Hydrophobic acrylic IOLs have gained significant market share around the world. These lenses are increasing in popularity among ophthalmologists because they offer good mechanical stability, good uveal biocompatibility, and low rates of posterior capsular opacification (PCO).
In Europe, a wide variety of IOL designs made of 25% or 26% water content hydrophilic acrylic materials is available from numerous manufacturers. Hydrophilic acrylic IOLs have numerous advantages. They are relatively easy to manufacture, the raw materials are easy to obtain, the material is highly compressible due to its water content, and their mechanical properties are not temperature-dependent. However, hydrophilic acrylic IOLs are associated with higher rates of PCO formation, and they do not perform as well as the best hydrophobic acrylic and silicone IOLs available today. of monomer mixtures. Depending on the mixture, hydrophobic lenses have different characteristics in terms of refractive index, presence of vacuoles, surface tackiness, temperature dependence for mechanical stability, and tensile strength. Additionally, the IOL's design and injection system are important to its overall performance.
Historically, large companies such as Abbott Medical Optics Inc. (Santa Ana, California), Alcon Laboratories, Inc. (Fort Worth, Texas), and Hoya (Tokyo) have been the primary developers of hydrophobic acrylic IOLs. These three companies have released several hydrophobic acrylic IOL models over the past 15 years. This past year, several manufacturers that previously made only hydrophilic acrylic lenses have introduced true low water content hydrophobic acrylic IOLs. It appears that other companies also plan to launch hydrophobic acrylic lenses in the near future.
Table 1 lists the newest hydrophobic acrylic IOLs available on the European market. With the promise of additional hydrophobic acrylic technologies to become available, CRST Europe will keep you abreast of their arrival in future issues.
Khiun F. Tjia, MD, is an Anterior Segment Specialist at the Isala Clinics, Zwolle, Netherlands. Dr. Tjia states that he is a consultant to Alcon Laboratories, Inc., and Hoya. He is the Co-Chief Medical Editor of CRST Europe. Dr. Tjia may be reached at e-mail: kftjia@planet.nl.
