title: Effect of lens care system on silicone hydrogel contact lens wettability.
abstract: OBJECTIVE
  The purpose was to compare the effect of the repeated usage of two care systems (one hydrogen peroxide cleaning and disinfecting system and one polyaminopropyl biguanide (PHMB) containing multi-purpose system) with silicone hydrogel contact lenses worn for three months on a daily wear modality. A specific aspect of interest was of the effect of the care systems on contact lens wettability.
  
  
  METHODS
  Seventy-four symptomatic contact lens wearers, habitually wearing either ACUVUE(®) OASYS(®) (n=37) or PureVision™ (n=37), constituted the study population. The study was a two-arm prospective, investigator-masked, bilateral study of three-month duration to evaluate the effects of CLEAR CARE(®) compared with renu(®) fresh™. The subjects were randomized to one of the two lens care systems. Contact lens wettability and surface cleanliness were assessed with the Tearscope and reported in terms of pre-lens non-invasive break-up time (PL-NIBUT) and visible deposits. Baseline assessments at enrollment were with the subjects' own contact lenses worn for at least 6h when using their habitual PHMB-preserved care system and at the dispensing visit with new contact lenses. At the follow-up visits, the contact lenses were worn for at least 6h, and were at least 11 days old for ACUVUE(®) OASYS(®) and 25 days old for PureVision™.
  
  
  RESULTS
  The results obtained showed that: (i) with CLEAR CARE(®), a significant improvement in contact lens wettability was recorded compared with the habitual care system at the three-month follow-up visit (mean median PL-NIBUT 5.8 vs. 4.0 s, p<0.001). Further, with this same lens care system a significant increase in wettability was observed at the three-month follow-up visit compared with dispensing (mean median PL-NIBUT 5.8 vs. 4.5s, p=0.022). (ii) Whereas no difference in contact lens wettability was observed at dispensing between the two lens care groups (mean PL-NIBUT: 4.5 vs. 4.2s, p=0.518), a significantly more stable pre-lens tear film was observed with CLEAR CARE(®) than with renu(®) fresh™ at both the two-month (mean PL-NIBUT: 4.6 vs. 3.7s, p=0.005) and three-month (mean PL-NIBUT: 5.8 vs. 4.2 s, p=0.028) visits. iii. With renu(®) fresh™, no significant differences were observed at the end of three months of use compared with either the habitual care system or the new contact lens solution (mean PL-NIBUT: 3M 4.2 vs. Disp 4.2 s (p=0.420) vs. enrolment habitual care solution 5.1s (p=0.734)). iv. With CLEAR CARE(®) significant increases in the incidence of surfaces free of both mucus (3 month 95%. vs. habitual solution 82% enrolment; p=0.005) and lipid (3 month 87% vs. habitual solution 72% enrolment; p=0.009) were observed.
  
  
  CONCLUSIONS
  Significantly better contact lens wettability and surface cleanliness were achieved for ACUVUE(®) OASYS(®) and PureVision™ with CLEAR CARE(®) than with renu(®) fresh™ at the end of three months of use.
authors.affiliation: OCULAR TECHNOLOGY GROUP-International, London, UK; School of Life and Health Science, Aston University, Birmingham, UK. Electronic address: mguillon@otg.co.uk.
authors.forename: Michel
authors.initials: M
authors.lastname: Guillon
authors.affiliation: School of Life and Health Science, Aston University, Birmingham, UK; Alcon Research, Ltd., Fort Worth, TX, USA.
authors.forename: Cécile
authors.initials: C
authors.lastname: Maissa
authors.affiliation: OCULAR TECHNOLOGY GROUP-International, London, UK.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Wong
authors.affiliation: OCULAR TECHNOLOGY GROUP-International, London, UK.
authors.forename: Trisha
authors.initials: T
authors.lastname: Patel
authors.affiliation: Alcon Research, Ltd., Fort Worth, TX, USA.
authors.forename: Renée
authors.initials: R
authors.lastname: Garofalo
mesh_terms: D000328:Adult; D000368:Aged; D001645:Biguanides / Q000494:pharmacology*; D018639:Contact Lens Solutions / Q000494:pharmacology*; D003263:Contact Lenses, Hydrophilic; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012826:Silicone Elastomers; D017155:Wettability / Q000187:drug effects*; D055815:Young Adult
chemical_list: D001645:Biguanides; D018639:Contact Lens Solutions; D012826:Silicone Elastomers; C064420:polyaminopropylbiguanide; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D006861:Hydrogen Peroxide
keywords: Care system; Contact lens; Silicone hydrogel; Wettability