Correlation of clinical defocus curves with optical quality of multifocal intraocular lenses

Session Details

Session Title: Pseudophakic IOLs: Multifocal II

Session Date/Time: Sunday 08/10/2017 | 10:30-12:30

Paper Time: 10:42

Venue: Room 2.1

First Author: : F.Vega SPAIN

Co Author(s): :    N. Garzon   M. Millan   C. Varon   M. Gil   G. Cardona   F. Poyales     

Abstract Details

Purpose:

To study the performance of bifocal and trifocal intraocular lenses (IOL) by analyzing the association between the visual acuity (VA) at different levels of defocus of pseudophakic patients implanted with said IOLs, and the through-focus optical quality of the IOLs obtained in-vitro in a model eye.

Setting:

Universitat Politècnica de Catalunya, BARCELONATECH, Spain. IOA Madrid Innova Ocular, Madrid, Spain. Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Spain.

Methods:

Defocus VA (LogMAR) curves were measured between -5.0 diopters (D) and +3.0 D in 0.5D steps in patients bilaterally and symmetrically implanted with one of four diffractive multifocal IOLs: bifocal Tecnis ZLB00 (34 eyes), trifocal Reviol TRI-ED (30 eyes), trifocal FineVision (21 eyes) and trifocal ATLisa Tri (15 eyes). The through-focus optical quality of these multifocal IOLs was tested in-vitro in a model eye by means of the area under the Modulation Transfer Function (AMTF). Consequently, for each defocus level a pair VA - AMTF was obtained, whereupon the association between both magnitudes was investigated.

Results:

The relationship between the AV and the AMTF could be well fitted with exponential decay functions in the range -4.0D to +3.0D. The correlation coefficients R2, which illustrate the fidelity of the fitted model, were: Tecnis ZLB00 R2=0,90 , Reviol TRI-ED R2=0,93, FineVision R2=0,91 and ATLisa Tri R2=0,92. For all the studied IOLs, there is an asymptotic value of 0.0 LogMAR for the best attainable VA, the latter revealing a saturation condition: once certain good level of AMTF has been reached, further improvements in the optical quality of the IOL barely translate into minute improvements of VA.

Conclusions:

In patients implanted with bifocal and trifocal IOLs, the relationship between the VA at the different defocus levels and the trough-focus optical quality of the same IOLs measured with the AMTF, fitted well to exponential decay functions with an asymptote at VA 0.0 LogMAR. This explains why differences in best AMTF (and thus in optical quality) found among the IOLs did not translate into significant differences in the best VA attained by patients.

Financial Disclosure:

NONE