Multifocal and Accommodative Intraocular Lenses

Abstract

Multifocal intraocular lenses (IOLs) have at least two diop tric powers, providing at least two different foci on the same axis. They generate at least two superimposed im ages of each observed object. Image confusion is reduc ed by distant power asphericity, near power apodization, and different distancenear light distribution. At the mo ment, diffractive multifocal IOLs are the most successful. Results show good distance and near visual acuity, reduc ed contrast sensitivity and good patient satisfaction. Ha los and glare are the most frequently reported problems, occasionally causing IOL explantation. Pseudoaccommo dative IOLs are monofocal IOLs that change power with accommodation, usually by forward optic displacement. Their ability to provide good distance and near vision has not been universally confirmed in clinical practice.

Ray propagation imaging and optical quality evaluation of different intraocular lens models

“…Although such IOLs categorically share a multifocal nature, they do differ in their optical quality [5][6][7][8][9] and light distribution behavior [10][11][12], which are dictated by the optical concept and material composition they employ. Understanding their nature and differences in relation to pupil size may help surgeons in choosing the appropriate IOL design for the individual patient.…”

Comparison of visual functions and contrast sensitivities between monoblock hydrophobic acryrlic monofocal and monoblock hydrophobic acryrlic multifocal intraocular lenses

“…In the earlier years, multifocal oils were developed to provide functional near and intermediate vision by increasing the depth of field in the eye. 3 Currently, there are three types of multifocal oils used in clinical practice: multi-zone refractive, diffractive, and a combination of these two IOLs. 3,19 Multifocal diffractive IOLs have concentric rings in the posterior or anterior surface.…”

“…3 Currently, there are three types of multifocal oils used in clinical practice: multi-zone refractive, diffractive, and a combination of these two IOLs. 3,19 Multifocal diffractive IOLs have concentric rings in the posterior or anterior surface. The rings form two primary focal points independent of the pupil size.…”

“…9 With the introduction of novel technologies, incoming light rays are distributed to two principal focal points, near vision and distance vision, or to several foci. 3,5,10,11 However, several optical side effects including decreased contrast sensitivity, glare disability, or the presence of halos, were reported. 8,10,12−18 These effects may significantly affect the patient's visual performance due to decreased retinal image quality.…”

Combining Multimodal Wavefront Examination and Digital Refraction to Create a Rapid and Accurate Approach (XFraction) for a Total Visual System Assessment for Intraocular Lens Selection

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The advances in surgical techniques over several decades have raised expectations among patients with cataracts who expect almost perfect vision and are less willing to accept spectacles for postoperative vision correction. [1][2][3] Refractive cataract surgery involving the implantation of premium intraocular lenses (iols), including multifocal, Toric, or accommodative lenses is currently one of the most common and safest surgical procedures carried out worldwide. in a minority of patients, a level of dissatisfaction can remain largely due to a variability in parameter measurements during refraction calculation that determines iol selection, and this can prevent patients from obtaining their optimal visual performance.

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