Optical Imaging of Photoreceptor Function and Structure

描述（由申请人提供）：当光感受器收集并响应光时，人类的视觉就开始了。正常的光感受器功能和结构对正常的视力至关重要，但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。快速、特异和非侵入性的新型光学模式有望极大地扩展我们更准确、更全面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特性，眼底结构与波前传感的相互作用，以及光导过程。具体目标是：

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.