Posters

Changes of ocular higher order aberration and visual quality in keratoconus eyes following rigid gas-permeable contact lens use

Poster Details

First Author: S.Vasavada INDIA

Co Author(s):    V. Vasavada   V. Vasavada   S. Srivastava   R. Chauhan           

Abstract Details

Purpose:

To compare the corneal aberrations and visual quality metrics in keratoconic eyes with and without specialized rigid gas-permeable(RGP)contact lens

Setting:

Iladevi Cataract & IOL Research Centre, Raghudeep Eye Hospital, Ahmedabad, India

Methods:

Prospective, interventional case series. 30 eyes(22 patients) with keratoconus were fitted with specialized RGP contact lenses(Rose K2 or semi-scleral). Dynamic & Static fitting assessments were performed and anterior segment OCT done over the lenses for vault measurement.All eyes were subject to wavefront aberrometry(i-Trace,Tracey Technology,USA).Zernike's polynomial was used to describe the wavefront measurements.Root mean square(RMS) values of the total HOAs,spherical aberrations,coma and trefoil were obtained in the same eye with and without contact lenses. We used paired sample t-test and independent-samples t-test to analyze the data.Modulation transfer function(MTF) and Streihl�â�€�™s ratio were also measured with and without contact lenses.

Results:

There was a significant improvement in the Best-Corrected Visual acuity from pre-CL (Mean 0.4 LogMAR) to post-CL fitting (Mean 0.18LogMAR). There was a significant reduction in Mean RMS values for total HOA from1.25�.56(SD) pre-CL to 0.23�.16, post-CL fitting. Similarly, there was a significant reduction in the mean RMS values of total spherical (-0.33 to 0.05), coma (0.81 to 0.17) and trefoil (0.45 to 0.11) aberrations, from pre to post RGP CL fitting (P<0.05).The MTF and Streihl�â�€�™s ratio also improved significantly after RGP contact lens.

Conclusions:

RGP Contact lenses could reduce higher-order aberrations and improve optical quality in keratoconus eyes. Thus, RGP Contact lenses are an excellent visual rehabilitation option for keratoconus.

Financial Disclosure:

NONE