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Bitoric gas-permeable contact lens application in pellucid marginal corneal degeneration
Charles E Dominguez1, Arti Shah, Barry A Weissman
1Jules Stein Eye Institute, Department of Ophthalmology, David Geffen School of Medicine at UCLA, University of California, Los Angeles, CA 90024, USA.
Purpose:
To evaluate the authors' experience fitting patients with pellucid marginal corneal degeneration (PMCD) with bitoric gas-permeable contact lenses.
Methods:
The records of 11 patients with a confirmed diagnosis of PMCD were retrospectively reviewed. The numbers of diagnostic contact lenses at the first visit, office visits, and lenses ordered to complete the fitting; uncorrected, spectacle-corrected, and contact lens-corrected Snellen visual acuities; contact lens success or failure; and complications encountered were all assessed. These data were compared to historic data for patients with other corneal irregularities (keratoconus, penetrating keratoplasty, and refractive surgery).
Results:
The mean number of diagnostic contact lenses used at the first visit was 1.09 +/- 0.302, and the number of lenses ordered to complete the fitting was 1.82 +/- 1.33. The number of visits during 4 months was 6.18 +/- 2.14. Uncorrected visual acuity (logMAR) was 0.957 +/- 0.398 (20/181 in Snellen); the best-corrected spectacle visual acuity (logMAR) was 0.231 +/- 0.309 (20/34 in Snellen); and the best contact lens-corrected visual acuity (logMAR) was 0.0424 +/- 0.06275 (20/22 in Snellen). Corrected vision in eyes with PMCD improved approximately two lines with bitoric gas-permeable contact lenses compared to that achieved with spectacles. Ten (91) of the patients met the criteria of contact lens success during the 4-month follow-up period.
Conclusions:
Bitoric gas-permeable contact lenses achieved a comfortable and visually successful fit in most eyes with PMCD. Patients with PMCD used the fewest contact lenses and had the fewest lens exchanges, but required more office visits than other groups of patients with various corneal irregularities.
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