title: Rodent model of nonarteritic ischemic optic neuropathy and its electrophysiological evaluation.
abstract: OBJECTIVE
  Our aim was to establish a rodent model of nonarteritic ischemic optic neuropathy (rNAION).
  
  
  METHODS
  To induce rNAION, after administration of Rose Bengal (RB) (2.5 mM), the small vessels of the left optic nerve were photoactivated using a 514-nm argon green laser with about 500-μm spot size for 12 s (RB-laser induction). To evaluate the induction, funduscopic examination, fluorescein angiography (FA), visualization of capillaries within the optic disc, histologic evaluation, and electrophysiological testing were performed.
  
  
  RESULTS
  In the RB-laser-induction eyes, the optic disc became swollen on day 3 followed by atrophy on week 8. FA showed filling defects in the choroid and optic disc at an early stage, followed by hyperfluorescence at a late stage. The capillaries within the optic disc were reduced markedly. Histopathologic examination showed acellular nerve fiber layer (NFL) swelling anterior to the optic disc. The morphologic retinal changes were apparent only in the retinal ganglion cell (RGC) layer, with a reduction in the number of cells. Visually evoked potential (VEP) amplitude decreased significantly, but electroretinography (ERG) showed no significant difference. The positive scotopic threshold response (pSTR) was not reduced on the 1st day but was significantly reduced 3 days after induction.
  
  
  CONCLUSIONS
  The findings are similar to human NAION. Therefore, RB-laser induction is well suited to establish the presence of rNAION.
authors.affiliation: Department of Ophthalmology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki, Miyazaki 889-1692, Japan. 06121028@fc.miyazaki-u.ac.jp
authors.forename: Hideki
authors.initials: H
authors.lastname: Chuman
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Maekubo
authors.forename: Takako
authors.initials: T
authors.lastname: Osako
authors.forename: Yu
authors.initials: Y
authors.lastname: Kodama
authors.forename: Michitaka
authors.initials: M
authors.lastname: Ishiai
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Nao-I
mesh_terms: D000818:Animals; D003623:Dark Adaptation; D004195:Disease Models, Animal; D004594:Electrophysiology; D004596:Electroretinography; D005074:Evoked Potentials, Visual / Q000502:physiology; D005451:Fluorescein Angiography; D013700:Giant Cell Arteritis / Q000503:physiopathology; D008297:Male; D009412:Nerve Fibers / Q000473:pathology; D009898:Optic Disk / Q000098:blood supply / Q000473:pathology; D018917:Optic Neuropathy, Ischemic / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012165:Retinal Ganglion Cells / Q000473:pathology