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What Is Glaucoma?

Glaucoma is a group of eye diseases that damage the optic nerve. The optic nerve is the part of your eye that carries information defining what you see to your brain. Your brain then turns the information into images.

Though there are probably several factors that contribute to glaucoma, the one we understand the best is eye pressure.  With glaucoma, fluid builds up in your eye and increases pressure. This increased pressure damages the optic nerve over time. Without treatment, optic nerve damage can cause vision loss and eventual blindness.  

Around 3 million people in the United States have glaucoma. The disease mostly affects adults, but glaucoma can occur in people of any age. Glaucoma is hereditary (tends to run in families). You should see an optometrist or ophthalmologist for glaucoma screening if you have a family member with glaucoma.

Cataracts vs. Glaucoma

A cataract is a disease affecting your lens, the clear curved structure at the front of your eye behind your pupil. Glaucoma affects your optic nerve.

Both cataracts and glaucoma can cause vision problems. Cataracts tend to affect your general, overall vision, while glaucoma affects your outer (peripheral) vision first then moves inward.

Pressure on the Optic Nerve

How Fluid Circulates in the Eye

Find a Glaucoma Doctor

Why Choose University of Utah Health?

The John A. Moran Eye Center is the largest eye center in the Mountain West region. We offer the full spectrum of diagnostic tools and treatments for glaucoma. We are also home to the Alan S. Crandall Center for Glaucoma Innovation, leading the way to better diagnostics, safer and more effective therapies and surgical devices, a deeper understanding of glaucoma and its genetics, and expanded access to care.

Your care is in the hands of specialists known nationally and internationally for their glaucoma expertise. We research new glaucoma surgeries, conduct clinical trials, and regularly speak at national and international meetings. Patients from the Mountain West region and beyond come to us for complex glaucoma needs.

Glaucoma Symptoms

Most types of glaucoma cause subtle, gradual symptoms that often go unnoticed.  The first sign of glaucoma can be a slight loss of peripheral vision. Glaucoma progresses very slowly, so people tend to adjust to this slight loss without realizing that it’s getting worse. Many people have significant vision loss by the time they realize they could have glaucoma. At this point, people with glaucoma may experience “tunnel vision,” a very restricted, narrow field of vision.

A thorough clinical examination can detect glaucoma symptoms before you notice them. Getting routine screening eye exams is crucial, especially if you have a higher risk of glaucoma.

One type of glaucoma, acute angle-closure glaucoma, can produce sudden and noticeable symptoms. It causes rapid pressure buildup in your eye. People with this type of glaucoma may experience these symptoms:

  • Blurred or narrowed field of vision
  • Halos around lights that may look like rainbows
  • Headache
  • Nausea
  • Severe eye pain
  • Vomiting

Seek medical treatment immediately if you experience any symptoms of acute angle-closure glaucoma. This type of glaucoma can cause blindness quickly without treatment.

Does Glaucoma Cause Blindness?

Yes, without treatment, glaucoma causes irreversible blindness. Researchers are studying ways to regenerate the optic nerve and restore vision in people who have experienced blindness due to glaucoma.

What Causes Glaucoma?

Some people have glaucoma that develops because of inflammation or a traumatic injury. In most cases, however, glaucoma develops with no known cause. You may be more likely to develop glaucoma if any of these traits apply to you:

  • You are 50 or older.
  • You are a long-term user of steroids or cortisone.
  • You are of African, Hispanic, or Mediterranean descent.
  • You are severely nearsighted.

The disease is also more likely to occur in people with certain health problems:

How to Test for Glaucoma

Diagnosing glaucoma may take several tests. Your initial visit may be lengthy. First, we will ask you for a complete medical history. Then, our specialists use several tests designed to detect glaucoma in its early stages:

  • Visual acuity test: The common eye chart test helps us measure your vision at various distances.
  • Slit lamp examination: We will use a microscope to examine the front part of your eye.
  • Tonometry: We will measure your eye pressure using brief puffs of air, a small probe, or an electronic device.
  • Pupil dilation: We will place eye drops that widen your pupil. This helps to examine your retina (tissue layer at the back of your eye) and optic nerve (nerve that carries information from your eyes to your brain).
  • Optical coherence tomography (OCT): An OCT uses light waves to take pictures of your retina and create a map of the optic nerve. This can help us measure the thickness of your optic nerve. 
  • Visual field test: You will place your chin in a machine where you look at flashing lights in the center and on the sides of a screen. You will push a button when you see the lights. This test can help measure your peripheral vision.
  • Pachymetry: An electronic device that measures the thickness of your cornea, which can affect the measurement of your eye pressure.
  • Gonioscopy: A special mirror is used to evaluate the drainage angle of your eye. 

Schedule an Appointment

Call 801-581-2352 to request an appointment with a comprehensive ophthalmologist. Your provider may also request a referral to a glaucoma specialist.


What is Ocular Hypertension?

Ocular hypertension is when pressure inside of the eye is higher than normal. Ocular hypertension is not considered a disease by itself, but it can lead to a condition known as glaucoma.
Find Out More

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