Device provides option for selected glaucoma patients

Ed Edelson

New York-The Ex-PRESS glaucoma implant (Optonol) is a device that may be coming into its own, at least for some selected patients undergoing glaucoma surgery, Robert D. Fechtner, MD, reported at the Glaucoma 2006 meeting here.

"At one point I had taken out more of these than I had put in," said Dr. Fechtner, director of the Glaucoma Division at the University of Medicine and Dentistry of New Jersey (UMDNJ)-New Jersey Medical School, Newark. "The balance has shifted now."

The device "came on the market in search of a clear indication," Dr. Fechtner said. The glaucoma implant is designed to divert the aqueous humor from the anterior chamber to the subconjunctival space to form a filtration bleb.

"My initial experience was with patients who were at high risk for failure of trabeculectomy as an alternative to a standard glaucoma drainage device," he said. "But the original Ex-PRESS procedure was associated with a number of complications, such as hypotony and having the anterior chamber go flat.

"One report by (Dr. Carlo E.) Traverso published in the British Journal of Ophthalmology in 2005 of ExPRESS combined with cataract surgery showed good pressure control," he said of one study of 26 eyes. "The overall success rate of about 80% looks good, but there were early postoperative complications-we have learned to expect hypotony, flat chambers, hyphemas, and device dislocations."

While early experience with the full-thickness procedure indicated "don't do it," further experience shows the device now can be "an acceptable adjunct or alternative to standard trabeculectomy when placed under a scleral flap," Dr. Fechtner said.

Use of the device is growing, with several surgeons having implanted 100 or more under a scleral flap, Dr. Fechtner said.

"We're getting the information we need to evaluate this procedure," he said.

He cited a study by Dahan published in Journal of Glaucoma in 2005 in which the device was implanted in 24 eyes of 23 patients. After 2 years, the mean pressure was "reduced from 27.2 mm Hg preoperatively to 14.2 mm Hg," Dr. Fechtner said.

"This device seems to work when placed under a scleral flap, but why bother if trabeculectomy does as well?" he asked.

The differences: It allows the physician to eliminate two steps, making the sclerectomy and making the iridectomy.

"I can eliminate two steps of my procedure, so there is a case for thinking of this for, say, patients who are at risk for bleeding or those who have had complicated cataract surgery with vitreous behind the pupil," Dr. Fechtner said.

He cited the case of a 90-year-old male patient who was taking anticoagulants. When the medication was discontinued for a previous operation, the patient suffered a stroke.

"We were not going to stop the anticoagulants and risk his health or his life," Dr. Fechtner said. "I performed the surgery with topical anesthesia with a very small incision and flap. After implanting the device under the scleral flap, the early postoperative pressure was 8 mm Hg and the chamber was deep.

"There is a potential advantage of using the device in selected patients," Dr. Fechtner said. "There is no sclerectomy, no iridectomy, the eyes are very quiet.