Korean J Ophthalmol.  2010 Aug;24(4):201-206. 10.3341/kjo.2010.24.4.201.

Effects of Multicurve RGP Contact Lens Use on Topographic Changes in Keratoconus

• Hwang JS
• Lee JH
• Wee WR
• Kim MK

• KMID: 949056
• DOI: http://doi.org/10.3341/kjo.2010.24.4.201

Abstract

PURPOSE
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.

Keyword

Contact lenses; Cornea; Corneal topography; Keratoconus

MeSH Terms

Adult
Astigmatism/etiology/pathology/therapy
*Contact Lenses
Cornea/*pathology
*Corneal Topography
Disease Progression
Female
Follow-Up Studies
Humans
Keratoconus/complications/pathology/*therapy
Male
Prognosis
Prosthesis Design
Retrospective Studies
Time Factors
Young Adult

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