title: Retinal Toxicity of Intravitreal Polyethylene Glycol 400.
abstract: OBJECTIVE
  Polyethylene glycol (PEG)-400 is a clear, colorless viscous liquid that readily dissolves many hydrophobic drugs. It is a widely used commercial solvent and vehicle for many pharmaceutical and cosmetic products. The purpose of this study is to investigate the intravitreal safety of PEG-400 to determine its suitability as a potential vehicle for intraocular drug delivery.
  
  
  METHODS
  Six healthy, male, Dutch Belted rabbits, weighing between 2.0 and 3.0 kg, were used for this experiment. The left eye of each animal received a single 0.1 mL intravitreal injection of PEG-400. Complete eye exams and dark- and light-adapted electroretinograms (ERG) were obtained at baseline and at 1 and 4 weeks after injection. After the 4-week ERG was completed, animals were euthanized, eyes were enucleated, and histology and transmission electron microscopy (TEM) were performed.
  
  
  RESULTS
  Ophthalmic examinations demonstrated diffuse signs of retinal degeneration and cataract formation in all 6 eyes injected with PEG-400, which was apparent at 1 week, but more evident by 4 weeks. Photopic and scotopic ERG studies demonstrated significant reduction in amplitudes at 1 and 4 weeks after injection compared to baseline. Histopathological and TEM analysis of eyes demonstrated both inner and outer retinal atrophy.
  
  
  CONCLUSIONS
  Intravitreal injection of PEG-400 resulted in severe ocular toxicity.
authors.affiliation: Vanderbilt Eye Institute, Vanderbilt University Medical Center , Nashville, Tennessee.
authors.forename: Shriji
authors.initials: S
authors.lastname: Patel
authors.affiliation: Vanderbilt Eye Institute, Vanderbilt University Medical Center , Nashville, Tennessee.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Barnett
authors.affiliation: Vanderbilt Eye Institute, Vanderbilt University Medical Center , Nashville, Tennessee.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Kim
mesh_terms: D000818:Animals; D004596:Electroretinography; D058449:Intravitreal Injections; D008297:Male; D011092:Polyethylene Glycols / Q000008:administration & dosage* / Q000633:toxicity*; D011817:Rabbits; D012164:Retinal Diseases / Q000188:drug therapy*; D014822:Vitreous Body / Q000187:drug effects / Q000473:pathology*
chemical_list: D011092:Polyethylene Glycols; C000595213:polyethylene glycol 400