Department of Ophthalmology, Oslo University Hospital HF, Postboks 4950 Nydalen, 0424, Oslo, Norway; Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, P.O. Box 1171 Blindern, 0318, Oslo, Norway; The Circulation Laboratory, Department of Cardiothoracic Surgery, Oslo University Hospital HF, Postboks 4950 Nydalen, 0424, Oslo, Norway.
Lerner Research Institute, Department of Biomedical Engineering, 9500 Euclid Ave, ND20, Cleveland, OH, 44195, USA.
Exp Eye Res. 2020 Dec;201:108312. doi: 10.1016/j.exer.2020.108312. Epub 2020 Oct 22.
In piglets we tested the applicability of digital video microscopy and diffuse reflectance spectroscopy for non-invasive assessments of limbal and bulbar conjunctival microcirculation. A priori we postulated that the metabolic rate is higher in limbal as compared to bulbar conjunctiva, and that this difference is reflected in microvascular structure or function between the two locations. Two study sites, Oslo University Hospital (OUH), Norway and Cleveland Clinic (CC), USA, used the same video microscopy and spectroscopy techniques to record limbal and bulbar microcirculation in sleeping piglets. Recordings were analyzed with custom-made software to quantify functional capillary density, capillary flow velocity and microvascular oxygen saturation in measuring volumes of approximately 0.1 mm. The functional capillary density was higher in limbus than in bulbar conjunctiva at both study sites (OUH: 18.1 ± 2.9 versus 12.2 ± 2.9 crossings per mm line, p < 0.01; CC: 11.3 ± 3.0 versus 7.1 ± 2.8 crossings per mm line, p < 0.01). Median categorial capillary blood flow velocity was higher in bulbar as compared with limbal recordings (CC: 3 (1-3) versus 1 (0-3), p < 0.01). Conjunctival microvascular oxygen saturation was 88 ± 5.9% in OUH versus 94 ± 7.5% in CC piglets. Non-invasive digital video microscopy and diffuse reflectance spectroscopy can be used to obtain data from conjunctival microcirculation in piglets. Limbal conjunctival microcirculation has a larger capacity for oxygen delivery as compared with bulbar conjunctiva.
在仔猪中，我们测试了数字视频显微镜和漫反射光谱学用于非侵入性评估角膜缘和球结膜微循环的适用性。我们假设代谢率在角膜缘处高于球结膜，并且这种差异反映在两个位置之间的微血管结构或功能上。两个研究地点，挪威奥斯陆大学医院（OUH）和美国克利夫兰诊所（CC），使用相同的视频显微镜和光谱技术记录睡眠仔猪的角膜缘和球结膜微循环。使用定制软件分析记录以量化功能毛细血管密度、毛细血管血流速度和测量体积（约 0.1mm）中的微血管氧饱和度。在两个研究地点，角膜缘的功能毛细血管密度均高于球结膜（OUH：18.1±2.9 与 12.2±2.9 个交叉/mm 线，p<0.01；CC：11.3±3.0 与 7.1±2.8 个交叉/mm 线，p<0.01）。与角膜缘记录相比，中值分类毛细血管血流速度在球结膜中更高（CC：3（1-3）与 1（0-3），p<0.01）。结膜微血管氧饱和度在 OUH 仔猪中为 88±5.9%，在 CC 仔猪中为 94±7.5%。非侵入性数字视频显微镜和漫反射光谱学可用于从仔猪结膜微循环中获得数据。与球结膜相比，角膜缘结膜微循环具有更大的氧气输送能力。
