A trabeculectomy, also sometimes called glaucoma filtration surgery, is a surgical procedure used to treat glaucoma. Glaucoma is a group of conditions in which there is too much pressure in the eye, called intraocular pressure. This condition can gradually lead to vision loss. A trabeculectomy helps manage glaucoma by allowing aqueous humor, which is the fluid in the eye, to drain more effectively. By reducing the amount of fluid, the intraocular pressure is decreased.
Not all glaucoma patients are ideal candidates for a trabeculectomy. It is best used for those who have specific types of the condition, called narrow-angle and open-angle glaucoma, as opposed to neovascular secondary or congenital glaucoma. The eye surgeon may recommend this procedure to people who have already tried lowering their intraocular pressure, and did not attain sufficient relief. A trabeculectomy tends to be more effective for patients who do not have diabetes and for those who have not previously had eye surgery.
Patients undergoing a trabeculectomy should expect the procedure to last about an hour. It is performed on an outpatient procedure, so staying overnight in a hospital is not required. The eye surgeon will first administer a local anesthetic to numb the eye. Patients who are nervous about the procedure may request a sedative, as well. An eyelid holder will be used to keep the patient from blinking.
With very small instruments, the eye surgeon will then make an incision in the sclera, or the white part of the eye. He will remove a tiny portion of tissue to make a reservoir for the aqueous humor. This reservoir, which is called a filtration bleb, collects the fluid so that it can then absorbed by the blood vessels and drain out of the eye. Tiny sutures are then used to close the incision and to cover it with the conjunctiva, or the outer layer of the eye.
Following the trabeculectomy, the eye surgeon will inject antibiotics to the area around the eye. The eye will be covered with a dressing and an eye shield. Patients should expect to keep the shield over their eyes for the rest of the day, as well as the night after the procedure. Typically, the surgeon will instruct them to wear the shield every night for a month. Patients should also avoid strenuous activities for the first few weeks, as straining may increase intraocular pressure and may elevate the possibility of damage to the area.
Before undergoing a trabeculectomy, patients should understand the potential risks involved. It is fairly typical for people to notice blurred vision for the first few weeks, as well as mild discomfort. Scarring can also occur, however the surgeon can use corticosteroids immediately after surgery to decrease this problem. Other risks can include bleeding in the eye, infection, and sudden loss of central vision, which is permanent. Patients who notice any abnormalities with their eyes or vision should contact the eye surgeon immediately.