The role of needle revision and 5-fluorouracil application over the filtration site in the management of bleb failure after trabeculectomy: a prospective study

Abstract

Fifty-three eyes of 49 consecutive patients with an intraocular pressure (IOP) over 21 mmHg; without bleb or with a thick, flat bleb after the second postoperative week following trabeculectomy were included in the study. Needle revision was performed with a 26-gauge tuberculin syringe containing 5 mg (0.2 ml) 5-FU in a period of 2 weeks to 10 months postoperatively after unsuccessful digital massage and/or laser suture-lysis. 5-FU injection was not performed when a bleb formation was observed during needling. In case of no bleb formation, 5-FU was injected subconjunctivally over the scleral flap area and repeated a maximum of six times until a functioning bleb was maintained. Needle revision was successful in 14 of 53 eyes (26.4%) as an initial procedure and nine (16.9%) eyes maintained success. Forty-four eyes (83.1%) had 5-FU injection since needle revision did not provide bleb formation (39 eyes) or did not maintain initial success (five eyes). Mean IOP was 27.8+/-4.7 mmHg (range, 22-41) before any intervention and decreased to 20.5+/-4.8 mmHg (range, 8-35) after a mean follow-up of 25.1 months and the difference was statistically significant (p<0.001). Mean IOP after needle revision in 14 patients was 18.9+/-4.9 mmHg (range, 8-29) and 16.3+/-3.7 mmHg in nine out of 14 patients that maintained success. Mean IOP after the last 5-FU injection was 21.4+/-4.6 mmHg (range, 13 to approximately 35 mmHg). The mean number of 5-FU injections was 2.4 (range, 1-6). During a mean follow-up of 25.1 months (range, 1-48 months), three eyes (5.7%) had diffuse corneal punctate epitheliopathy lasting for 3-4 weeks and subconjunctival hemorrhage was seen in nine eyes (17%). Needle revision and/or subconjunctival injection of 5-FU over the bleb area is a safe, relatively efficient approach with a low rate of complications to overcome the early and mid term bleb failure after trabeculectomy.