Medically reviewed by Steven H. Suh, MD, Director of Cataract Surgery. Reviewed October 23, 2026.
Glaucoma is a group of eye diseases that damage the optic nerve, the nerve that carries what you see from the eye to the brain, and it can cause vision loss and blindness. In most cases, it has no early symptoms, so the only way to find out whether glaucoma is present is a comprehensive dilated eye exam. Treatment cannot undo damage already done, but treatment that lowers eye pressure can often stop further damage and protect the vision you have.
Glaucoma at a glance
- What it is: a group of eye diseases that damage the optic nerve.
- Early symptoms: usually none.
- Later symptoms: loss of side vision, blind spots, and, without treatment, blindness.
- Most common type in the United States: open angle glaucoma, about 9 in 10 cases.
- How it is found: a comprehensive dilated eye exam with visual field testing.
- Treatment: medicines (usually eye drops), laser treatment, and surgery. At our office, glaucoma care includes pressure lowering eye drops and in office laser treatment (SLT and ALT).
- What treatment does: lowers eye pressure to stop further damage. It does not restore vision already lost.
What glaucoma is and what causes it
Glaucoma damages the optic nerve at the back of the eye. The front of the eye makes a clear fluid that drains out through an area called the drainage angle. When the fluid cannot drain fast enough, it creates pressure that pushes on the optic nerve. Over time that pressure damages the nerve, and the damage shows up first as lost side vision.
Scientists are not sure what causes the most common types of glaucoma. Many people with glaucoma have high eye pressure, and treatments that lower eye pressure slow the disease. Eye pressure alone does not define glaucoma, though. Some people with high eye pressure never develop it, and there is a type of glaucoma that develops in people whose eye pressure is normal. Normal eye pressure varies from person to person, which is why a single pressure reading is never the whole picture and why the exam looks at the optic nerve itself.
Glaucoma can affect one eye or both. There is no known way to prevent it, which is the reason regular dilated exams matter: they let your physician find it before it affects your vision.
The types of glaucoma
Glaucoma is grouped by what happens at the drainage angle and by whether another condition is behind it. The National Eye Institute describes the main types this way.
Open angle glaucoma
Open angle glaucoma is the most common type in the United States; about 9 in 10 people with glaucoma have this type. The drainage angle stays open, but fluid drains too slowly and pressure builds gradually. Most people have no symptoms until vision is already being lost, and the loss is slow enough that many do not notice it at first. Normal tension glaucoma is a form of open angle glaucoma that occurs in people with normal eye pressure; lowering pressure still helps slow it.
Angle closure glaucoma
Angle closure glaucoma, also called narrow angle glaucoma, happens when the outer edge of the iris, the colored part of the eye, blocks the drainage angle. When the block is sudden, pressure rises quickly and the result is a medical emergency; the symptoms are listed below under same day care. A slower form, chronic angle closure glaucoma, can develop with no symptoms at all and is found at an exam. The American Academy of Ophthalmology lists people who are farsighted, over age 50, female, or who have a family member with angle closure glaucoma among those at higher risk of it.
Secondary glaucomas
Secondary glaucoma is glaucoma caused by another condition. Examples include neovascular glaucoma (new blood vessels grow over the area where fluid drains, usually because of diabetes or high blood pressure), pigmentary glaucoma (pigment from the iris flakes off and blocks the drain), exfoliation glaucoma (deposits of extra material block drainage), uveitic glaucoma (inflammation inside the eye), and glaucoma after an eye injury. Steroid medicines can raise eye pressure as a side effect, so tell us about every medicine you take. Congenital glaucoma, present at birth, is rare.
Why glaucoma often has no symptoms
Open angle glaucoma takes side vision first, and side vision loss is easy to miss. The part of your field of view closest to your nose usually goes first, and the change is gradual. By the time a person notices that things off to the side are disappearing, the nerve damage is advanced and permanent. That is why half of the people who have glaucoma do not know they have it, according to the Centers for Disease Control and Prevention, and why having no symptoms is a reason to be checked rather than a reason to wait.
Blurred vision, trouble reading, and tired eyes are not typical early signs of open angle glaucoma. An exam finds glaucoma; symptoms usually do not.
Who is at risk for glaucoma
Anyone can get glaucoma, and some people are at higher risk. The National Eye Institute says you are at higher risk if you are over age 60, especially if you are Hispanic/Latino; if you are African American and over age 40; or if you have a family history of glaucoma. The Centers for Disease Control and Prevention adds people who have diabetes.
The American Academy of Ophthalmology’s 2025 guideline for primary open angle glaucoma lists further risk factors, among them elevated eye pressure, older age, nearsightedness (myopia), a thinner than average cornea, diabetes, and lower blood pressure. None of these means a person has glaucoma. Each is a reason to be examined and, if your physician recommends it, to be checked more often.
If you are at higher risk, the National Eye Institute recommends a comprehensive dilated eye exam every 1 to 2 years. Talk with us about your own risk and how often you should be seen.
Glaucoma and family history
Glaucoma runs in families. A family history of glaucoma raises your risk, and the National Eye Institute encourages people with glaucoma to tell their relatives to get checked. If a relative of yours has glaucoma, tell us when you schedule, because it affects how often you should be checked. The reverse is also true: if glaucoma is found at your exam, your family members should know so they can be checked.
How glaucoma is found
Glaucoma is found at a comprehensive dilated eye exam. Drops widen the pupils so the optic nerve can be examined directly, and a visual field test checks your side vision. A full glaucoma evaluation also measures your eye pressure, measures the thickness of your cornea, inspects the drainage angle with a special lens, and may photograph or scan the optic nerve so that changes can be tracked over time.
A pressure check alone is not enough. Glaucoma can be present at normal pressure, and high pressure can be present without glaucoma, so a pressure reading from a screening is a starting point, not an answer. An exam determines whether glaucoma is present and, if it is, how far it has progressed.
At Comprehensive EyeCare of Central Ohio, ophthalmologists and optometrists see patients in the same building, so a concern raised at a routine exam can be evaluated by a physician in the same office. Dilating drops may cause temporary blurred vision and light sensitivity, which may affect driving, so you may wish to arrange a ride and bring sunglasses.
How glaucoma is treated at Comprehensive EyeCare of Central Ohio
Treatment lowers eye pressure to slow or stop further damage to the optic nerve. Glaucoma is managed for life rather than resolved, and treatment does not bring back vision that has already been lost, but clinical trials have shown that lowering eye pressure reduces the risk of developing primary open angle glaucoma and slows its progression. The pressure goal is set for each person; the American Academy of Ophthalmology guideline describes a reasonable starting goal as a pressure 20 to 30 percent below the starting level, adjusted up or down as the disease is followed.
The National Eye Institute describes three kinds of treatment: medicines, usually prescription eye drops; laser treatment, which helps fluid drain out of the eye; and surgery, which a physician may suggest if medicines and laser treatment do not work. At our office, glaucoma care is managed by Dr. Suh, Director of Cataract Surgery, and Dr. Beckman, Director of Corneal Services, and includes:
- Pressure lowering eye drops, prescribed and adjusted at follow up visits. The National Eye Institute’s advice is plain: take the drops every day as prescribed, and tell your physician about side effects rather than changing or stopping them on your own.
- In office laser treatment. Selective laser trabeculoplasty (SLT) and argon laser trabeculoplasty (ALT) use a laser to help fluid drain from the eye and lower eye pressure, and both are performed in our office.
Glaucoma is a lifelong condition. Regular follow up visits, with pressure checks, visual field tests, and imaging over time, are part of treatment rather than an extra, because the only way to know that the pressure goal is holding is to measure it.
Glaucoma symptoms that need same day care
Most glaucoma gives no warning. One form does, and it is an emergency: acute angle closure glaucoma blocks the drainage angle suddenly, and eye pressure rises quickly. Call us right away at 614-890-5692, or go to an emergency room, if you have:
- sudden blurry vision
- severe eye pain
- a headache along with the eye pain
- nausea or vomiting
- a red eye
- rainbow colored rings or halos around lights
Outside office hours, call the same number and the physician on call will contact you. Sudden loss of vision in one eye or both, even if it comes back, a curtain or shadow over part of your vision, or a sudden burst of new floaters or flashes of light also need same day care, whatever the cause.
Frequently asked questions about glaucoma
Can glaucoma be cured?
No. Glaucoma is managed for life, and vision lost to it does not come back. Early treatment can often stop the damage and protect the vision you have, which is why finding it early matters.
Does high eye pressure mean I have glaucoma?
Not by itself. High eye pressure without optic nerve damage is called ocular hypertension. Some people with high pressure never develop glaucoma, and some people with glaucoma have normal pressure, because normal pressure varies by person. An exam of the optic nerve and your side vision determines whether glaucoma is present.
Is glaucoma hereditary?
Glaucoma can run in families. A family history of glaucoma is a risk factor named by the National Eye Institute, the Centers for Disease Control and Prevention, and the American Academy of Ophthalmology. A family history does not mean you will develop glaucoma; it means you should be examined and then checked at the interval your physician recommends.
How often should I be checked for glaucoma?
It depends on your age and your risk. The National Eye Institute recommends a comprehensive dilated eye exam every 1 to 2 years for people at higher risk, and it advises everyone to ask their eye doctor how often they need to be checked. Your physician sets your interval at your exam.
Does glaucoma hurt?
Open angle glaucoma, the most common type, causes no pain. Acute angle closure glaucoma does. Severe eye pain with headache, nausea, blurred vision, or halos around lights is an emergency and needs same day care.
Can glaucoma be prevented?
There is no known way to prevent glaucoma. Vision loss from it can be prevented by finding it early at a dilated eye exam and treating it. The Centers for Disease Control and Prevention also notes that healthy habits, such as keeping a healthy weight, controlling blood pressure, staying physically active, and not smoking, help lower the risk of vision loss from glaucoma.
Schedule a glaucoma evaluation in Westerville
Comprehensive EyeCare of Central Ohio was founded in 1975 and serves Westerville, Worthington, Sunbury, Lewis Center, and the greater Columbus area from its Westerville office. Call 614-890-5692 to schedule a comprehensive dilated eye exam, or ask for a glaucoma evaluation if you have a family history of glaucoma, a prior high pressure reading, or any of the risk factors above. You can also contact us online. Office hours are Monday to Friday, 7:00 AM to 4:30 PM, and Saturday, 8:00 AM to 12:00 PM, at 450 Alkyre Run Drive, Suite 100, Westerville, Ohio 43082. Appointment and office information is on our office page.
Keep reading
- Glaucoma treatment in Westerville and Columbus: the services page for glaucoma care at our office.
- Steven H. Suh, MD, Director of Cataract Surgery: the physician who reviewed this page.
- Appointments and office hours: scheduling, what to bring, and the after hours line.
Sources
- National Eye Institute, Glaucoma, last updated August 19, 2026, https://www.nei.nih.gov/eye-health-information/eye-conditions-and-diseases/glaucoma, accessed 10/12/2026.
- National Eye Institute, Types of Glaucoma, last updated December 5, 2024, https://www.nei.nih.gov/eye-health-information/eye-conditions-and-diseases/glaucoma/types-glaucoma, accessed 10/12/2026.
- Centers for Disease Control and Prevention, About Glaucoma, May 15, 2024, https://www.cdc.gov/vision-health/about-eye-disorders/glaucoma.html, accessed 10/12/2026.
- American Academy of Ophthalmology, Primary Open-Angle Glaucoma Preferred Practice Pattern 2025, Highlighted Findings and Recommendations for Care, https://www.aao.org/education/preferred-practice-pattern/primary-open-angle-glaucoma-ppp, accessed 10/12/2026.
- American Academy of Ophthalmology, What Is Chronic Angle-Closure Glaucoma?, reviewed by Anju Goyal, MD, published December 2, 2025, https://www.aao.org/eye-health/diseases/what-is-chronic-angle-closure-glaucoma, accessed 10/12/2026.
