Implanting iris prosthesis is ‘in the bag’

San Francisco-Early data on an artificial iris implant suggest positive clinical and cosmetic outcomes. Findings from a retrospective non-comparative case series of 74 eyes in 57 patients offered positive results for patients who received a custom flexible silicone prosthesis for iris defects resulting from a variety of different causes.

The device is approved for use in Europe, said Michael Snyder, MD, Cincinnati Eye Institute, Blue Ash, OH, but has not been approved for marketing in the United States.

The artificial iris is made by HumanOptics in Erlangen, Germany. Each silicone device is custom-made for the patient. When possible, the surface design is based on a photograph of the iris or the iris in the contralateral eye. The most common indications for implantation are trauma, excision of iris melanoma, congenital aniridia syndrome, iridocorneal-endothelial syndrome, and irises destroyed by inflammatory disease.

Each artificial iris is manufactured 12.8 mm in diameter with a 3.35 central aperture. The surgeon typically cuts the implant to the appropriate size with a trephine. Once the device has been cut to size, it is folded in thirds, inserted in a standard injector, and placed in the capsular bag. In this series, device implantation was combined with phacoemulsification and IOL in phakic patients or capsular bag reopening in pseudophakic patients in order to achieve a successful in-the-bag placement.

“We had a fairly broad age range of patients,” Dr. Snyder said. “And we found that boys hurt themselves more than girls and needed iris replacement.”

The patients were followed for a mean of 17.5 months, he continued. Iris defects in the series included congenital aniridia (53%), trauma (27%), iris tumor resection (11% and others (9%). Centration within the bag was successful in all of the patients.

Corrected distance visual acuity improved from 1.3 to 0.69 logMar. Glare improved from 2.42 on a three-point scale to 0.18 and photophobia fell from 2.52 to 0.22. The devices were repositioned in a total of eight eyes, four as a pre-planned procedure and four due to complications. A total of 15% of eyes had complications that were unrelated to the device. The average endothelial cell dropped by 10% percent by the final follow-up and four patients required corneal endothelial keratoplasty.

“Snellen acuity improved remarkably in our group,” Dr. Snyder said. “And 100% of our patients had a better cosmetic appearance. In-the-bag implantation of this flexible silicon prosthesis is effective and successful in managing glare and photophobia.