We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.
Health

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

What is Normal-Tension Glaucoma?

By Cheryl Pokalo Jones
Updated: Feb 18, 2024
Views: 6,545
Share

High pressure inside the eye can damage the optic nerve, causing loss of vision and eventually blindness. This condition is called glaucoma, and several specific types of glaucoma exist. Although all glaucoma results in optic nerve damages because of intraocular pressure, most forms of glaucoma cause a rise in pressure. Normal-tension glaucoma, however, occurs when the pressure inside the eyeball is within the normal range but still damages the optic nerve.

The causes of normal-tension glaucoma are unknown. Vision loss is directly related to optic nerve damage, but why the nerve is damaged when pressure is within the normal range is unclear. Normal intraocular pressure has a measurement of 10-20 millimeters of mercury. An estimated one-third of cases of glaucoma involve normal intraocular pressure.

This condition is characterized by progressive damage to the optic nerve. As the damage worsens, the field of vision becomes narrower. Normal-tension glaucoma is difficult to diagnose. Standard glaucoma tests rely on steadily increasing intraocular pressure. Diagnosis of normal-tension glaucoma depends on careful examination and visual acuity tests.

Several theories have been proposed to explain why in some cases the optic nerve becomes damaged by normal pressure. One theory suggests that decreased blood flow causes cells in the optic nerve to die from a lack of oxygen and nutrients. Without the cells to carry the nerve impulses to the brain, vision suffers. An alternate theory cites weaknesses in the optic nerve that leaves the nerve particularly susceptible to pressure-related damage even when the pressure is within the normal range. Also, poor circulatory mechanisms might inhibit blood vessels from regulating pressure within the eye, causing damage.

Certain risk factors for normal-tension glaucoma have been identified. Anyone with a family history of any type of glaucoma is considered at risk for all types of glaucoma. Women are at a higher risk than men. The presence of a cardiovascular disease also raises a person’s risk. People of Japanese ancestry are particularly susceptible to the disease.

The optic nerve damage caused by any type of glaucoma is irreversible, so the goal of treatment is to prevent further damage. The treatment for normal-tension glaucoma is to keep the intraocular pressure as low as possible with medication. If medications are ineffective, laser or filtering surgery might be required. In some people, however, maintaining normal intraocular pressure is insufficient to prevent further damage. Damage to their optic nerves progresses regardless of low eye pressure.

Share
WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Editors' Picks

Discussion Comments
Share
https://www.wise-geek.com/what-is-normal-tension-glaucoma.htm
Copy this link
WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.