To elucidate the molecular pathogenesis of age-related macular degeneration (AMD) and interpretation of fundus autofluorescence imaging, the authors identified spectral autofluorescence characteristics of drusen and retinal pigment epithelium (RPE) in donor eyes with AMD.
Macular RPE/Bruch membrane flat mounts were prepared from 5 donor eyes with AMD. In 12 locations (1–3 per eye), hyperspectral autofluorescence images in 10-nm-wavelength steps were acquired at 2 excitation wavelengths (λex 436, 480 nm). A nonnegative tensor factorization algorithm was used to recover 5 abundant emission spectra and their corresponding spatial localizations.
At λex 436 nm, the authors consistently localized a novel spectrum (SDr) with a peak emission near 510 nm in drusen and sub-RPE deposits. Abundant emission spectra seen previously (S0 in Bruch membrane and S1, S2, and S3 in RPE lipofuscin/melanolipofuscin, respectively) also appeared in AMD eyes, with the same shapes and peak wavelengths as in normal tissue. Lipofuscin/melanolipofuscin spectra localizations in AMD eyes varied widely in their overlap with drusen, ranging from none to complete.
An emission spectrum peaking at ∼510 nm (λex 436 nm) appears to be sensitive and specific for drusen and sub-RPE deposits. One or more abundant spectra from RPE organelles exhibit characteristic relationships with drusen.
Hyperspectral autofluorescence images of retinal pigment epithelium/Bruch membrane flat mounts were acquired and analyzed using a nonnegative tensor factorization algorithm. Five abundant emission spectra and their corresponding spatial localizations were recovered. An emission spectrum peaking at 510 nm appears to be sensitive and specific for drusen and sub–retinal pigment epithelium deposits.
*Department of Ophthalmology, New York University School of Medicine, New York, New York;
†Department of Computer Science and Engineering, New York University Tandon School of Engineering, Brooklyn, New York;
‡Leibniz Institute of Photonic Technology, Jena, Germany;
§Institute of Physical Chemistry and Abbe Center of Photonics, Friedrich Schiller University of Jena, Jena, Germany;
¶Department of Ophthalmology, Medical University of South Carolina, Charleston, South Carolina;
**Department of Ophthalmology, University of Alabama School of Medicine, Birmingham, Alabama; and
††Department of Ophthalmology, University Hospital of Würzburg, Würzburg, Germany.
Reprint requests: R. Theodore Smith, MD, PhD, Department of Ophthalmology, New York University School of Medicine, 462 First Avenue, NBV 5N18, New York, NY 10016; e-mail: email@example.com
Supported by the National Institutes of Health/National Eye Institute (Bethesda, MD) grants R01 EY019065 (Z.A.), EY06109 (C.A.C.), EY015520 (R.T.S.), and EY021470 (R.T.S.); a Foundation Fighting Blindness (Columbia, MD) Individual Investigator Research Award (R.T.S.); unrestricted funds from Research to Prevent Blindness (New York, NY) (Z.A., C.A.C., R.T.S.); International Society for Eye Research (San Francisco, CA) 2014 von Sallmann Prize (C.A.C.); EyeSight Foundation of Alabama (Birmingham, AL) (C.A.C.); and German Research Foundation (Bonn, Germany) grants DFG Ac265/1-1 and DFG Ac265/2-1 (T.B.A.).
C. A. Curcio is a consultant to Genentech (South San Francisco, CA), Novartis (Basel, Switzerland), Merck (Kenilworth, NJ), and Janssen Cell Therapy (Spring House, PA). R. T. Smith is a consultant to Ocata Therapeutics (Marlborough, MA). Remaining authors have no conflicting interests to disclose.
The study was performed at New York University School of Medicine, New York, New York.
Drs. Thomas Ach and R. Theodore Smith share joint senior authorship.