Posters

Clinical consequences of MTF-focus-through curves

Poster Details

First Author: P.Hagen GERMANY

Co Author(s):    D. Breyer   H. Kaymak   K. Klabe   F. Kretz   G. Auffarth  

Abstract Details

Purpose:

The aim of this retrospective quality management investigation was to search for correlations between MTF-focus-through curves measured on an optical bench and clinical defocus curves.

Setting:

All MIOL-implantations and follow-ups were performed at the Breyer-Kaymak-Klabe Eyesurgery in Duesseldorf, Germany, which is part of the International Vision Correcton Research Center (IVCRC.net).

Methods:

We compared MTF-focus-through curves with clinical defocus curves (monocular, distance-corrected) for the following groups: a) Comfort with 1.5D addition (Oculentis, 50 eyes), b) Comfort with 2.0D addition (Oculentis, 15 eyes), c) MplusX with 3.0D addition (Oculentis, 15 eyes), d) MiniWell (Sifi, 15 eyes), e) Symfony (AMO, 30 eyes), f) LisaTri (CZM, 20 eyes). MTF curves were assessed with a power and MTF measurement device (Lambda-X) with an aberration free ISO11979-2 eye model at monochromatic green light (546nm wavelength). We varied the aperture diameter and the spatial frequency of the light pattern. Clinical defocus curves were measured with a phoropter.

Results:

At 3mm and 50cy/mm the characteristic multifocal MTF-profiles with sharp peaks become visible, whereas at lower frequencies the peaks usually are broader. The form of the monocular distance-corrected defocus curves roughly follows the form of the focus-through curves. They are, however, “washed out”, i.e. peaks are less pronounced and defocus areas with low MTF-values are “filled up”. A physically reason for this modification is the fact that letters on ETDRS-charts are always superposition of multiple spatial frequencies and wavelengths. On the other hand, of course neural processing in the visual system plays a crucial role.

Conclusions:

The correlations between clinical data from defocus curves and MTF-focus through curves are highly non-trivial. Thus, single MTF-focus through curves alone can only serve as a rough guide for predicting visual acuities after MIOL implantation. FINANCIAL DISCLOUSRE: One or more of the authors receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented, One or more of the authors travel has been funded, fully or partially, by a competing company, One or more of the authors travel has been funded, fully or partially, by a company producing, developing or supplying the product or procedure presented, One or more of the authors receives consulting fees, retainer, or contract payments from a competing company