title: In vitro bacterial adherence to hydrogel and poly(methyl methacrylate) intraocular lenses.
abstract: OBJECTIVE
  To compare the in vitro adherence of Staphylococcus epidermidis to poly-(hydroxyethyl methacrylate) (polyHEMA) or hydrogel intraocular lenses (IOLs) and poly(methyl methacrylate) (PMMA) IOLs.
  
  
  METHODS
  Lions Eye Institute, Perth, Western Australia.
  
  
  METHODS
  One-piece hydrogel lenses and one-piece PMMA lenses were suspended for 60 minutes in standardized suspensions of a well-characterized strain of S. epidermidis and then sonicated in a known quantity of balanced salt solution to remove the adherent bacteria. Quantitative cultures of the sonicates were performed and the results analyzed statistically.
  
  
  RESULTS
  The mean bacterial adherence of S. epidermidis to the PMMA IOLs (58,400 CFU) was more than 20 times greater than that to the hydrogel IOLs (1953 CFU). The difference was statistically significant (P < .001).
  
  
  CONCLUSIONS
  Adherence of S. epidermidis to hydrogel IOLs is significantly lower than to PMMA IOLs. This suggests that the risk of postoperative endophthalmitis after cataract extraction and IOL implantation may be lower with the use of hydrogel IOLs.
authors.affiliation: Department of Ophthalmology, University of Western Australia School of Medicine, Perth, Australia.
authors.forename: E W
authors.initials: EW
authors.lastname: Ng
authors.forename: G D
authors.initials: GD
authors.lastname: Barrett
authors.forename: R
authors.initials: R
authors.lastname: Bowman
mesh_terms: D001422:Bacterial Adhesion; D015169:Colony Count, Microbial; D003627:Data Interpretation, Statistical; D066298:In Vitro Techniques; D007910:Lenses, Intraocular / Q000382:microbiology; D008689:Methacrylates / Q000378:metabolism*; D008768:Methylmethacrylates / Q000378:metabolism*; D013212:Staphylococcus epidermidis / Q000378:metabolism*
chemical_list: D008689:Methacrylates; D008768:Methylmethacrylates; C005044:hydroxyethyl methacrylate