title: A Novel, Real-Time, In Vivo Mouse Retinal Imaging System.
abstract: OBJECTIVE
  To develop an efficient, low-cost instrument for robust real-time imaging of the mouse retina in vivo, and assess system capabilities by evaluating various animal models.
  
  
  METHODS
  Following multiple disappointing attempts to visualize the mouse retina during a subretinal injection using commercially available systems, we identified the key limitation to be inadequate illumination due to off axis illumination and poor optical train optimization. Therefore, we designed a paraxial illumination system for Greenough-type stereo dissecting microscope incorporating an optimized optical launch and an efficiently coupled fiber optic delivery system. Excitation and emission filters control spectral bandwidth. A color coupled-charged device (CCD) camera is coupled to the microscope for image capture. Although, field of view (FOV) is constrained by the small pupil aperture, the high optical power of the mouse eye, and the long working distance (needed for surgical manipulations), these limitations can be compensated by eye positioning in order to observe the entire retina.
  
  
  RESULTS
  The retinal imaging system delivers an adjustable narrow beam to the dilated pupil with minimal vignetting. The optic nerve, vasculature, and posterior pole are crisply visualized and the entire retina can be observed through eye positioning. Normal and degenerative retinal phenotypes can be followed over time. Subretinal or intraocular injection procedures are followed in real time. Real-time, intravenous fluorescein angiography for the live mouse has been achieved.
  
  
  CONCLUSIONS
  A novel device is established for real-time viewing and image capture of the small animal retina during subretinal injections for preclinical gene therapy studies.
authors.affiliation: Research Service, VA Western New York Healthcare System, Buffalo, New York, United States 2Department of Ophthalmology, Ross Eye Institute, University at Buffalo-SUNY, Buffalo, New York, United States.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Butler
authors.affiliation: Research Service, VA Western New York Healthcare System, Buffalo, New York, United States 2Department of Ophthalmology, Ross Eye Institute, University at Buffalo-SUNY, Buffalo, New York, United States 3Department of Pharmacology/Toxicology, University at.
authors.forename: Jack M
authors.initials: JM
authors.lastname: Sullivan
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004867:Equipment Design; D005451:Fluorescein Angiography / Q000295:instrumentation*; D005654:Fundus Oculi; D051379:Mice; D008810:Mice, Inbred C57BL; D008853:Microscopy / Q000295:instrumentation*; D012160:Retina / Q000473:pathology*; D012162:Retinal Degeneration / Q000175:diagnosis*