Eye doctors use a variety of tests to detect glaucoma. Even if you don’t have any symptoms, you may want to consider regular screenings if you have certain risk factors.

Glaucoma is a progressive eye disease that can eventually cause permanent vision loss, so early detection and treatment are key.

To receive a diagnosis, you’ll likely see an ophthalmologist, a doctor specializing in eye diseases. In addition to a complete eye exam, they’ll also conduct specific glaucoma tests to check for any signs of the condition.

Commonly, five tests are available that help diagnose glaucoma. Depending on your symptoms, your doctor may prescribe a combination of tests.

Dilated eye exam (ophthalmoscopy)

A dilated eye exam helps view the optic nerve. As the name suggests, this test involves dilating your pupils with specialized eye drops.

During the test, an ophthalmologist will use a magnifying glass with a light to get a better look at the color and shape of your optic nerve. If they see anything unusual, they might follow up with additional testing, such as gonioscopy.


The purpose of a gonioscopy is to examine the angle where your cornea and iris intersect.

Before the test, the doctor will give you numbing eye drops. Then, the ophthalmologist will use a lens to evaluate the angle. Any angle smaller or larger than usual could indicate closed-angle or open-angle glaucoma.


A pachymetry involves using a pachymeter tool to help measure corneal thickness. As with gonioscopy, a doctor will give you numbing eye drops first.

A thin cornea could indicate glaucoma.


Also called a visual field test, a perimetry test examines your total field of vision. This test involves using light in front of your eyes to help “map” your vision on both sides (peripheral vision).

The purpose of perimetry is to see if your field of vision changes over time. For this reason, your care team may recommend perimetry tests once or twice a year.


A tonometry test measures pressure in your eye.

Before the test, the doctor will give you numbing drops. Then, you’ll place your face into a slit lamp, and a tonometer will briefly puff air onto your eyes to measure eye pressure.

A typical tonometry reading is between 12 and 21 millimeters of mercury (mm Hg). A reading higher than 21 mm Hg may indicate glaucoma.

Glaucoma doesn’t always cause noticeable symptoms in its early stages, so testing can help detect it before it progresses to a more advanced stage.

If you already have glaucoma, routine testing can also help to monitor how the disease progresses.

An eye doctor may also recommend glaucoma testing if you’re considered high risk.

Common risk factors for this glaucoma include:

  • Age: Glaucoma is most common in adults over the age of 60 years, with the risk increasing yearly.
  • Genetics: If glaucoma runs in your family, you may have a higher risk of developing it.
  • Race: African Americans over the age of 40 years may be more likely to develop glaucoma.
  • Personal history of eye disease: Doctors consider eye inflammation, retinal detachment, and eye tumors as risk factors for glaucoma development. A history of severe eye injuries can also increase your risk.
  • Certain medical conditions: High blood pressure, heart disease, and diabetes may all increase your risk of developing glaucoma.
  • Certain medications: If you use Immunosuppressants for a long time, it may increase your chances of developing glaucoma.

Glaucoma tests may cause some brief discomfort, but they don’t pose any health risks.

If a test involves pupil dilation, you may experience temporary blurry vision and light sensitivity for up to a day after the exam. While many people find they can drive home after having their eyes dilated, others find it difficult, so you may consider arranging a ride home.

Will I need to do anything to prepare for a glaucoma test?

Glaucoma tests usually don’t require any preparation. If the test involves pupil dilation, you may want to consider arranging a ride home if you experience some temporary blurry vision. But many people can drive themselves home. You may also want to bring sunglasses in case the dilation makes you more sensitive to light.

How long does a glaucoma test take?

Glaucoma testing isn’t a time consuming commitment, with individual tests taking just a few minutes each. Visual field tests may take up to 10 minutes. Dilated eye tests may take a bit longer, as after using, the drops can take up to 30 minutes to have an effect.

How often should I be screened for glaucoma?

African Americans over the age of 40 years and all adults over the age of 60 years should consider getting screened for glaucoma every year. If you have risk factors for this eye condition, such as family history, high blood pressure, or diabetes, your doctor may recommend more frequent screening.

Glaucoma tests are a crucial component of glaucoma diagnosis and disease management. As there’s no cure for this progressive eye disease, treatments are necessary to help prevent complications such as vision loss.

If you are over the age of 60 years or have other risk factors for glaucoma development, consider talking with an eye doctor about testing.