Anti-vascular endothelial growth factor for control of wound healing in glaucoma surgery

Full citation: Cheng JW, Cheng SW, Wei RL, Lu GC. Anti-vascular endothelial growth factor for control of wound healing in glaucoma surgery. Cochrane Database of Systematic Reviews 2016, Issue 1. Art. No.: CD009782. DOI: 10.1002/14651858.CD009782.pub2.

Review question
Anti-vascular endothelial growth factor (VEGF) agents versus control or mitomycin C (MMC) for the outcome of trabeculectomy.

Background
Glaucoma filtration surgery, an eye operation in which a drainage fistula is created in the wall of the eye to reduce intraocular pressure (IOP), is usually reserved for glaucoma patients whose IOP cannot be sufficiently managed by medical and/or laser intervention. Scarring during wound healing can lead to failure of the operation, therefore, drugs are used to modify wound healing. Anti-VEGF agents have been proposed to decrease scar formation. This review asks whether there is evidence that the use of anti-VEGF drugs reduces the risk of failure of glaucoma surgery. We searched the medical literature for studies that evaluated the benefit and harms of anti-VEGF subconjunctival injection during trabeculectomy for control of wound healing, compared to control or MMC.

Date of searches
The evidence is up to date to November 2015.

Key results
Five studies (conducted in India, Turkey, USA and two in Iran) with a total of 175 participants were included in this review. The effect of anti-VEGF agents on IOP control is uncertain.

We found one small study, comparing anti-VEGF with control, which did not provide data on the primary outcome: the proportion of complete successful trabeculectomies at 12 months after surgery.

Four trials compared anti-VEGF to MMC, and two trials reported one or more outcomes of IOP control (complete success, qualified success, or mean IOP) at 12 months. There was low quality evidence compatible with decreased chance of complete success for anti-VEGF agents, suggesting that for patients using MMC with an 81.0% rate of complete success, the complete success rate using anti-VEGF agents would be between 37.2% and 87.4%. There was moderate quality evidence suggesting that for patients using MMC with a 95.2% qualified success rate, the qualified success rate using anti-VEGF agents would be between 82.9% and 100.0%, with no difference between anti-VEGF and MMC. Additionally, there was low quality evidence compatible with higher mean IOP for anti-VEGF agents between 0.15 mm Hg and 3.57 mm Hg, compared to MMC, and the effect was still uncertain.

The conclusion of this review is that there is still uncertainty of the effect on IOP control of the subconjunctival use of anti-VEGF in patients undergoing trabeculectomy, compared to the use of MMC.

Quality of evidence
There is currently evidence of low quality which is insufficient to refute or support anti-VEGF subconjunctival injection in glaucoma surgery. Several trials are ongoing and will be included in updates of the review.