Tube-shunt surgery for glaucoma
Tube-shunt surgery (seton glaucoma surgery) involves placing a flexible plastic tube with an attached silicone drainage pouch in the eye to help drain fluid (aqueous humor) from the eye. This type of surgery is usually done after a trabeculectomy that failed. If a person already has or is likely to form scar tissue in the eye, this type of surgery may be done at the start.
Tube-shunt surgery can be done with the person asleep (general anesthesia) or with anesthesia applied only to the eye (local anesthesia).
What To Expect After Surgery
The person does not have to be admitted to the hospital. But children may stay in the hospital overnight following surgery. And in some cases, your doctor may recommend that you stay in the hospital overnight following surgery.
The person usually sees the doctor within a day after tube-shunt surgery and 2 to 5 other times during the 6 weeks after surgery, depending on the person's recovery.
Initially after surgery antibiotics may be applied to the eye. Antibiotics may also be injected under the lining of the eyelid (conjunctiva) at the time of the surgery. For the first night only, the eyelid is usually taped shut, and a hard covering (eye shield) is placed over the eye. Corticosteroid medicines are usually applied to the eye for about 1 to 2 months after surgery to decrease inflammation in the eye.
Physical activity that might jar the eye needs to be avoided after surgery. People usually need to avoid bending, lifting, or straining for several weeks after surgery.
After surgery, people who have problems with constipation may need to take laxatives to avoid straining while trying to pass stools. Straining can raise the pressure inside the eye. Your doctor may suggest wearing a shield at night to avoid rubbing the eye when you sleep.
Why It Is Done
Tube-shunt surgery is most often used for people who have had previous trabeculectomy surgery that was not successful, usually due to scarring.
Tube-shunt surgery is also frequently used to treat glaucoma when a person has a:
- Difficult case of glaucoma and the doctor thinks that other surgical methods may fail.
- Form of glaucoma in which new blood vessels grow on the colored part of the eye, or iris. This is called neovascular glaucoma and occurs primarily in people with diabetes or who have vascular diseases in the eye. It is difficult to control.
- Corneal transplant, which is a surgery to replace the clear surface on the front of the eye (cornea).
Complications of tube-shunt surgery that may develop right after surgery include:
- High pressure in the eye, causing the space in the front part of the eye (anterior chamber) to collapse (malignant glaucoma).
- Inflammation in the eye.
- Bleeding or blood in the eye (hyphema).
- Softening of the eyeball due to fluid loss (hypotony).
- Movement of the tube causing it to come in contact with the clear cover of the eye (cornea), the iris, or the lens. This can affect vision or proper function of the eye.
Late complications of tube-shunt surgery include:
- Scar tissue forming around the device. The chances of this complication can be reduced if medicines, such as steroids, are used.
- Softening of the eyeball due to fluid loss (hypotony), leading to clouding of the lens (cataract).
- Infection in the eye.
- Blood in the eye (hyphema).
- Eye muscle imbalance, resulting in double vision.
What To Think About
Although tube-shunt pouches are becoming popular, they are not often used as an initial treatment for glaucoma. The advantage of tube-shunt surgery for glaucoma is that there is less chance of severe scarring that can block the drainage opening. This can be an important consideration for people who have had prior surgery for glaucoma that did not work. But the complications from tube-shunt surgery can be serious as well.