Clinical and simulated impact of intraocular lens tilt and decentration based on real-world data and optical simulation

The aim of this study was to determine whether the optical degradation induced by clinically measured intraocular lens (IOL) tilt and decentration, quantified through individualized synthetic eye models, translates into measurable changes in subjective refraction or visual acuity (BCVA). We included 105 eyes implanted with monofocal aspheric IOL and measured their positioning using AS-OCT. These data were used to reconstruct each eye in optical simulation software and evaluate four scenarios: aligned, decentered, tilted, and combined decentration and tilt. For each case, we calculated wavefront aberrations, three objective refractions, and predicted visual acuity from the radial MTF. The average IOL tilt was 5.19 ± 1.28° and decentration was 0.25 ± 0.13 mm. Coma RMS increased from 0.00 μm in the aligned model to 0.26 ± 0.09 μm in the most altered scenario (p < 0.001), and VSX decreased from 0.80 ± 0.11 to 0.35 ± 0.17. Despite this optical degradation, BCVA remained unaffected, with a mean of 0.00 ± 0.05 LogMAR, and no significant correlation was found with tilt or decentration. The best agreement between simulated and clinical refraction was observed when both tilt and decentration were included. These results suggest that moderate IOL misalignment degrades optical quality without compromising visual acuity in monofocal IOLs, but further studies are needed for multifocal designs.