Wang Jianhua, Fonn Desmond, Simpson Trefford L
Centre for Contact Lens Research, School of Optometry, University of Waterloo, Waterloo, Ontario, Canada.
Invest Ophthalmol Vis Sci. 2003 Mar;44(3):1070-4. doi: 10.1167/iovs.02-0343.
To determine changes in topographical thickness of the epithelium and total cornea after hydrogel (2-hydroxyethyl methacrylate; HEMA or soft lens) and PMMA rigid contact lens wear with eyes closed, as measured by optical coherence tomography (OCT).
Epithelial and total corneal thickness in 18 neophyte eyes was measured with OCT at intervals of 10 degrees across a 10-mm zone of the horizontal meridian of the cornea, before and after 3 hours of soft and rigid contact lens wear with the eye closed. These measurements were repeated 20 minutes after removal of the lenses.
Lens type, time, and location were found to be significant main influences (P < 0.0001) on corneal swelling in patched eyes, by three-way ANOVA, and there was a significant three-way interaction among lens type, time, and location (F((16,272)) = 1.78, P = 0.033). However, there was no significant main effect and interaction of epithelial thickness (F((16, 272)) = 0.33, P = 0.99). Immediately after removal of the lenses, total corneal thickness in the horizontal meridian was significantly greater with both soft and PMMA lenses (P < 0.001) at each location with each lens, compared with the baseline measurements. With both lenses, the increase in actual thickness and percentage of corneal swelling at the center was greater than at each peripheral point (excluding the first 10 degrees points; P < 0.005). HEMA lenses caused greater corneal swelling than the PMMA lenses at each location immediately after removal of the lenses (P < 0.005).
This study shows that corneal swelling is dependent on lens type and corneal location when eyes are closed, but epithelial thickness across the horizontal corneal meridian does not change during lens wear with eyes closed. OCT is an efficient method of measuring topographical corneal and epithelial thickness in response to contact lens wear.
通过光学相干断层扫描（OCT）测定闭眼佩戴水凝胶（甲基丙烯酸2-羟乙酯；HEMA或软性接触镜）和PMMA硬性接触镜后上皮和全角膜的地形图厚度变化。
对18只初戴者眼睛在闭眼佩戴软性和硬性接触镜3小时前后，使用OCT在角膜水平子午线10毫米区域内每隔10度测量上皮和全角膜厚度。镜片摘除后20分钟重复这些测量。
通过三因素方差分析发现，镜片类型、时间和位置对闭眼时角膜肿胀有显著的主要影响（P<0.0001），并且镜片类型、时间和位置之间存在显著的三因素交互作用（F((16,272)) = 1.78，P = 0.033）。然而，上皮厚度没有显著的主要效应和交互作用（F((16, 272)) = 0.33，P = 0.99）。与基线测量相比，在摘除镜片后立即，软性和PMMA镜片在每个位置的水平子午线全角膜厚度均显著增加（P<0.001）。两种镜片在中心的实际厚度增加和角膜肿胀百分比均大于每个周边点（不包括最初的10度点；P<0.005）。摘除镜片后立即，在每个位置HEMA镜片比PMMA镜片引起的角膜肿胀更大（P<0.005）。
本研究表明，闭眼时角膜肿胀取决于镜片类型和角膜位置，但在闭眼佩戴镜片期间，水平角膜子午线上的上皮厚度没有变化。OCT是一种测量接触镜佩戴后角膜和上皮地形图厚度的有效方法。
