title: Effect of 30-day continuous wear of silicone hydrogel contact lenses on corneal thickness.
abstract: OBJECTIVE
  To investigate the effect of 30-day continuous-wear contact lenses (Focus Night & Day) on corneal thickness and physiology.
  
  
  METHODS
  Twenty-six myopic eyes with no history of contact lens wear were fitted with silicone hydrogel contact lenses. Complete ophthalmologic examinations, corneal topography, and corneal thickness measurements at the center and eight peripheral areas were performed before fitting and at each visit, namely on day 1, day 10, and 1 month. Mean corneal thicknesses were statistically compared by using one-way repeated-measures analysis of variance.
  
  
  RESULTS
  All patients maintained their 20/20 vision with correction. Limbal vascularization was noted in one patient at the end of the study. No patient had subjective complaints. In another patient, a punctate corneal epithelial defect was noted on the 15th day, but it healed when the contact lens was removed for a day. The mean corneal thicknesses in different regions were significantly increased by approximately 14 to 38 microm compared with baseline measurements. There were no significant differences between the corneal topography taken on the first day and the one taken at the end of the first month.
  
  
  CONCLUSIONS
  All patients maintained their visual acuity. Apart from the limbal vascularization and punctate epithelial corneal defects, which resolved when the contact lens was removed for 1 day, no serious complications were noted. Despite the high oxygen permeability of the monthly Night & Day contact lenses, the mean central and peripheral corneal thicknesses increased. These increases indicate that these lenses may have an effect on corneal metabolism.
authors.affiliation: Department of Ophthalmology, Istanbul Faculty of Medicine, Istanbul University, Capa Istanbul 34390, Turkey. byeniad@yahoo.com
authors.forename: Bariş
authors.initials: B
authors.lastname: Yeniad
authors.forename: Yakubi Seidu
authors.initials: YS
authors.lastname: Adam
authors.forename: Lale Közer
authors.initials: LK
authors.lastname: Bilgin
authors.forename: Nilüfer
authors.initials: N
authors.lastname: Gözüm
mesh_terms: D000328:Adult; D003262:Contact Lenses, Extended-Wear; D003315:Cornea / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D009216:Myopia / Q000378:metabolism / Q000628:therapy*; D010100:Oxygen / Q000378:metabolism; D010539:Permeability; D014792:Visual Acuity
chemical_list: D010100:Oxygen