title: Do fenestrations affect the performance of orthokeratology lenses?
abstract: OBJECTIVE
  To investigate the effect of lens fenestrations on the performance of orthokeratology lenses.
  
  
  METHODS
  Twenty-two subjects (aged 11 to 31 years) were fitted with identical reverse geometry orthokeratology lenses in the two eyes. One eye was randomly designated to wear a lens with three 0.20 mm fenestrations at 120° intervals placed at the junction of the reverse and alignment curves. The lens for the other eye was not fenestrated. Subjects were reviewed at 1 week, 1 month, 3 months, 6 months, and 1 year after fitting. Data were collected on refraction, visual performance, incidences and severity of corneal staining, lens binding, and corneal pigmented arc.
  
  
  RESULTS
  Fifteen subjects achieved full correction in OU. There were no statistically significant differences in refractive and corneal changes, visual performance, incidences and severity of corneal staining and corneal pigmented arc formation between the two eyes. The incidence of lens binding was consistently higher in eyes wearing non-fenestrated lenses but was not statistically significant. Severity of lens binding, however, was statistically significant at the 1-, 3-, 6- and 12-month visits, with the non-fenestrated lenses causing more severe binding.
  
  
  CONCLUSIONS
  The addition of fenestrations to orthokeratology lenses has no effect on the efficacy of the treatment or outcomes in low to moderate myopic subjects. However, the severity of lens binding is reduced. Fenestrating reverse geometry lenses may be of assistance in cases where lens binding is a problem.
authors.affiliation: School of Optometry, The Hong Kong Polytechnic University, Hong Kong SAR, China.
authors.forename: Pauline
authors.initials: P
authors.lastname: Cho
authors.forename: Ben
authors.initials: B
authors.lastname: Chan
authors.forename: Sin Wan
authors.initials: SW
authors.lastname: Cheung
authors.forename: John
authors.initials: J
authors.lastname: Mountford
mesh_terms: D000293:Adolescent; D000328:Adult; D001251:Astigmatism / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D002648:Child; D003261:Contact Lenses; D003315:Cornea / Q000473:pathology*; D019781:Corneal Topography; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009216:Myopia / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D054158:Orthokeratologic Procedures / Q000379:methods*; D011446:Prospective Studies; D012029:Refraction, Ocular; D013997:Time Factors; D055815:Young Adult