Glaucoma Causes & Symptoms

Glaucoma is like macular degeneration in that doctors do not understand the exact causes. However, certain factors, such as high intraocular pressure (IOP), family history, ethnic background, age or optic nerve appearance, put you at risk of developing glaucoma.

Remember that the most common glaucoma form – chronic glaucoma – progresses without any warning or until the permanent damage to your eyesight is already done. Only regular eye exams from an eye doctor to monitor glaucoma may protect your eyes against vision loss as a result of this eye disease.

For the latest news on glaucoma symptoms and causes, review the results of recent studies – "SLT as Primary Treatment for Glaucoma," "Does Night Sleeping Increase Eye Pressure in People With Glaucoma?" and "Exposure to Light May Worsen Glaucoma." Recent glaucoma news is listed in the Glaucoma News section of the Consumer Guide to Glaucoma.

There are several forms of glaucoma, and therefore glaucoma symptoms and glaucoma causes may vary depending on the type of glaucoma you have:

  • Primary open-angle glaucoma symptoms are almost non-existent. This type of glaucoma gradually and painlessly reduces your side (peripheral) vision while causing permanent damage to the eye's optic nerve, leading to eventual eyesight loss. This form of glaucoma develops due to an improper amount of fluid (aqueous humor) draining from the eye because of clogged drainage canals. If open-angle glaucoma remains untreated, you risk developing tunnel vision (the ability to see only the objects straight ahead).
  • Acute glaucoma symptoms, also known as angle-closure or narrow-angle glaucoma, include a sudden and quick rise in IOP accompanied by intense eye pain, eye redness, swelling and clouding of the cornea, and blurred vision. Furthermore, patients may experience haloes around lights. An emergency condition requiring immediate medical attention, an acute attack can be caused by any catalyst that leads to dilation of the pupil, such as entering a dark room or certain medications. The dilated pupil causes the iris to gradually block the drainage of the fluid from the eye, leading to elevated IOP. If your eye pressure is not reduced within a few hours, this acute attack may cause permanent vision loss.
  • Normal tension glaucoma manifests itself in quick optic nerve damage and visual field loss even though your IOP remains at normal levels. No one knows the exact causes of normal tension glaucoma, but many doctors believe this form of glaucoma may be a result of poor blood flow to the optic nerve. Patients with a family history of normal tension glaucoma are more prone to developing it.
  • Chronic narrow-angle glaucoma symptoms are similar to those of primary open-angle glaucoma where there is no warning of the impending disease until loss of vision occurs. This form of glaucoma occurs when the fluid (aqueous humor) cannot drain from the eye due to very narrow drainage angles that are blocked by the iris. Narrow-angle glaucoma can develop gradually, or progress quickly.
  • Congenital glaucoma occurs in babies since they are unable to communicate that there is something wrong with their vision. Parents need to keep an eye on symptoms such as cloudy, hazy eyes, etc. This form of glaucoma is usually caused by the improper development of the drainage system of the baby's eye. As a result, intraocular pressure increases, eventually leading to optical nerve damage and loss of vision.
  • Pigmentary glaucoma often progresses without symptoms. In some cases, patients may notice some pain and blurred vision after exercise. If you are a male in your twenties or thirties and nearsighted, you are at a higher risk of developing this form of glaucoma. In nearsighted patients, the iris pigment rubs on the eye's lens. As a result, iris particles get into the fluid (aqueous humor) and clog the drainage channels. The fluid stays in the eye and IOP rises, leading to optic nerve damage.
  • Secondary glaucoma may develop as a result of trauma to the eye or complications from medical conditions, such as diabetes. It can also be caused by certain types of drugs such as steroids.

Need More Glaucoma Info?

For in-depth information on glaucoma, please visit the Consumer Guide to Glaucoma.