Posters

Refractive changes and wavefront aberrations of polyfocal intraocular lens during focusing on far and near target measured by iTrace visual function analyzer

Poster Details

First Author: J.Kopriva CZECH REPUBLIC

Co Author(s):    E. Adamusova   Z. Mazal           

Abstract Details

Purpose:

Clinical evaluation of long term (2 to 6 years) functional results in ocular wavefront aberrations and refractive changes during focusing on far and near target after implantation of a bioanalogic, polyfocal intraocular lens WIOL-CF.

Setting:

Department of Ophthalmology, Hospital Mlada Boleslav, Czech Republic Department of Ophthalmology, Hospital Most, Czech Republic Department of Ophthalmology, Hospital Strakonice

Methods:

Evaluation was performed by iTrace (Tracey Technologies, USA) Visual Function Analyzer. The patients were asked to look at two different distances - far target and near optotype at 30 cm - and at the same time wavefront measurements and corneal topography were performed. iTrace software enables comparison/differences of same eye data between two exams (far/near focus) and evaluate accommodation amplitude. Peak accommodation values show maximum optical power add (myopic shift) in a particular small area of the lens. Mean accommodation values show the average of the optical power add (myopic shift) in the whole area measured. Zernike coefficients were obtained and analysed.

Results:

To the study were enrolled 36 patients (49 eyes) from 3 centres in this prospective study. All patients were > 2 years (2-6 years) after uneventful implantation of WIOL-CF intraocular lens. More than 70% of eyes achieved objectively measured accommodation that is in clinical practice further supported by polyfocality and pseudo-accommodation driven by pupil size. Mean peak accommodation value of 3.09 D (from 1.70 D to 7.29 D) and mean spherical equivalent change of 0.82 D (from -0.42 D to 1.85 D) were observed. The far and near vision wavefronts differ mainly in defocus and astigmatism. Less important changes in higher order ocular aberrations were also observed due to accommodative effort.

Conclusions:

iTrace measurements detected changes in the optical power characteristics driven by the dynamic physical change of the IOL even after long-term follow-up (2-6 years). The magnitude of measured changes corresponds with clinically measured accommodative range of above 2 D. The changes in refraction are driven mainly by LO aberrations. The measured refractive changes during far/near stimuli further complements WIOL-CF polyfocality and pseudo-accommodation driven by the pupil size as mechanism which enable good vision to all distances. Limited sample size asks caution in generalization of the conclusions and need to be verified in further studies. FINANCIAL INTEREST: One of more of the authors... is employed by a forNONEprofit company with an interest in the subject of the presentation