The Impact of IOL Abbe Number on Polychromatic Image Quality of Pseudophakic Eyes
Received 1 October 2019
Accepted for publication 20 January 2020
Published 11 August 2020 Volume 2020:14 Pages 2271—2281
Checked for plagiarism Yes
Review by Single anonymous peer review
Peer reviewer comments 2
Editor who approved publication: Dr Scott Fraser
Arthur Bradley,1 Renfeng Xu,1,2 Huachun Wang,2 Matt Jaskulski,1 Xin Hong,3 Nicolette Brink,3 Stephen Van Noy3
1School of Optometry, Indiana University, Bloomington, IN 47405, USA; 2Department of Ophthalmology and Vision Science, University of Nebraska Medical Center, Omaha, NE 68198, USA; 3Alcon Research Laboratories, Fort Worth, TX 76134-2001, USA
Correspondence: Arthur Bradley
Indiana University, 800 E Atwater Ave, Bloomington, IN 47405, USA
Tel +1 812-855-2465
Fax +1 812-855-7045
Purpose: The human eye exhibits large amounts (2.5 diopters) of longitudinal chromatic aberration (LCA). Its impact on polychromatic image quality, however, has been shown experimentally and by computer modeling to be small or absent. We hypothesized that modest changes in pseudophakic LCA created by higher and lower Abbe number materials will have little or no impact on polychromatic image quality in pseudophakic eyes.
Materials and Methods: Using published chromatic and monochromatic aberration data from pseudophakic eyes and higher and lower Abbe number materials (37 and 55), we computed monochromatic point spread functions for 21 wavelengths across the visible spectrum. After weighting by either the RGB spectra of a liquid crystal display or by a flat white spectrum, they were weighted by the human spectral sensitivity function (Vλ) before being added to generate polychromatic PSFs.
Results: In the absence of monochromatic aberrations, the reduced LCA due to higher Abbe number intraocular lens (IOL) materials resulted in a reduction of 0.08 diopters in the mean defocus generated by LCA. At the retinal plane, the higher Abbe number pseudophakic model produced improvements in polychromatic modulation transfer functions (MTFs) similar to those generated by a 0.05 diopter reduction in spherical defocus. When monochromatic aberrations were added to make the model more representative of actual pseudophakic eyes, the differences in image quality became sub-threshold for human vision or disappeared completely.
Conclusion: The anticipated gains in polychromatic image quality from employing higher Abbe number IOL materials with reduced LCA do not materialize in plausible aberrated models of pseudophakic eyes.
Keywords: Abbe number, chromatic aberrations, IOL, image quality