Ni Shuibin, Khan Shanjida, Nguyen Thanh-Tin P, Ng Ringo, Lujan Brandon J, Tan Ou, Huang David, Jian Yifan
Casey Eye Institute, Oregon Health & Science University, Portland, Oregon 97239, USA.
Department of Biomedical Engineering, Oregon Health & Science University, Portland, Oregon 97239, USA.
Biomed Opt Express. 2022 Jan 21;13(2):950-961. doi: 10.1364/BOE.447882. eCollection 2022 Feb 1.
Photoreceptor loss and resultant thinning of the outer nuclear layer (ONL) is an important pathological feature of retinal degenerations and may serve as a useful imaging biomarker for age-related macular degeneration. However, the demarcation between the ONL and the adjacent Henle's fiber layer (HFL) is difficult to visualize with standard optical coherence tomography (OCT). A dedicated OCT system that can precisely control and continuously and synchronously update the imaging beam entry points during scanning has not been realized yet. In this paper, we introduce a novel imaging technology, Volumetric Directional OCT (VD-OCT), which can dynamically adjust the incident beam on the pupil without manual adjustment during a volumetric OCT scan. We also implement a customized spoke-circular scanning pattern to observe the appearance of HFL with sufficient optical contrast in continuous cross-sectional scans through the entire volume. The application of VD-OCT for retinal imaging to exploit directional reflectivity properties of tissue layers has the potential to allow for early identification of retinal diseases.
光感受器丧失以及由此导致的外核层（ONL）变薄是视网膜变性的一个重要病理特征，并且可能作为年龄相关性黄斑变性的一种有用的成像生物标志物。然而，使用标准光学相干断层扫描（OCT）很难看清ONL与相邻的Henle纤维层（HFL）之间的界限。一种能够在扫描过程中精确控制并连续同步更新成像光束入射点的专用OCT系统尚未实现。在本文中，我们介绍了一种新型成像技术，即体层定向OCT（VD-OCT），它能够在体层OCT扫描期间无需手动调整即可动态调整瞳孔上的入射光束。我们还实施了一种定制的辐条-圆形扫描模式，以便在通过整个体积的连续横断面扫描中以足够的光学对比度观察HFL的外观。将VD-OCT应用于视网膜成像以利用组织层的定向反射特性，有可能实现视网膜疾病的早期识别。
