Glaucoma

What is glaucoma — and who should skip this page?

Glaucoma damages the optic nerve that carries vision to the brain. Eye pressure is a major risk factor, but some people develop glaucoma with pressure in the statistically normal range (normal-tension glaucoma). Skip this page and seek emergency care if you have sudden severe eye pain, headache, nausea, rainbow halos and blurred vision in one eye — that pattern can be acute angle-closure, not a leisurely read.

Open-angle glaucoma is slow and usually painless. People often notice it only when side vision is already reduced, or when an optometrist finds a suspicious nerve or field. That is why regular tests matter more than waiting for a symptom.

We do not publish a single global “success rate” for drops or surgery. Published figures vary by disease type, how late it is found, and how “success” is defined. Lost nerve fibres do not grow back.

Ocular hypertensionUsing glaucoma drops

References for this section: NHS — Glaucoma ↗National Eye Institute - Glaucoma ↗

How do open-angle and angle-closure glaucoma differ?

The names describe the drainage angle where fluid leaves the eye. In primary open-angle glaucoma the angle looks open but drainage is inefficient over years. In angle-closure the iris crowds or blocks that drain, so pressure can rise fast.

East Asian heritage raises angle-closure risk; African-Caribbean and Hispanic heritage raises open-angle risk. Family history matters for both. These are risk markers, not a diagnosis.

References for this section: NHS — Glaucoma ↗National Eye Institute - Glaucoma ↗

Who is at higher risk — and what tests actually happen?

Risk rises with age over 40, a first-degree relative with glaucoma, high eye pressure, short-sightedness for open-angle types, long-sightedness for angle-closure types, diabetes, long-term steroid use, and previous eye injury. Adults should have regular eye tests that can include pressure, optic-nerve assessment and visual fields when indicated.

Diagnosis is not one high pressure reading. Clinicians repeat pressure, look at the nerve (often with OCT), map the visual field, and may use gonioscopy to see the drainage angle. One isolated number does not equal glaucoma.

If you take steroid tablets, inhalers, creams around the eyes or steroid drops, say so. Steroids can raise pressure in susceptible people.

• Tonometry — measures eye pressure
• Optic nerve examination, often with OCT imaging
• Visual field test — maps side vision
• Gonioscopy — inspects the drainage angle
• Pachymetry — corneal thickness can change how pressure is interpreted

References for this section: NHS — Glaucoma ↗National Eye Institute - Glaucoma ↗

What treatments exist — and who should not expect a cure?

Treatment lowers pressure to slow further damage. It does not reverse existing field loss. Most people start with daily drops. Selective laser trabeculoplasty (SLT) can improve drainage in open-angle disease. Laser iridotomy is used when the angle is at risk of closing. Surgery (trabeculectomy or MIGS devices) is for when drops and laser are not enough.

Missed drops allow pressure spikes. If a drop stings, blurs, or changes breathing or heart rate, tell the prescriber — alternatives exist. Do not stop a drop because an internet list ranked it ‘mild’.

Tell every doctor and anaesthetist you use glaucoma medicines. Some drugs interact with eye pressure or with surgery plans.

Glaucoma treatment pathwayGlaucoma laser surgery

References for this section: NHS — Glaucoma ↗National Eye Institute - Glaucoma ↗

Can I drive and work with glaucoma?

Driving depends on the legal visual standard where you live — including visual fields, not only the letter chart. In the UK, glaucoma field loss can mean you must notify the licensing agency even if you still read the number plate. We do not list every country’s rule; ask your clinic and the local licensing body.

Night driving and crowded visual tasks get harder when side vision shrinks. That is a safety verdict, not a moral one. Occupational driving and work at heights may have extra rules.

When is glaucoma an emergency?

Acute angle-closure is an emergency: severe pain, headache, nausea or vomiting, halos, a red eye and sudden blur. Same-day care also matters for sudden vision loss, a dark curtain, or a painful red eye after surgery. Open-angle glaucoma itself is not an excuse to ignore those patterns.

What does sudden vision loss mean?Red eyeSupport cataract charity (optional donate)