title: Comfort and adaptation to silicone hydrogel lenses for daily wear.
abstract: OBJECTIVE
  To investigate initial comfort and adaptation of currently successful low oxygen transmissibility soft lens wearers refitted with silicone hydrogel (SH) lenses for daily wear.
  
  
  METHODS
  Fifty-five subjects were enrolled in a subject-masked 5-month clinical trial in which they wore 5 SH lenses in a randomized, crossover design. Comfort, burning, and dryness were rated on scales of 0 to 100 immediately on insertion and the time for lens settling was recorded. Symptoms were then rated at various times, using BlackBerry wireless communication devices (Research in Motion, Waterloo, Canada), during the day for 2 cycles of 2 weeks wear for each lens type.
  
  
  RESULTS
  Comfort immediately on insertion varied between lens types (P=0.002). All lens types were reported by the subjects to have settled within 30 to 45 sec of insertion (P=0.14) and "settled" comfort was greater than comfort immediately on insertion (P<0.001). Comfort within the first hour of wear also varied between lens types (P=0.02). Comfort during the day decreased significantly for all lenses (P=0.001), but there was no difference between lenses (P=0.19) and no effect of lens age (P=0.15). The wearing times were greater with the SH lenses than the habitual lenses worn before study commencement (P=0.001). Overall performance of the lenses after 4 weeks was high, with no difference between lenses (P=0.45).
  
  
  CONCLUSIONS
  Initial comfort and adaptation to all SH lenses were good and no differences in the overall ratings were found between the 5 SH lenses investigated. Decreased comfort was noted later in the day with all lens types, but longer wearing times were reported with the SH lenses than previous hydroxyethyl methacrylate-based lenses.
authors.affiliation: Centre for Contact Lens Research, School of Optometry, University of Waterloo, Waterloo, Ontario, Canada. kdumble@sciborg.uwaterloo.ca
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Dumbleton
authors.forename: Craig A
authors.initials: CA
authors.lastname: Woods
authors.forename: Lyndon W
authors.initials: LW
authors.lastname: Jones
authors.forename: Desmond
authors.initials: D
authors.lastname: Fonn
mesh_terms: D000221:Adaptation, Ocular / Q000502:physiology*; D000293:Adolescent; D000328:Adult; D003263:Contact Lenses, Hydrophilic; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011446:Prospective Studies; D011474:Prosthesis Design; D017755:Prosthesis Fitting; D012030:Refractive Errors / Q000628:therapy; D012828:Silicones; D016037:Single-Blind Method; D055815:Young Adult
chemical_list: D012828:Silicones; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate