Optics Department, University of Valencia, Carrer del Dr. Moliner, 50, 46100 Burjassot, Valencia, Spain; Ophthalmic Research Group, School of Life and Health Sciences, Aston University, Birmingham B4 7ET, UK.
Optics Department, University of Valencia, Carrer del Dr. Moliner, 50, 46100 Burjassot, Valencia, Spain.
Cont Lens Anterior Eye. 2018 Feb;41(1):122-127. doi: 10.1016/j.clae.2017.09.014. Epub 2017 Sep 28.
To assess and compare the effect of the corneo-scleral lenses (C-ScL) and scleral lenses (ScL) on tear film parameters and central corneal thickness (CCT) in healthy presbyopic subjects.
Thirty subjects wore two contact lenses (CLs), randomly assigned, of neutral power, but of different diameters, 12.7mm (C-ScL) and 18mm (ScL) and being equal in the others parameters: material (HS100) and centre thickness (0.29mm). At baseline, 20min after insertion and at 8h, the tear meniscus area (TMA) and CCT was measured (with optical coherence tomography) as well as tear osmolarity.
TMA revealed statistical differences for both lenses at 20min (p<0.001), and also at 8h (p=0.003), being greater for the C-ScL. CCT showed statistical differences for both lenses at 20min (p=0.002), and also at 8h (p=0.001), being lower for the C-ScL. Osmolarity did not reveal statistical differences at 20min (p=0.29), while it was statistically different at 8h (p=0.03), being lower for the C-ScL.
C-ScL lead to a lesser reduction in the TMA and a lower induced hypoxic stress than the ScL. Osmolarity levels remained within normal values across the day with no clinical difference between lenses. Both designs can represent a good optical platform for correcting presbyopia as well as protecting the ocular surface by vaulting the cornea.
评估和比较角膜 - 巩膜镜片（C-ScL）和巩膜镜片（ScL）对健康远视受试者泪膜参数和中央角膜厚度（CCT）的影响。
30 名受试者随机佩戴两种具有不同直径的中性力隐形眼镜（CL），直径分别为 12.7mm（C-ScL）和 18mm（ScL），其他参数相同：材料（HS100）和中心厚度（0.29mm）。在基线时、插入后 20 分钟和 8 小时测量泪膜新月形面积（TMA）和 CCT（使用光学相干断层扫描）以及泪液渗透压。
TMA 显示两种镜片在 20 分钟时均有统计学差异（p<0.001），在 8 小时时也有统计学差异（p=0.003），C-ScL 的 TMA 更大。CCT 显示两种镜片在 20 分钟时均有统计学差异（p=0.002），在 8 小时时也有统计学差异（p=0.001），C-ScL 的 CCT 更低。渗透压在 20 分钟时无统计学差异（p=0.29），而在 8 小时时有统计学差异（p=0.03），C-ScL 的渗透压更低。
C-ScL 导致的 TMA 减少和诱导缺氧应激低于 ScL。渗透压水平全天保持在正常范围内，两种镜片之间没有临床差异。这两种设计都可以作为矫正远视以及通过拱起角膜来保护眼表面的良好光学平台。
