title: Toxicity profiles of subretinal indocyanine green, Brilliant Blue G, and triamcinolone acetonide: a comparative study.
abstract: BACKGROUND
  This study introduces a novel porcine model to examine the histopathological and electrophysiological consequences of retinotoxicity exerted by dyes commonly used for internal limiting membrane (ILM) staining.
  
  
  METHODS
  Indocyanine green (ICG) 0.5 mg/ml, Brilliant Blue G (BBG) 0.25 mg/ml and triamcinolone acetonide (TA) 13 mg/ml was injected subretinally in 12 vitrectomized pig eyes. At 6 weeks, retinas were examined by multifocal electroretinography (mfERG), ophthalmoscopy, fluorescein angiograpy, histopathology, and apoptosis assay.
  
  
  RESULTS
  mfERG responses were significantly lower in ICG-injected eyes than in healthy fellow eyes (p = 0.039). The ratio between injected eyes and healthy fellow eyes was lower in the ICG group than in the BBG (p = 0.009) and TA group (p = 0.025). No difference between BBG and TA existed. All retinas were reattached, and fluorescein angiographies showed a window defect corresponding to the injected areas but no blood-retina barrier break-down. Histopathology confirmed damage to the outer retina after ICG, but not after BBG and TA. No apoptosis was found at 6 weeks.
  
  
  CONCLUSIONS
  Subretinal ICG induces histological and functional damage to the retina, suggesting that ICG should be used with caution in macular hole surgery, where subretinal migration can occur. In contrast, BBG and TA appear safe after subretinal injection.
authors.affiliation: Department of Ophthalmology, Glostrup Hospital, University of Copenhagen, Nordre Ringvej 57, 2600, Glostrup, Denmark. rasmusejstrup@hotmail.com
authors.forename: Rasmus
authors.initials: R
authors.lastname: Ejstrup
authors.forename: M
authors.initials: M
authors.lastname: la Cour
authors.forename: S
authors.initials: S
authors.lastname: Heegaard
authors.forename: J F
authors.initials: JF
authors.lastname: Kiilgaard
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001813:Blood-Retinal Barrier / Q000187:drug effects; D004396:Coloring Agents / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004596:Electroretinography / Q000187:drug effects; D005260:Female; D005451:Fluorescein Angiography; D005938:Glucocorticoids / Q000633:toxicity*; D007208:Indocyanine Green / Q000633:toxicity*; D023421:Models, Animal; D009887:Ophthalmoscopy; D012160:Retina / Q000187:drug effects* / Q000473:pathology; D012394:Rosaniline Dyes / Q000633:toxicity*; D034421:Sus scrofa; D014222:Triamcinolone Acetonide / Q000633:toxicity*; D014821:Vitrectomy
chemical_list: D004396:Coloring Agents; D005938:Glucocorticoids; D012394:Rosaniline Dyes; D014222:Triamcinolone Acetonide; D007208:Indocyanine Green; C004692:coomassie Brilliant Blue