Polyfocal intraocular lens WIOL-CF and its pseudophakic accommodation vs pseudoaccommodation

Session Details

Session Title: Pseudophakic IOLs/ Multifocals I

Session Date/Time: Monday 15/09/2014 | 16:30-18:30

Paper Time: 17:56

Venue: Boulevard A

First Author: : M.Hlozanek CZECH REPUBLIC

Co Author(s): :    J. Urminsky              

Abstract Details

Purpose:

The ability of good distance and near vision without correction in pseudophakic patients has been described as pseudophakic accommodation or pseudoaccommodation. There are several factors, which are advocated to contribute to it, such as the pupil size, total and corneal optical aberrations, degrees and axis of astigmatism or the movement/shape change of the intraocular lens (which is considered to be the dynamic component of this phenomenon). The dynamic component is called pseudophakic accommodation, while the static component is called pseudophakic pseudoaccommodation. The surfaces of the natural crystalline lens (NCL) are hyperboloids, which are similar to the surfaces of the WIOL-CF intraocular lens. WIOL-CF shape increases the depth of focus and causes polyfocality of this lens similarly to the NCL. Due to the properties of the material of WIOL-CF intraocular lens (elasticity, low incidence of the lens opacification and/or capsular fibrosis) there exists the potency for pseudophakic accommodation (dynamic component) of this IOL. Both mechanisms (static and dynamic) were observed in patient with WIOL-CF. We designed the study to separate and characterize these 2 components.

Setting:

1 Ophthalmology dpt., University Hospital Motol, Prague, Czech Republic 2 Ophthalmology dpt., University Hospital Kralovske Vinohrady, Prague, Czech Republic 3 Ophthalmology dpt., Bata Hospital, Zlin, Czech Republic

Methods:

To differentiate the rate of dynamic and static mechanisms of accommodation, we examined the monocular accommodative range with and without cycloplegia. The distance subjective refraction was determined prior to the examination of near visual acuity. Then each patient was tested on near visual acuity charts (distance 40 cm, photopic conditions). Corrective lenses were gradually used in range from +3D to -3D in 0.5D steps and near visual acuity was examined on each step. Accommodative range in cycloplegia was examined after administration of short-acting mydriatic drops (cyclopentolate 1%), achieving pupil diameter at least 6mm, leading to paresis of ciliary muscle. The 3mm pinhole occluder was used. The same procedure of near vision testing was repeated. Means for individual defocus points were statistically compared by paired t-test.

Results:

Twelve eyes of 6 patients were examined. Defocus curves significantly differed in all points of defocus curves (p < 0,05). Individual defocus curves from measurements without cycloplegia showed pseudophakic accommodative range of 2D.

Conclusions:

Modern designs of IOLs constantly develop in order to offer maximal spectacles independence for both far and near vision without compromising visual quality. Two core parts of this process are the pseudophakic accommodation (the dynamic component of ocular refractive variation during near vision), and the pseudophakic pseudoaccommodation (the depth of focus and the subjective adaption to defocus during near vision). Despite the low number of patients, we have detected uniform and significant results, which have indicated the presence of dynamic component (pseudophakic accommodation) in our group of patients with WIOL-CF intraocular lens. It can support the pseudophakic pseudoaccommodation of WIOL-CF, derived from the polyfocal optics with continuous depth of focus to restore quality vision for all distances.

Financial Interest:

NONE