Incisional glaucoma surgery, or “filtering” surgery, refers to either trabeculectomy or a tube shunt procedure. Either type is done on an outpatient basis either at a hospital or surgery center facility. Both of these procedures can potentially lower your eye pressure a great deal and place your glaucoma under better control, reducing the risk for blindness.
A trabeculectomy involves making a “trap door” out of the wall of the eye, thus making a new drain in your eye, and allowing another place for fluid to drain from your eye, reducing the eye pressure. The result is a blister or a “bleb” on the surface of the eye, located under your upper eyelid.
A tube shunt is a device that is sewn onto the wall of the eye, with the tube entering the eye to “shunt” fluid from inside the eye to the plate on the surface of the eye. The plate is covered by your own tissue (conjunctiva) and, in most cases, is normally not visible.