Late onset bleb leakage should be managed carefully

New Orleans-Late onset bleb leakage usually occurs 2 to 3 years after glaucoma filtering surgery with an incidence between 2% and 9%. This condition warrants treatment, according to Philip P. Chen, MD, who spoke during the glaucoma subspecialty day meeting.

Late onset bleb leaks have been associated with blebitis and bleb-related endophthalmitis, both vision-threatening complications.

"Poor vision can result if the leak causes hypotony maculopathy, choroidal detachments, corneal folds or edema, or fluctuation of refractive error," Dr. Chen said.

Possible conservative treatments include maximal aqueous suppression with up to three medications, pressure patching or the use of an oversized contact lens, trichloroacetic acid, cyanoacrylate glue, or argon laser.

"The use of topical antibiotics to incite inflammation or to cover for possible infection is contraindicated," said Dr. Chen, who is affiliated with the University of Washington, Seattle.

More invasive treatment may be required in combination with aqueous suppression. These include intra- and peri-bleb autologous blood injection, compression sutures using 9-0 or 10-0 nylon, and Nd:YAG laser in continuous wave-mode.

Surgical techniques may be necessary, such as bleb needling, conjunctival advancement, conjunctival autograft, and the placement of a glaucoma drainage device.

Bleb leaks might be prevented with the use of fornix-based trabeculectomies and the application of antifibrosis agents over large surfaces, Dr. Chen said. This will produce thicker, diffuse blebs, he said.