Glaucoma is a complicated disease that damages the optic nerve and leads to progressive, irreversible vision loss.  Though considered the second leading cause of blindness, there are actually several forms of glaucoma.  According to the Glaucoma Research Foundation, open-angle glaucoma is the most common form of glaucoma, accounting for at least 90% of all glaucoma cases and affecting about 3 million Americans.  It’s estimated that 1 in 2 people with this type of glaucoma don’t even know they have it.

While all forms of glaucoma require the help of an eye care professional, angle-closure glaucoma, a less common form, caused by blocked drainage canals, can result in a sudden rise in intraocular pressure and requires immediate medical attention.


In general, glaucoma initially has no symptoms. Pressure in the eye builds up gradually, and at some point, the optic nerve is damaged and peripheral vision is lost.  Sometimes people with later stages of glaucoma may bump into doorways or not see a car in a passing lane because their side vision is significantly affected.  Because there are no obvious glaucoma symptoms until the optic nerve is damaged and side (peripheral) vision is lost, it’s important to get annual, comprehensive eye exams to help detect signs of the disease.

Acute glaucoma symptoms can include:

  • Eye pain
  • Nausea and vomiting (accompanying severe eye pain)
  • Sudden onset of visual disturbance, often in low light
  • Blurred vision or vision loss
  • Halos around lights
  • Reddening of the eye

Unfortunately, by the time you notice glaucoma symptoms, they may be severe and are likely irreversible.


Some potential risk factors for glaucoma include:

  • High myopia (very severe nearsightedness)
  • Diabetes
  • Previous Eye surgery or injury
  • High blood pressure
  • Use of corticosteroids (e.g. eye drops, pills, inhalers and creams)

You may be at higher risk for glaucoma if you:

  • Have high eye pressure
  • Have a family history of glaucoma
  • Are 40 and older, and African American
  • Are 60 and older, especially Mexican Americans
  • Have a thin cornea

Early detection, through regular eye exams, is the key to protecting your vision from damage caused by glaucoma. During an examination for glaucoma, your eye care provider will check your intraocular pressure and evaluate your optic nerve. If your eye pressure is elevated or your optic nerve looks suspicious, your provider will likely perform specialized scans of your retina and optic nerve to determine if you have glaucoma.

The content of this article is for general informational awareness purposes only, and is not intended to be a substitute for professional advice, diagnosis, or treatment. Please consult your eyecare doctor or physician for actual advice, diagnosis, or treatment. This article is the work of the attributed author and does not necessarily represent the views or opinions of VSP. If you think you may have a medical emergency, call your doctor or 911 immediately.

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Dr. Marjorie Knotts is owner and lead optometrist at Knotts Optometry in Indianapolis, IN.