全域式光學同調斷層掃描術用於動物眼睛模型之特性分析

Animal Eye Models Using Full-field Optical Coherence Tomography

陳昱彤(Yu-Tung Chen)

指導教授 ： 黃升龍

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2018年)

https://doi.org/10.6342/NTU201802457

摘要

在醫療上，能提供三維角膜結構影像，並且將疾病所在位置之橫平面與縱平面的影像同時呈現出來，對於準確診斷角膜病理或是辨識不同角膜組織細胞形態，將會是強而有利的證據。例如一些較特別的組織：Vogt柵欄(palisade of Vogt; POV)、新生血管、角膜神經等等角膜組織或病理，影像上若只用一個維度去呈現，較難展現結構型態。
在本研究中，利用具有等向性之次微米等級空間解析度的全域式光學同調斷層掃描術展示角膜結構橫平面影像、兩個縱平面影像與三維影像。本系統也具有大面積掃描模式，影像分析上，能夠將相鄰的三維立體結構拼接起來重建成大範圍三維影像圖。藉由活體大鼠與兔子實驗，證實本系統的成像能力能夠用來計算角膜特性，例如角膜各層厚度、細胞密度、不同結構的強度分布。計算結果，大鼠角膜各組織平均厚度分別為：上皮細胞層54.1±4.0 μm、前彈力層至基質層97.4±5.0 μm、後彈力層5.9±0.8 μm、內皮細胞層1.7±0.3 μm。另外，本論文也量化大鼠內皮細胞之細胞密度，大約2211±166 mm-2。
本論文利用全域式光學同調斷層掃描術可將大鼠眼睛山脊狀的POV結構、角膜神經分支與結膜血管的影像辨識出來。並且也能清楚呈現活體兔子新生血管疾病角膜模型中血管管壁與紅血球影像，此全域式光學同調斷層掃描術研究有望能促進角膜疾病診斷與治療。

關鍵字

全域式光學同調斷層掃描術 ； 角膜 ； 角膜緣 ； 結膜 ； 角膜新生血管 ； Vogt柵欄

並列摘要

Accurate diagnosis of corneal pathology and morphological identification of different corneal layers require clear delineation of corneal three-dimensional structures and en face or cross-sectional imaging of palisade of Vogt (POV), neovascularization or corneal nerves. Here we report a prototype of full-field optical coherent tomography (FF-OCT) system with isotropic sub-micron spatial resolution in the en face and cross-sectional views. It can also provide three-dimensional reconstructed images and a large field of view by stitching tomograms side by side. We validated the imaging power of this prototype in in vivo rat and rabbit eyes, and quantified anatomical characteristics such as corneal layer thickness, endothelial cell density and the intensity profile of different layers. The mean thicknesses of rat corneal epithelium, Bowman-to-stroma, Descemet’s membrane, and endothelium were 54.1±4.0 μm, 97.4±5.0 μm, 5.9±0.8 μm, and 1.7±0.3 μm, respectively. The cell density of rat polygonal endothelial cells was quantified to be 2211±166 per mm2. This FF-OCT delineated the ridge-like structure of POV, corneal nerve bundles, and conjunctival vessels in rat eyes. It also clearly identified the vessel walls and red blood cells in rabbit model of corneal neovascularization (NV). The findings provided by this FF-OCT are expected to facilitate corneal disease diagnosis and treatment.

並列關鍵字

full-field optical coherent tomography ； cornea ； limbus ； conjunctiva ； corneal neovascularization ； palisade of Vogt

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