title: Imaging individual neurons in the retinal ganglion cell layer of the living eye.
abstract: Although imaging of the living retina with adaptive optics scanning light ophthalmoscopy (AOSLO) provides microscopic access to individual cells, such as photoreceptors, retinal pigment epithelial cells, and blood cells in the retinal vasculature, other important cell classes, such as retinal ganglion cells, have proven much more challenging to image. The near transparency of inner retinal cells is advantageous for vision, as light must pass through them to reach the photoreceptors, but it has prevented them from being directly imaged in vivo. Here we show that the individual somas of neurons within the retinal ganglion cell (RGC) layer can be imaged with a modification of confocal AOSLO, in both monkeys and humans. Human images of RGC layer neurons did not match the quality of monkey images for several reasons, including safety concerns that limited the light levels permissible for human imaging. We also show that the same technique applied to the photoreceptor layer can resolve ambiguity about cone survival in age-related macular degeneration. The capability to noninvasively image RGC layer neurons in the living eye may one day allow for a better understanding of diseases, such as glaucoma, and accelerate the development of therapeutic strategies that aim to protect these cells. This method may also prove useful for imaging other structures, such as neurons in the brain.
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642; rossiea@pitt.edu.
authors.forename: Ethan A
authors.initials: EA
authors.lastname: Rossi
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.|The Institute of Optics, University of Rochester, Rochester, NY 14620.
authors.forename: Charles E
authors.initials: CE
authors.lastname: Granger
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.
authors.forename: Robin
authors.identifier: 0000-0002-0761-3227
authors.initials: R
authors.lastname: Sharma
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Canon USA, Inc., Melville, NY 11747.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Saito
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.
authors.forename: Christina
authors.initials: C
authors.lastname: Schwarz
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.|The Institute of Optics, University of Rochester, Rochester, NY 14620.
authors.forename: Sarah
authors.initials: S
authors.lastname: Walters
authors.affiliation: Canon USA, Inc., Melville, NY 11747.
authors.forename: Koji
authors.initials: K
authors.lastname: Nozato
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Canon USA, Inc., Melville, NY 11747.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Kawakami
authors.affiliation: Flaum Eye Institute, University of Rochester Medical Center, Rochester, NY 14642.
authors.forename: William
authors.initials: W
authors.lastname: Fischer
authors.affiliation: Flaum Eye Institute, University of Rochester Medical Center, Rochester, NY 14642.
authors.forename: Lisa R
authors.initials: LR
authors.lastname: Latchney
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.|Flaum Eye Institute, University of Rochester Medical Center, Rochester, NY 14642.
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Hunter
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.|Flaum Eye Institute, University of Rochester Medical Center, Rochester, NY 14642.
authors.forename: Mina M
authors.initials: MM
authors.lastname: Chung
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, NY 14642.|The Institute of Optics, University of Rochester, Rochester, NY 14620.
authors.forename: David R
authors.initials: DR
authors.lastname: Williams
mesh_terms: D000818:Animals; D005260:Female; D005901:Glaucoma / Q000000981:diagnostic imaging; D006801:Humans; D008252:Macaca fascicularis / Q000033:anatomy & histology; D008253:Macaca mulatta / Q000033:anatomy & histology; D008268:Macular Degeneration / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D009887:Ophthalmoscopy / Q000379:methods*; D055620:Optical Phenomena; D017949:Retinal Cone Photoreceptor Cells / Q000166:cytology; D012165:Retinal Ganglion Cells / Q000166:cytology*; D013045:Species Specificity
keywords: adaptive optics; imaging; photoreceptors; retina; retinal ganglion cells