What is Glaucoma?

The info listed below should not be used for diagnosis or treatment of any medical condition or during a medical emergency. Please consult a licensed medical professional for diagnosis and treatment of all medical conditions. This is not intended to replace the advice of a doctor and Braille Works disclaims any liability for the decisions you make based on this information. We have assembled this content from online and offline sources. Links to source websites are provided for documentation and informational reasons but do not represent our endorsement. If you know of a discrepancy on this page please contact us so we can amend the entry.

Glaucoma refers to a group of eye conditions that can develop when too much fluid pressure builds up inside of the eye (Intraocular Pressure). Increased IOP can lead to damage of the optic nerve, which is the nerve that communicates visual information to the brain. Continuing damage to the optic nerve will eventually cause loss of vision and if left untreated, can result in total blindness within a few years.

Glaucoma tends to be hereditary and symptoms may or may not show up until later in life. A lot of people who have Glaucoma show little-to-no early symptoms so if you are over the age of 40 and/or have family members with a history of Glaucoma, it’s important to have a complete eye exam with your ophthalmologist at least every 1-2 years so any problems can be diagnosed and treated before long-term loss of vision occurs. Glaucoma affects 1 in 200 people who are 50 years old or younger and 1 in 10 people who are over the age of 80. Worldwide, Glaucoma is the second leading cause of blindness after cataracts and is also the leading cause of blindness among African Americans. With early detection and proper medical treatment, it’s possible to slow the progression of Glaucoma.

Causes of Rising Eye Pressure

Intraocular Pressure (IOP) increases when “Aqueous Humor” fluid rises in the eye’s anterior chamber (area between the cornea and iris). Aqueous Humor fluid will normally flow out through a channel in the front of the eye in an area called the anterior chamber angle, but if the channel becomes blocked, fluid builds up over time, leading to Glaucoma. The exact cause of this blockage is currently unknown, but doctors agree that it’s inherited from parents to children in most cases.

Some less common causes of Glaucoma include severe eye infections, chemical injury to the eye, blood vessels blockages and occasionally; eye surgeries to correct other conditions can lead to Glaucoma. Typically Glaucoma will occur in both eyes, but the extent can vary in each eye.

Types of Glaucoma

Glaucoma is the 2nd most common cause of blindness in the United States. In all, there are four major types of Glaucoma:

  • Open-Angle Glaucoma (Chronic): Open-Angle Glaucoma (also known as Wide-Angle Glaucoma) accounts for 90% of Glaucoma cases in the United States and is the most commonly diagnosed type worldwide. It is painless and does not include acute attacks. Gradually progressive visual field loss and optic nerve changes are the only related signs. Structures of the eye(s) appear to be normal but fluid in the eye isn’t flowing properly through the eye’s drain, called the trabecular meshwork. As fluid rises slowly over time, pressure increases and pushes on the optic nerve. Open-Angle Glaucoma usually runs in the family and people of African descent are three times more likely to develop it.
  • Angle-Closure Glaucoma (Acute): Also known as Closed-Angle or Narrow-Angle Glaucoma, this type is less common in the U.S. but accounts for up to 50% of Glaucoma cases in other countries (especially Asian countries). Acute Glaucoma occurs when the Aqueous Humor fluid is suddenly blocked from exiting the eye; causing a severe and painful rise in the pressure. Unlike the slow, painless damage of Open-Angle Glaucoma; this type is highly painful and should be considered an emergency. If you’ve had Acute Glaucoma in one eye, you’re second eye is at risk and your ophthalmologist is likely to recommend preventive treatments. Certain medications and eye drops have been known to trigger Acute Glaucoma attacks. Women are three times more likely than men to develop Acute Angle-Closure Glaucoma because of their shallower anterior chambers and many East Asian groups are more prone to developing it for the same reason. Some of the symptoms include red eye, sudden ocular pain, seeing circles or halos around lights, sudden decrease in vision, high levels of intraocular pressure, and nausea.
  • Congenital Glaucoma: Congenital Glaucoma is present at birth and is the result of abnormal eye development during pregnancy. It’s often inherited from family and primarily treated with surgery using general anesthesia so the patient feels no pain. The cause is a highly distorted drainage system and symptoms are usually not noticed until the child is a few months old. Symptoms include cloudiness of the eye(s), enlargement of one or both eyes, extra sensitivity to light, excessive tearing and red eye(s). Infants with Congenital Glaucoma typically do well as long as surgery is done early.
  • Secondary Glaucoma: Many factors can cause Secondary Glaucoma. The most prevalent factors are eye diseases such as Uveitis, systemic diseases, trauma and the prolonged use of drugs such as corticosteroids (steroids). Getting treatment of the underlying disease can help symptoms disappear but it depends on the severity of the disease which is causing the condition.


Open-Angle Glaucoma (Chronic):

  1. Most people experience no symptoms
  2. There can be a slow loss of peripheral vision (sometimes known as “tunnel vision”)
  3. Advanced cases can lead to complete blindness

Angle-Closure Glaucoma (Acute):

  1. Sudden, severe pain in the eye
  2. Seeing “rainbow-like” circles or halos around lights
  3. Decreased, cloudy and/or blurry vision
  4. Eye feels as though it is swollen
  5. Red eye
  6. Nausea and vomiting
  7. Symptoms can come & go at first or progressively become worse

Congenital Glaucoma:

  1. Excessive tearing
  2. Red eye
  3. Light sensitivity
  4. Front of eye looks cloudy
  5. Enlargement of one or both eyes
  6. Symptoms usually become noticeable once the child is a few months old

Who Is More Susceptible To Get Glaucoma?

Glaucoma occurs most often in adults 40 years of age and older but can also occur in young adults, children, and even infants. African-Americans experience Glaucoma more frequently; at an earlier age and with greater loss of vision than most segments of the population. Others with an increased risk of Glaucoma include people of Hispanic, Japanese, Irish, Russian, Inuit or Scandinavian descent. Other factors include age, family history of glaucoma, poor vision, diabetes, and the taking of certain steroid medications, such as prednisone.

How Is Glaucoma Diagnosed?

Thankfully, Glaucoma tests are painless and take very little time. An Ophthalmologist will test vision and examine the eyes through dilated pupils to diagnose Glaucoma. The eye exam will typically focus on the optic nerve because of its’ particular appearance during Glaucoma development. Doctors also perform a visual field test to determine if there is any loss of peripheral vision and utilize a procedure called Tonometry to check for eye pressure.

Glaucoma Treatments

Treatments for Glaucoma include prescription eye drops, laser surgery or microsurgery. Be sure to speak with your ophthalmologist first to find out which Glaucoma treatment is right for you or your family.

  • Prescription Eye Drops: Eye drops are prescribed to either reduce formation of fluid in the front of the eye or increase fluid outflow. Side effects of Glaucoma eye drops have been known to include allergies, irritated eyes, blurred vision, red eye, and brief periods of stinging. Research has shown Glaucoma drugs (including eye drops) may affect the heart and lungs so be sure to tell your doctor of any other medications you currently take or are allergic to.
  • Laser Surgery for Glaucoma: The benefits of laser surgery treatments for people with Glaucoma will depend on what type of Glaucoma you or your loved one has. For people with Open-Angle Glaucoma, laser surgery will slightly increase the outflow of the fluid from the eye. People who have Angle-Closure Glaucoma will benefit from the elimination of fluid blockage in the eye.
  • Microsurgery for Glaucoma: Using an operation called a Trabeculectomy; a new channel is created to drain eye fluid, resulting in a reduction of the intraocular pressure that causes glaucoma. This surgical procedure is known to fail at times so some patients have had to repeat it. Some other known complications of Microsurgery for Glaucoma are bleeding or infection, as well as temporary or permanent vision loss.


Even with all of today’s current medical advances, Open-Angle Glaucoma cannot be cured. However, symptoms can be managed by closely following your doctor’s instructions. Regularly scheduled check-ups are needed on an ongoing basis to prevent blindness from occurring.

Glaucoma Prevention

Unfortunately, Glaucoma cannot be prevented but as long as it is diagnosed and treated early, the disease can be controlled.

What Does the Future Hold for People with Glaucoma?

The majority of people with Glaucoma will not go completely blind as long as they follow their doctors’ treatment plan and have eye exams on a regular basis. Currently, the loss of vision caused by Glaucoma is irreversible and can’t be restored. However, successfully lowering the eyes’ pressure through treatments can prevent further visual loss.

Contact Your Optometrist

If you have severe eye pain or a sudden loss of vision, especially loss of peripheral vision, contact your Optometrist or health care provider as soon as possible. If you have risk factors for Glaucoma but haven’t been screened for the condition, it would be a good idea to schedule an appointment with your doctor. If you think you’re at high risk for Glaucoma, speak with your Optometrist about your prevention options.


  1. Giaconi JA, Law SK, Caprioli J. Primary Angle-Closure Glaucoma. In: Tasman W, Jaeger EA, eds. Duane’s Ophthalmology. 15th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2009:chap 53.
  2. Anderson DR. The Optic Nerve in Glaucoma. In: Tasman W, Jaeger EA, eds. Duane’s Ophthalmology. 15th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2009:chap 48.
  3. Mandelcorn E, Gupta N. Lens-Related Glaucomas. In: Tasman W, Jaeger EA, eds. Duane’s Ophthalmology. 15th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2009:chap 54A.
  4. Kwon YK, Caprioli J. Primary Open-Angle Glaucoma. In: Tasman W, Jaeger EA, eds. Duane’s Ophthalmology. 15th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2009:chap 52.


  1. PubMed Health
  2. WebMD
  3. Wikipedia

Eye and Vision Conditions