Influence of decentration and tilt of Tecnis ZCB00 on visual acuity and higher order aberrations

To determine the influence of decentration and tilt of a pseudophakic aspheric intraocular lens (IOL) on visual acuity (VA) and higher-order aberrations (HOAs), and to analyze the agreement between pupil center/axis and iridocorneal angles center/axis when assessing IOL decentration and tilt.

A prospective interventional case series study including thirty-three patients undergoing Tecnis ZCB00 (Abbott Medical Optics) implantation. IOL decentration and tilt with respect to two reference systems (pupil and iridocorneal angles centers/axes), in cartesian (X,Y) and polar (radius/tilt, polar angle/azimuth) coordinates, were assessed with optical coherence tomography. VA and internal and ocular HOAs were evaluated. Multiple linear regression models and intraclass correlation coefficient (ICC) were computed.

IOL decentration only showed a significant effect on internal HOAs for [Formula: see text] (R² = 0.20, P = 0.04). IOL decentration with respect to the pupil center showed a significant effect on ocular [Formula: see text] (R² = 0.18, P = 0.05), [Formula: see text] (R² = 0.36, P = 0.001) and [Formula: see text] (R² = 0.24, P = 0.02); and with respect to the center of iridocorneal angles, on ocular [Formula: see text] (R² = 0.21, P = 0.03), [Formula: see text] (R² = 0.32, P = 0.003), primary coma (R² = 0.41, P < 0.001), and coma-like (R² = 0.40, P = 0.001). Poor agreement between both reference systems was found for IOL decentration measurements (ICC ≤ 0.41), except for the polar angle coordinate (ICC = 0.83). Tilt measurements showed good agreement (ICC ≥ 0.75).

Tecnis ZCB00 decentration and tilt values after uneventful implantation appear not to have influence on VA, and their effect on HOAs are not high enough to clinically affect quality of vision. Pupil and iridocorneal angles used as reference systems may be interchangeable for IOL tilt measurements, but not for decentration.