Your risk of glaucoma rises as you get older. Research from the National Institutes of Health, published in 2024, found that 4.2 million Americans have glaucoma, and the condition affects 8 percent of adults over age 80. If you are over 40, regular glaucoma screening gives you a head start on catching changes early.
Glaucoma tends to run in families. If a parent, sibling, or grandparent has been diagnosed, your own risk is higher than average. Specialized testing helps your eye doctor track your numbers over time and watch for the earliest signs of change.
Even if no one in your family has been diagnosed, keep in mind that many cases go undetected. A family member may have had glaucoma without knowing it. Regular screening helps close that gap.
High eye pressure, thin corneas (the clear front surface of your eye), severe nearsightedness, or a history of eye injury can all increase your risk. Certain health conditions like diabetes and high blood pressure also play a role. People of African, Hispanic, or Asian descent face a higher risk as well.
If any of these apply to you, your eye doctor may recommend more frequent testing. Knowing your risk factors helps your doctor decide which tests to include and how often to repeat them.
Think of your eye like a basketball. It needs a certain amount of air pressure to hold its shape. Tonometry measures that internal pressure, called intraocular pressure or IOP. When pressure is too high, it can push against the optic nerve at the back of your eye and cause damage over time.
The test itself takes just a few seconds. Your eye doctor uses a small instrument that gently touches the surface of your eye or sends a quick puff of air. You may feel a light tap, but there is no pain.
Optical coherence tomography, or OCT, is like an ultrasound that uses light instead of sound. It takes a cross-section image of the optic nerve and the thin nerve fiber layer at the back of your eye. This gives your eye doctor a detailed map showing exactly how thick or thin those nerve fibers are.
This matters because glaucoma slowly thins the nerve fiber layer before you notice any vision loss. OCT can measure changes as small as a fraction of a hair's width, making it one of the most sensitive tools for catching glaucoma early.
Glaucoma typically affects your peripheral (side) vision first. A visual field test maps out your entire range of vision by flashing small dots of light in different positions while you look straight ahead. Each time you see a flash, you press a button.
The test creates a chart showing any blind spots or weak areas in your vision. Your eye doctor compares these results over time to see whether your peripheral vision is stable or slowly changing.
The fluid inside your eye, called aqueous humor, drains through a small channel where the iris (the colored part) meets the cornea. This channel is called the drainage angle. Gonioscopy uses a special lens placed gently on your eye to let your doctor see whether that drainage angle is open, narrow, or blocked.
This test helps determine which type of glaucoma you may have, which directly affects your treatment plan.
A normal eye pressure reading typically falls between 10 and 21 millimeters of mercury. A healthy OCT scan shows a thick, even nerve fiber layer. A clean visual field test shows no blind spots or missing areas. When all three results line up, your eye doctor has strong evidence that your optic nerve is healthy.
An elevated pressure reading does not automatically mean you have glaucoma. Some people have naturally higher eye pressure without any nerve damage, a condition called ocular hypertension. On the other hand, some people develop glaucoma even with pressure readings in the normal range. That is why your eye doctor looks at the full picture, combining pressure, nerve imaging, and visual field results together.
A single test gives your eye doctor a snapshot. But the real power of glaucoma testing comes from comparing results over months and years. Small shifts in nerve fiber thickness or subtle changes in your visual field pattern can signal that glaucoma is developing. Even when each individual result still looks close to normal, the trend over time may tell a different story. According to data from the Glaucoma Research Foundation, 50 percent of Americans with glaucoma remain undiagnosed. Consistent, repeated testing during regular eye exams is one of the most reliable ways to change that number.
Modern imaging technology can measure the thickness of the nerve fiber layer around your optic nerve with remarkable precision. These scans are fast, usually taking less than a minute. They create a color-coded map that makes it easy for your eye doctor to spot areas where the nerve fibers are thinning. Each scan is saved so it can be compared to future results.
Today's visual field machines use computer algorithms to track patterns in your results. They can separate normal variation (everyone has a slightly different response each time) from real changes that suggest glaucoma progression. This kind of analysis helps your eye doctor make confident decisions about whether your treatment plan is working or needs adjustment.
There is very little you need to do to prepare. Continue taking any eye drop medications as prescribed. If you wear contact lenses, your eye doctor may ask you to remove them for certain tests. Bring your current eyeglasses and a list of any medications you take.
Most glaucoma tests are painless and take only a few minutes each. Your eye doctor may use numbing drops for tests that involve light contact with your eye. You will sit in a comfortable chair and follow simple instructions like looking straight ahead or pressing a button when you see a flash of light. A complete glaucoma evaluation typically takes about 30 to 45 minutes.
Your eye doctor will walk you through your results and explain what each number and image means for your eyes. If everything looks healthy, you will get a recommended schedule for your next check. If your results show signs of elevated pressure or early nerve changes, your doctor will discuss next steps. These may include more frequent monitoring, eye drop medication, or a referral to a specialist for further evaluation.
Every glaucoma evaluation starts with a thorough eye exam. Your eye doctor checks your eye pressure, examines the optic nerve, and assesses your overall eye health. If anything looks unusual, you move on to the specialized tests.
If your screening raises any concerns, your eye doctor will order a full set of glaucoma tests: OCT imaging, visual field testing, and possibly gonioscopy. These first results become your baseline, the starting point your doctor will use for all future comparisons.
Glaucoma management is a long-term partnership between you and your eye doctor. You will return for periodic testing so your doctor can track your results over time. If treatment is needed, your eye doctor may prescribe pressure-lowering eye drops or refer you to a specialist for additional procedures. At Insight Vision Optometry, Las Vegas, our team works with you at every step to keep your vision stable.
For most adults over 40 with no risk factors, a glaucoma screening every one to two years is a good starting point. If you have a family history of glaucoma, elevated eye pressure, or other risk factors, your eye doctor may recommend annual testing or even more frequent visits. Your doctor will set a schedule based on your individual results.
Yes. That is the entire purpose of these tests. OCT imaging can detect thinning of the nerve fiber layer years before it causes noticeable vision loss. Visual field testing can pick up subtle blind spots that you would not notice in everyday life. Catching these changes early gives your eye doctor the chance to start treatment before significant vision loss occurs.
This is called ocular hypertension. It means your eye pressure is above average, but there is no sign of optic nerve damage yet. Your eye doctor will monitor you more closely with regular testing. In some cases, your doctor may recommend preventive treatment with pressure-lowering drops to reduce your risk of developing glaucoma over time.
Most patients find glaucoma testing very comfortable. The OCT scan is completely non-contact, meaning nothing touches your eye. Tonometry involves either a gentle touch or a brief puff of air. If your eye doctor needs to perform gonioscopy, numbing drops are used first so you feel only light pressure. The visual field test simply asks you to press a button when you see a light flash.
Glaucoma damage to the optic nerve cannot be reversed, but it can be slowed or stopped with treatment. That is what makes early detection so valuable. When glaucoma is caught before significant nerve fiber loss has occurred, treatment can often preserve your remaining vision for the rest of your life. The earlier your eye doctor finds it, the more vision there is to protect. Our eye doctors at Insight Vision Optometry, Las Vegas are here to help patients in Spring Valley and Southwest Las Vegas stay ahead of this condition with regular, thorough testing.
