title: Effects of multicurve RGP contact lens use on topographic changes in keratoconus.
abstract: OBJECTIVE
  To evaluate the effects of wearing rigid gas permeable (RGP) contact lenses on the topographic changes in keratoconus.
  
  
  METHODS
  Seventy-seven keratoconic eyes that wore multicurve RGP contact lenses and 30 keratoconic eyes that wore no contact lenses were retrospectively analyzed. The mean follow-ups were 22.6 and 20.5 months in the lens-wearing and control groups, respectively. Visual acuity, comfort, daily wearing time, and corneal staining were evaluated for both groups. The changes in topographic indices were compared between the lens-wearing and control groups.
  
  
  RESULTS
  Multicurve RGP lens corrected logarithm of the minimum angle of resolution visual acuity of the lens-wearing group significantly improved from -0.016+/-0.065 to -0.032+/-0.10 at follow-up (p=0.05). In the lens-wearing group with advanced keratoconus, the Sim Kmax, Sim Kmin, apical power, astigmatic index, and anterior elevation significantly decreased from 57.68+/-4.26 diopter (D), 50.50+/-2.32 D, 62.79+/-5.11 D, 7.20+/-0.55 D and 67.36+/-16.30 microm to 55.51+/-4.28 D, 49.62+/-3.26 D, 60.31+/-5.41 D, 5.90+/-0.51 D and 60.61+/-16.09 microm, respectively (paired t-test, p<0.05). The irregularity index of 3 mm did not significantly change. Meanwhile, in the control group, the apical power and irregularity index increased from 55.56+/-7.25 D and 3.06+/-1.68 D to 57.11+/-7.75 D and 3.25+/-1.71 D, respectively (paired t-test, p=0.008, p=0.01).
  
  
  CONCLUSIONS
  Properly fitted multicurve RGP contact lenses are not likely to contribute to the progression of keratoconus.
authors: Department of Ophthalmology, Haenam Genenral Hospital, Jeonnam, Korea.
authors: Joon Seo
authors: JS
authors: Hwang
authors: Jin Hak
authors: JH
authors: Lee
authors: Won Ryang
authors: WR
authors: Wee
authors: Mee Kum
authors: MK
authors: Kim
mesh_terms: D000328:Adult; D001251:Astigmatism / Q000209:etiology / Q000473:pathology / Q000628:therapy; D003261:Contact Lenses; D003315:Cornea / Q000473:pathology*; D019781:Corneal Topography; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007640:Keratoconus / Q000150:complications / Q000473:pathology / Q000628:therapy*; D008297:Male; D011379:Prognosis; D011474:Prosthesis Design; D012189:Retrospective Studies; D013997:Time Factors; D055815:Young Adult