School of Optometry and Vision Science, University of New South Wales, Kensington, Australia.
Cornea. 2010 Nov;29(11):1223-31. doi: 10.1097/ICO.0b013e3181d3d660.
To examine for epithelial thickness changes in response to compressive and shear forces associated with eye rubbing.
The Holden-Payor optical pachometer was used to measure total and stromal-endothelial thickness, at central (right eye) and midperipheral (left eye) locations, for 12 subjects with normal corneas. Epithelial thickness was determined by subtraction. Baseline measurements were compared with measurements recorded immediately after 15 seconds of circular pattern rubbing over the cornea, using an index finger pad, and light to moderate force. Four subjects in each of 3 groups with mean ages of 19.5, 45.3, and 70.2 years were assessed. Measurement continued at 15-minute intervals until baseline thickness was restored.
An 18.4% reduction in epithelial thickness was recorded immediately after rubbing for central right eye and midperipheral left eye assessments. Both findings were statistically significant (P < 0.05). Recovery to baseline thickness occurred between 15 and 30 minutes centrally and between 30 and 45 minutes midperipherally.
These results indicate a statistically significant mechanical trauma to the epithelium after 15 seconds of light to moderate rubbing. With reference to the rheological properties of the cytoskeleton, an attempt to explain how the epithelium could lose and recover thickness has been made. Apart from cell flattening, displacement from the rubbed area of intercellular water, cytoplasm from ruptured cells, chains of wing cells, and mucin are suggested as possible thinning mechanisms. Extraneous eye rubbing may adversely alter the results obtained with pachymetry, videokeratography, wavefront aberrometry, refraction, and results obtained with orthokeratology contact lenses.
观察与眼揉相关的压缩力和剪切力对上皮厚度变化的影响。
使用 Holden-Payor 光学角膜测厚仪测量 12 名正常角膜受试者的中央（右眼）和中周边（左眼）部位的总厚度和基质内皮厚度。通过减法确定上皮厚度。将基线测量值与用食指垫在角膜上进行 15 秒的圆形图案摩擦后立即记录的测量值进行比较，施加轻到中度的力。在每组中评估 4 名年龄分别为 19.5、45.3 和 70.2 岁的受试者。每隔 15 分钟进行测量，直到恢复基线厚度。
中央右眼和中周边左眼评估后，上皮厚度立即减少了 18.4%。这两种发现均具有统计学意义（P<0.05）。中央部位在 15 至 30 分钟之间，中周边部位在 30 至 45 分钟之间恢复到基线厚度。
这些结果表明，在轻到中度摩擦 15 秒后，上皮会受到统计学上显著的机械创伤。根据细胞骨架的流变学特性，尝试解释上皮如何失去和恢复厚度。除了细胞变平外，还提出了细胞间水、来自破裂细胞的细胞质、翼细胞链和粘蛋白从摩擦区域位移等可能的变薄机制。额外的眼部摩擦可能会对角膜测厚术、角膜地形图术、波前像差术、折射术和角膜塑形术接触镜获得的结果产生不利影响。
