Effect of rigid gas permeable contact lens on wavefront aberration and contrast visual acuity in low to moderate myopia / 中华实验眼科杂志

ABSTRACT

Background Rigid gas permeable (RGP) contact lens,as a kind of new correction of refraction error,has been wildly used,but whether it will cause eye optical system of the change and influence on the visual acuity is unclear.Objective Present study was to evaluate and compare the visual quality of low to moderate myopia following wearing of RGP contact lens and spectacles.Methods Sixty-eight eyes of 35 subjects with low or mediate myopia were included in this study.Wave-front aberrations and visual acuities under the different contrasts (10％,30％,40％,52％,76％,92％) in the light or dark environment were examined before and 3 months after wearing of RGP corneal contact lens.These parameters were compared with those after wearing of spectacles with paired t test.Results The best corrected visual acuity (BCVA) was improved significantly from 0.94±0.10 to 1.26±0.03 3 months after wearing of RGP corneal contact lens (t=-9.266,P=0.000).After fitting of RGP corneal contact lens,the total higher order wave-front aberrations,the 3rd and 4th order aberrations were significantly declined in comparison with those of before fitting (totalt=4.683,P=0.000;RMS3t=4.656,P=0.000;RMS4t=3.929,P=0.000).However,no significant differences were detected in the 5th and 6th order aberrations between RGP corneal contact lens fitting and spectacles wearing (RMS5t=1.766,P=0.083 ;RMS6t=1.150,P=0.256).In both bright and dark environments,BCVA values were much better in the eyes with RGP corneal contact lens wearing than that in the eyes with spectacles wearing (all P＜0.05).The BCVA was always reduced with the decline of contrast level whether bright or dark backgrounds both in RGP corneal contact lens wearing eyes and spectacles wearing eyes.Conclusions Wearing of RGP corneal contact lens provides better visual quality for low to moderate myopia than the spectacles wearing.