后用Pentacam测量的最陡、最平及平均角膜曲率（ACP）读数、中央角膜散光（CCA）、最大切向曲率（KTag）、角膜前表面非球面性、角膜前表面HOA以及最薄角膜厚度的差异。
顶点接触组中，随着时间推移，最平及最陡模拟角膜曲率计读数和ACP出现统计学显著变平（所有p<0.01）。佩戴隐形眼镜后，两组的KTag均出现统计学显著降低（所有p<0.05）。随着时间推移，两组的CCA（p=0.001）和角膜前表面非球面性均出现显著降低（p<0.001）。佩戴CL后，角膜最薄点处的厚度显著增加（p<0.0001）。两种验配方法佩戴CL后，彗差样和总HOA均方根（RMS）误差均显著降低（所有p<0.05）。
短期佩戴硬性透气性CL可使圆锥角膜患者的角膜前表面变平，增加最薄角膜厚度并减少角膜前表面HOA。与三点接触镜片佩戴相比，顶点接触导致更大程度的角膜变平。
