title: Surface interactions on hydrogel extended wear contact lenses: microflora and microfauna.
abstract: The microbial flora and fauna of 25 high water content nonionic "soft" contact lenses worn by patients on an extended wear basis, 4 hand-cleaned patient-worn lenses, and 4 improperly maintained lenses were compared. Almost all the patient-worn lenses (24 of 25) were free of viable microorganisms, whereas all the hand-cleaned lenses (4 of 4) were contaminated with different microorganisms. This study showed that hand contact is a major source of microbial contamination of a lens and that usually the hand-transported microorganisms do not survive permanently on the lens in a healthy, normal eye. Improperly maintained lenses demonstrated pathogenic microbial associations. Proof of the eye's potent antimicrobial environment was demonstrated. Thus, microorganism-lens associations are largely due to lens handling and inappropriate maintenance regimens. Typically there are few microorganisms on an extended wear soft lens while it is being worn.
mesh_terms: D003262:Contact Lenses, Extended-Wear; D003263:Contact Lenses, Hydrophilic; D004866:Equipment Contamination; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D008855:Microscopy, Electron, Scanning; D011092:Polyethylene Glycols
chemical_list: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D011092:Polyethylene Glycols