Results of medical management and mitomycin C-augmented excisional bleb revision for encapsulated filtering blebs

BACKGROUND AND OBJECTIVE: To assess the outcome of medical management and mitomycin C (MMC)-augmented excisional bleb revision (EBR) for encapsulated filtering blebs. PATIENTS AND METHODS: The author conducted a retrospective study of 503 patients who had undergone trabeculectomy performed over a 5 year period, followed up for at least one year, in order to identify the encapsulated filtering blebs. Mitomycin C-augmented (0.4mg/ml for 3 minutes) EER was performed in cases of failed medical therapy for managing encapsulated blebs consisting of antiglaucoma medications, topical steroids, and digital compression. RESULTS: An encapsulated bleb developed in 18 eyes (3.6%) of 503 patients. Identification of bleb encapsulation occurred at a mean follow-up time of 24.2 +/- 10.4 days after surgery. The mean intraocular pressure (IOP) at that point was 30.4 +/- 11.7 mmHg in the affected eyes. Fifteen (83.3%) of 18 eyes responded to conservative management and 3 eyes (16.7%) required MMC augmented EER. The mean IOP reduced from 30.4 +/- 11.7 mmHg to 14.2 +/- 4.2 mmHg after a mean follow-up of 37.6 +/- 11.4 months in the conservative management group, while it reduced from 37.3 +/- 23.4 mmHg to 12.0 +/- 4.4 mmHg after a mean follow-up of 42 +/- 6 months in the surgically treated group. None of the surgically treated eyes developed MMC-related complications. CONCLUSION: Conservative management is very effective in the treatment of encapsulated filtering blebs. The intraoperative use of MMC is a safe and effective adjunct in EER in cases where conservative management has failed.