PCO incidence with hydrophobic acrylic IOLs higher over long term than previously shown, study finds

Information about posterior capsule opacification (PCO) rate can be helpful to surgeons as they choose IOLs for their patients. Use of the results of a study presented by David J. Apple, MD, of Charleston, SC, will require a paradigm shift, however, he said; the study found somewhat lower rates of PCO resistance with a posterior-chamber lens of hydrophobic acrylic material compared with rates found in previous studies, especially in the late postoperative period.

The first-of-its-kind study included 5,000 lenses examined from 1981 to 1999 and 500 lenses examined from 2004 to 2008 using the Miyake-Apple posterior technique. The investigators separated the lens styles by manufacturer and model number.

They evaluated eyes, paying particular attention to PCO and postoperative proliferation of cells, using criteria that included Soemmering's ring intensity, Soemmering's ring area, peripheral and central PCO, and rate of posterior capsulotomy. They ranked IOL models based on the degree of complications affecting each lens. The researchers found low scores in the early postoperative period with the hydrophobic acrylic designs, but they saw no differences in the scores with all biomaterials in later stages.

The safety and efficacy of a lens depends on the avoidance of opacification and fibrosis, Dr. Apple said.

"The matter of avoidance is not inherent in any IOL," he said. "Basically, you're only delaying it. After 3, 4, 5 years, [all the lenses are] the same as far as I can see. . . . That's an important point."