Abstract
Purpose: :
The objective of this study was to measure and evaluate the Higher Order Aberration (HOA) and Spherical Aberration in a population of post-cataract pseudophakic subjects.
Methods: :
Subjects who had previously undergone cataract surgery and primary implantation of an IOL at least 6 months prior to participation in this study were examined at a single visit during which each enrolled eye had the ocular wavefront measurements taken. Wavefront aberration contributed by the optical system was measured using the Bausch & Lomb Zywave (I/II) WaveFront Aberrometer. Wavefront aberration contributed by the cornea was measured using the Bausch & Lomb Orbscan Anterior Segment Analyzer (II/IIz). Wavefront aberration contributed by the IOL for combined IOL models was calculated by subtracting the corneal contribution from the wavefront aberration by the optical system.
Results: :
Spherical Aberration contributed by the IOL at 5 mm pupil was 0.17 compared to 0.20 by the optical system. Eighty-six percents of total Spherical Aberration were contributed by the IOLs. The cornea only contributed 14.0% of total Spherical Aberration. When comparing Vertical Coma and Horizontal Coma contributed by the IOL at 5mm pupil, once again, the major portion of the Comas was from the IOL. In addition, a significant correlation was found between HOA and visual acuity at 5mm pupil and at low contrast condition (p=0.03).
Conclusions: :
The results of this study showed that a major portion of the Coma and Spherical Aberration in the optical system were contributed by IOLs. There was a correlation between HOA and visual acuity at 5mm pupil in low contrast condition, indicating that visual acuity worsened when HOA increased. Future studies should continue to investigative the wavefront aberration contributed by spherical and aspheric IOLs in pseudophakic eyes and the association between wavefront aberration and visual performance.
Keywords: intraocular lens • cataract