Imaging Single Cells in the Living Retina

Abstract

A quarter century ago, we were limited to a macroscopic view of the retina inside the living eye. Since then, new imaging technologies, including confocal scanning laser ophthalmoscopy, optical coherence tomography, and adaptive optics fundus imaging, transformed the eye into a microscope in which individual cells can now be resolved noninvasively. These technologies have enabled a wide range of studies of the retina that were previously impossible. Keywordsretinal imaging; confocal scanning laser ophthalmoscope; adaptive optics; optical coherence tomography; spatial resolution; ophthalmoscopy The ability to look inside the living human eye is central to our understanding of how the normal eye works and the diseased eye fails. This article focuses on technological advances in the spatial resolution of retinal imaging during the last quarter century and some of the scientific discoveries they have made possible. These advances have transformed retinal imaging from a macroscopic to a microscopic modality in which individual cells can now be resolved. There are many books and review articles that address these advances. Relevant books include Masters, 2001;Porter et al, 2006; Schulman et al., 2004) and review articles include (Costa, et al., 2006;Drexler and Fujimoto, 2008;Fujimoto, 2003;Godara et al., 2010;Hampson, 2008;Miller et al., 2011;Miller and Roorda, 2009; Mojtkowski, 2010;Podoleanu, 2005;Podoleanu and Rosen, 2008;Roorda, 2010; Rossi et al. 2011;and Wilt et al., 2009).It has never been easy to peer inside the living eye. Though several investigators in the 19 th century were aware of the illumination conditions necessary to cause the otherwise impenetrable pupil to glow red, they failed to obtain a clear view of the living retina until Helmholtz invented the ophthalmoscope (Helmholtz, 1851). Since then, the evolution of this instrument has been punctuated by important, if occasional, technical advances such as adding a camera that could record retinal images on film (Jackman and Webster, 1886).© 2011 Elsevier Ltd. All rights reserved.Corresponding Author: David Williams. Conflict of Interest Disclosure: My employer, the University of Rochester, holds intellectual property on which I am an inventor and that pertain to the subject matter of this article.Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author ManuscriptVision Res. Author manuscript; available in PMC 2012 July 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author ManuscriptSurprisingly, before the late 1980's there were few improvements in optical resolution sin...

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