Alabi Emmanuel, Hutchings Natalie, Bizheva Kostadinka, Simpson Trefford
University of Waterloo, School of Optometry and Vision Science, Waterloo, ON, Canada.
University of Waterloo, School of Optometry and Vision Science, Waterloo, ON, Canada; University of Waterloo, Department of Physics and Astronomy, Waterloo, ON, Canada; University of Waterloo, Systems Design Engineering Department, Waterloo, ON, Canada.
J Optom. 2018 Jan-Mar;11(1):57-65. doi: 10.1016/j.optom.2017.02.003. Epub 2017 Jun 17.
To establish a relationship between the diameter and depth position of vessels in the superior and inferior corneo-scleral limbus using ultra-high resolution optical coherence tomography (UHR-OCT).
Volumetric OCT images of the superior and inferior limbus were acquired from 14 healthy subjects with a research-grade UHR-OCT system. Differences in vessel diameter and depth between superior and inferior limbus were analyzed using repeated measured ANOVA in SPSS and R.
The mean (± SD) superior and inferior diameters were 29±18μm and 24±18μm respectively, and the mean (± SD) superior and inferior depths were 177±109μm and 207±132μm respectively. The superior limbal vessels were larger than the inferior ones (RM-ANOVA, p=0.004), and the inferior limbal vessels were deeper than the superior vessels (RM-ANOVA, p=0.041). There was a positive linear association between limbal vessel depth and size within the superior and inferior limbus with Pearson correlation coefficients of 0.803 and 0.754, respectively.
This study demonstrated that the UHR-OCT was capable of imaging morphometric characteristics such as the size and depth of vessels in the limbus. The results of this study suggest a difference in the size and depth of vessels across different positions of the limbus, which may be indicative of adaptations to chronic hypoxia caused by the covering of the superior limbus by the upper eyelid. UHR-OCT may be a useful tool to evaluate the effect of contact lenses on the microvascular properties within the limbus.
使用超高分辨率光学相干断层扫描（UHR-OCT）建立上下角膜缘血管直径与深度位置之间的关系。
使用研究级UHR-OCT系统从14名健康受试者获取上下角膜缘的容积OCT图像。在SPSS和R中使用重复测量方差分析来分析上下角膜缘血管直径和深度的差异。
上、下直径的平均值（±标准差）分别为29±18μm和24±18μm，上、下深度的平均值（±标准差）分别为177±109μm和207±132μm。上角膜缘血管大于下角膜缘血管（重复测量方差分析，p = 0.004），下角膜缘血管比上角膜缘血管更深（重复测量方差分析，p = 0.041）。上下角膜缘内角膜缘血管深度与大小之间存在正线性关联，Pearson相关系数分别为0.803和0.754。
本研究表明UHR-OCT能够成像角膜缘血管的大小和深度等形态特征。本研究结果表明角膜缘不同位置的血管在大小和深度上存在差异，这可能表明对上睑覆盖上角膜缘导致的慢性缺氧的适应性。UHR-OCT可能是评估隐形眼镜对角膜缘微血管特性影响的有用工具。
