title: Hydrogel lens comfort in challenging environments and the effect of refitting with silicone hydrogel lenses.
abstract: OBJECTIVE
  The purpose of this analysis was to measure the proportion of soft contact lens wearers who wear lenses in challenging environments and to evaluate their resulting comfort in those conditions. A second objective was to determine whether refitting with silicone hydrogel lenses affects lens comfort among subjects who wear lenses in these environments.
  
  
  METHODS
  Baseline data were collected from 496 hydrogel soft lens wearers on the frequency of use of contact lenses and the associated comfort in 12 challenging environments. Subjects were then refit into second generation silicone hydrogel lenses: senofilcon A (n = 228), galyfilcon A (n = 132), or lotrafilcon B (n = 136). Comfort responses were compared for subjects who "always" or "frequently" used lenses in the queried environments after 2 weeks of silicone hydrogel daily lens wear.
  
  
  RESULTS
  More than 80% of subjects used habitual lenses "always" or "frequently" while reading, sitting in an air-conditioned or heated car, using a computer and while driving at night. Less than 40% used lenses "always" or "frequently" while riding in an airplane, at high altitudes, or while napping or sleeping. The least comfortable environments were in dusty, polluted or smoky environments (30% comfortable), and the most comfortable were while reading and using a computer. After 2 weeks use of senofilcon A and galyfilcon A lenses, comfort in all environments improved significantly (Wilcoxon signed rank) except for using a computer with galyfilcon A. After 2 weeks with lotrafilcon B lenses, there was improved comfort while using lenses in all environments except driving at night, using a computer and sitting in an air-conditioned or heated car (p < 0.04, Wilcoxon signed rank).
  
  
  CONCLUSIONS
  Daily wear contact lens wearers limit use of lenses during air travel or while napping. Use of daily wear silicone hydrogel lenses improved comfort significantly in most environments, allowing subjects to wear them in challenging environments.
authors: Visioncare Research Ltd., Farnham, Surrey, United Kingdom.
authors: Graeme
authors: G
authors: Young
authors: Colleen M
authors: CM
authors: Riley
authors: Robin L
authors: RL
authors: Chalmers
authors: Chris
authors: C
authors: Hunt
mesh_terms: D000203:Activities of Daily Living; D000293:Adolescent; D000328:Adult; D003262:Contact Lenses, Extended-Wear / Q000592:standards*; D004777:Environment; D004781:Environmental Exposure / Q000009:adverse effects; D005260:Female; D005500:Follow-Up Studies; D006184:Habits; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D008297:Male; D010549:Personal Satisfaction; D012826:Silicone Elastomers; D011795:Surveys and Questionnaires
chemical_list: D012826:Silicone Elastomers; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate