Purpose:The purpose of this study was to assess the results of bleb needling in glaucomatous patients with late failed filtering blebs.Materials and Methods:A retrospective case series of 27 eyes of 27 patients was considered. All patients underwent needle bleb revision with adjuvant mitomycin-C performed at the slit lamp, during an office visit. Complete success was defined as postneedling intraocular pressure (IOP) ≤ 21 mmHg without any antiglaucoma medications and qualified success was IOP ≤ 21 mmHg with topical antiglaucoma medications.Results:There were 12 eyes with encapsulated blebs and 15 eyes with flat blebs. The mean interval between index filtering surgery and bleb revision was 32.74 ± 15.36 months. Mean IOP was 25.07 ± 4.80 mmHg before surgery and 19.66 ± 4.97 mmHg at last postoperative follow-up. The mean follow-up was 20.31 ± 15.63 months. Complete and qualified successes were 7.4% and 51.9%, respectively. Cumulative rates of success at 1, 2, 3, and 4 years were 76%, 65%, 49%, and 37%, respectively. The mean number of antiglaucoma medications was reduced from 3.15 ± 0.36 preoperatively to 2.33 ± 1.21 postoperatively (P<0.001).Conclusion:Slit-lamp needle revision in office is a simple and effective method for treating late encapsulated or flat filtering blebs without significant complications even for late bleb failure.