title: Morphological damage in rabbit retina caused by subretinal injection of indocyanine green.
abstract: OBJECTIVE
  To investigate the effects of subretinal indocyanine green (ICG) on retinal morphology in rabbit eyes.
  
  
  METHODS
  Retinal bleb detachments were produced by injections of ICG at dosages of 25 mg/ml, 5 mg/ml, and 0.5 mg/ml or with an injection of balanced salt solution (BSS) into the subretinal space of albino rabbit eyes. Morphological change was assessed by light and transmission electron microscopy from the viewpoint of dose and time. Some sections were also probed with the TUNEL technique to detect apoptotic cells.
  
  
  RESULTS
  At 14 days after subretinal injection of BSS and 0.5 mg/ml ICG, the structure of the retina was well preserved. However, injections of 5 mg/ml or 25 mg/ml caused thinning of the retina, especially loss of the outer retinal layer. In eyes injected with 5 mg/ml ICG, the photoreceptors began disappearing within 3 days after the injection and over time showed the development of retinal atrophy. TUNEL-positive cells appeared abundantly in the photoreceptor layers 1 and 3 days after the injection of 5 mg/ml ICG. Transmission electron microscopy confirmed apoptosis in the photoreceptors.
  
  
  CONCLUSIONS
  These data indicate that subretinal ICG induces apparent morphological damage of the retina in a dose-dependent manner.
authors.affiliation: Department of Ophthalmology and Visual Science, Kumamoto University Graduate School of Medical Sciences, Honjo 1-1-1, 860-8556, Kumamoto , Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kawaji
authors.affiliation: Department of Ophthalmology and Visual Science, Kumamoto University Graduate School of Medical Sciences, Honjo 1-1-1, 860-8556, Kumamoto , Japan. ahirata@kumamoto-u.ac.jp.
authors.forename: Akira
authors.initials: A
authors.lastname: Hirata
authors.affiliation: Department of Ophthalmology and Visual Science, Kumamoto University Graduate School of Medical Sciences, Honjo 1-1-1, 860-8556, Kumamoto , Japan.
authors.forename: Yasuya
authors.initials: Y
authors.lastname: Inomata
authors.affiliation: Department of Ophthalmology and Visual Science, Kumamoto University Graduate School of Medical Sciences, Honjo 1-1-1, 860-8556, Kumamoto , Japan.
authors.forename: Takahisa
authors.initials: T
authors.lastname: Koga
authors.affiliation: Department of Ophthalmology and Visual Science, Kumamoto University Graduate School of Medical Sciences, Honjo 1-1-1, 860-8556, Kumamoto , Japan.
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Tanihara
mesh_terms: D000818:Animals; D017209:Apoptosis; D001284:Atrophy; D004396:Coloring Agents / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D020287:In Situ Nick-End Labeling; D007208:Indocyanine Green / Q000633:toxicity*; D007267:Injections; D011817:Rabbits; D012160:Retina / Q000187:drug effects* / Q000648:ultrastructure; D012164:Retinal Diseases / Q000139:chemically induced* / Q000473:pathology
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green