Surgical revision of failed filtration surgery with mitomycin C augmentation

The aim of the study was to assess the outcomes of surgical revision with reopening of the scleral flap in eyes with failed glaucoma surgery and adjunctive mitomycin C (MMC).

Retrospective, noncomparative, interventional case series. Fifty-four eyes of 54 consecutive patients with previously failed trabeculectomy or deep sclerectomy who underwent formal surgical revision (23 with concurrent phacoemulsification) were included. MMC, 0.2 mg/mL for 2 to 3 minutes, was applied under a fornix-based conjunctival flap. The preexisting scleral flap was dissected open to reestablish filtration.

Mean follow-up was 39.5+/-10 months. Kaplan-Meier survival analysis showed that the probability (with 95% confidence intervals) of maintaining an intraocular pressure (IOP) between 5 and 18 mm Hg and 20% decrease from preoperative IOP was 64% (47% to 76%) with medications and/or needle revision and 38% (26% to 53%) without, 3 years after surgery. Mean IOP before surgery was 23.6+/-7.2 mm Hg and 14.4+/-6.0 three years after surgery (last IOP before further glaucoma procedure carried forward). Needle revision for bleb failure or high IOP was carried out in 23 eyes (42.5%) and further glaucoma surgery in 5 eyes (9.3%). Patients were on an average of 2+/-1.1 glaucoma medications before surgery. At last follow-up, the number of medications had decreased to 0.8+/-1.2 (P<0.000), with 23 eyes (42.5%) requiring medications to control IOP. Significant complications included delayed suprachoroidal hemorrhage (3 eyes, 5.6%), delayed bleb leaks (5 eyes, 9.3%), hypotony (2 eyes, 3.7%), and blebitis (2 eyes, 3.7%).

There is a progressive increase in IOP with time after surgical revision of failed glaucoma surgery with adjunctive MMC. A significant proportion of eyes will eventually require a needle revision procedure and/or glaucoma medications to further lower IOP. Also, there is a significant incidence of complications associated with this procedure.