What is glaucoma?

Glaucoma is an eye disorder that can affect the pressure inside the eye. In a healthy eye, clear fluid constantly flows in and out to nourish the eye’s tissues. But when fluid stops draining, it builds up and creates too much pressure within the eye. Over time, too much pressure can damage the optic nerve, which is necessary for good vision.

If left untreated, glaucoma can lead to vision loss and blindness — which is why early detection and proper treatment are key. After cataracts, glaucoma is the second leading cause of blindness worldwide.

Because glaucoma is an eye disease that can potentially cause blindness, it’s important to have your eyes checked by your eye doctor each year — especially those who have a higher risk of developing glaucoma. 

Types of glaucoma

There are several types of glaucoma:

• Open-angle glaucoma is the most common form of glaucoma and affects almost 3 million Americans. With this condition, the pressure in the eye increases over time.
• Angle-closure glaucoma is a less common type of glaucoma that causes a rapid and sudden increase in eye pressure.
• Normal-tension glaucoma damages the eye’s optic nerve, despite normal eye pressure.
• Congenital glaucoma is a rare condition that develops after birth due to a defect in the eye’s canals.
  
  

Glaucoma symptoms and causes

Glaucoma in its early stages will cause no pain and show no signs or symptoms. However, as the condition progresses, a person with glaucoma may notice their vision gradually worsening, along with the following symptoms:

• Blurred vision
• Presence of halos around lights
• Loss of peripheral vision, or side vision
• Difficulty focusing on objects

Having these symptoms does not mean you have glaucoma. However, it’s still important to talk to your eye doctor, as these could be signs of an underlying health issue.

Causes of glaucoma

Although the actual cause of glaucoma is unknown, it occurs when there’s a buildup of fluid in the eye. However, nearly half of all glaucoma cases occur in those with normal eye pressure.

Those who have the highest risk for glaucoma include:

• People over age 60, especially Mexican Americans
• African Americans over age 40
• People with diabetes
• Individuals who have experienced a serious eye injury
• Anyone with a family history of glaucoma
• Anyone who takes corticosteroid medications, such as prednisone

If you are at a greater risk for developing glaucoma, it’s important to have a complete eye exam, including dilated pupils, by an ophthalmologist every one to two years.

Diagnosing glaucoma and glaucoma tests

As the area’s leading eye specialists, our optometry and ophthalmology team is experienced in diagnosing and treating glaucoma at all stages.

In addition to reviewing your medical history and examining your eyes, your eye doctor will conduct the following tests to spot any concerns early:

• Eye chart test – which checks how well you see from a distance.
• Dilated eye exam – which uses drops to open up your pupils. With the help of a magnifying lens, your eye doctor can better examine the back of your eye to check the retina and optic nerve for damage.
• Visual field test – which measures your side vision (peripheral vision).
• Tonometry test – which uses a puff of air to measure the pressure in your eye.
• Pachymetry test – which measures the thickness of your cornea (the outer layer of the eye).