title: Rigid gas-permeable contact lens related life quality in keratoconic patients with different grades of severity.
abstract: OBJECTIVE
  The aim was to compare the impact of rigid gas-permeable (RGP) contact lenses on vision-related quality of life (VR-QOL) in keratoconic patients with different grades of severity.
  
  
  METHODS
  This comparative study was conducted from December 2012 to September 2013 on 46 patients with bilateral keratoconus. Patients were divided into three groups according to the average of the steep keratometry (K) readings in the two eyes of each patient. Main outcome measures included binocular visual acuity (VA), lens wearing time, the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25), foreign body (FB) sensation, comfort and overall satisfaction.
  
  
  RESULTS
  Patients with severe keratoconus showed significantly reduced wearing time compared with the other two groups (4.8 ± 2.5 hours per day). Regarding the subjective criteria, there was no significant difference on NEI-VFQ-25 scores, foreign body sensation, comfort and overall satisfaction between mild and moderate keratoconus groups but scores in the group with severe keratoconus were significantly lower than the other two groups. Binocular VA strongly correlated with NEI-VFQ-25 scores; however, NEI-VFQ-25 scores had no significant correlations with different disease severities.
  
  
  CONCLUSIONS
  Appropriate correction with RGP lenses contributes to good VR-QOL for keratoconic patients; however, as the disease progresses to a steep keratometric value of more than 52 dioptres (6.50 mm), RGP lenses did not guarantee a relatively good VR-QOL. Other lens options with new designs might bring better life quality for these patients with severe keratoconus.
authors.affiliation: Department of Optometry, West China School of Medicine, Sichuan University, Chengdu, Sichuan Province, China. b.q15651@hotmail.com.
authors.forename: Ye
authors.initials: Y
authors.lastname: Wu
authors.forename: Qi
authors.initials: Q
authors.lastname: Tan
authors.forename: Wenqiu
authors.initials: W
authors.lastname: Zhang
authors.forename: Jianglan
authors.initials: J
authors.lastname: Wang
authors.forename: Bi
authors.initials: B
authors.lastname: Yang
authors.forename: Wei
authors.initials: W
authors.lastname: Ma
authors.forename: Xue
authors.initials: X
authors.lastname: Wang
authors.forename: Longqian
authors.initials: L
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D000328:Adult; D003261:Contact Lenses; D003315:Cornea / Q000473:pathology*; D019781:Corneal Topography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000175:diagnosis / Q000523:psychology / Q000628:therapy*; D008297:Male; D017060:Patient Satisfaction; D011446:Prospective Studies; D017755:Prosthesis Fitting; D011788:Quality of Life; D012720:Severity of Illness Index; D055815:Young Adult
keywords: contact lenses; keratoconus; rigid gas-permeable; vision-related quality of life