MGR Doctores, Madrid, Spain.
Eye Contact Lens. 2013 Jul;39(4):269-72. doi: 10.1097/ICL.0b013e318295b4f4.
To compare the number of ordered lenses required to achieve an optimal lens fit between three-point-touch and apical touch fittings in keratoconus subjects with nipple and oval cones using the first definite apical clearance lens (FDACL) as a starting point.
First trial lens was selected following manufacturer's guidelines and the back optic zone radius (BOZR) was flattened or steepened in 0.10 mm steps until a FDACL was found. Subsequently, subjects were randomly allocated to three-point-touch (BOZR 0.10 mm flatter than FDACL) and apical touch fittings (BOZR 0.40 mm flatter than FDACL). Changes were made solely in total lens diameter, edge lift, and/or back vertex power until an optimal lens fit was achieved. Differences between fitting approaches were compared in terms of optimal lens fit rates defined as the percentage of subjects successfully fitted with the first lens ordered from the manufacturer.
Sixty-one subjects (109 eyes) were randomly allocated to three-point-touch and apical touch fitting approaches. An average of 2.3 trial lenses were necessary to achieve the FDACL. An optimal lens fit rate was achieved with the first lens in 84 of 109 eyes (77%). No statistically significant differences in optimal lens fit rates were found between three-point-touch and apical touch fitting approaches (83% and 71%, respectively; P = 0.12) and between nipple and oval cones (81% and 68%, respectively; P = 0.12).
The use of the FDACL provides a systematic, reliable, and repeatable starting point for Rose K2 contact lens fitting in keratoconus. Eye care practitioners should anticipate higher optimal lens fit rates when using three-point-touch (83%) in comparison with apical touch contact lens fittings (71%).
在使用首次确定的顶点间隙镜片（FDACL）作为起始点的情况下，比较圆锥角膜患者中乳头和椭圆形圆锥角膜患者达到最佳镜片拟合所需的三点触摸和顶点触摸拟合的镜片订购数量。
根据制造商的指南选择初始试镜镜片，并以 0.10mm 的步长逐渐平坦或陡峭后光学区半径（BOZR），直到找到 FDACL。随后，将受试者随机分配到三点触摸（BOZR 比 FDACL 平坦 0.10mm）和顶点触摸拟合（BOZR 比 FDACL 平坦 0.40mm）。仅通过改变总镜片直径、边缘提升和/或后顶点功率来实现最佳镜片拟合。比较两种拟合方法之间的差异，最佳镜片拟合率定义为成功按照制造商的订单为第一位患者配到合适镜片的比例。
61 名患者（109 只眼）被随机分配到三点触摸和顶点触摸拟合方法。平均需要 2.3 个试镜镜片才能达到 FDACL。在 109 只眼中，有 84 只（77%）眼可以通过第一副镜片获得最佳镜片拟合。在最佳镜片拟合率方面，三点触摸和顶点触摸拟合方法之间（分别为 83%和 71%，P=0.12）以及乳头和椭圆形圆锥角膜之间（分别为 81%和 68%，P=0.12）均无统计学显著差异。
FDACL 的使用为圆锥角膜的 Rose K2 隐形眼镜拟合提供了一个系统、可靠和可重复的起点。当使用三点触摸（83%）时，眼保健医生应该预期会比顶点触摸隐形眼镜拟合（71%）更高的最佳镜片拟合率。
