Akiba Masahiro, Maeda Naoyuki, Yumikake Kazuhiko, Soma Takeshi, Nishida Kohji, Tano Yasuo, Chan Kin Pui
Yamagata Promotional Organization for Industrial Technology, Yamagata, Japan.
J Biomed Opt. 2007 Jul-Aug;12(4):041202. doi: 10.1117/1.2764461.
A feasibility study of ultrahigh-resolution full-field optical coherence tomography (FF-OCT) for a subcellular-level imaging of human donor corneas is presented. The FF-OCT system employed in this experiment is based on a white light interference microscope, where the sample is illuminated by a thermal light source and a horizontal cross-sectional (en face) image is detected using a charge coupled device (CCD) camera. A conventional four-frame phase-shift detection technique is employed to extract the interferometric image from the CCD output. A 95-nm-broadband full-field illumination yields an axial resolution of 2.0 microm, and the system covers an area of 850 microm x 850 microm with a transverse resolution of 2.4 microm using a 0.3-NA microscope objective and a CCD camera with 512 x 512 pixels. Starting a measurement from the epithelial to the endothelial side, a series of en face images was obtained. From detected en face images, the epithelial cells, Bowman's layer, stromal keratocyte, nerve fiber, Descemet's membrane, and endothelial cell were clearly observed. Keratocyte cytoplasm, its nuclei, and its processes were also separately detected. Two-dimensional interconnectivity of the keratocytes is visualized, and the keratocytes existing between collagen lamellaes are separately extracted by exploiting a high axial resolution ability of FF-OCT.
本文介绍了超高分辨率全场光学相干断层扫描（FF-OCT）用于人类供体角膜亚细胞水平成像的可行性研究。本实验中使用的FF-OCT系统基于白光干涉显微镜，其中样品由热光源照明，并使用电荷耦合器件（CCD）相机检测水平横截面（正面）图像。采用传统的四帧相移检测技术从CCD输出中提取干涉图像。95纳米宽带全场照明产生2.0微米的轴向分辨率，该系统使用0.3数值孔径的显微镜物镜和512×512像素的CCD相机，覆盖面积为850微米×850微米，横向分辨率为2.4微米。从上皮侧到内皮侧开始测量，获得了一系列正面图像。从检测到的正面图像中，可以清晰地观察到上皮细胞、Bowman层、基质角膜细胞、神经纤维、Descemet膜和内皮细胞。角膜细胞的细胞质、细胞核及其突起也被分别检测到。通过利用FF-OCT的高轴向分辨率能力，可视化了角膜细胞的二维连通性，并分别提取了胶原板层之间存在的角膜细胞。
