Correlations between high-order wavefront aberrations and intraocular lens decentration or tilt

Abstract

Objective To investigate the influence of intraocular lens (IOL) decentration and tilt on high-order aberrations in pseudophakic eyes. Methods Sixty-six patients (84 eyes) with senile cataract were scheduled to have phacoemulsification and IOL implantation. Foldable IOL were implanted, which included Acrysof SA60AT (Alcon), Sensar AR40e (AMO), XLSTABI (IOLTECH)and QUATTRO SE (Corneal). The patients were examined 3 months after surgery. The decentration and tilt of the IOL were quantitated using Scheimpflug videophotography system (Pentacam, Oculus)and image-analyzing approaches. The high-order aberrations were measured using a Hartmann-Shack aberrometer (WASCA Analyzer, Zeiss) over a 3 mm or 5 mm pupil diameter. The correlations between high-order aberrations and IOL decentration or tilt were tested using Pearson's correlation coefficient. Moreover, the relationship between IOL decentration, tilt and high-order aberrations were assessed with stepwise multiple linear regression model. The correlations between Snellen visual acuity and IOL decentration or tilt were tested using Spearman rank correlation coefficient. Results For a 3 mm aperture diameter, the correlations between IOL tilt and total high-order aberrations (r=0.3488,P=0.0022) or coma-like aberrations (r=0.3880, P=0.0006) were positive, while the correlations between IOL tilt and spherical-like aberrations (r=0.0800, P=0.4951), secondary coma-like aberrations (r=0.2045, P=0.0784) or secondary spherical-like aberrations (r=0.1110, P=0.3431) were not significant.For a 5 mm aperture diameter, the correlations between IOL tilt and total high-order aberrations (r=0.2861, P=0.0128), coma-like aberrations (r=0.3298, P=0.0039) or secondary coma-like aberrations (r=0.2704, P=0.0190) were positive, while the correlations between IOL tilt and spherical-like aberrations (r=0.1482, P=0.2045) or secondary spherical-like aberrations (r=0.1460, P=0.2114) were not significant. For a 3 mm or 5 mm aperture diameter, the correlations between IOL decentration and total high-order aberrations or each class of aberrations were not significant (P＞0.05). The best corrected visual acuity had no significant correlation with IOL decentration (r=0.0266, P=0.8208) but a negative correlation with IOL tilt (r=-0.3272, P=0.0042). Conclusion IOL tilt affects the total high-order aberrations and coma-like aberrations in pseudophakic eyes, thereby decreasing the visual acuity of these patients. Key words: Lenses,intraocular; Tilt; Decentration; Wavefront aberration; Visual acuity