What are the risks of trabeculectomy surgery?

As with all surgery, there are possible side effects. Inflammation inside the eye is common and treated with drops. Some patients notice the drainage bleb under the upper eyelid or slight drooping of the eyelid, which usually settles. Serious problems are rare: bleeding inside the eye (less than 1 in 1000) and infection inside the eye (less than 1 in 1000) can lead to loss of vision. After surgery the pressure may be too high or too low, needing drops, clinic treatment or further surgery. A trabeculectomy also makes the eye more prone to infection in the long term, so any new pain, redness or blurred vision should be reported immediately.