A novel method for volumetric oxygen mapping in living retina

项目摘要 人们普遍认为，缺氧是几种主要视网膜疾病的罪魁祸首和标志， 包括糖尿病视网膜病变、老年性黄斑变性、青光眼等。然而， 在眼睛中测量体内氧气极具挑战性，并且目前不存在可以提供3D测量的工具。 在适当的成像速度下以高空间分辨率测量视网膜中的氧分布。这个目标 本项目旨在克服这些局限性，并开发一种新的体积氧光学成像技术 在视网膜上映射。我们的方法将利用最近开发的有效氧探头（如Oxyphor 2 P），其磷光衰减时间用作局部氧分压（pO 2）的定量标记 在活组织中。为了实现高通量的体积成像，我们提出开发一种新的成像方法， 仪器，称为倾斜扫描激光检眼镜（奥斯陆）。奥斯陆是基于单 透镜扫描光片显微镜，并使体积磷光寿命成像没有时间- 消耗逐平面的逐像素切片。我们的新方法应该能够实现10千赫体素 比目前最先进的双光子磷光高三个数量级 寿命显微镜（2 PLM）。在本项目中，我们将：（目标1）开发基于磷光寿命的奥斯陆 用于小鼠活体视网膜的体积pO 2绘图。新的设计将允许并行检测信号， 从每个扫描位置的深度，从而消除了传统的深度切片的需要， 吞吐量大大增加。我们将（目的2）动态成像视网膜和脉络膜对系统性 缺氧挑战使用Oxyphor 2 P。我们将（目标3）然后桥接奥斯陆测量和无标签 通过使用可见光光学相干断层扫描（vis-OCT）的多模态成像来实现这些应用。使用血管 pO 2作为地面实况，我们将开发一种深度频谱训练（DSL）算法来监督逆 vis-OCT的计算，用于稳健和可靠的无标记视网膜血氧饱和度测定。这项研究将使第一个直接 视网膜中两个循环系统（即视网膜和脉络膜）之间相互作用的定量成像 循环），提供了前所未有的信息视网膜氧气供应。对公众健康的影响： 该计划的成功完成将提供一个新的突破性的方法来绘制氧气， 这将大大提高我们对视网膜疾病的理解。

PROJECT SUMMARY It is widely accepted that oxygen deficiency is a culprit and a marker of several major retinal diseases, including diabetic retinopathy, age-related macular degeneration, glaucoma etc. However, it remains to be extremely challenging to measure oxygen in vivo in the eye, and no tools currently exist that can provide 3D oxygen distributions in the retina with high spatial resolution at appropriate imaging speeds. The goal of this project is to overcome these limitations and develop a new optical imaging technique for volumetric oxygen mapping in retina. Our approach will leverage the recently developed potent oxygen probes (such as Oxyphor 2P), whose phosphorescence decay times serve as quantitative markers of local oxygen partial pressures (pO2) in living tissues. To enable volumetric imaging with high throughput, we propose to develop a novel imaging instrument, termed oblique scanning laser ophthalmoscope (oSLO). oSLO is based on the concept of single lens scanned light sheet microscopy and enables volumetric phosphorescence lifetime imaging without time- consuming plane-by-plane pixel-wise sectioning. Our new method should be able to achieve 10 kilohertz voxel rate that is three orders of magnitude higher than the current state-of-the-art two-photon phosphorescence lifetime microscopy (2PLM). In this project we will: (Aim 1) develop a phosphorescence lifetime-based oSLO for volumetric pO2 mapping in living retina in mouse. The new design will allow parallel detection of signals at depth from each scanned location, so that the need in conventional depth sectioning is eliminated and imaging throughput is greatly increased. We will (Aim 2) dynamically image responses of retina and choroid to systemic hypoxia challenge using Oxyphor 2P. We will (Aim 3) then bridge oSLO measurements and label-free applications by multimodal imaging with visible light optical coherence tomography (vis-OCT). Using vascular pO2 as the ground-truth, we will develop a deep spectral training (DSL) algorithm to supervise the inverse calculation of vis-OCT for robust and reliable label-free retinal oximetry. This study will enable the first direct quantitative imaging of interactions between the two circulatory systems in retina (i.e. retinal and choroidal circulation), providing unprecedented information about retinal oxygen supply. IMPACT ON PUBLIC HEALTH: Successful completion of this program will deliver a new ground-breaking methodology for mapping oxygen in the retina that will greatly improve our understanding of retinal diseases.