The effect of different doses of intracameral bevacizumab on surgical outcomes of trabeculectomy for neovascular glaucoma.

Purpose: To prospectively evaluate the effect of 1.25 mg and 2.5 mg intracameral bevacizumab on surgical outcomes of trabeculectomy for neovascular glaucoma (NVG), with primary outcome measures being the regression of neovascularization of iris (NVI) and reduction of intraocular pressure (IOP).
Methods: Consecutive patients with neovascular glaucoma from December 2006 to March 2007 were randomized into two cohorts assigned to receive 1.25 mg (Group 1) or 2.5 mg (Group 2) intracameral bevacizumab prior to undergoing mitomycin C (MMC) trabeculectomy. Surgical outcome measures were evaluated following initial injection and during follow-up post-surgery.
Results: The most common causes for iris neovascularization were central retinal vein occlusion (47.3%) and proliferative diabetic retinopathy (36.8%). Following intracameral bevacizumab, there was a reduction in IOP compared to baseline in both treatment groups (Group 1, n=9: -10.4+/-4.5 mmHg, p=0.57; Group 2, n=10: -12.1+/-5.5 mmHg, p=0.1). The reduction in IOP was not statistically significant between the two groups (p=0.55). None of the eyes underwent further retinal ablation post trabeculectomy. Reappearance of NVI was seen in three eyes (Group 1, n=2; Group 2, n=1) after 3 months. There was no statistically significant difference in regression of NVI grade between the treatment groups (p=0.1).
Conclusions: The efficacy of an intracameral dose of 2.5 mg of bevacizumab prior to trabeculectomy for eyes with NVG is not significantly different from a 1.25 mg dose. Intracameral bevacizumab followed by trabeculectomy results in good surgical outcomes. Longer follow-up would be needed to evaluate differences in recurrence rates of iris neovascularization using different dosages.