Bleb excision with free conjunctival patch grafting may resolve bleb leak, hypotony after filtration surgery

J Glaucoma. 2011;20(6):392-397.

Free conjunctival patch grafting may be an effective maneuver for bleb repair and hypotony after glaucoma filtration surgery, a study suggested.

According to the authors, the free patch can be measured accurately, is more effective in patients without adequate nearby conjunctiva, prevents conjunctival foreshortening at the fornices and enables direct visualization of the scleral flap. In addition, because the patch is taken from inferior bulbar conjunctiva, it includes healthy tissue.

The retrospective, consecutive, noncomparative case series included 51 eyes with bleb leaks and seven with hypotonous maculopathy without bleb leak. Mean follow-up was 112.65 ± 128.74 weeks. IOP increased from a baseline of 4.41 ± 4.61 mm Hg to 11.98 ± 6.25 mm Hg at 6 weeks and 12.67 ± 4.83 mm Hg at final follow-up.

Complete and qualified success rates were 75.8% and 79.3%, respectively. Failure events occurred in 20.6% of eyes, including two eyes with hypotony, five with elevated IOP and three with bleb leaks.

"Excision of the pre-existing bleb along with a conjunctival patch graft may be superior to conjunctival advancement alone or to autologous conjunctival bleb resurfacing as presence of the pre-existing bleb may lead to an increased incidence of recurrent bleb leaks as a result of retained epithelial inclusions, and to the development of bleb dysesthesia," the study authors wrote.