Can aberrometry provide rapid and reliable measures of subjective depth of focus following multifocal intraocular lens implantation?

Session Details

Session Title: Multifocal Toric IOLs

Session Date/Time: Tuesday 16/09/2014 | 14:00-16:00

Paper Time: 14:42

Venue: Boulevard A

First Author: : S.Dhallu UK

Co Author(s): :    A. Sheppard   T. Mihashi   T. Drew   S. Shah   J. Wolffsohn  

Abstract Details

Purpose:

To determine whether the ‘through-focus’ aberrations of a multifocal intraocular lens (IOL) implanted patient can be used to provide rapid and reliable measures of their subjective depth of focus.

Setting:

Midland Eye, Solihull, UK

Methods:

Eyes that had been implanted with a concentric (n = 8), segmented (n = 10) or accommodating (n = 6) intraocular lenses (mean age 62.9 ± 8.9 years; range 46-79 years) for over a year underwent simultaneous monocular subjective (electronic logMAR test chart at 4m with letters randomised between presentations) and objective (Aston open-field aberrometer) defocus curve testing for levels of defocus between +1.50 to -5.00DS in -0.50DS steps, in a randomised order. Change in pupil size and ocular aberration (a combination of the patient’s and the defocus inducing lens aberrations) at each level of blur was measured by the aberrometer. Visual acuity was measured subjectively at each level of defocus to determine the traditional defocus curve.

Results:

Subjective acuity across the range of focus examined was accounted for principally by spherical lens power change (24.4% of the variance), with up to 39.4% of the variance explained with the addition of higher order variables, with no influence of pupil size. The correlation between subjective acuity and objectively measured focal power of the eye was higher for the multifocal (concentric: r = 0.755, p = 0.001; segmented: r = 0.712, p = 0.004) than the accommodating IOL (r = 0.580, p = 0.030).

Conclusions:

Zernike components of aberrometry across a range of focal planes partly explain the subjective visual acuity at distance, intermediate and near distances. Refinement of aberrometry metrics may therefore allow more rapid assessment of defocus curves to explain IOL performance, such as under different lighting conditions.

Financial Interest:

NONE