Glaucoma testing combines a handful of specific, painless measurements — eye pressure, optic nerve imaging, peripheral vision mapping, and a check of your eye’s drainage angle — that together catch damage long before you’d notice any change in your sight. At Lucent Family Eye Care, this testing is part of our broader eye disease management program, which also covers diabetic retinopathy, macular degeneration, and cataracts.
Why Glaucoma Is Called “The Silent Thief of Sight”
Glaucoma has earned this nickname for a simple, unsettling reason: the most common form of the disease produces no pain, no redness, and no obvious symptoms until real damage has already occurred. Primary open-angle glaucoma, which accounts for more than 90% of cases, progresses so gradually that peripheral vision disappears in a slow, almost imperceptible creep. By the time many people notice gaps in their side vision, they’ve already lost a meaningful portion of it — which is why some studies suggest up to half of people living with glaucoma don’t know they have it.
This is exactly why routine testing matters more than symptom-watching. Glaucoma doesn’t announce itself. Regular, specific testing is the only reliable way to catch it early.
The Different Types of Glaucoma
Not all glaucoma behaves the same way, and understanding the differences helps explain why your optometrist runs more than one test.
- Primary open-angle glaucoma — the most common form, caused by a gradual clogging of the eye’s drainage angle. It’s painless and slow-moving, which is what makes it so easy to miss.
- Angle-closure glaucoma — can develop slowly, but an acute attack is a genuine medical emergency, with sudden severe eye pain, headache, nausea, blurred vision, and halos around lights. Anyone with these symptoms needs urgent care immediately.
- Normal-tension glaucoma — optic nerve damage that occurs even when eye pressure measures within the normal range, which is part of why pressure alone is never the full picture.
- Secondary glaucoma — triggered by another eye condition, an injury, or certain medications, particularly long-term steroid use.
Who Is Most at Risk
Some people need to take glaucoma screening more seriously than others. Known risk factors include:
- Age 40 and older, with risk climbing further after 60
- A family history of glaucoma
- African, Hispanic/Latino, or Asian heritage, each linked to elevated risk for different glaucoma types
- Diabetes or other systemic health conditions
- Thin corneas
- Elevated eye pressure — the single biggest modifiable risk factor
- High myopia (nearsightedness) or hyperopia (farsightedness)
- A past eye injury
- Prolonged use of steroid medications
If two or more of these apply to you, it’s worth mentioning to your optometrist directly at your next visit.
What Actually Happens During a Glaucoma Work-Up
A proper glaucoma assessment isn’t a single test — it’s a battery of measurements that each answer a different question about your eye health. Here’s what to expect:
- Tonometry measures your intraocular pressure, typically in the range of roughly 10 to 21 mmHg. This is the classic “puff of air” test, though many clinics now use a gentler contact method. It’s worth knowing that glaucoma can still occur at normal pressure readings, which is why this test is never used on its own.
- Optic nerve evaluation, increasingly performed with OCT (optical coherence tomography), measures the thickness of the retinal nerve fiber layer and tracks it over time. Subtle thinning here can flag damage before it ever shows up as a symptom.
- Perimetry, or visual field testing, maps your peripheral vision in detail to detect early functional vision loss — the kind you wouldn’t notice on your own.
- Gonioscopy uses a small hand-held lens to examine the drainage angle inside your eye directly, which is how your optometrist distinguishes open-angle glaucoma from angle-closure glaucoma.
- Pachymetry measures corneal thickness, since thinner corneas affect both glaucoma risk and how your eye pressure readings should be interpreted.
At our Vancouver clinic, this testing battery is supported by Optos Monaco ultra-widefield imaging and OCT scans alongside virtual-reality visual field testing, giving Dr. Yee and Dr. Sultani a detailed, comparable picture of your optic nerve and peripheral vision at every visit — not just a single snapshot.
How Often Should Vancouver Residents Be Screened
For most adults, a comprehensive eye exam every one to two years after age 40 is a reasonable baseline. If you fall into one of the higher-risk categories above — family history, diabetes, an at-risk ethnic background, or age 60 and up — annual testing, or whatever frequency your optometrist recommends, is more appropriate. If you’ve already been diagnosed with or are being monitored for glaucoma, expect follow-up testing every three to six months, or as directed.
Can Glaucoma Be Cured?
Glaucoma is not curable, and any vision already lost to it cannot be reversed with current treatment. But it is highly manageable: with proper treatment and monitoring, only a small minority of glaucoma patients ever experience blindness. Treatment options — eye drops, laser treatment, or surgery in more advanced cases — work by slowing or halting further damage, not by restoring vision. The message worth remembering is simple: you can’t undo damage that’s already occurred, but early detection prevents most of the vision loss that would otherwise happen.
If you’re due for an eye exam, have a family history of glaucoma, or simply haven’t had your eye pressure and optic nerve checked recently, book an appointment with our Vancouver team. You can also read more about how we approach eye disease management across glaucoma and other sight-threatening conditions.
Frequently Asked Questions
Not usually if it’s caught and treated. With proper treatment and ongoing monitoring, only a small percentage of glaucoma patients experience blindness — the key is catching it early, since damage that’s already occurred can’t be reversed, but further progression can typically be slowed or stopped.
No. Glaucoma cannot be cured, and vision already lost to it cannot be restored with current treatment. What treatment can do is slow or halt further damage, which is why ongoing monitoring and early detection matter so much more than trying to reverse existing loss.
Family history is one of the most consistent risk factors identified for glaucoma. If a parent or sibling has been diagnosed, your own risk is higher, and it’s worth mentioning this to your optometrist so they can recommend an appropriate testing schedule for you.
Average-risk adults should have a comprehensive eye exam every one to two years after turning 40. If you have risk factors like family history, diabetes, certain ethnic backgrounds, or you’re over 60, annual testing is generally recommended. Anyone already diagnosed or being monitored typically needs follow-up every three to six months, or as their optometrist directs.
Because the most common form, primary open-angle glaucoma, causes no pain and no early symptoms. Peripheral vision loss happens so gradually that many people don’t notice it until a significant portion is already gone, which is why routine testing — not waiting for symptoms — is the only reliable way to catch it.
Open-angle glaucoma is the more common form, developing slowly and painlessly as the eye’s drainage angle gradually clogs. Angle-closure glaucoma involves a narrower or blocked drainage angle, and an acute attack is a medical emergency with sudden severe eye pain, headache, nausea, blurred vision, and halos around lights that requires immediate care.
Yes. This is known as normal-tension glaucoma, where optic nerve damage occurs even though intraocular pressure measures within the typical range. It’s part of why eye pressure testing alone isn’t enough — a full work-up also includes optic nerve imaging and visual field testing.
A thorough glaucoma assessment generally includes tonometry to measure eye pressure, OCT imaging to evaluate the optic nerve, perimetry (visual field testing) to check peripheral vision, gonioscopy to examine the eye’s drainage angle, and pachymetry to measure corneal thickness. Each test answers a different question, which is why they’re used together rather than on their own.
