Extended Depth of Focus Intraocular Lenses for Presbyopia

Sruti S. Akella; Viral V. Juthani

Disclosures

Curr Opin Ophthalmol. 2018;29(4):318-322. 

In This Article

Available Extended Depth of Focus Lenses

Currently, the only United States FDA-approved EDOF lens on the market is the TECNIS Symfony (Johnson and Johnson Vision, Jacksonville, FL). It is a single-piece, hydrophobic acrylic, foldable lens with a biconvex, wavefront-designed anterior aspheric surface, and a posterior achromatic diffractive surface with echelette design (intended to extend the range of vision with correction of chromatic aberrations). The lens is pupil-dependent; Camps et al. found that higher-order aberrations increased with increasing pupil size.[10] Its diameter is 13.0 mm with an optical zone of 6 mm. Available power spectrum ranges from +5.0 D to +34.0 D, with an addition of +1.75 D at the IOL plane.

The Mini WELL (SIFI, Italy) is a progressive multifocal aspheric IOL in which spherical aberrations are induced in some specific areas of the IOL optic, thus increasing depth of focus and generating progressive multifocality. The optical zone is divided into three different annular zones: the inner and middle zones have different spherical aberrations with opposite signs; the outer zone is monofocal. This outer monofocal zone has been shown in vitro to enhance distance vision with large pupil apertures.[11] The lens' overall diameter is 10.75 mm. It is commercially available from 0 to +30 D with an addition of +3.0 D.

Unique to the market is the Wichterle Intraocular Lens-Continuous Focus (WIOL-CF) (Medicem, Czech Republic), which is a one-piece polyfocal hyperbolic optic with no haptic elements. Made from a proprietary hydrogel (refractive index 1.43, biocompatible hydrogel 42% water), this lens adheres to the posterior capsule and is designed to mimic the accommodative properties of the young natural crystalline lens. Although studies have shown favorable uncorrected intermediate vision,[12,13] two studies reported a consistent pattern of dislocation of the WIOL-CF in the absence of trauma.[14,15]

Of the small aperture lenses, the IC-8 (AcuFocus Inc, Irvine, CA) is a single-piece hydrophobic acrylic, posterior chamber IOL which incorporates a nondiffractive 3.23 mm diameter opaque mask with a 1.36 mm central aperture. It is commercially available from +15.5 D to +27.5 D.[16]

Another small aperture lens on the market is the XtraFocus Pinhole Implant (Morcher, Stuttgart, Germany), intended for ciliary sulcus implantation as a piggyback lens. The device is made of a black hydrophobic acrylic which blocks visible light but is transparent to infrared light more than 750 nm (to permit retinal examination through the opaque material with optical coherent tomography and scanning laser ophthalmoscope). Its overall diameter is 14 mm with a central pinhole opening of 1.3 mm. It is recommended particularly in the treatment of irregular corneal astigmatism and higher order aberrations caused by radial keratotomy, penetrating keratoplasty, or keratoconus.[17] Available EDOF lenses are summarized in Table 1 and Figs 1–4.

Figure 1.

Commercially available EDOF lenses are depicted, including (a) the Tecnis Symfony IOL; (b) Mini WELL Ready; (c) XtraFocus Pinhole Implant; (d) IC-8.

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