title: High-resolution retinal imaging of cone-rod dystrophy.
abstract: OBJECTIVE
  This study examines a patient with cone-rod dystrophy using high-resolution adaptive optics retinal imaging. Conventional ophthalmoscopes provide limited resolution due to their inability to overcome the eye's optical aberrations. In contrast, adaptive optics ophthalmoscopes correct these aberrations to provide noninvasive high-resolution views of the living retina. To date, adaptive optics ophthalmoscopy has been used mainly to examine the normal retina. Here we use adaptive optics ophthalmoscopy to image cone-rod dystrophy in vivo and compare these results with standard clinical tests.
  
  
  METHODS
  Observational case report.
  
  
  METHODS
  High-resolution retinal images of a patient with cone-rod dystrophy were obtained with the University of Rochester adaptive optics flood-illuminated ophthalmoscope and the adaptive optics scanning laser ophthalmoscope located at the University of Houston and compared with standard clinical tests, including fundus photography, Goldmann visual fields, fluorescein angiography, optical coherence tomography, electroretinography, and multifocal electroretinography.
  
  
  METHODS
  Direct measurement of cone density and diameter and comparison of adaptive optics images with standard clinical imaging and functional tests.
  
  
  RESULTS
  Adaptive optics images were acquired at multiple retinal locations throughout a clinically detected bull's-eye lesion. Within the atrophic regions, we observed large areas devoid of wave-guiding cones. In contrast, regions that appeared relatively spared by clinical examination contained a completely tiled cone mosaic. However, in these areas the cones were abnormally large, resulting in a 6.6-fold reduction from the normal peak cone density (patient peak density: 30 100 cones/mm2, normal peak density: 199 200 cones/mm2). Multifocal electroretinography confirmed a 5.5-fold reduction in amplitude of the central peak (10.8 nanovolts/degree2 vs. 59.8 nanovolts/degree2).
  
  
  CONCLUSIONS
  Adaptive optics ophthalmoscopy is a noninvasive technique to observe a patient's retinal pathology directly at a cellular level. It can provide a quantitative measurement of photoreceptor loss in retinal disease.
authors.affiliation: Center for Visual Science, University of Rochester, Rochester, New York 14627, USA.
authors.forename: Jessica I
authors.initials: JI
authors.lastname: Wolfing
authors.forename: Mina
authors.initials: M
authors.lastname: Chung
authors.forename: Joseph
authors.initials: J
authors.lastname: Carroll
authors.forename: Austin
authors.initials: A
authors.lastname: Roorda
authors.forename: David R
authors.initials: DR
authors.lastname: Williams
mesh_terms: D000328:Adult; D002452:Cell Count; D003952:Diagnostic Imaging / Q000379:methods; D004596:Electroretinography; D005260:Female; D005451:Fluorescein Angiography; D005654:Fundus Oculi; D006801:Humans; D009887:Ophthalmoscopy / Q000379:methods*; D020419:Photoreceptor Cells, Vertebrate / Q000473:pathology*; D012162:Retinal Degeneration / Q000175:diagnosis* / Q000503:physiopathology; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields / Q000502:physiology