Tube fenestrations in Baerveldt Glaucoma Implant surgery: 1-year results compared with standard implant surgery.

PURPOSE: To evaluate the efficacy and safety of tube fenestrations in eyes undergoing polyglactin suture-ligated Baerveldt Glaucoma Implant surgery. PATIENTS AND METHODS: The authors performed a retrospective nonrandomized comparative interventional study of consecutive cases of 111 eyes of 111 patients with refractory glaucoma who received polyglactin (Vicryl) suture-ligated Baerveldt 350 implants as a single procedure. In 69 of these cases (group 1), fenestrations were placed anterior to the ligature using a suture needle. In 42 cases (group 2), no fenestrations were performed. Main outcome measures included intraocular pressure, visual acuity, and complications.
RESULTS: Mean (+/- SD) preoperative intraocular pressure was 36.7 +/- 10.2 mm Hg in group 1 and 28.3 +/- 10.3 mm Hg in group 2 (P <0.001). Postoperative mean intraocular pressure was lower in group 1 than in group 2 at day 1 (20.2 +/- 12.8 vs. 29.3 +/- 1.9 mm Hg, P <0.001) and week 1 (18.3 +/- 10.4 vs. 23.7 +/- 8.6 mm Hg, P = 0.006), but was virtually identical at 1 year (12.7 +/- 4.9 vs. 12.6 +/- 4.4 mm Hg, P = 0.95). Number of glaucoma medications used by group 1 patients was significantly lower up to 3 months (P </=0.05). Complication rates were similar in both groups. After tube opening at a mean of 36 +/- 4.7 days, there was an equal and sustained intraocular pressure reduction in both groups in patients taking a similar number of glaucoma medicines up to 12 months after surgery.
CONCLUSION: Tube fenestrations provide safe and effective short-term intraocular pressure control with fewer glaucoma medications in a ligated nonvalved glaucoma drainage implant, with comparable intraocular pressure control and medications required at 1 year. However, not all patients have sustained reduction of intraocular pressure in the immediate postoperative period with fenestrations, making the effect somewhat unpredictable.