Question: What is filtration surgery, when is it used to treat glaucoma, and what are the risks/benefits?
Answer: Filtration surgery generally refers to a procedure called trabeculectomy, or TRAB. In this procedure you're taken to the operating room and some of the tissue of the eye is removed to create a channel to allow fluid to drain more easily from the inside of the eye to the outside part of the eye. And this generally forms what we call a filtration blip, or blister, that sits on the top part of the eye. Now in general, this blister is not visible because it's covered by your upper lid.
This procedure is generally performed when the pressure is too high and it seems as though your disease is progressing or the glaucoma is progressing. In general, this procedure is performed after medication and laser options are either ineffective or are not viable options. There are some specific circumstances in which filtration surgery is performed initially or at the very beginning of glaucoma, but these are usually isolated circumstances. As with any filtration or incisional surgery, bleeding, infections, acceleration of cataract growth can become of the complications, and in some cases these complications can be very serious.
It's important to consider the risks and benefits when considering any surgical procedure, and you should thoroughly consult your treating ophthalmologist.