Visual Acuity Loss in Keratoconus

Abstract

Abstract: : Purpose: The Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study is an observational study of more than 1200 keratoconus patients. We sought to determine the percentage of eyes that lost 10 letters or more of visual acuity (VA) over 4 years of follow-up and to examine the association of baseline factors with this acuity loss. Methods: We identified eyes that lost 10 letters or more of high contrast habitual visual acuity or low contrast visual habitual acuity after 4 years of follow-up. We report univariate analyses (percentages, means, standard deviations) of baseline factors for eyes that did and did not lose 10 letters or more of habitual visual acuity. Results: Thirteen percent (269 of 2064 eyes) lost 10 letters or more in high contrast habitual visual acuity, and 16.7% (344 of 2,062 eyes) lost 10 letters or more in low contrast habitual visual acuity. Conclusions: Clinically significant loss of visual acuity (10 letters or more) was observed in 13-17% of eyes in 4 years. In univariate analyses, baseline factors that were associated with this loss of acuity included female gender, corneal scarring, contact lens wear, steeper corneal curvature, and worse initial acuity. Baseline values for eyes that lost 10 letters or more of visual acuity compared to eyes that did not  

Keywords: keratoconus • cornea: clinical science • contact lens