Comparison between the efficacy and side effects of intravitreal versus anterior chamber Bevacizumab injection in neovascular glaucoma patients

Rationale. Neovascular glaucoma is the type of glaucoma most refractory to treatment. The most frequent causes are those associated with retinal hypoxia, which promotes the upregulation of the VEGF synthesis and produces fibrovascular membranes over the anterior chamber angle. Because the administration of anti VEGF products is still off label for neovascular glaucoma, there is not a single accepted way of treatment. There are differences between the site of administration (vitreal or anterior chamber or both at the same time), the dose or the setting of the procedure. Objective. The objective of our study was to asses the difference of efficacy and complications of bevacizumab injection for vitreal administration versus anterior chamber administration. Methods and results. Prospective study with 18 eyes from 18 patients with neovascular glaucoma associated with proliferative diabetic retinopathy or retinal vein occlusion. Group A (10 patients) received intravitreal injection with 0.05 ml Bevacizumab. Group B (8 patients) received anterior chamber injection with 0.03 ml Bevacizumab. There was a significant decrease of intraocular pressure (p<0.01 for group A, p<0.05 for group B) for both groups. Group A also had a statistically significant decrease of the macular edema (p<0.05). The side effects were reduced for both groups. Discussion. Our conclusion was that for the neovascular glaucoma, which associates significant macular edema, the intravitreal procedure should be performed, while for neovascular glaucoma patients without retinal edema, the anterior chamber procedure should be preferred because of reduced potential side effects.