Weak zonules require a thorough preoperative and intraoperative surgical plan

SAN FRANCISCO — Cataract extraction in patients with weakened zonules requires preoperative recognition of individuals at high risk and formation of a surgical plan to preserve the capsular bag, which supports the IOL and is a barrier against vitreous prolapse, according to a speaker.

Kenneth J. Rosenthal

Preoperative phakodenesis and iridodenesis are an indication of advanced acute zonule weakness, Kenneth J. Rosenthal, MD, FACS, said during the joint meeting of the American Academy of Ophthalmology and Pan-American Association of Ophthalmology. Other signs, including pseudoexfoliative material in the anterior chamber, may also be indicative, he said.

"Increased retrionoidal space is much more subtle, but is also an important indicator," Dr. Rosenthal said.

Ultrasonic biomicroscopy may show important indicators, such as the natural lens bowing anteriorly, Dr. Rosenthal said.

The surgical protocol should include a plan to protect the capsule, stabilize and support the capsular bag, atraumatic phacoemulsification and atraumatic insertion of the IOL. A capsular tension ring may also be included in the surgical plan, Dr. Rosenthal said.

"The mantra here is, and it's been said many times, insert the capsular tension ring as late as possible and as early as necessary," he said.