J Korean Ophthalmol Soc.  2015 Jul;56(7):1006-1011. 10.3341/jkos.2015.56.7.1006.

Long-Term Effect and Safety of Contact Lenses for Keratoconus

• Lee JH
• Park YM
• Park YK
• Lee JS
• Lee JE

• KMID: 2148799
• DOI: http://doi.org/10.3341/jkos.2015.56.7.1006

Abstract

PURPOSE
To evaluate the long-term clinical effect and safety of YK-KC lens(R) (LucidKorea Ltd., Seoul, Korea) for keratoconus.
METHODS
In this study we investigated 152 keratoconic eyes fitted with YK-KC lens(R) and followed up for at least 5 years. We assessed retrospectively self-reported patient comfort, best corrected visual acuity, corneal topographic indices before and after contact lens fitting and complications during contact lens wearing.
RESULTS
The study included 57 male and 40 female patients with a mean age of 28.6 +/- 8.5 years. The mean follow-up was 8.0 +/- 2.9 years. Regarding lens comfort, 126 eyes (82.9%) showed self-reported comfort for YK-KC lenses(R). The mean best corrected visual acuity (log MAR) improved from 0.49 +/- 0.42 before lens fitting to 0.19 +/- 0.27 after lens wearing, which was statistically significant (p < 0.001). Based on the keratometric values, after contact lens fitting both Simulated keratometry (Sim K) max and Sim K min tended to be steeper, but these differences were not statistically significant (p = 0.66 and 0.11, respectively). There were no statistically significant differences between the values before and after fitting with respect to the astigmatic powers (p = 0.22). Complications observed included punctate or coalesced epithelial corneal staining in 24 eyes (16%), however, persistent full-thickness epithelial defect was not observed.
CONCLUSIONS
The YK-KC lens(R) in patients with keratoconus can provide excellent visual improvement and comfort without any significant influence on the progression of keratoconus or corneal complications during a long-term follow-up period.

Keyword

Contact lens; Keratoconus; YK-KC lens(R)

MeSH Terms

Contact Lenses*
Female
Follow-Up Studies
Humans
Keratoconus*
Male
Retrospective Studies
Seoul
Visual Acuity

Figure

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  Figure 1. Distribution of self-reported assessment of contact lens comfort.

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  Figure 2. Change in best-corrected visual activity (BCVA) be-tween spectacles and YK-KC lenses®. Points lying above the solid 45° line correspond to eyes with improved vision with YK-KC lenses®.

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  Figure 3. Distribution of visual acuity when wearing YK-KC lens®, plotted against the base curve radius of the lens. Better visual acuity was achieved when contact lenses with flatter base curve radii were fitted.

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  Figure 4. Correlations between topographic indices and contact lens base curve radius (BCR). 'r' means Pearson's correlation co-efficient between Sim K min and BCR (A), between average of Sim K and BCR (B), between Sim K max and BCR (C), and a rela-tionship is considered to be statistically significant if p < 0.05. Sim K = simulated keratometry; min = minimum.

Reference

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