Abstract
Purpose: :
To evaluate the performance of single-element (1E) and dual-element (2E) translating AIOL in terms of longitudinal chromatic aberration (LCA) in a model eye and propose a method of achromatization.
Methods: :
Paraxial thin-lens equations of chromatic aberration were used. A method of achromatizing pseudophakic model eyes for distance and near foci was developed and evaluated. Result from paraxial analysis was verified by finite ray-tracing analysis in a finite model eye using optical design software. LCA of the model eye implanted with 1E or 2E-AIOL was calculated at various accommodation levels.
Results: :
Chromatic aberration of a pseudophakic eye depends on the dispersive property of the AIOL. Effect of accommodation on LCA is minimal. Total chromatic defocuses of the pseudophakic model eye were 0.75D and 0.73D at distance focus for PMMA made 1E & 2E-AIOL and 0.77D and 0.75D with 2.5D accommodation. Achromatization of the model eye with 1E-AIOL required extreme value of V-number. It was achieved with 2E-AIOL with combination of front PMMA element and rear element with a minimum V-number of 29.01.
Conclusions: :
Accommodation increases the chromatic defocus but clinical significance of the amount needs to be verified. Achromatization of the pseudophakic eye appears impractical with currently available ophthalmic materials.
Keywords: accomodation • intraocular lens • aberrations