Glaucoma

Glaucoma is an eye disease that causes loss of sight by damaging a part of the eye called the optic nerve. This nerve sends information from your eyes to your brain. When glaucoma damages your optic nerve, you begin to lose patches of vision, usually side vision (peripheral vision). Over time, glaucoma may also damage straight ahead (central) vision. You may not notice a loss of side vision until you have lost a great deal of your sight. When checking for glaucoma, eye doctors usually look for damage to the optic nerve and any loss of side vision. They may also check your eye pressure.

Glaucoma is often called "the sneak thief of sight." That’s because people usually do not notice any signs of the disease until they have already lost significant vision. Once lost, vision can't be restored. More than 2.2 million Americans age 40 and older have open angle glaucoma, the most common form of glaucoma. At least half don't even know they have it.

font color="#c2905f">What are the Different Types of Glaucoma?
There are many types of glaucoma. Often, the cause of high pressure in the eye can help tell the type of glaucoma and the best treatment for it. The most common types include:

Chronic (Open Angle) Glaucoma
This is the most common type. In open angle glaucoma, aqueous fluid drains too slowly and pressure inside the eye builds up. It usually results from aging of the drainage channel, which doesn't work as well over time. However, younger people can also get this type of glaucoma.

Normal Tension Glaucoma
This is a form of open angle glaucoma not related to high pressure. People with normal tension glaucoma may be unusually sensitive to normal levels of pressure. Reduced blood supply to the optic nerve may also play a role in normal tension glaucoma.

Acute (Angle Closure) Glaucoma
Less than 10 percent of Caucasians or African-Americans have this form, but for those of Asian and Native American descent, the risks are as high as for open angle glaucoma. Hispanics are midway between these groups. It causes a sudden rise in pressure, requiring immediate, emergency medical care. The signs are usually serious and may include blurred vision, severe headaches, eye pain, nausea, vomiting or seeing rainbow-like halos around lights. Occasionally, the condition may be without symptoms; similar to open angle.

Secondary Glaucoma
Another 10 percent of glaucoma cases come from certain diseases and conditions that damage the eye's drainage system. These include diabetes, leukemia, sickle-cell anemia, some forms of arthritis, cataracts, eye injuries or inflammation of the eye, steroid drug use and growth of unhealthy blood vessels. For information about uveitis, a kind of inflammation that can cause glaucoma, visit our Uveitis Learning Center.

Post-Surgical Glaucoma
Some surgeries, such as retinal reattachments, increase the chance of getting glaucoma.

How Do Eye Doctors Treat Glaucoma?

Glaucoma can usually be treated and controlled using medicine(s), laser surgery, glaucoma surgery or a combination of these treatments. Medicines (eye drops) are typically the first step in treatment, but laser surgery may be just as effective as a first choice. Your treatment is up to you and your doctor. In this section, you will learn about your options for treatment.

Eye doctors use many medicines to treat glaucoma. These drugs lower pressure inside the eye. Often, people with glaucoma must take these medicines for life to control the pressure and limit vision loss.

Glaucoma medicines are usually in the form of drops, but also come in pills or ointment. They work to lower the amount of aqueous fluid produced and/or improve fluid drainage in the eye.

Doctors are researching new drugs that can protect or strengthen the optic nerve. Some medicines already available may help stabilize the optic nerve as well as lower pressure inside the eye.

All glaucoma medicines may cause side effects, some of which can be uncomfortable. A few side effects can be quite serious, but those side effects are not common.

The glaucoma medicines listed below are grouped by the way they work. Some of the possible side effects are also listed. Not every drug in a category will have all the possible side effects listed. Your doctor can tell you which side effects are possible with the medicines you use.

Remember, you and your doctor must work together to determine the best medicines for you.

Types of Medicines

Prostaglandin Analogues are drugs that lower pressure in the eye by improving fluid drainage. They have the advantage of requiring use only once per day.

Possible side effects. A rare side effect may be a darkening of eye color. Often, there is an increased growth of eyelashes. Side effects can also include redness, itching, burning and blurred vision.

Prostaglandin Analogues

Medicine Brand Name
latanoprost Xalatan®
travoprost Travatan®
bimatoprost Lumigan®
unoprostone Rescula®

Beta-blockers decrease pressure inside the eye by reducing the amount of aqueous fluid your eye makes. These medicines are available as eye drops.

Possible side effects include possible respiratory problems, lowered heart rate and blood pressure, blurred vision, tiredness, forgetfulness, and changes in blood cholesterol levels. People with asthma, some kinds of heart disease or low blood pressure should be very careful about using beta-blockers to treat their glaucoma. Also, if a patient is on other "blocker" medicines for other health problems, the combined effect of the drugs could cause problems.

This is why it's important to tell all of your doctors about all the medicines you are taking.

Beta Blockers

Medicine Brand Name
betaxolol Betoptic®, Betoptic® S
carteolol Ocupress®
levobunolol Betagan®
metipranolol OptiPranolol®
timolol hemihydrate Betimol®
timolol maleate Timoptic®,Timoptic-XE®,Cosopt® (see also anhydrase inhibitors)

This is why it's important to tell all of your doctors about all the medicines you are taking.

Alpha-adrenergic agonists are eye drops that lessen the amount of aqueous fluid the eye makes and may also increase flow of fluid out of the eye. These drops are sometimes used after laser surgery (see page 18) to prevent sudden rises in pressure.

Possible side effects include allergic reactions, dry mouth, burning of the eyes, dilated pupils, nasal decongestion,
and drowsiness.

Alpha-Adrenergic Agonists

Medicine Brand Name
apraclonidine Iopidine®
brimonidine tartrate Alphagan®, Alphagan-P®

Carbonic anhydrase inhibitors come in pills or drops. They reduce the amount of aqueous fluid the eye makes. Often, they are used when other drugs have not worked fully.

Possible side effects. The more common eye drop form of this drug may cause stinging, burning, a feeling of something in the eye, and an odd taste in the mouth. Taken as pills (only rarely nowadays), these drugs can have side effects throughout the body, including fatigue, tingling in the hands and feet, depression, frequent urination, anemia, kidney stones, loss of appetite, weight loss, diarrhea, and stomach cramps. Monitoring the dose of the oral pill and taking the medicine with food may help. Pregnant women and people sensitive to sulfa-related drugs should not take these medicines. A toxic reaction may occur if taken with large doses of aspirin. Very rarely, these drugs can lead to serious conditions known as Stevens-Johnson syndrome and aplastic anemia.

Carbonic Anhydrase Inhibitors

Medicine Brand Name
acetazolamide Diamox®
methazolamide Neptazane®
dichlorphenamide Daranide®
brinzolamide hydrochloride Azopt®
dorzolamide hydrochloride Trusopt®, Cosopt® (see beta blockers)

Miotics lower pressure by tightening tiny muscles inside the eye. This helps to open up the eye's drainage system, making it easier for aqueous fluid to flow out of the eye. Miotics come in eye drops or gels. When used as drops, these drugs usually need to be used several times a day, increasing the chance of forgetting a dose. Miotics are not commonly used any more except in certain cases.

Possible side effects include decreased pupil size, blurred vision, poor night vision, nearsightedness, watering eyes, brow and eye aches, and allergic reactions.

Miotics

Medicine Brand Name
carbachol Isopto® Carbachol
pilocarpine Isopto® Carpine, Pilocar®, Pilopine®, Pilagan®

Other Medicines

Anticholinesterase Iodide

Medicine Brand Name
echothiophate iodide Phospholine® Iodide

Combinations containing two medicines in the same bottle

Cosopt® = Timoptic® and Trusopt®

Xalacom® = Xalatan® and timolol

E-pilo® = Epinephrine® and pilocarpine

Follow your treatment plan!

It's up to you to follow your treatment plan and have regular follow-up visits. At follow-up visits, your doctor will check to see if your glaucoma is getting worse. Remember to report anything you believe may be a side effect of the medicine you are taking.

Don't Skip Doses!

Take your medicine as scheduled. Skipping doses of your medicine may put your vision in danger and mislead your doctor. Be sure to tell your doctor if you've missed any doses.

With a chronic disease like glaucoma, it can be hard to remember to use medicines as directed. It may help to link taking medicine to the things you do every day like eating meals or brushing your teeth.

After evaluating your progress, your doctor may try changing your doses, switching medicines or changing other parts of your treatment to find the best results for you. Sometimes simple changes like adjusting your schedule to take your medicines at mealtimes or before bed can make your drug routine more comfortable.

Glaucoma Laser Surgery

Some people may need eye surgery to control their glaucoma. Lasers are very useful for treating glaucoma because they avoid cutting and have a lower chance of complications (compared to glaucoma surgery).

There are three common laser procedures:

Laser trabeculoplasty
Peripheral iridotomy
Laser cyclophotocoagulation

Laser trabeculoplasty or selective laser trabeculoplasty improves the outflow of aqueous fluid. A laser is used to make from 50 to 100 tiny burns in the trabecular meshwork. The procedure opens up the mesh-like outflow pathway to improve draining of fluids from the eye. Sometimes your doctor may perform this procedure over two visits. The benefit of the treatment may last for several years, but it is not a cure. Half the people who have this surgery need additional treatment within two years. Laser trabeculoplasty may be used to treat patients who had a good first effect with laser treatment, but over time have lost some of the pressure-lowering response.

A peripheral iridotomy is most often used to treat narrow angle or angle closure glaucoma. The laser beam creates a tiny hole in the colored part of the eye (the iris). This lets the pressure in front of the iris become the same as the pressure behind the iris. As a result, the iris moves away from the drainage angle and the aqueous fluid can resume
draining normally.

Laser cyclophotocoagulation is used for severe cases of glaucoma. It eliminates tiny areas of the ciliary body that make aqueous fluid. This "turns down the faucet."

People usually don't feel any pain with these procedures, although some report a slight stinging. (Laser cyclophotocoagulation requires a numbing block to
the eye to prevent pain with the procedure.) Most
patients take it easy the day of their treatment, but go
back to their normal routine the following day.

Many people need to keep taking medicines even after
laser surgery.

Laser surgery is usually successful, but there are some risks. These include a temporary, generally short-term increase in eye pressure, temporary inflammation of the eye, and possibly a slightly increased risk of developing cataracts.

Glaucoma Surgery

If medicine or laser surgery does not relieve eye pressure, a patient may need glaucoma surgery. There are several options.

Filtering surgery
Draingage implant surgery

Filtering surgery creates a new path through the eye's tissues to let fluid drain from the eye.

In the most common filtering surgery, called a trabeculectomy or a sclerostomy, the surgeon makes a small opening in the white part of the eye (the sclera) to create a new outflow path. The fluid then flows through the new opening and creates a bleb, which is like a small bubble or reservoir on the surface of the eye. The bleb holds the fluid while it is slowly absorbed into the surrounding tissue. The upper eyelid usually hides the bleb, so it's not noticeable to you or others.

Most people who have this procedure no longer need medicine after surgery. Some people treated still need medicine, but they have better pressure control after the surgery. About 15 percent do not benefit from filtering surgery.

An alternative type of glaucoma surgery may occasionally be performed in which the tissues over the drainage area are thinned but not fully penetrated. This procedure may produce fewer complicatons than trabeculectomy, but also may be less effective in achieving low intraocular pressures.

Drainage implant surgery is sometimes performed when a person is not suited for filtering surgery or when earlier filtering surgery has failed. Depending on the kind of implant used, the surgery is called valve, shunt or seton surgery.

In these procedures, the surgeon inserts a tiny tube through the sclera into the front part of the eye behind the iris. This tube becomes a path for fluid to drain away. The other end of the tube is attached to a tiny reservoir that acts like the bleb (described on page 19) to hold fluid until it is absorbed into the surrounding tissue. The reservoir is placed on the surface of the eye, back between the eye muscles, so it is not visible.

Right after filtering or drainage implant surgery, a person may have a temporary decrease of vision. Vision usually improves over several weeks to its previous level. It also takes time to recuperate from either form of surgery. For example, in the weeks after surgery, people often must avoid getting water into their eyes, reading, bending, lifting heavy objects and driving.

Risks of glaucoma surgery

Glaucoma surgeries have some possible risks, such as:

* A higher chance of getting cataracts
* Infection or leaking of the incision
* Adverse reactions to anesthesia

Unfortunately, the new drainage path can close, causing pressure in the eye to rise again. Filtering surgery can be repeated with good results. Also, drainage implants are often successful in patients whose filtering surgery has failed. The medicines that reduce inflammation and control scar formation after surgery have helped increase the success of glaucoma surgeries.