High-Resolution Functional Imaging of the Retina

项目摘要 我们希望了解维持人类视觉的两个重要过程；视觉周期是 负责再生因吸收可见光和细胞而漂白的感光颜料 每个活细胞都需要新陈代谢来提供能量。为了研究这些过程，我们需要一个 方法将单个细胞可视化，并测量活眼的分子动力学。其中一些 涉及的分子本质上是荧光的，但在活着的眼睛中是无法接触到的 光子荧光成像，因为激发落在辐射范围之外，可以 穿透眼睛的光学系统。通过使用相当长的激发波长，双光子 激发的荧光成像有可能激发这些原本无法获得的荧光团 并为成像许多视网膜结构提供本征对比度。在我们最初的实验中，我们 使用自适应光学扫描光检眼镜(AOSLO)成像双光子荧光 从活着的猕猴眼睛的锥体内节(Hunter等人，2011年)。通过更正 眼睛的纵向色差和物质弥散，我们计划提高效率 我们的成像系统，并开发方法，以可靠地成像结构和功能 眼睛里有多层视网膜。这一能力不仅提供了对正常细胞马赛克的洞察 以及它们的生化过程，这也将提高我们对许多影响 这些视网膜生化级联反应如Stargardt病、黄斑变性和Leber病 遗传性视神经病变。

Project Summary We wish to understand two important processes that sustain human vision; the visual cycle is responsible for regeneration of photopigment bleached by absorption of visible light and cellular metabolism is required in every living cell to provide energy. To study these processes, we need a method to visualize individual cells and measure molecular dynamics in the living eye. Some of the molecules involved are intrinsically fluorescent, but are inaccessible in the living eye with single- photon fluorescence imaging because the excitation falls outside the range of radiation that can penetrate the optics of the eye. By using considerably longer excitation wavelengths, two-photon excited fluorescence imaging has the potential to excite these otherwise inaccessible fluorophores and provide intrinsic contrast for imaging a number of retinal structures. In our initial experiments, we used an adaptive optics scanning light ophthalmoscope (AOSLO) to image two-photon fluorescence from cone inner segments in the living macaque eye (Hunter et al, 2011). By correcting the longitudinal chromatic aberration and material dispersion of the eye, we plan to improve the efficiency of our imaging systems and develop methodology for reliably imaging both structure and function of multiple retinal layers in the eye. Not only will this capability provide insight into normal cell mosaics and their biochemical processes, it will also improve our understanding of many diseases that impact these retinal biochemical cascades such as Stargardt's disease, macular degeneration and Leber's hereditary optic neuropathy.