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A B C D E F G H I J K LM N O P Q R S T U V W X Y Z 0-9
(A-Z listing includes diseases, conditions, tests and procedures)


Glaucoma: What You Need to Know

  • Glaucoma is an eye disease that causes permanent vision loss, progressively affecting peripheral and then central vision. It can affect one or both eyes.

  • If left untreated, glaucoma can cause blindness.

  • There are several types of glaucoma, with open-angle glaucoma being the most common form.

  • There are no noticeable symptoms in the early stages of most types of glaucoma, so by the time symptoms are recognized, considerable vision may already be lost.

  • Glaucoma is the second leading cause of blindness worldwide.

  • You are more likely to be diagnosed with glaucoma if you have a family member with glaucoma.

  • A common misconception is that glaucoma is caused by high eye pressure. Eye pressure is an important risk factor for glaucoma, but almost half of all glaucoma cases occur at normal eye pressure.

What is glaucoma?

Glaucoma is a disease that damages the optic nerve. The optic nerve is a bundle of nerve fibers that connects the eye with the brain and is therefore vital for good eyesight. Glaucoma first affects the peripheral (side) vision and can eventually damage central vision, which is important for reading and other important tasks. Glaucoma can lead to progressive and permanent vision loss. While the vision loss from glaucoma is permanent, early treatment can help slow or stop its progression.

Types of Glaucoma

  • Open-Angle Glaucoma. This is the most common type of glaucoma, in which the front of the eye’s drainage canals are working properly but are clogged farther down the system. People often do not notice symptoms because peripheral vision is affected first, with no change in clarity or central vision. Tunnel vision occurs in the advanced stages of the disease. Open-angle glaucoma progresses slowly, often taking years for any sight loss to occur.

  • Angle-Closure Glaucoma. Angle-closure glaucoma can be either chronic or acute. It accounts for less than 10 percent of all glaucoma diagnoses.

    • Acute angle-closure glaucoma (also called closed-angle). This condition is a medical emergency, and treatment should be sought immediately. A sudden increase in eye pressure occurs due to trapped fluid at the front of the eye. Severe pain in or above the eye, nausea, and blurred vision are some of the symptoms. Without treatment, blindness can occur within hours to days.

  • Congenital glaucoma. Infants are born with a defect that slows the normal drainage of fluid in their eyes. They might have cloudy eyes, sensitivity to light or excessive tearing.

  • Juvenile glaucoma. This type of glaucoma occurs in adolescents and young adults.

  • Secondary glaucoma. Secondary glaucoma can be open-angle or angle-closure, and can be caused by a variety of conditions.

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Adults should have a routine eye exam every one to two years or immediately upon experiencing any problems, such as injury to the eye, visual changes, pain, flashes of light, new floaters or tearing. If you have high blood pressure, diabetes or a family history of eye disease, consult with your ophthalmologist or optometrist on how often you should be seen.

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Risks Factors for Glaucoma

Anyone can develop glaucoma. However, some people are at higher risk than others. The risk factors for glaucoma are:

  • Age. People 60 and older are more at risk for developing glaucoma.

  • Family history. People with a family history of glaucoma are more likely to develop the disease. Open-angle glaucoma is hereditary, meaning you are at a much higher risk if members of your immediate family have glaucoma.

  • Race. African-Americans, Hispanics and Asians have higher incidences of glaucoma than people of European descent.

  • Eye injury. Injury to the eye can cause glaucoma, either immediately after the injury or years later. Injuries that “bruise” or puncture the eye can cause secondary glaucoma.

  • High fluid pressure inside the eyes. People with a high fluid pressure inside the eyes are at an increased risk.

  • Steroid use. Prolonged use of steroids (for example, eye drops, pills, inhalers and creams) has shown to increase the risk of developing glaucoma.

Glaucoma Symptoms

Most people who have glaucoma do not notice any symptoms until they start to lose some of their central vision, which is important for reading and recognizing faces. As the optic nerve is damaged by glaucoma, small blind spots may begin to develop in your peripheral (side) vision. Many people do not notice the blind spots until significant vision loss has already occurred. If left untreated, central vision is eventually affected.

Acute angle-closure glaucoma produces noticeable symptoms because of a rapid buildup of pressure in the eye. If you experience any of the following symptoms, you need to seek treatment immediately:

  • Blurred or narrowed field of vision

  • Halos or “rainbows” around lights

  • Headache

  • Nausea

  • Severe pain in the eyes

  • Vomiting

More Information About Glaucoma from Our Experts

Glaucoma: What Every Patient Should Know cover

Glaucoma: What Every Patient Should Know

Glaucoma: What Every Patient Should Know can help you answer the many questions you might have about this common eye disease. Written by Dr. Harry Quigley, this guide provides authoritative answers, easily understood explanations, helpful suggestions, and life-style advice that can take the stress out of dealing with glaucoma, and should maximize the chance that no further injury to your ability to see will occur. All proceeds are used to support research within the Glaucoma Center of Excellence.

Glaucoma Diagnosis

A comprehensive exam to detect glaucoma consists of the following:

  • Visual field (perimetry). This test measures a person’s side or peripheral vision.

  • Optic nerve images. The optic nerve can be seen by looking in the eye from the front. There are a number of devices that can collect images of the nerve to help determine whether or not it is damaged.

  • Visual acuity test. The common eye chart test measures how well you can see at various distances.

  • Gonioscopy. A small, hand-held lens is used to show whether the space needed to drain fluid in the front of the eye is open (consistent open-angle glaucoma) or closed (consistent with angle-closure glaucoma).

  • Tonometry. Measuring the pressure inside the eye. This can be accomplished using a variety of methods.

  • Corneal thickness (pachymetry). The thickness of your cornea is measured using ultrasonic waves and is important to your doctor in diagnosing and managing glaucoma.

  • Pupil dilation (Ophthalmoscopy). The pupil is widened with eye drops to allow a close-up examination of the optic nerve and retina in the back of the eye.

Glaucoma Treatment

While none of these treatments can cure or reverse the damage already caused by glaucoma, they can help slow or stop glaucoma from getting worse. Currently available treatments are designed to lower the pressure in the eye, since this is the one factor that is known to slow down or stop the disease:

  • Medicines. Medicines in the form of eye drops, and sometimes pills, are the most common treatment for glaucoma. Some medicines cause the eye to produce less fluid, while others lower pressure by helping fluid drain from the eye. Regular use of medication is essential for the treatment to work.

  • Laser surgery (trabeculoplasty). In this outpatient procedure, a laser is used to widen the fluid drainage holes, lowering the pressure in the eye.

  • Surgery. Surgery is often conducted after medicine and laser surgery have failed to control pressure in the eye. There are a number of surgical options to manage glaucoma, but all are designed to create a new opening for fluid to drain from the eye.

Eye Drop Adherence | Glaucoma Research at the Wilmer Eye Institute

Michael Boland, M.D., Ph.D., discusses the importance of taking glaucoma medications as prescribed and the patient education programs implemented at Wilmer as a result of his research.

Surgical Improvements at the Wilmer Eye Institute

Harry Quigley, M.D., the director of the Glaucoma Center of Excellence at the Wilmer Eye Institute at Johns Hopkins, summarizes recent research on glaucoma surgery at Wilmer. The institute is pioneering new techniques to improve outcomes for patients with glaucoma.

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