Glaucoma: The Silent Thief of Sight — Causes, Symptoms and Treatment
Glaucoma is a group of eye diseases that damage the optic nerve, the cable that carries what you see from your eye to your brain. It's called the silent thief of sight because the most common type has no pain and no early symptoms, so many people don't know they have it until some vision is already gone.
That's the part that keeps me up at night. Glaucoma damage can't be undone. But when we catch it early, treatment can help protect the vision you have. That's why I push so hard for regular eye exams.
What causes glaucoma?
Inside your eye, a clear fluid is always being made and drained. It's not your tears. It nourishes the front of the eye. When the fluid doesn't drain well, pressure inside the eye can rise. Over time, that pressure can harm the optic nerve.
But pressure isn't the whole story. Some people have high eye pressure and never get glaucoma. Others get glaucoma with normal pressure. Blood flow to the optic nerve and the nerve's own sensitivity also seem to matter. That's why an eye doctor looks at the nerve itself, not just a pressure number.
What are the main types of glaucoma?
Open-angle glaucoma
This is the most common type in the United States. The eye's drainage area stays open, but fluid drains too slowly. Pressure can creep up over years. There's no pain. Side vision fades so slowly that the brain fills in the gaps, and people don't notice until damage is advanced.
Angle-closure glaucoma
In this type, the colored part of the eye (the iris) blocks the drainage area. It can happen slowly, or it can happen all at once. A sudden attack is an emergency. It can cause severe eye pain, redness, blurred vision, rainbow halos around lights, headache, nausea and vomiting. If that happens, call us right away or go to the emergency room.
Other types
Normal-tension glaucoma damages the nerve even though pressure stays in the normal range. Secondary glaucoma can follow an eye injury, inflammation, certain medicines or other eye conditions. Babies and young children can also be born with or develop glaucoma, though this is rare.
Who is at higher risk for glaucoma?
Anyone can get glaucoma, but your risk is higher if you:
- Are older. Risk rises with age, especially after 60.
- Have a family history. Having a parent, brother or sister with glaucoma raises your risk.
- Are of African American or Hispanic heritage. Glaucoma tends to occur more often, and sometimes earlier, in these groups.
- Are very nearsighted. High myopia is linked to a higher risk of glaucoma.
- Use steroids. Long-term steroid use, including steroid eye drops, inhalers and pills, can raise eye pressure in some people.
- Have diabetes. Diabetes is linked to a higher risk of some types of glaucoma.
- Have had an eye injury. Past trauma can affect the eye's drainage.
- Have high eye pressure or thin corneas. Both are found during an eye exam.
If any of these fit you, tell your eye doctor. It may change how often we want to see you.
What are the symptoms of glaucoma?
With open-angle glaucoma, there usually are none early on. No pain. No redness. Central vision stays sharp. The first changes are small blind spots in side vision that you won't notice in daily life.
As it progresses, people may bump into things, have trouble seeing at night, or miss things off to the side. By then, damage is already done. This is exactly why we don't wait for symptoms.
How is glaucoma tested?
A glaucoma check is part of a comprehensive eye exam. We look at several things together:
- Eye pressure. We measure the pressure inside your eye. It's quick and painless.
- The optic nerve. We look directly at the nerve at the back of the eye and take retinal images to track it over time.
- OCT imaging. OCT is a scan that uses light to measure the thickness of the nerve fiber layer around the optic nerve. It can pick up thinning before you notice any vision loss. With an in-office telehealth visit, the $39 imaging includes this scan plus a second OCT scan of the macula.
- Visual field test. This maps your side vision. You look at a center point and click a button when you see small lights flash around it.
- The drainage angle and cornea. We may check the angle where fluid drains and measure the thickness of your cornea, which affects pressure readings.
No single test makes the diagnosis. We put the pieces together and often compare results over several visits. Learn more about our glaucoma care and the technology we use.
How is glaucoma treated?
Treatment aims to lower eye pressure to protect the optic nerve from more damage. It can't bring back vision that's already lost, but it can help keep the vision you have.
- Prescription eye drops. These are often the first step. They either lower how much fluid the eye makes or help it drain better. They work only if you use them every day as prescribed.
- Laser treatment. A laser can help fluid drain more easily. For angle-closure, a laser can make a tiny opening in the iris to let fluid flow.
- Surgery. When drops and laser aren't enough, surgeons can create new drainage paths or place tiny devices to help fluid leave the eye.
Glaucoma is lifelong. Treatment means regular checkups, even when you feel fine. If drops cause side effects or are hard to afford, tell us. There's usually another option.
When should you see an eye doctor?
We recommend a comprehensive eye exam once a year, especially if you have any of the risk factors above. Your eye doctor may want to see you more often if you have glaucoma or are a glaucoma suspect. Read more in our post on why your eyes might feel pressure.
Call us right away or go to the emergency room if you have:
- Sudden, severe eye pain with redness
- Halos around lights with nausea or vomiting
- Sudden vision loss or blurry vision
- A curtain or shadow across your vision
- New flashes of light or a sudden shower of floaters
How we do it at Bolt Eye Group
At Bolt Eye Group, every comprehensive exam includes a full eye-health check. For $39, every patient also gets photos of the retina and optic nerve and a map of the cornea. With an in-office telehealth visit, the same $39 also covers two OCT scans, one of the optic nerve and one of the macula. We use them to track changes over time. If you have diabetes, we pay extra attention, and you can learn more on our diabetes eye care page.
We see patients at five offices: Canton, East Cobb/Marietta, Lawrenceville and Riverdale in Georgia, and Johnson City, Tennessee. We accept VSP, EyeMed, Davis Vision, Spectera, Medicare and major medical plans, including Blue Cross Blue Shield, Aetna, UnitedHealthcare, Cigna and Humana. HSA/FSA and CareCredit are welcome.
Frequently asked questions
Can glaucoma be cured?
There's no cure for glaucoma, and vision lost to it can't be restored. But treatment can lower eye pressure and help slow or prevent further damage. Early detection gives you the best chance to keep your sight.
Does glaucoma hurt?
The most common type, open-angle glaucoma, usually causes no pain at all. A sudden angle-closure attack is the exception. It can cause severe pain, redness, halos and nausea. It needs care right away.
Is glaucoma hereditary?
Glaucoma often runs in families. If a parent, brother or sister has it, your risk is higher. Tell your eye doctor about your family history.
How often should I be checked for glaucoma?
We recommend a yearly comprehensive eye exam for most adults. The American Optometric Association recommends at least every two years for low-risk adults under 65 and yearly after that. If you have risk factors or are being watched for glaucoma, your eye doctor may recommend more frequent visits.
Can I have glaucoma with normal eye pressure?
Yes. Normal-tension glaucoma damages the optic nerve even when pressure is in the normal range. That's why we also check the optic nerve, use OCT imaging and test your side vision.
Book an exam at your nearest Bolt Eye Group office
Glaucoma won't announce itself. A yearly exam can catch it. Book an exam at your nearest Bolt Eye Group office in Canton, East Cobb/Marietta, Lawrenceville, Riverdale or Johnson City, TN.