Abstract
Abstract: :
Purpose: To investigate the change of high order aberration(HOA) in keratoconic eyes and myopic eyes with rigid gas permeable(RGP) contact lenses wearing. Methods: In 18 keratoconic eyes which average keratometric index was 44.27±2.65diopter and 41 myopic eyes, the root mean square(RMS) values of high order aberrations(HOAs) were obtained using wave scan(Visx WS1, Santa Clara, USA) before and after wearing of RGP. Results: Total HOA, coma, and trefoil aberration RMS values decreased by 0.029, 0.042, 0.056, respectively, and spherical aberration increased by 0.139 in keratoconus with RGP wearing. However, these changes were not statistically significant. Total HOA, trefoil, and spherical aberration RMS values were decreased by 0.018, 0.065, 0.147, respectively, and coma aberration was increased by 0.327 in myopic eyes. Only the trefoil aberration was significantly changed(p=0.001). The change of spherical aberration was significantly different between the two groups(p=.016). In myopic eyes with total HOA equal to or greater than 0.30 before the wearing, total HOA and trefoil aberration significantly decreased by 0.137 and 0.127(p=0.000) after RGP wearing. On the contrary, total HOA and coma aberration significantly increased with RGP wearing by 0.085 and 0.101(p=0.000) in eyes with total HOA lower than 0.30 before the wearing. Conclusions: Wearing of the RGP did not influence the HOAs in keratoconic eyes. However, RGP wearing seemed to reduce total HOA by decreasing trefoil in eyes with primarily high HOA, and RGP wearing seemed to augment total HOA by increasing coma in eyes with originally low HOA.
Keywords: contact lens • keratoconus • myopia