Could This Be Glaucoma?

Glaucoma is one of the most feared eye diagnoses — and for good reason. It's the leading cause of irreversible blindness worldwide. But here's what many people don't realize: with early detection and treatment, most people with glaucoma keep useful vision for their entire lives. The challenge is that glaucoma typically has no symptoms until significant damage has occurred, which is why screening and awareness are so critical. This guide explains the disease, who's at risk, how it's found, and what treatment looks like.

What Is Glaucoma?

Glaucoma is a group of diseases that damage the optic nerve — the cable that carries visual signals from your eye to your brain. In most forms, this damage is related to elevated pressure inside the eye (intraocular pressure or IOP), though it can occur at any pressure level.

The optic nerve has about 1.2 million nerve fibers. Glaucoma kills these fibers gradually, starting with those responsible for peripheral (side) vision. By the time you notice a change, significant damage has already occurred.

Types of Glaucoma

Primary Open-Angle Glaucoma (POAG)

• The most common type (90% of cases)
• Develops slowly over years
• No symptoms until advanced
• The drainage angle of the eye is open but not functioning efficiently

Acute Angle-Closure Glaucoma

• A medical emergency
• Occurs when the drainage angle suddenly closes
• Causes severe eye pain, headache, nausea, blurred vision, and halos around lights
• Requires immediate treatment to prevent permanent damage

Normal-Tension Glaucoma

• Optic nerve damage occurs despite eye pressure being in the "normal" range (below 21 mmHg)
• More common in people of Japanese descent
• May involve poor blood flow to the optic nerve

Secondary Glaucoma

• Caused by other conditions: eye trauma, inflammation, steroid use, advanced cataracts, or abnormal blood vessel growth (neovascular glaucoma)
• Treatment addresses both the glaucoma and the underlying cause

Am I at Risk?

Major Risk Factors

• Age: Risk increases significantly after age 60 (after 40 for African Americans)
• Race/ethnicity: African Americans have 6-8x higher risk; Hispanic/Latino populations also at elevated risk
• Family history: Having a parent or sibling with glaucoma increases your risk 4-9x
• Elevated eye pressure: The higher the pressure, the greater the risk
• High myopia (nearsightedness): Eyes with high myopia are more susceptible
• Thin corneas: Central corneal thickness below average is an independent risk factor
• Diabetes: Increases risk for several types of glaucoma
• Steroid use: Long-term corticosteroid use (eye drops, oral, inhaled) can raise eye pressure

Who Should Be Screened

Based on these risk factors, screening recommendations include:

Population	When to Start Screening
General population	Baseline exam at age 40
African Americans	Age 35-40
Family history of glaucoma	Age 35-40
Diabetes	At diagnosis, then annually
High myopia	Begin in young adulthood
Steroid users	Within weeks of starting steroids

How Glaucoma Is Detected

Glaucoma is diagnosed through a combination of tests — no single test is sufficient.

Eye Pressure Measurement

Tonometry measures the pressure inside your eye:

• Normal range: 10-21 mmHg (but "normal" pressure doesn't rule out glaucoma)
• Methods: Air-puff tonometer (screening), Goldmann applanation (gold standard), handheld devices
• Important: Eye pressure fluctuates throughout the day; a single reading is just a snapshot

Optic Nerve Evaluation

Your doctor examines the optic nerve head (disc) for signs of glaucoma damage:

• Increased "cupping" — the cup-to-disc ratio enlarges as nerve fibers are lost
• Asymmetry between the two eyes
• Notching or thinning of the nerve fiber rim
• Hemorrhage on the disc surface

Optical Coherence Tomography (OCT)

OCT is a high-resolution imaging technology that measures the thickness of the nerve fiber layer surrounding the optic nerve:

• Can detect thinning before it's visible to the naked eye
• Provides objective, reproducible measurements for tracking over time
• Color-coded maps compare your measurements to a normative database
• One of the most valuable tools for early detection and monitoring

Visual Field Testing

The visual field test maps your peripheral vision to detect areas of loss:

• You look at a central fixation point and press a button when you see flashing lights in your peripheral vision
• Takes about 5-10 minutes per eye
• Glaucoma typically causes specific patterns of visual field loss
• Serial testing over time shows whether the condition is stable or progressing

Gonioscopy

Gonioscopy examines the drainage angle of the eye:

• A special lens is placed on the eye to view the angle directly
• Determines whether you have open-angle or angle-closure anatomy
• Helps guide treatment decisions
• Essential for classifying the type of glaucoma

Treatment Options

The goal of all glaucoma treatment is the same: lower eye pressure to a level that prevents further optic nerve damage. Even in normal-tension glaucoma, lowering pressure slows or stops progression.

Eye Drops

Medicated eye drops are usually the first-line treatment:

• Prostaglandin analogs (latanoprost, Vyzulta/latanoprostene bunod) — increase fluid outflow; once-daily dosing; most commonly prescribed first
• Beta-blockers (timolol) — reduce fluid production; used morning and/or evening
• Alpha agonists (brimonidine) — reduce production and increase outflow
• Carbonic anhydrase inhibitors (dorzolamide, brinzolamide) — reduce fluid production
• Rho kinase inhibitors (netarsudil) — newer class; improves outflow through the drainage pathway

Key points about eye drops:

• Consistency is critical — missing doses lets pressure rise and damage continue
• Side effects vary by class (redness, stinging, darkening of iris color, eyelash growth, breathing issues with beta-blockers)
• Technique matters — close your eye for 2 minutes after applying to reduce systemic absorption
• Multiple drops may be needed to achieve target pressure

Laser Treatment

Selective Laser Trabeculoplasty (SLT)

• A quick, in-office laser procedure applied to the drainage angle
• Takes 5-10 minutes; painless or mildly uncomfortable
• Can lower eye pressure by 20-30%
• Effect may last 3-5 years and can be repeated
• Increasingly used as first-line treatment (instead of or alongside drops)
• No daily medication burden

Laser Peripheral Iridotomy (LPI)

• Used for angle-closure glaucoma or narrow angles
• Creates a tiny opening in the iris to improve fluid drainage
• Preventive in people with narrow angles who haven't yet had an acute attack
• Quick and usually definitive

Surgery

When drops and laser aren't sufficient, surgical options include:

Trabeculectomy

• Creates a new drainage pathway for fluid to leave the eye
• Most established glaucoma surgery
• Requires careful postoperative monitoring
• Very effective at lowering pressure

Glaucoma Drainage Devices (Tubes)

• An implanted shunt drains fluid to a reservoir on the eye surface
• Used when trabeculectomy has failed or isn't suitable
• Various designs available (Ahmed, Baerveldt)

Minimally Invasive Glaucoma Surgery (MIGS)

• Newer procedures with faster recovery and fewer risks
• Often combined with cataract surgery
• Includes iStent, Hydrus, goniotomy, and others
• Generally for mild-to-moderate glaucoma

Living with Glaucoma

What to Expect After Diagnosis

• Regular monitoring visits (typically every 3-6 months)
• Periodic OCT scans and visual field tests to track stability
• Adjustments to treatment if pressure isn't at target or damage progresses
• A long-term relationship with your ophthalmologist

Daily Management Tips

• Use eye drops at the same time every day — set alarms or pair with a routine activity
• Store drops where you'll see them (bedside table, bathroom counter)
• Keep a refill calendar so you don't run out
• Bring all your eye medications to every appointment
• Tell any new doctor about your glaucoma before receiving steroids

Protecting Your Remaining Vision

• Attend every follow-up appointment, even when you feel fine
• Report any changes in vision promptly
• Wear UV-protective sunglasses
• Exercise regularly — moderate aerobic exercise may help lower eye pressure
• Avoid head-down positions for prolonged periods (certain yoga inversions, for example)

Frequently Asked Questions

Can I feel my eye pressure rising?

No — with the exception of acute angle-closure glaucoma, elevated eye pressure causes no pain, redness, or sensation. That's why it's called "the silent thief of sight." You cannot detect chronic open-angle glaucoma without a professional eye exam.

If I have high eye pressure, do I definitely have glaucoma?

Not necessarily. "Ocular hypertension" means your eye pressure is above average but there's no optic nerve damage. Your doctor may monitor you closely or start preventive treatment depending on your overall risk level.

Can glaucoma be cured?

There is no cure for glaucoma, and vision loss from glaucoma is permanent. However, treatment is highly effective at preventing further loss. Most people diagnosed and treated early maintain functional vision for life.

Will I go blind from glaucoma?

With modern treatment, most glaucoma patients do not go blind. The key is early detection and consistent treatment. People who lose significant vision to glaucoma are typically those diagnosed late or who don't adhere to treatment.

Is glaucoma hereditary?

Yes, family history is one of the strongest risk factors. If a parent or sibling has glaucoma, your risk is 4-9 times higher. This makes early screening especially important for family members of glaucoma patients.

Can marijuana treat glaucoma?

While marijuana can temporarily lower eye pressure, the effect lasts only 3-4 hours and requires constant use. The side effects (impaired function, cardiovascular effects) far outweigh any benefit. Prescription eye drops and laser treatment are far more effective and practical.

Does glaucoma affect both eyes?

Usually, yes — though the severity may differ between eyes. Treatment is tailored to each eye individually based on pressure, nerve appearance, and visual field results.

How often do I need to see my doctor if I have glaucoma?

Typically every 3-6 months for pressure checks, with OCT and visual field testing performed 1-2 times per year. Your doctor will adjust the frequency based on stability and risk level.

References