Prospective evaluation of preoperative factors associated with successful mitomycin C needling of failed filtration blebs

Abstract

Purpose: To study the long-term effectiveness and factors involved in successful needling of failed filtration blebs with mitomycin C (MMC).

Materials and methods: We conducted a prospective, nonrandomized comparative trial that included 34 consecutive patients (34 eyes) who underwent mitomycin C needling of a failed filtering bleb after trabeculectomy followed by a 0.01 mL injection of mitomycin C (0.2 mg/ml). The success of the needling revision was defined as absolute if the intraocular pressure (IOP) was < 21 mm Hg without antiglaucoma medications and qualified if the IOP was < 21 mm Hg with antiglaucoma medications. Preoperative and perioperative factors were evaluated for an association with postoperative success using Kaplan-Meier survival analysis.

Results: The mean follow-up was 14.2 +/- 9.8 months. The mean preoperative IOP was 25.5 +/- 4.4 mm Hg, which decreased to 11.1, 13.4, 15.8, 16.7, 14.9, 14.1, 13.9, and 13 on postoperative day 1, postoperative week 1, and after 1, 3, 6, 9, 12, and 24 months, respectively (P = 0.001 for each comparison). At the final visit, success was absolute in 15 eyes (44.1%) and qualified in 14 eyes (41.2%). The success rates were 90% and 75% at 1 and 2 years, respectively. The success of the needling procedure was highly correlated with glaucoma filtration surgery performed less than 4 months previously (Kaplan-Meier analysis, log-rank test P = 0.006).

Conclusions: Mitomycin C needling revision appears to have a high long-term success rate. Surgery performed less than 4 months previously contributes to the success of the initial mitomycin C needling procedure.