Posters

The correlation between visual acuity and contrast sensitivity and refractive, topographic, pachymetric and aberrometric data in eyes with keratoconus

Poster Details

First Author: C.Arce BRAZIL

Co Author(s):    I. Hepsen   N. Bilen           

Abstract Details

Purpose:

To analyze the relationship among near and far visual acuities and contrast sensitivity with refractive, topographic, pachymetric, and aberrometric indicators in eyes with keratoconus

Setting:

Department of Ophthalmology, School of Medicine, Fatih University, Ankara, Turkey

Methods:

Best-corrected distance (CDVA) and near (CNVA) visual acuities, and letter-contrast sensitivity (LCS) were correlated with refraction, corneal topography, pachymetry, and total corneal wavefront (WF) data prospectively in 123 eyes with keratoconus. The indices assessed with the Galilei (Ziemer Ophthalmic Systems AG, Port, Switzerland) were SimK steep, SimK flat, posterior steeper K (postK steep), maximum elevation value in best-fit sphere maps (BFS max), squared eccentricity (Є2), Kranemann-Arce index (KAI), thickness progression index (TPI), the amount of pachymetric decentralization (APD), the regular Galilei keratoconus indices (KPI, KProb, I-S, SRI, IAI and others), RMS, spherical aberration (SA), and coma

Results:

The mean CDVA and CNVA were 0.23±0.25, and 0.4±0.22, respectively. The most affected visual function was the LCS: mean ±SD of 9.8±3.09. The cylindrical refraction correlated well with LCS (r=0.602,p<0.001) and CNVA (r=0.550, p<0.001). From topographic indices, SRI correlated with LCS (r=-0.791), and CNVA (r=-0.770), and IAI with LCS (r=-0.761), (p<0.001 for all). RMS was 3.9±1.92 µm, spherical aberration (SA) was -0.3±0.61 µm, vertical and horizontal coma was -1.9±1.36 and 0.6±0.50 µm. All WF data, the KAI, the BFS max and the Є2 correlated significantly with the three parameters of quality of vision (p≤0.001 for all)

Conclusions:

In this study, LCS was the most affected visual function. CDVA) and near (CNVA, and LCS correlated well with SRI and IAI, which are well-known topographic indices for keratoconus, as well as with WF data. New indices such as KAI, BFS max and Є2 seemed also useful for estimating the quality of vision in eyes with keratoconus FINANCIAL INTEREST: One of more of the authors... receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented, One of more of the authors... travel has been funded, fully or partially, by a company producing, developing or supplying the product or procedure presented