Accommodating power

These developments include presbyopia-correcting IOLs which provide a treatment option for presbyopic patients who do not qualify for laser refractive surgery and do not want to rely on reading glasses.Presbyopia-correcting lenses can be divided into three broad categories: multifocal IOLs, extended depth of focus IOLs, and accommodative IOLs.

accommodating power-8

This is in contrast with multiple zones of optical power in a multifocal IOL that can result in scattering of light and visual disturbances.

EDF lenses, while providing preserved visual quality with fewer halos, can still produce a relatively unique photic phenomenon generally described as starbursts.

Reduced visual quality and visual phenomena such as halos, glare, and starbursts are characteristic of multifocal IOLs due to the light scatter that naturally occurs when transitioning between near and far zones .

In a prospective study of 95 eyes comparing multifocal IOLs to monofocal IOLs, 29% of multifocal patients reported glare while 25% reported halos, compared to 19% and 12% in the monofocal group, respectively.

Intraocular lens implants (IOLs) are used in both refractive lens exchange and cataract surgery to replace the natural lens of the eyes and correct for refractive errors.

Over recent years, many improvements in intraocular lenses have allowed for the development of a wide-spectrum of lenses beyond the traditional monofocal lens implants.Trifocal IOLs are popular presbyopia-correcting IOLs in many areas outside of the United States.Compared to the bifocal diffractive IOL, the trifocal IOL improves intermediate vision by providing a third focus.Multifocal IOLs consist of multiple zones of lens power that produce more than one focal point, allowing for enhanced vision at both near and far.Its mechanism of action is based on apodization, in which a near-dominant central area is surrounded by concentric rings of decreasing height that result in diffraction of light at both distance and near.The Symfony IOL (Johnson & Johnson Vision) is an example of an EDF lens that extends the depth of focus through a combination of effects from its echelette design, reduced chromatic aberration and negative spherical aberration.

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