Higher order aberrations induced by soft contact lenses in normal eyes with myopia

To evaluate and compare the wavefront characteristics of normal eyes with and without hydrogel soft contact lenses for correction of myopia.

Higher order aberrations (HOA) of 30 eyes of 15 soft contact lens users who had no ocular diseases other than myopia were quantified with a Nidek Marco three dimensional Wave wavefront analyzer. Zernike's polynomial was used to describe the wavefront measurements. Root mean square (RMS) values of the total HOAs, total coma, total trefoil and total spherical aberrations were obtained in the same eyes with and without soft contact lenses. We used paired sample t-test to analyze the data.

Mean RMS values for all higher order aberration components with and without soft contact lenses were: total HOA 0.364 +/- 0.129 microm without lenses and 0.456 +/- 0.175 microm with lenses (P = 0.01), total coma 0.203 +/- 0.095 microm without lenses and 0.220 +/- 0.133 microm with lenses (P = 0.51), total trefoil 0.193 +/- 0.074 microm without lenses and 0.254 +/- 0.153 microm with lenses (P = 0.06), total spherical aberration 0.126 +/- 0.121 microm without lenses and 0.148 +/- 0.095 microm with lenses (P = 0.36).

Wavefront analysis showed soft contact lenses for myopia induced a significant increase in total HOA. Though total coma, trefoil and spherical aberrations were also higher with contact lenses they were not statistically significant when individually evaluated and compared to values without contact lenses.