Optical Imaging of Photoreceptor Function and Structure

描述(申请人提供)：当光感受器收集光并对光做出反应时，人类视觉开始。正常的光感受器功能和结构对正常视力是必不可少的，然而在体内评估这些功能和结构的技术是有限的。目前的光学和电生理学方法具有有限的空间分辨率和灵敏度，并且仅针对特定的功能过程。新的光学模式是快速、特异和非侵入性的，有望极大地扩展我们更准确和更完整地监测光感受器功能和结构的能力。我们将使用自适应光学(AO)和光谱域光学相干断层扫描(SD-OCT)在细胞尺度上对人类视网膜进行非侵入性成像。我们将研究光感受器的波导性，眼底结构与波前传感的相互作用，以及光传导过程。具体目标是： (1.)评估中央和外周视网膜光感受器光波导的解剖学起源和功能意义。这将通过使用SD-OCT的假设驱动研究来实现。 (2)建立了人体眼底作为厚反射层的定量光学模型，该模型考虑了眼底结构对波前传感精度和精确度的影响。SD-OCT将被用来检验这样的假设，即如果不控制轴向伸长和随着眼底反射的光瞳位置的变化而导致波前测量误差。 (3)通过测量光感受器散射特性的光诱发变化，评估AO和SD-OCT作为非侵入性光学方法测量光传导功能机制的潜力。 这项研究的长期目标是建立先进的光学技术，用于非侵入性地探测人类视网膜的细胞功能和结构。这些技术将用于研究体内的光感受器，一旦建立，将有望改进对影响这些细胞的疾病的早期检测和治疗监测。

DESCRIPTION (provided by applicant): Human vision starts when photoreceptors collect and respond to light. Normal photoreceptor function and structure are essential for normal vision, yet techniques to assess these in vivo are limited. Current optical and electrophysiological approaches have limited spatial resolution and sensitivity, and target only specific functional processes. New optical modalities that are rapid, specific, and non-invasive hold the promise of greatly expanding our capability to monitor more accurately and completely photoreceptor function and structure. We will use adaptive optics (AO) and spectral-domain optical coherence tomography (SD-OCT) to non-invasively image the human retina at the cellular scale. We will study the waveguide properties of photoreceptors, the interaction of fundus structure with wavefront sensing, and the phototransduction process. The specific aims are to: (1.) Evaluate the anatomical origins and functional implications of optical waveguiding by photoreceptors in central and peripheral retina. This will be achieved in a hypothesis driven study using SD-OCT. (2.) Develop a quantitative optical model of the human fundus as a thick reflector that accounts for the impact of fundus structure on accuracy and precision of wavefront sensing. SD-OCT will be used to test the hypothesis that axial elongation and variation with pupil position of the fundus reflection leads to wavefront measurement errors if not controlled. (3.) Evaluate the potential of AO and SD-OCT as non-invasive, optical methods for measuring functional mechanisms of phototransduction by measuring light-evoked changes in the scattering properties of photoreceptors. The long term goal of this research is to establish advanced optical techniques for non-invasive probing of cellular function and structure in the human retina. These techniques will be used to study photoreceptors in vivo, and once established will promise improvements in early detection and treatment monitoring for diseases that impact these cells.