高速全域式光學同調斷層掃描術於活體皮膚及角膜影像分析

In Vivo Skin and Cornea Using High-speed Mirau-based Full-field Optical Coherence Tomography

林政廷(Jheng-Ting Lin)

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(2019年)

https://doi.org/10.6342/NTU201904031

摘要

在皮膚及角膜的醫療診斷上，若能同時提供疾病橫向以及縱向上影像，有助於判斷確切的病理位置、結構以及細胞形貌。全域式光學同調斷層掃描術是一種時域式光學同調斷層掃描術，主要是移動PZT線性平台來掃描樣本不同深度的影像，通過二維相機來擷取二維影像，來構建出三維斷層影像，且其掃描速度取決於相機的畫面更新率。如今，大多數全域式光學同調斷層掃描術的掃描速度太慢，於掃描樣本組織上會花費太多時間，容易因為樣本或環境的振動導致影像品質變差。
本論文利用擁有高空間解析度的Mirau-based全域式光學同調斷層掃描系統並搭配畫面更新率為1051 fps的高速相機來量測活體人類皮膚與大鼠角膜，其影像大小分別為960x960x897 pixels以及960x960x574 pixels，掃描時間僅需3.6秒以及2.4秒。在高空間解析度以及高速掃描下，活體人體皮膚與大鼠角膜的組織結構可以被清楚解析，例如皮膚表皮層與真皮層交界、角膜各層分界、組織細胞邊界與形貌，此外針對角膜內皮細胞的密度也可量化出來，約2384±278 cell/mm2。藉由高速的量測，位於微血管中的單顆紅血球流動變化也可被觀測，並且計算紅血球流速，約95.54±27.82 μm/s。
在醫療上，本論文中所展示的高速Mirau-based全域式光學同調斷層掃描系統，不僅能提供在橫向及縱向上的高解析度影像，也能夠大幅縮短量測樣本時間，並可減少在量測上環境的震動影像。

關鍵字

高速Mirau-based全域式光學同調斷層掃描系統 ； 皮膚 ； 角膜 ； 角膜內皮細胞密度 ； 紅血球流速

並列摘要

For precise diagnosis skin and cornea pathology, en face and cross-section images are required to determine the exact pathological position, structure and cell morphology at the same time. Full-field optical coherence tomography (FF-OCT) is a kind of time-domain OCT, that scans different depth of tissues by moving PZT linear stage and collects 2-D images by camera to construct 3-D tomogram in real time. The scanning speed is depended on the frame rate of camera. Nowadays, the scanning speed of most FF-OCT are too slow, so scanning tissue will spend too much time and image quality may be worse by vibration from tissue or environment.
Using high-resolution Mirau-based FF-OCT with high-speed CMOS, which frame rate is 1051 fps, 960x960x897 pixels of in vivo human skin and 960x960x574 pixels of in vivo rat cornea were scanning in 3.6 s and 2.4 s, respectively. With high spatial resolution and high-speed scanning, the structure of skin and cornea could be distinguished clearly, such like skin dermis-epidermis junction (DEJ), different corneal layers, cell morphology and boundary. The endothelium cell density of rat cornea was quantified as 2384±278 cell/mm2. Movement of single red blood cell (RBC) in microvessel could be detected, and the velocity could also be calculated as 95.54±27.82 μm/s by high-speed measurement.
The high-speed Mirau-based FF-OCT not only can provide high quality lateral and axial images, but also can significantly reduce scanning time to reduce the vibration from tissue or environment.

並列關鍵字

high-speed Mirau-based full-field optical coherence tomography ； skin ； cornea ； endothelium cell density ； red blood cell velocity

參考文獻

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