What is glaucoma?
How does increased pressure damage your eye?
What are the symptoms of glaucoma?
Who gets glaucoma?
How do I know if I have glaucoma?
How often should I have an eye exam?
What is the treatment for glaucoma?
What are the different types of glaucoma?
What are the symptoms of glaucoma?
How is glaucoma diagnosed?
What are the risk factors for glaucoma?
What is a risk factor?
Are there different types of Glaucoma?
How is Glaucoma detected?
Is surgery necessary to treat Glaucoma?
Can Glaucoma cause blindness if left untreated?
What are the signs and symptoms?
Can Glaucoma be cured?
Can Glaucoma be prevented?
How can I know if I am a high risk for Glaucoma?
What is the best defense against Glaucoma?
What are the risk factors for glaucoma?
What are the different kinds of glaucoma?
What causes glaucoma?
How common is glaucoma?
Does eye pressure vary day to day?
Laser treatment for glaucoma
Does it matter if I miss my glaucoma drops?
What is glaucoma?
Glaucoma is an eye disease that may cause loss of vision. It occurs as a result of a buildup of fluid in the eyeball. Normally, this fluid nourishes your eye and keeps it healthy. After the fluid circulates, it empties through a drain in the front of your eye. In people who have glaucoma, the drain in the eye is blocked and the fluid can't run out of the eyeball. Instead, the fluid builds up and causes increased pressure in the eye.
Glaucoma is the term for a diverse group of eye diseases, all of which involve progressive damage to the optic nerve. Glaucoma is usually, but not always, accompanied by high intraocular (internal) fluid pressure. Optic nerve damage produces certain characteristic defects in the individual’s peripheral (side) vision, or visual field.
How does increased pressure damage your eye?
The increased pressure destroys the nerve cells in the eye, which leads to vision loss. At first, you may have blind spots only in your peripheral (side) vision. If your glaucoma isn't treated, your central vision will also be affected. Vision loss caused by glaucoma is permanent.
What are the symptoms of glaucoma?
The main symptom of glaucoma is vision loss, especially loss of peripheral vision. However, half of all people who experience loss of vision caused by glaucoma are not aware they have the disease. By the time they notice loss of vision, the eye damage is severe.
Rarely, an individual will have an acute (sudden or short-term) attack of glaucoma. In these cases, the eye becomes red and extremely painful. Nausea, vomiting and blurred vision may also occur.
Who gets glaucoma?
Risk factors for glaucoma include:
* Being 60 years of age or older
* Belong to certain ethnic groups, including black and Latino
* A family history of glaucoma
* High pressure in the eyes
* Diabetes
* Hypertension
* Heart disease
* Near-sightedness (it is difficult for you to see objects in the distance)
How do I know if I have glaucoma?
You won't know you have glaucoma until you notice vision loss. Since glaucoma causes no symptoms other than vision loss, it is important that you have a complete eye exam by an ophthalmologist regularly. An ophthalmologist is a doctor who is trained to provide care for the eyes, including the diagnosis and treatment of glaucoma. Your ophthalmologist can measure your eye pressure, examine your optic nerve and evaluate your central and peripheral vision. Early diagnosis and treatment of glaucoma can prevent damage to the eye's nerve cells and prevent severe vision loss.
How often should I have an eye exam?
People 18 to 60 years of age should have an eye exam every 2 years. After age 60, you should have an eye exam once a year.
What is the treatment for glaucoma?
The purpose of treatment is to lower the pressure in the eye to prevent further nerve damage and vision loss. Glaucoma is usually treated first with medicated eyedrops. Medicines that can be taken orally (in pill form) can also be prescribed if eyedrops alone don't help relieve pressure.
If these treatments don’t work, your doctor may suggest surgery to relieve the pressure in your eyes.
What are the different types of glaucoma?
* open-angle glaucoma
With this most common type of glaucoma, the fluid that normally flows through the pupil into the anterior chamber of the eye cannot get through the filtration area to the drainage canals, causing a build-up of pressure in the eye. Nearly 3 million Americans - half of whom do not know they have the disease - are affected by glaucoma each year.
* low-tension or normal-tension glaucoma
While normal intraocular pressure ranges between 12 to 21 mm Hg, an individual may have glaucoma even if the pressure is within this range. This type of glaucoma presents optic nerve damage and narrowed side vision.
* angle-closure glaucoma
In angle-closure glaucoma, the fluid at the front of the eye cannot reach the angle and leave the eye because the angle becomes blocked by part of the iris. This results in a sudden increase in pressure and is generally a medical emergency, requiring immediate treatment to improve the flow of fluid.
* childhood glaucoma
Childhood glaucoma is a rare form of glaucoma that often develops in infancy, early childhood, or adolescence. Prompt medical treatment is important in preventing blindness.
* congenital glaucoma
Congenital glaucoma, a type of childhood glaucoma, occurs in children born with defects in the angle of the eye that slow the normal drainage of fluid. Prompt medical treatment is important in preventing blindness.
* primary glaucoma
Both open-angle and angle-closure glaucoma can be classified as primary or secondary. Primary glaucoma cannot be contributed to any known cause or risk factor.
* secondary glaucoma
Both open-angle and angle-closure glaucoma can be classified as primary or secondary. Secondary glaucoma develops as a complication of another medical condition or injury. In rare cases, secondary glaucoma is a complication following another type of eye surgery.
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What are the symptoms of glaucoma?
Most people who have glaucoma do not notice any symptoms until they begin to lose some vision. As optic nerve fibers are damaged by glaucoma, small blind spots may begin to develop, usually in the side or peripheral vision. Many people do not notice the blind spots until significant optic nerve damage has already occurred. If the entire nerve is destroyed, blindness results.
One type of glaucoma, acute angle-closure glaucoma, does produce noticeable symptoms because there is a rapid build-up of pressure in the eye. The following are the most common symptoms of this type of glaucoma. However, each individual may experience symptoms differently. Symptoms may include:
* blurred or narrowed field of vision
* severe pain in the eye(s)
* haloes (which may appear as rainbows) around lights
* nausea
* vomiting
* headache
The symptoms of acute angle-closure glaucoma may resemble other eye conditions. Consult a physician for diagnosis immediately if you notice symptoms, as this type of glaucoma is considered a medical emergency requiring prompt medical attention to prevent blindness.
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How is glaucoma diagnosed?
In addition to a complete medical history and eye examination, your eye care professional may perform the following tests to diagnose glaucoma:
* visual acuity test - the common eye chart test (see above), which measures vision ability at various distances.
* pupil dilation - the pupil is widened with eye drops to allow a close-up examination of the eye's retina.
* visual field - a test to measure a person's side (peripheral) vision. Lost peripheral vision may be an indication of glaucoma.
* tonometry - a standard test to determine the fluid pressure inside the eye.
What are the risk factors for glaucoma?
Although anyone can develop glaucoma, some people are at higher risk than others. The following are suggested as risk factors for glaucoma:
* race
Glaucoma is the leading cause of blindness for African Americans.
* age
Persons over age 60 are more at risk for developing glaucoma.
* family history
People with a family history of glaucoma are more likely to develop the disease.
* high intraocular pressure
Persons with an elevated (greater than 21 mm Hg) intraocular pressure (IOP) are at an increased risk.
The National Eye Institute, part of the National Institutes of Health, recommends that anyone in these risk groups receive an eye examination with dilated pupils every two years.
What is a risk factor?
A risk factor is anything that may increase a person's chance of developing a disease. It may be an activity, such as smoking, diet, family history, or many other things. Different diseases, including cancers, have different risk factors.
Although these factors can increase a person's risk, they do not necessarily cause the disease. Some people with one or more risk factors never develop the disease, while others develop disease and have no known risk factors.
But, knowing your risk factors to any disease can help to guide you into the appropriate actions, including changing behaviors and being clinically monitored for the disease.
Are there different types of Glaucoma?
There are three basic types: Primary, Secondary, and Congenital Glaucoma.
Primary Glaucoma is the most common type and can be divided into open angle and closed angle Glaucoma.
Open angle Glaucoma is the type seen most frequently in the United States. It is usually detected in its early stages during routine eye examinations.
Closed angle Glaucoma, also called acute Glaucoma, usually has a sudden onset. It is characterized by eye pain and blurred vision.
Secondary Glaucoma occurs as a complication of a variety of other conditions, such as injury, inflammation, vascular disease and diabetes.
Congenital Glaucoma is due to a developmental defect in the eye’s drainage mechanism.
How is Glaucoma detected?
Early detection of open angle Glaucoma is extremely important, because there are no early symptoms. Fortunately, routine eye exams are a major factor in early detection. People with a family history of Glaucoma should be checked at intervals in their 30s to establish a baseline. Initially, detection is based often on intraocular pressure readings, but also includes observation of the optic nerve as well as evaluation of optic nerve function using visual field tests.
Is surgery necessary to treat Glaucoma?
When medication and laser surgery fail to control progression of Glaucoma, a surgical procedure known as a filtering operation is recommended to create an artificial outlet for fluid from the eye, thus lowering intraocular pressure. Requiring use of an operating microscope and a local anesthetic, this procedure is performed in the hospital. If such a procedure is not feasible or has failed, production of aqueous fluid may be reduced by freezing (cryoprobe) or laser energy directly applied to the eyeball over the area where the fluid is produced.
The most helpful advice concerning Glaucoma is to keep in mind the importance of early detection through routine eye examination, faithful use of prescribed medications, and close monitoring by an eye doctor of the optic nerve, visual fields and pressures.
Can Glaucoma cause blindness if left untreated?
Between 89,000 and 120,000 people are blind from Glaucoma yearly. It is a leading cause of blindness, accounting for between nine and 12 percent of all cases of blindness. The rate of blindness from Glaucoma is between 93 and 126 per 100,000 population over 40.
Between two million and three million Americans age 40 and over, or about one in every 30 people in that age group have Glaucoma. This includes at least one half of all those who have Glaucoma are unaware of it.
What are the signs and symptoms?
In the vast majority of cases, especially in early stages, there are few signs or symptoms. In the later stages of the disease, symptoms can occur that include:
loss of side vision;
an inability to adjust the eye to darkened rooms;
difficulty focusing on close work;
rainbow colored rings or halos around lights; and
frequent need to change eyeglass prescriptions
Can Glaucoma be cured?
Not yet. Any sight that has been destroyed cannot be restored, but medical and surgical treatment can help stop the disease from progressing.
Can Glaucoma be prevented?
Not yet, but blindness from Glaucoma can be prevented through early detection and appropriate treatment.
How can I know if I am a high risk for Glaucoma?
A number of risk factors for the development of Glaucoma exist. The most important of these include high pressure inside the eye, advanced age, extreme near-sightedness, or a family history of Glaucoma.
What is the best defense against Glaucoma?
Glaucoma evaluation and treatment
What Is Glaucoma?
What Causes Glaucoma?
Who Gets Glaucoma?
When Should People Have Their Eyes Checked For Glaucoma?
How Do I Know If I Actually Have Glaucoma?
The Most Common Type Of Glaucoma
How Is Glaucoma Treated?
Surgical Procedures For Glaucoma
Medications You Need To Avoid
Do People With Glaucoma Have To Change The Way They Live?
Less Common Types Of Glaucoma And Their Treatments
Glaucoma In Children
What Does The Future Hold For Glaucoma Research And Treatment?
WHAT TESTS ARE USED FOR DIAGNOSIS OF GLAUCOMA?
Glaucoma is detected through a comprehensive eye exam that includes
Below are some basic questions to ask your doctor. If any additional questions occur to you during your visit, don't hesitate to ask.
* Do I have signs of glaucoma?
* What tests do I need to confirm a diagnosis?
* What treatment approach do you recommend?
* Do I need to follow any activity restrictions?
* What other self-care measures should I be taking?
* What is the long-term outlook in my case?
* How often should I be seen for follow-up care?
* Should I see a specialist?
* I have these other health conditions. How can I best manage them together?
What to expect from your doctor
A doctor who sees you for possible glaucoma is likely to ask you a number of questions, including:
* Have you had any eye discomfort or vision problems?
* Do you have any other signs or symptoms that concern you?
* Do you have any family history of eye problems, including glaucoma?
* What eye screening tests have you had, and when?
* Have you been diagnosed with any other medical conditions?
* What medications are you currently taking, including vitamins and supplements?
What is Glaucoma?
Glaucoma is the second leading cause of blindness.
Early diagnosis and treatment can minimize or prevent optic nerve damage and limit glaucoma-related vision loss. It's important to get your eyes examined regularly, and make sure your eye doctor measures your intraocular pressure.
What are the risk factors for glaucoma?
What are the different kinds of glaucoma?
What causes glaucoma?
How common is glaucoma?
Does eye pressure vary day to day?
Laser treatment for glaucoma
Does it matter if I miss my glaucoma drops?
Because chronic forms of glaucoma can destroy vision before any signs or symptoms are apparent, be aware of these factors:
* Elevated internal eye pressure (intraocular pressure). If your intraocular pressure is higher than normal, you're at increased risk of developing glaucoma, though not everyone with elevated intraocular pressure develops the disease.
* Age. Everyone older than 60 is at increased risk of glaucoma. For certain population groups such as African-Americans, however, the risk is much higher and occurs at a younger age than that of the average population. If you're African-American, ask your doctor when you should start having regular comprehensive eye exams.
* Ethnic background. African-Americans are five times more likely to get glaucoma than are Caucasians, and they're much more likely to experience permanent blindness as a result. Mexican-Americans and Asian-Americans also face an increased risk.
* Family history of glaucoma. If you have a family history of glaucoma, you have a much greater risk of developing it. Glaucoma may have a genetic link, meaning there's a defect in one or more genes that may cause certain individuals to be unusually susceptible to the disease. A form of juvenile open-angle glaucoma has been clearly linked to genetic abnormalities.
* Medical conditions. Diabetes and hypothyroidism increase your risk of developing glaucoma.
* Other eye conditions. Severe eye injuries can result in increased eye pressure. Injury can also dislocate the lens, closing the drainage angle. Other risk factors include retinal detachment, eye tumors and eye inflammations, such as chronic uveitis and iritis. Certain types of eye surgery also may trigger secondary glaucoma.
* Nearsightedness. Being nearsighted, which generally means that objects in the distance look fuzzy without glasses or contacts, increases the risk of developing glaucoma.
* Prolonged corticosteroid use. Using corticosteroids for prolonged periods of time appears to put you at risk of getting secondary glaucoma. This is especially true if you use corticosteroids eyedrops.
Symptoms
The most common types of glaucoma — primary open-angle glaucoma and acute angle-closure glaucoma — have completely different symptoms.
Primary open-angle glaucoma signs and symptoms include:
* Gradual loss of peripheral vision, usually in both eyes
* Tunnel vision in the advanced stages
Acute angle-closure glaucoma signs and symptoms include:
* Severe eye pain
* Nausea and vomiting (accompanying the severe eye pain)
* Sudden onset of visual disturbance, often in low light
* Blurred vision
* Halos around lights
* Reddening of the eye
Both open-angle and angle-closure glaucoma can be primary or secondary conditions. They're called primary when the cause is unknown and secondary when the condition can be traced to a known cause, such as eye injury, inflammation, tumor, advanced cataract or diabetes. In secondary glaucoma, the signs and symptoms can include those of the primary condition as well as typical glaucoma symptoms.
When to see a doctor
Don't wait for noticeable eye problems. Primary open-angle glaucoma gives few warning signs or symptoms until permanent damage has already occurred. Regular eye exams are the key to detecting glaucoma early enough for successful preventive treatment.
The American Academy of Ophthalmology recommends a comprehensive eye exam for all adults starting at age 40, and every three to five years after that if you don't have any glaucoma risk factors. After age 60, you should be screened every year. If you are African-American or have other risk factors for glaucoma, your doctor likely will recommend periodic eye exams starting between ages 20 and 39, and every one to two years after age 40.
In addition, be aware that a severe headache or pain in your eye or eyebrow, nausea, blurred vision, or rainbow halos around lights may be the symptoms of an acute angle-closure glaucoma attack. If you experience two or more of these symptoms together, seek immediate care at an emergency room or an eye doctor's (ophthalmologist's) office right away.
Prevention
* Get regular eye care. Regular comprehensive eye exams can help detect glaucoma in its early stages before irreversible damage occurs. As a general rule, have comprehensive eye exams every three to five years after age 40 and every year after age 60. You may need more frequent screening if you have glaucoma risk factors. Ask your doctor to recommend the right screening schedule for you.
* Treat elevated eye pressure. Glaucoma eyedrops can significantly reduce the risk that elevated eye pressure will progress to glaucoma. To be effective, these drops must be taken regularly even if you have no symptoms.
* Control your weight and blood pressure. Studies have shown that insulin resistance — which may result from hypertension and obesity — is linked to elevated intraocular pressure.
* Wear eye protection. Serious eye injuries can lead to glaucoma. Wear eye protection when you use power tools or play high-speed racket sports on enclosed courts, or otherwise risk being hit in the eye.
Complications
If left untreated, glaucoma will cause progressive vision loss, typically in these stages:
* Blind spots in your peripheral vision
* Tunnel vision
* Total blindness
Preparing for your appointment
In most cases, glaucoma doesn't cause any noticeable symptoms until the disease has caused permanent damage. Ask your primary care doctor how often you should see an eye doctor (ophthalmologist) for a comprehensive eye exam and stick with that schedule.
If you have any new eye symptoms or vision problems, make an appointment with your ophthalmologist or ask your doctor for a referral.
Here's some information to help you get ready for your appointment, and what to expect from your doctor.
What you can do
* List any symptoms you've been having, and for how long.
* Write down your key medical information, including other conditions with which you've been diagnosed and all medications and supplements you're taking.
* List any history of eye problems, such as vision changes or eye discomfort.
* Write down questions to ask your doctor. Creating your list of questions in advance can help you make the most of your time with your doctor.
Below are some basic questions to ask your doctor. If any additional questions occur to you during your visit, don't hesitate to ask.
* Do I have signs of glaucoma?
* What tests do I need to confirm a diagnosis?
* What treatment approach do you recommend?
* Do I need to follow any activity restrictions?
* What other self-care measures should I be taking?
* What is the long-term outlook in my case?
* How often should I be seen for follow-up care?
* Should I see a specialist?
* I have these other health conditions. How can I best manage them together?
What to expect from your doctor
A doctor who sees you for possible glaucoma is likely to ask you a number of questions, including:
* Have you had any eye discomfort or vision problems?
* Do you have any other signs or symptoms that concern you?
* Do you have any family history of eye problems, including glaucoma?
* What eye screening tests have you had, and when?
* Have you been diagnosed with any other medical conditions?
* What medications are you currently taking, including vitamins and supplements?
Tests and diagnosis
These are some of the tests that can establish a diagnosis of glaucoma:
* Measuring intraocular pressure. Tonometry is a simple, painless procedure that measures your intraocular pressure, after numbing your eyes with drops. It is usually the initial screening test for glaucoma.
* Test for optic nerve damage. To check the fibers in your optic nerve, your eye doctor uses instruments to look directly through the pupil to the back of your eye. This can reveal slight changes that may indicate the beginnings of glaucoma.
* Visual field test. To check whether your visual field has been affected by glaucoma, your doctor uses a special test to evaluate your side (peripheral) vision.
* Measuring cornea thickness (pachymetry). Your eyes are numbed for this test, which determines the thickness of each cornea, an important factor in diagnosing glaucoma. If you have thick corneas, your eye-pressure reading may read higher than normal even though you may not have glaucoma. Similarly, people with thin corneas can have normal pressure readings and still have glaucoma.
* Other tests. To distinguish between open-angle glaucoma and angle-closure glaucoma, your eye doctor may use a technique called gonioscopy in which a special lens is placed on your eye to inspect the drainage angle. Another test, tonography, can measure how quickly fluid drains from your eye.
Treatments and drugs
Glaucoma treatments reduce intraocular pressure by improving aqueous outflow, reducing the production of aqueous, or both. Glaucoma can't be totally cured, and damage caused by the disease can't be reversed, but treatment and regular checkups can prevent visual loss in people with very early glaucoma. If visual loss has already occurred, treatment can slow or prevent further vision loss.
Eyedrops
Glaucoma treatment often starts with medicated eyedrops. Be sure to use the drops exactly as prescribed. Otherwise, your optic nerve damage could get even worse. If your doctor prescribes more than one type of eyedrop, make sure to ask how long to wait between applications. Because some of the eyedrops are absorbed into your bloodstream, you may experience side effects unrelated to your eyes. To minimize this absorption, close your eyes for one to two minutes after putting the drops in. Press lightly at the corner of your eye near your nose to close the tear duct for one or two minutes, and wipe off any unused drops from your eyelid.
The types of most commonly prescribed eyedrops include:
* Prostaglandin-like compounds. These eyedrops increase the outflow of aqueous humor. Examples include latanoprost (Xalatan) and bimatoprost (Lumigan). Possible side effects include mild reddening and stinging of the eyes and darkening of the iris, changes in the pigment of the eyelid skin, and blurred vision from swelling of the retina.
* Beta blockers. These reduce the production of aqueous humor. Examples include timolol (Betimol, Timoptic), betaxolol (Betoptic) and metipranolol (Optipranolol). Possible side effects include difficulty breathing, slowed pulse, hair loss, lower blood pressure, impotence, fatigue, weakness, depression and memory loss. If you have asthma, bronchitis or emphysema, medications other than beta blockers may be recommended because beta blockers may worsen breathing problems. Your doctor also may recommend avoiding beta blockers if you're taking insulin for diabetes.
* Alpha-agonists. These reduce the production of aqueous humor and increase drainage. Examples include apraclonidine (Iopidine) and brimonidine (Alphagan). Possible side effects include fatigue, dizziness, red, itchy or swollen eyes, dry mouth and allergic reactions.
* Carbonic anhydrase inhibitors. These also reduce the production of aqueous humor. Examples include dorzolamide (Trusopt) and brinzolamide (Azopt). Frequent urination and a tingling sensation in the fingers and toes are possible side effects, occurring more often with oral carbonic anhydrase inhibitors than with anhydrase inhibitor eyedrops. If you have an allergy or sensitivity to sulfa drugs, don't use these medications unless there's no alternative.
* Miotic or cholinergic agents. These also increase the outflow of aqueous humor. Examples include pilocarpine (Isopto Carpine) and carbachol (Isopto Carbachol). Possible side effects are pain around or inside the eyes, brow ache, blurred or dim vision, nearsightedness, allergic reactions, a stuffy nose, sweating, increased salivation, and occasional digestive problems.
* Epinephrine compounds. These compounds, such as dipivefrin (Propine), also increase the outflow of aqueous humor. Possible side effects include red eyes, allergic reactions, palpitations, increased blood pressure, headache and anxiety.
Oral medications
If eyedrops alone don't bring your eye pressure down to the desired level, your doctor may also prescribe an oral medication, usually in the form of a carbonic anhydrase inhibitor. Take these pills with meals to reduce side effects.
Initially, carbonic anhydrase inhibitors may cause frequent urination and a tingling sensation in your fingers and toes. After several days, these symptoms usually disappear. Other possible side effects of carbonic anhydrase inhibitors include rashes, depression, fatigue, kidney stones, lethargy, stomach upset, a metallic taste in carbonated beverages, impotence and weight loss.
Drugs that protect the optic nerve
Lowering the intraocular pressure provides only a partial solution when it comes to preserving vision in people with glaucoma. Ongoing clinical trials are evaluating certain drugs that may help protect the optic nerve from damage associated with glaucoma.
Surgery
You may need surgery to treat glaucoma if you can't tolerate medications or if they're ineffective. Sometimes a single surgical procedure may not lower eye pressure enough, in which case you'll need to continue using eyedrops or have another operation. Possible complications from glaucoma surgery may include infection, bleeding, abnormally high or low eye pressure, and, potentially, loss of vision. Having eye surgery may also speed up the development of cataracts. Most of these complications can be effectively treated.
Surgeries used to treat glaucoma include:
*
Laser surgery. In the last couple of decades, a procedure called trabeculoplasty (truh-BEK-u-lo-plas-tee) has had an increased role in treating open-angle glaucoma. After giving you an anesthetic eyedrop, the doctor uses a high-energy laser beam to open clogged drainage canals and help aqueous humor drain more easily from the eye.
This is an office procedure lasting 10 to 20 minutes, and you can usually resume normal activities without discomfort. The doctor will need to check your eye pressure several times in the following weeks. It may take a few weeks before the full effect of the surgery becomes apparent.
In almost all cases, laser surgery for glaucoma initially lowers intraocular pressure. After time, however, intraocular pressure may begin to increase.
*
Filtering surgery. If eyedrops and laser surgery aren't effective in controlling your eye pressure, you may need an operation called a filtering procedure, usually in the form of a trabeculectomy (truh-bek-u-LEK-tuh-me).
This procedure is done in a hospital or an outpatient surgery center. You'll receive eyedrops, a medication to help you relax and usually an injection of anesthetic to numb your eye. Using delicate instruments under an operating microscope, your surgeon creates an opening in the sclera — the white of your eye — and removes a small piece of the trabecular meshwork. The aqueous humor can now freely leave the eye through this opening. As a result, your eye pressure will be lowered. The hole is covered by the conjunctiva, so trabeculectomy leaves no open hole in your eye. This procedure works best if you haven't had any previous eye surgery. Your doctor will check your eye during several follow-up visits, and you'll need to use antibiotic and anti-inflammatory eyedrops to fight infection and scarring of the newly created drainage opening.
Another procedure performed within the eye removes a targeted strip of trabecular meshwork with a tiny electrocauterizing tool. The tool is introduced into the eye's drainage canal through a 1/16-inch (1.6-millimeter) incision at the edge of the cornea. A predetermined section of the trabecular meshwork can be removed from the inside of the eye with this instrument. Research indicates this procedure can be effective. It continues to be investigated.
* Drainage implants. Another type of operation, called drainage implant surgery, may be an option for people with secondary glaucoma or for children with glaucoma. Drainage implant surgery takes place in a hospital or an outpatient clinic. The eye surgeon inserts a small silicone tube in your eye to help drain aqueous humor. After the surgery, you'll wear an eye patch for 24 hours and use eyedrops for several weeks to prevent infection and scarring.
Treating acute angle-closure glaucoma
Acute angle-closure glaucoma is a medical emergency. When you come in with this condition, doctors may administer several medications to reduce eye pressure as quickly as possible. You'll also likely have an iridotomy, a laser procedure that creates a small hole in your iris so that aqueous humor can pass into the trabecular meshwork. Many doctors recommend an iridotomy on the other eye at a later date because of the high risk that its drainage angle will close as well.
http://www.mayoclinic.com/health/glaucoma/DS00283/DSECTION=treatments%2Dand%2Ddrugs