INNOVATION

New Arrival: Tecnis Symfony IOL

BY MARIA SCOTT, MD

Artificial accommodation, the Holy Grail, is still not within our reach. The 20-year-old emmetrope who can see in any lighting condition at any distance is certainly someone to envy. Our patients older than 40 and our cataract patients want that vision. In the not-too-distant future, we will be one step closer to giving cataract patients continuous range of vision. The Tecnis Symfony IOL, approved by FDA in July, is a first-of-its kind lens that is intended to provide patients a continuous range of vision, including far, intermediate, and near distances. It will be available on a spherical and astigmatism-correcting platform.

Until now, multifocal IOLs of different designs split the light into several focal areas, and accommodative IOLs change their shape when the ciliary muscles contract. The multifocal lenses of today are more like bifocals, giving patients excellent distance vision and a near vision focal point that can be tailored to the patients needs. Alcon’s ReStor lens was the first diffractive multifocal IOL on the U.S. market. Since its introduction, asphericity and varied focal lengths for near vision have been approved. Increased options to Abbott’s ZMBOO with the ZLBOO and the ZKBOO have improved patient satisfaction with more traditional focal lengths and a reduction in halos and glare. But halos and glare are still a problem, and hitting the refractive target of plano is still not 100% obtainable.

Abbott’s Tecnis Symfony ZCR00 extended focus lens may help us to provide our patients with a more continuous range of vision and a glare and halo profile that is similar to a monofocal lens. And because of its extended focus, the Symfony IOL may be more forgiving of target misses.

A New Multifocal IOL

The Tecnis Symfony IOL, with its proprietary technology, achieves one elongated focus area by implementing two technologies: a diffractive optic design that extends the length of focus and an achromatic technology that reduces chromatic aberration. The hydrophobic acrylic lens has an optical anterior surface that is aspheric biconvex and wavefront designed. Its posterior surface is diffractive achromatic for enhanced contrast sensitivity and has echelette features to extend the range of vision. It is a one-piece 6.0-mm optic with an overall diameter of 13.0. It’s optical A constant is 119.3 and its ACD 5.7. It will be available in 0.5D steps from a range of 5.0-34.0 D.

The Tecnis Symfony ZXT series is the toric version: ZXT150 (1.03D on corneal plane), ZXT225 (1.54D on corneal plane), ZXT300 (2.06D on corneal plane), and ZXT375 (2.57D on corneal plane). This is the first multifocal IOL in the U.S. that will have the ability to correct astigmatism. Its toric platform will increase the number of patients who can enjoy the benefits of this lens; the majority of patients with astigmatism will be able to choose this lens instead of deciding between distance and near vision. The elongated focus leads to the continuous range of high-quality vision.

A Few Cautions

There are some cautions when using this lens because of its range of focus. Automatic refractors may not provide reliable results. Manifest refractions with maximum plus technique are recommended.

Although mild visual effects (such as halos and glare around lights) may occur, preclinical evaluation indicated that these phenomena are comparable to those of a standard monofocal lens.

Big Benefits

I believe adding this new lens to our armamentarium will improve our results with presbyopia-correcting IOLs. The Symfony lens should provide high patient satisfaction and reliability with a low number of complaints (halos and glare and missed refractive outcomes). Because it comes on a familiar platform, the learning curve for surgery center staff should be minimal. I look forward to having the Tecnis Symfony lens available for my patients. ■

References & Resources

Maria Scott, MD, is founder and medical director of Chesapeake Eye Care & Laser Center, Annapolis, Md.