PARIS — Research throughout the years has shown that posterior capsule opacification is a complex complication with many factors that affect occurrence, a physician said here.

David Spalton

David Spalton, FRCS, FRCP, FRCOphth, delivered the Ridley Medal Lecture during the opening ceremony of the European Society of Cataract and Refractive Surgeons meeting. He outlined the occurrence of PCO since the first IOL implantations. By the 1990s, cataract surgery had become the most common surgery in the Western world, with PCO the most common complication, he said.

Research throughout the years has shown that reasons for the occurrence of PCO are multifactorial and can be affected by a patient's age, coexisting disease, surgical technique used in cataract surgery and lens design of the implanted IOL.

"We have come a long way," Dr. Spalton said. "There is more to PCO than just life or death on the posterior capsule."

Dr. Spalton cited Ekkehard Medhorn, MD, and his finding that patients implanted with the AcrySof IOL (Alcon) had clear posterior capsules. He said the discovery was a major milestone in the history of cataract surgery because it demonstrated that PCO was not an "inevitable complication after operation."

In 1999, O. Nishi, MD, showed that a square-edge lens profile prevented PCO, another key discovery, Dr. Spalton said. However, further research has shown that PCO is not avoided in all square-edged lenses.

"What we need are lenses with an effective optic-haptic junction with a 360° square-edge barrier to give you clear capsules," he said.