Few anterior subcapsular opacities progressed to cataracts in long-term lens trial

Between 6% and 7% of eyes fitted with the Visian Implantable Collamer Lens developed anterior subcapsular opacities during a long-term U.S. Food and Drug Administration clinical trial of the lens. However, only 1% to 2% of these opacities progressed to clinically significant cataracts, the author noted.

"Visual outcome following cataract extraction was good," study author Donald R. Sanders, MD, PhD, said.

Dr. Sanders used Kaplan-Meier survival analysis to determine the incidence of symptomatic and asymptomatic anterior subcapsular opacities and clinically significant cataract formation among 526 eyes that had been fitted with the Visian ICL (STAAR Surgical). Follow-up for these eyes averaged 4.7 years. Specifically, 468 eyes (89%), 384 eyes (73%) and 311 eyes (59%) were seen at 3 years, 4 years, and 5 years or later, respectively.

The Kaplan-Meier cumulative probability estimate for anterior subcapsular opacities over 7 or more years of follow-up was 7%; however, only 31 eyes (5.9%) developed these opacities.

Anterior subcapsular opacities usually occurred early, with 58% seen in the first year, 68% in the first 2 years and 74% in the first 3 years, Dr. Sanders noted.

The cumulative probability estimate for clinically significant cataracts over the 7 or more years of follow-up was 2%; however, only seven cataracts (1.3%) were observed.

"The difference between the Kaplan-Meier estimate and the actual observed percentage is due to the fact that the former takes into account the differences in postoperative follow-up time of individual eyes," Dr. Sanders said.

Significant factors for developing cataract were preoperative myopia greater than 12 D and patient age older than 40 years.

No eyes lost best corrected visual acuity after cataract extraction, according to the study, published in the June issue of Journal of Refractive Surgery.