Glaucoma Surgery

Glaucoma Eye Chart

What is glaucoma?

Glaucoma is a group of eye diseases that can damage the optic nerve and cause permanent vision loss. Eye pressure can play an important role, but glaucoma can develop even when eye pressure is within the normal range. Because glaucoma often has no early symptoms, regular eye exams are important for finding it before significant vision loss occurs.

What is the optic nerve?

The optic nerve is made up of more than 1 million nerve fibers that carry visual information from the retina to the brain. The retina is the light-sensitive tissue at the back of the eye. A healthy optic nerve is essential for good vision.

What are some other forms of glaucoma?

Open-angle glaucoma is the most common form of glaucoma. It develops gradually and often has no noticeable symptoms in its early stages. Other forms include:

• Low-tension or normal-tension glaucoma. Optic nerve damage and narrowed side vision occur in people with normal eye pressure. Lowering eye pressure at least 30 percent through medicines slows the disease in some people. Glaucoma may worsen in others despite low pressures. A comprehensive medical history is important in identifying other potential risk factors, such as low blood pressure, that contribute to low-tension glaucoma. If no risk factors are identified, the treatment options for low-tension glaucoma are the same as for open-angle glaucoma.
• Angle-closure glaucoma. The drainage angle becomes blocked, causing eye pressure to rise. A sudden attack can cause severe eye pain, headache, nausea, blurred vision, redness, and halos around lights. This is a medical emergency and requires immediate treatment.

• Congenital glaucoma. Some children are born with or develop glaucoma because the eye's drainage system does not develop normally. Symptoms can include cloudy eyes, excessive tearing, and sensitivity to light. Treatment may include surgery and other therapies.
• Secondary glaucomas. These can develop as complications of other medical conditions. These types of glaucomas are sometimes associated with eye surgery or advanced cataracts, eye injuries, certain eye tumors, or uveitis (eye inflammation). Pigmentary glaucoma occurs when pigment from the iris flakes off and blocks the meshwork, slowing fluid drainage. A severe form, called neovascular glaucoma, is linked to diabetes. Corticosteroid drugs used to treat eye inflammations and other diseases can trigger glaucoma in some people. Treatment includes medicines, laser surgery, or conventional surgery.

How does open-angle glaucoma damage the optic nerve?

In the front of the eye is a space called the anterior chamber. A clear fluid flows continuously in and out of the chamber and nourishes nearby tissues. The fluid leaves the chamber at the open angle where the cornea and iris meet. (See diagram below.) When the fluid reaches the angle, it flows through a spongy meshwork, like a drain, and leaves the eye.

Sometimes, when the fluid reaches the angle, it passes too slowly through the meshwork drain. As the fluid builds up, the pressure inside the eye rises to a level that may damage the optic nerve. When the optic nerve is damaged from increased pressure, open-angle glaucoma–and vision loss–may result. That’s why controlling pressure inside the eye is important.

Who is at risk for glaucoma?

Anyone can develop glaucoma. Some people are at higher risk than others. They include:

• African Americans over age 40.
• Everyone over age 60, especially Mexican Americans.
• People with a family history of glaucoma.

A comprehensive dilated eye exam can reveal more risk factors, such as high eye pressure, the thinness of the cornea, and abnormal optic nerve anatomy. In some people with certain combinations of these high-risk factors, medicines in the form of eye drops reduce the risk of developing glaucoma by about half.

Medicare covers an annual comprehensive dilated eye exam for some people at high risk for glaucoma.

What can I do to protect my vision?

Early detection is one of the best ways to protect your vision from glaucoma. Regular comprehensive eye exams allow your eye doctor to check your eye pressure, optic nerve, visual field, and other signs of glaucoma.

If you have been diagnosed with glaucoma, follow your treatment plan and keep your scheduled appointments. Glaucoma can often be managed successfully, but vision already lost from glaucoma cannot be restored.

What are the symptoms of glaucoma?

Early glaucoma often has no symptoms. Many people do not notice a change in their vision until the disease has already progressed.

As glaucoma advances, peripheral or side vision may gradually become affected. Without treatment, vision loss can continue and eventually become severe.

Glaucoma can develop in one or both eyes.

How is glaucoma detected?

Glaucoma is diagnosed through a comprehensive eye examination. Depending on your individual risk factors, your doctor may perform:

• Visual acuity testing: Measures how clearly you see at different distances.
• Visual field testing: Checks your peripheral vision and looks for areas of vision loss.
• Dilated eye examination: Allows your doctor to examine the optic nerve and retina for signs of damage.
• Tonometry: Measures the pressure inside the eye.
• Pachymetry: Measures the thickness of the cornea, which can help your doctor better understand your eye pressure and glaucoma risk.

Can glaucoma be treated?

Yes. While glaucoma cannot currently be cured, treatment can help slow or prevent further vision loss. The goal of treatment is usually to lower eye pressure to a level that is safe for your particular eyes.

Treatment may include prescription eye drops, laser treatment, or surgery. The right approach depends on the type and severity of glaucoma, your eye pressure, and other individual factors.

• Medicines: Prescription eye drops are commonly used to lower eye pressure by reducing fluid production or helping fluid drain more effectively. Your doctor may recommend one or more medications depending on your needs.
• Before you begin glaucoma treatment, tell your eye care professional about other medicines you may be taking. Sometimes the drops can interfere with the way other medicines work.
• Glaucoma medicines may be taken several times a day. Most people have no problems. However, some medicines can cause headaches or other side effects. For example, drops may cause stinging, burning, and redness in the eyes. Many drugs are available to treat glaucoma. If you have problems with one medicine, tell your eye care professional. Treatment with a different dose or a new drug may be possible.
• Because glaucoma often has no symptoms, people may be tempted to stop taking or may forget to take, their medicine. You need to use the drops or pills as long as they help control your eye pressure. Regular use is very important. Make sure your eye care professional shows you how to put the drops into your eye. See tips “How should I use my glaucoma eye drops?” on using your glaucoma eye drops.
• Laser trabeculoplasty: Treatments such as selective laser trabeculoplasty (SLT) help improve fluid drainage through the eye's natural drainage system. SLT may be used as an initial treatment or along with medication in appropriate patients.
• Laser trabeculoplasty is performed in your doctor’s office or eye clinic. Before the surgery, numbing drops will be applied to your eye. As you sit facing the laser machine, your doctor will hold a special lens to your eye. A high-intensity beam of light is aimed at the lens and reflected onto the meshwork inside your eye. You may see flashes of bright green or red light. The laser makes several evenly spaced burns that stretch the drainage holes in the meshwork. This allows the fluid to drain better.
• Like any surgery, laser surgery can cause side effects, such as inflammation. Your doctor may give you some drops to take home for any soreness or inflammation inside the eye. You need to make several follow-up visits to have your eye pressure monitored.
• If you have glaucoma in both eyes, only one eye will be treated at a time. Laser treatments for each eye will be scheduled several days to several weeks apart.
• Studies show that laser surgery is very good at reducing pressure in some patients. However, its effects can wear off over time. Your doctor may suggest further treatment.
• Laser Endocyclophotocoagulation (ECP). ECP is a laser surgery done with or without cataract surgery to lower intraocular pressure. Laser is done inside the eye on the ciliary processes to reduce aqueous production. This treatment can reduce the number of medications used or reduce intraocular pressure (IOP) in some patients. If you are considering cataract surgery ask your surgeon if ECP is a good option for you.
• Conventional surgery. Conventional surgery makes a new opening for the fluid to leave the eye. (See diagram.) Your doctor may suggest this treatment at any time. Conventional surgery often is done after medicines and laser surgeries have failed to control pressure.
• Conventional surgery is performed in an eye clinic or hospital. Before the surgery, you will be given medicine to help you relax. Your doctor will make small injections around the eye to numb it. A small piece of tissue is removed to create a new channel for the fluid to drain from the eye. For several weeks after the surgery, you must put drops in the eye to fight infection and inflammation. These drops will be different from those you may have been using before surgery.

As with laser surgery, conventional surgery is performed on one eye at a time. Usually, the operations are four to six weeks apart. Conventional surgery is about 60 to 80 percent effective at lowering eye pressure. If the new drainage opening narrows, a second operation may be needed. Conventional surgery works best if you have not had previous eye surgery, such as a cataract operation.

In some instances, your vision may not be as good as it was before conventional surgery. Conventional surgery can cause side effects, including cataracts, problems with the cornea, and inflammation or infection inside the eye. The buildup of fluid in the back of the eye may cause some patients to see shadows in their vision. If you have any of these problems, tell your doctor so a treatment plan can be developed.

Conventional surgery makes a new opening for the fluid to leave the eye.

How should I use my glaucoma eye drops?

If your doctor prescribes glaucoma eye drops, use them exactly as directed. Consistent treatment is important for keeping eye pressure under control and protecting your vision.