Outcomes of Ahmed Glaucoma Valve Implantation With Viscoelastic Fill at Both Beginning and End of Surgery

Precis: Intracameral injection of viscoelastic at the beginning of Ahmed FP7 implantation did not reduce early postoperative complication rates. Purpose: To evaluate early postoperative complication rates after a modified technique in which the anterior chamber (AC) is filled with viscoelastic at the beginning of Ahmed FP7 implantation before conjunctival peritomy. Subjects and Methods: A retrospective chart review was performed of eyes that underwent Ahmed FP7 implantation with or without viscoelastic fill to similar to 20 mm Hg by finger tension by a single surgeon (M.R.M). Viscoelastic prevented the AC from becoming shallow at any time during surgery, and additional viscoelastic was injected into the AC at the end of surgery to achieve a final intraocular pressure (IOP) of 20 mm Hg. Results: A total of 159 eyes of 159 patients were included. Mean age was 76.4 +/- 10.4 years. Mean preoperative IOP was 30.3 +/- 9.7 mm Hg on 2.7 +/- 1.2 glaucoma medications. On postoperative day 1, there was an IOP spike >= 30 mm Hg in 0% of patients. Within the first postoperative month, hypotony (<5 mm Hg) occurred in 19 (21.8%) eyes that received viscoelastic fill compared with 5 (13.2%) eyes that did not receive viscoelastic fill (P=0.26). During the early postoperative period (<= 3 mo), there was no difference in AC depth, microhyphema, choroidal effusion, or leakage between the 2 groups (P >= 0.30 for all). There was a higher rate of layered hyphemas in the viscoelastic-fill group at postoperative week 1 (P=0.01). At 3-month follow-up, mean IOP was 14.9 +/- 5.5 mm Hg on 1.6 +/- 0.8 medications in the viscoelastic-fill group and 16.0 +/- 5.2 mm Hg on 1.0 +/- 1.2 medications in the nonviscoelastic-fill group (IOPP=0.35). Compared with baseline, change in IOP at 3 months was similar between both groups (P=0.15). Rates of additional medications and procedures did not differ between the 2 groups at any postoperative visit. Conclusions: Early intracameral injection of viscoelastic during Ahmed glaucoma valve implantation did not reduce early postoperative complication rates.