[Investigation of the theoretical image quality of aspheric intraocular lenses by decentration. Hoya AF-1 iMics1 und Zeiss ASPHINA(TM) (Invent ZO)].

BACKGROUND

The image quality of aberration correcting aspherical intraocular lenses (IOLs) depends on the centration in the eye. Aberration correcting IOLs of the second generation are claimed to be more robust to decentration. In this study the image quality of such IOLs was analyzed with decentration values of up to 1 mm.

MATERIALS AND METHODS

In this study two aberration correction IOLs of the second generation were compared in a model eye. The IOLs were decentered for two pupil diameters (3.0 and 4.5 mm) in a range of ± 1 mm relative to the line of sight in 50 µm steps and the modulation transfer function was calculated. The results were compared for different spatial frequencies and visual acuities.

RESULTS

The analyzed IOLs are superior to the spherical IOL in a decentration range from -0.45 mm to 0.60 mm (30 CPD, cycles per degree) for both pupil diameters. Especially for the greater pupil diameter the lenses show tolerance of image quality to lens decentration.

CONCLUSIONS

Both IOLs show only a slight decrease in image quality with decentration and the range of tolerable decentration is increased compared to aspherical IOLs of the first generation.