IOLs: What Every Surgeon Needs to Know | Ep. 1: IOL Biomaterials

IOLs: What Every Surgeon Needs to Know is an editorially independent video and podcast series from Ophthalmology Times, hosted by Douglas D. Koch, MD, Professor and Allen, Mosbacher, and Law Chair in Ophthalmology at the Cullen Eye Institute, Baylor College of Medicine in Houston, Texas.

In each episode, Koch will be joined by different expert guests to discuss cutting-edge advancements in intraocular lens (IOL) technology and cataract surgery. In this inaugural episode, Koch is joined by Liliana Werner, MD, PhD, Benning Presidential Endowed Chair and co-director of the Intermountain Ocular Research Center at the Moran A. Eye Center at the University of Utah in Salt Lake City, to explore IOL biomaterials.

Setting the stage: What today’s IOLs are made of

Werner begins with an overview of current material categories, noting, “there are two classes of biomaterials currently being used… acrylic or silicone lenses.” She explains that acrylics can be rigid polymethyl methacrylate (PMMA) or foldable hydrophilic or hydrophobic designs, and emphasizes that “these are just general classes of materials,” with copolymer variation driving differences in refractive and mechanical properties.

Discussing geographic practice patterns, Koch observes, “in the US, we use a lot of hydrophobic foldable acrylics,” while hydrophilic acrylics are more common in Europe. Werner attributes this partly to calcification risk, noting, “I see them every single week because we receive explanted lenses from everywhere in the world.” She describes localized calcification associated with secondary surgeries and cautions, “do we always know if our patients are going to need a secondary surgery down the road?”

IOL calcification: Clinical patterns and risk factors

Werner also addresses silicone IOL calcification in asteroid hyalosis and contrasts this with hydrophobic acrylics, stating, “I never saw one case of calcification of hydrophobic acrylic lens, proved by a laboratory analysis.” She highlights newer hydrophobic acrylic materials with higher water content that are “not prone to hydration-related phenomena, like glistenings and subsurface nanoglistenings,” which can contribute to light scatter.

The conversation turns to postoperative refractive adjustment with the light adjustable lens. Werner explains that near-UV light can change lens power and stresses that “the patients really have to wear those UV protective glasses until the final locking of the power of this lens.”

What’s next in IOL biomaterials

Looking forward, Werner discusses cross-linked polyisobutyl as an emerging material with promising optical and mechanical characteristics, citing early preclinical and clinical data. Koch concludes that “it’s great to know that we have great materials and more coming,” underscoring the evolving landscape of IOL biomaterials.

Douglas D. Koch, MD
E: [email protected]
Koch is Professor and Allen, Mosbacher, and Law Chair in Ophthalmology at the Cullen Eye Institute, Baylor College of Medicine in Houston, Texas.

Liliana Werner, MD, PhD
E: [email protected]
Werner is Professor of Ophthalmology and Visual Sciences; H.A. and Edna Benning Presidential Endowed Chair; and Co-Director, Intermountain Ocular Research Center at John A. Moran Eye Center at University of Utah in Salt Lake City, Utah. The Intermountain Ocular Research Center has performed contract research studies for different companies manufacturing IOLs.