Take-home message: Implantation of the newest Implantable Collamer Lens phakic intraocular lenses (V4b and V4c) did not cause cataract formation in highly myopic patients.
Reviewed by Jose F. Alfonso, MD, PhD
Oviedo, Spain—Cataract formation has been associated with the first phakic IOLs introduced into the marketplace. However, newer models seem to be on the way to solving that problem. The latest models, the Visian Implantable Collamer Lenses (ICL) (models V4b and V4c, STAAR Surgical), did not result in cataract development in any eyes in which they were implanted.
Because ICLs meet a need in the refractive surgery arena for patients with high refractive levels, they have been gaining in popularity and not just because of their effectiveness.
In addition, they are safe, predictable, and provide stable vision for patients with high levels of myopia, hyperopia, and astigmatism.
However, the downside has been development of clinically relevant cataracts in 2.1% of patients in less than a year following implantation and in 2.7% before the 3-year mark, according to the FDA data. The culprit in the development of anterior subcapsular cataracts seems to be the contact between the phakic IOL and the natural crystalline lens.
In light of this, Jose Alfonso, MD, PhD, and colleagues, conducted a retrospective, nonrandomized, clinical study in which they evaluated the performances of three phakic IOLs, the V4, V4b, and V4c models, in 3,420 eyes of 1,898 patients who underwent surgery in one center. The mean patient age was 31.2 years (range, 18 to 50 years). The mean spherical refractive error was -7.27 (range, -26.5 to 12.5 D).
Of the 3,420 eyes, 1,531 were implanted with the V4 phakic IOL, 1,108 with the V4b model, and 781 with the V4c model. The mean follow-up times, respectively, were 6 years (range, 1 to 12 years), 2.0 years (range, 1 3o 3 years), and 6 months (range, 3 to 24 months), according to Dr. Alfonso, associate professor at the University of Oviedo, School of Medicine and head of the Cornea and Lens Department of the Fernández-Vega Universitary Institute, Oviedo, Spain.
He reported that cataracts developed in 21 (0.61%) of 15 patients with the V4 phakic IOL. No cataracts developed in eyes that received the other two phakic IOL models.