Surgical Procedures for Glaucoma

When it is not possible to lower the intraocular pressure adequately with eye drops or oral drugs, eye surgery may be advised. In some situations, you and your doctor may decide to try surgery instead of using drops, especially in the case of angle-closure glaucoma surgery.

Surgical procedures may include:

Laser Surgery

This is performed in a doctor's office or an eye clinic. In laser surgery, the surgeon uses a concentrated high-energy beam of light to make changes to the eye to help relieve the intraocular pressure.

The 3 most frequently performed procedures are:

Trabeculoplasty —This procedure is most often used to treat open-angle glaucoma. Using the laser, the surgeon will make many small microscopic burns in the drainage area of the eye. This will allow the aqueous fluid to drain more freely. The procedure takes 10-20 minutes and you can resume normal activities right after it. It takes about 2-3 weeks before you can see the maximum effect from the surgery. Most people will need to continue medications and repeat treatment may be needed in half of all people having this procedure.

Iridotomy —This surgery is frequently used to treat angle-closure glaucoma or to prevent it in those who have very narrow drainage angles. Using the laser, the surgeon will make a small hole in the iris. This will allow the aqueous fluid to flow more freely inside the eye and help to widen the drainage angle between the cornea and iris.

Cyclophotocoagulation —This procedure is usually reserved for more advanced or aggressive cases of glaucoma that are refractory to other treatments. Using either the laser or a freezing probe, the surgeon will destroy selected areas of the ciliary body—the part of the eye that produces fluid. This will reduce the production of aqueous fluid.

Description of the Procedure:

The surgeon will place eye drops into your eyes to numb them. You will sit facing the laser machine. Using a special lens held to the front of your eye, the surgeon will focus the high-energy beam of light at specific structures in your eye. You may see flashes of bright green or red light. The process often takes just a few minutes.

You cannot rub your eyes for at least 20 minutes or until the numbing eye drops have worn off. You may experience some local eye irritation. You may need someone to drive you home after the procedure, but most people can resume their normal activities within a day after the procedure. Your vision will probably be blurry for 1-2 days after the procedure.

Incisional Surgery

Trabeculectomy —Also known as filtering surgery, involves the use of tiny instruments to make a tiny hole in the sclera, or white of the eye where it meets the cornea. The aqueous humor can now drain out through the hole and be reabsorbed into the bloodstream. This reduces the pressure in the eye. In some cases, the surgeon may place a valve in the eye through a tiny incision. These valves act as a regulator for the buildup of fluid within the eye, allowing fluid to flow out and be reabsorbed.

Description of the Procedure:

Incisional surgery is usually performed in an operating room with local anesthesia. The surgeon will make the small incision in the eye to allow for a slow release of aqueous fluid. If necessary, the surgeon will place a tiny valve in the eye through an incision. The surgeon will also often cut out a small hole in the iris to help prevent the iris from blocking the hole.

Mechanical shunts —In advanced cases, sometimes placement of a mechanical shunt is the best option. Shunts are small silicone tubes that are inserted into an eye to help drain the aqueous fluid.

Microinvasive Surgery

The goal of microinvasive glaucoma surgery (MIGS) is to reduce pressure by increasing fluid outflow. MIGS procedures utilize stents, bypasses, and implants to make new channels in the eye. The channels move fluid out of the eye and into the bloodstream. Minimizing tissue damage speeds recovery time.


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Last reviewed March 2018 by EBSCO Medical Review Board Daniel A. Ostrovsky, MD
Last Updated: 10/5/2017

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