Surgery is not always necessary to treat glaucoma. Medicines can often control the pressure in the eyes, preventing further vision loss and blindness. Medicine will usually be tried first before surgery is considered.

Doctors can use either a surgical cutting tool or a very focused beam of light, called a laser, to perform surgery for glaucoma. Laser surgery is usually tried first when glaucoma medicines do not lower the pressure in the eyes (intraocular pressure, or IOP). If laser surgery does not help, your doctor may try conventional surgery.

Surgery may be needed for:

• Sudden (acute) closed-angle glaucoma. Laser treatment can create an opening in the colored part of the eye (iris) that will let fluid drain from the eye. People who have had closed-angle glaucoma in one eye usually need to have laser treatment on the other eye to prevent the same condition from developing. Also, people who have narrow drainage angles may need laser treatment to prevent acute closed-angle glaucoma. If laser treatment is not successful, then conventional surgery, such as surgical iridectomy or trabeculectomy, would be needed.
• Open-angle glaucoma, if the pressure in the eyes stays high or if damage to the optic nerve continues despite medication. Laser treatment may be needed early on to treat open-angle glaucoma, especially in people who have very high intraocular pressure and severe glaucoma. You may have laser surgery before you try medicine. In some cases, early surgery in open-angle glaucoma may be more effective than eyedrops at reducing the pressure in the eyes and preventing blindness.
• Infants with congenital glaucoma. They may need surgery as soon as possible to prevent blindness.

The primary goal of surgery for glaucoma is to preserve eyesight by:

• Maintaining the health of the optic nerve.
• Reducing the pressure in the eyes by opening blocked drainage angles or creating a new opening that fluid (aqueous humor) can flow through to leave the eye.

In some cases surgery may be done to relieve pain caused by glaucoma.

Surgery Choices

There are three basic types of surgery for glaucoma in adults.

Surgery to increase drainage of fluid from the eye

This type of surgery involves making a trapdoor that allows fluid to drain from the eye. The surgeon can use either a laser or a surgical cutting tool to do this. In severe glaucoma, surgery also may involve putting in a filtering device (seton), usually made of plastic, that drains fluid away from the front part of the eye to a place where it can drain out of the eye. These procedures are used to treat open-angle glaucoma and long-term (chronic) closed-angle glaucoma.

• Trabeculectomy removes a piece of tissue to allow fluid to drain from the eye.
• Tube-shunt surgery (seton glaucoma surgery) places a tube in the eye to allow fluid to drain.
• Laser trabeculoplasty burns tissue to create an opening that allows fluid to drain from the eye.
• Laser sclerostomy removes a piece of the white part of the eye to allow fluid to drain.

Surgery to prevent closure of the drainage angle