3D Imaging of Retinal Pigment Epithelial Cells in the Living Human Retina.
3D Imaging of Retinal Pigment Epithelial Cells in the Living Human Retina.
复制标题
DOI：
10.1167/iovs.16-19106
复制
发表时间：
2016-07-01
影响因子：
4.4
通讯作者：
Miller DT
中科院分区：
文献类型：
--
作者：
Liu Z;Kocaoglu OP;Miller DT
视网膜色素上皮（RPE）的功能障碍是许多视网膜病变的基础，但在细胞水平上对RPE变化敏感的生物标志物是有限的。在这项研究中，我们使用自适应光学相干断层扫描（AO-OCT）结合细胞器运动作为一种新的对比机制，可视化RPE细胞和表征其三维（3D）反射率分布。使用印第安纳州AO-OCT成像系统（λc = 790 nm），在6名正常受试者（25-61岁）的黄斑中采集体积。体积以亚细胞精度进行3D配准，分层分割，并提取RPE和感光细胞正面图像并取平均值。Voronoi和二维（2D）功率谱分析应用于图像，以量化RPE和锥填充和锥-RPE比。自适应光学OCT显示在RPE的深度处有两种不同的反射模式。一个特征在于RPE与视杆细胞尖端的界面，第二个特征在于RPE细胞核和周围的细胞器，可能是黑色素。通过平均化增加细胞对比度被证明对于观察RPE细胞镶嵌是关键的，在所有受试者中成功并且视网膜偏心成像。视网膜色素上皮镶嵌包装和细胞厚度一般同意的组织学和在体内研究使用其他成像方式。据我们所知，我们已经提出了第一个详细的表征的三维反射曲线的个体RPE细胞和它们的关系，锥和杆在活的人类视网膜。在年轻人和老年人眼睛中的成功为在更大的人群中测试衰老效应建立了一条道路。由于该技术基于OCT，因此我们的测量将有助于解释临床OCT图像。
Dysfunction of the retinal pigment epithelium (RPE) underlies numerous retinal pathologies, but biomarkers sensitive to RPE change at the cellular level are limited. In this study, we used adaptive optics optical coherence tomography (AO-OCT) in conjunction with organelle motility as a novel contrast mechanism to visualize RPE cells and characterize their 3-dimensional (3D) reflectance profile. Using the Indiana AO-OCT imaging system (λc = 790 nm), volumes were acquired in the macula of six normal subjects (25–61 years). Volumes were registered in 3D with subcellular accuracy, layers segmented, and RPE and photoreceptor en face images extracted and averaged. Voronoi and two-dimensional (2D) power spectra analyses were applied to the images to quantify RPE and cone packing and cone-to-RPE ratio. Adaptive optics OCT revealed two distinct reflectance patterns at the depth of the RPE. One is characterized by the RPE interface with rod photoreceptor tips, the second by the RPE cell nuclei and surrounding organelles, likely melanin. Increasing cell contrast by averaging proved critical for observing the RPE cell mosaic, successful in all subjects and retinal eccentricities imaged. Retinal pigment epithelium mosaic packing and cell thickness generally agreed with that of histology and in vivo studies using other imaging modalities. We have presented, to our knowledge, the first detailed characterization of the 3D reflectance profile of individual RPE cells and their relation to cones and rods in the living human retina. Success in younger and older eyes establishes a path for testing aging effects in larger populations. Because the technology is based on OCT, our measurements will aid in interpreting clinical OCT images.