Understand dry eye
Dry eye disease, explained simply.
Know the basics before you book. Understanding what is going on, and what can be done about it, helps you choose the right clinic and the right treatment.
What is dry eye?
Dry eye disease happens when your tears can no longer keep the surface of your eye comfortable and stable. Sometimes that's because you aren't making enough tears; far more often it's because the tears you make evaporate too quickly, usually because of blocked oil glands in the eyelids.
The result is a surface that's irritated and inflamed: gritty, burning, tired eyes, fluctuating vision, and, confusingly, often watery eyes, as the eye over-produces reflex tears to compensate.
The two main types
Two ways a tear film fails.
Dry eye is not one condition. In most people the tears evaporate faster than they can be replaced. In others there was never enough tear volume to begin with. The difference matters, because the treatments are not the same.
Many people have a mix of both, and the balance can shift over time. A proper assessment works out which is dominant — that is what decides the treatment.
Check your symptoms in a minute Evaporative vs aqueous, explained
How it's diagnosed
A real workup looks past “a bit dry”.
A dedicated dry eye assessment goes well beyond being told your eyes look a bit dry. Expect some combination of the following, and expect to be shown the results rather than just told them.
- Meibography — imaging the oil glands inside the eyelids to see how many are still intact.
- Tear break-up time — how long the tear film stays stable between blinks. That's the test in the figure alongside.
- Osmolarity — how concentrated the tears are, which tends to rise as the film destabilises.
- Tear volume — tear meniscus height (imaging the thin strip of tear fluid sitting along the lower lid) and the Schirmer’s strip test give a measure of how much tear fluid you actually produce. That's what separates aqueous-deficient dry eye — including the Sjögren’s-related kind — from the evaporative form.
- Lid-margin examination — the state of the lid edges, the gland openings, and the quality of the oil that can be expressed.
- A symptom questionnaire — a standardised score so change can be measured, not guessed at.
Taken together these separate a true dry eye clinic from a general eye test, and they're what a treatment plan should be built on.
Tear break-up time (TBUT). A trace of fluorescein dye is put in the eye and the tear film is viewed under cobalt-blue light, which makes the dye glow green. You blink once, then hold your eyes open. The dark streaks spreading through the green are where the film has broken and the surface underneath is exposed.
As a rough guide, break-up within about ten seconds points to an unstable tear film — but it is read alongside the rest of the workup, not on its own. This animation is an illustration of the test, not a clinical photograph.
Meibography
Watching the glands disappear.
Meibography is the one test that shows you the tissue itself, rather than a number describing it. Gland loss is gradual and usually quiet early on — glands shorten and thin well before symptoms get loud — and once a gland has gone it generally doesn't come back. What can and can't recover is worth reading before you assume there's time to wait.
Not every practice has this imaging. A dedicated dry eye clinic will usually have a meibographer and use it as standard; a routine eye test usually doesn't include one. It's worth asking before you book, because you can't manage what nobody has looked at.
Meibography. An infrared camera photographs the meibomian glands through the everted eyelid. The glands show up as bright, finger-like stripes running out of the lid margin across the darker tarsal plate, so a clinician can count how much gland tissue is still there rather than infer it.
Moving the bar walks through a simulated progression: glands shorten from their deep ends with ragged, fragmenting tips, some ducts widen near the margin, and glands drop out one at a time until the survivors are stubs. It is an illustration of the pattern that is looked for — not a clinical image, and not a prediction of how fast this happens for any individual.
Root causes
Where dry eye actually starts.
Symptoms show up on the surface of the eye, but that's rarely where the problem begins. Three drivers come up again and again: inflammation, how you blink, and, for some people, eye surgery.
01
Inflammation is the engine
Most people with dry eye have some degree of inflammation on the ocular surface. It's easy to miss, because lubricating drops make the symptoms recede while the inflammation carries on underneath. That's a large part of why untreated dry eye tends to get worse over time rather than settle by itself.
Inflammation usually begins at the eyelids and lid margins, then spreads across the rest of the ocular surface. From there it does two things at once: it damages the surface, and it blocks the meibomian glands that are supposed to stop your tears evaporating.
- Step 1Lid inflammation
- Step 2Ocular surface inflammation
- Step 3Surface damage + blocked oil glands
- Step 4Unstable tear film
- Step 5More inflammation
A vicious cycle. An unstable film irritates the surface, which produces more inflammation, which feeds straight back into step one. Left alone, the loop tightens — which is why treating the driver matters more than topping up the symptom.
What sets that inflammation off
Inflammatory skin disease
Rosacea and other inflammatory skin conditions don't stop at the cheeks. Your lid margins are skin too, and ocular rosacea is a well-recognised driver of meibomian gland disease.
How rosacea and dry eye connectYour inflammatory baseline
Diet, sleep, alcohol, smoking and general inflammatory load all influence how inflamed the ocular surface runs. None of it's a treatment on its own, but it changes the baseline any treatment has to work from.
Harsh or extreme conditions
Air conditioning, heating, wind, dust, low humidity, long flights and smoke all strip the film faster than it can be replaced. A surface that's repeatedly dried out tends to stay irritated.
02
Exposure and blinking
Every blink resurfaces the eye and pushes a fresh layer of oil across the film. Blink less often, or only halfway, and parts of the surface stay exposed between blinks and dry out faster than they should.
Screens are the classic driver: concentrating on a screen reliably slows your blink rate and increases the share of blinks that never fully close. Reading, driving and anything else that holds your attention does the same thing to a lesser degree. It's also one of the few parts of dry eye you can influence directly, which is why blink training turns up in a lot of treatment plans.
03
Surgery, and what it exposes
Cataract surgery and refractive (laser) surgery can both trigger dry eye, largely because the procedures interrupt corneal nerves involved in regulating tears. For most people that settles as the nerves recover.
The more common story is that surgery makes existing dry eye worse. Dry eye that was never picked up beforehand tends to get blamed on the operation afterwards, when it was already there. If you're considering either procedure, having your tear film assessed first is worth the appointment.
This is why assessment-first care matters. Lubricating drops treat the symptom. Working out what is driving the inflammation — and treating that — is what changes the direction things are heading in.
Treatments
The dry eye treatment menu.
Ask most people what dry eye treatment looks like and they'll say eye drops. That's the most common mistake, and it's why so many people manage this condition for years without it ever improving.
Drops ease symptoms. Effective treatment also goes after what is causing them — in most cases inflammation, and the blocked oil glands downstream of it. That's why the menu below goes a long way past drops.
The common mistake
Treating dry eye with lubricating drops alone. Drops are genuinely useful, and for mild cases they may be most of what you need — but on their own they don't address inflammation or gland blockage, so the condition underneath carries on unchanged.
IPL (Intense Pulsed Light)
Pulses of light applied to the cheeks and lids to calm inflammation and improve oil-gland function. Usually a short course of sessions.
Thermal pulsation (LipiFlow-style)
Gentle heat and pressure applied to the eyelids to clear blocked meibomian (oil) glands in a single in-clinic treatment.
Meibomian gland expression
Manual clearing of the oil glands along the lid margin, often paired with heat, to restore a healthier tear film.
Punctal plugs
Tiny inserts that slow tear drainage so your own tears stay on the eye longer. Reversible and quick to fit.
Scleral lenses
Large, fluid-filled contact lenses that bathe the eye surface: used for severe or stubborn dry eye.
Autologous serum drops
Eye drops made from your own blood serum, used for severe ocular surface disease when standard drops fall short.
Blepharitis & lid care
Structured lid-hygiene programs to control the bacteria and inflammation that drive lid-margin disease.
Prescription dry eye drops
Anti-inflammatory or immune-modulating drops (such as ciclosporin) prescribed for moderate to severe dry eye.
Common questions
Dry eye FAQ
For most people dry eye is managed rather than cured. But with the right treatment plan it can be controlled so well that day-to-day symptoms largely disappear. The key is matching the treatment to the cause.
Many dry eye clinics are optometry-led and handle the large majority of cases. Severe, complex or surgical cases are usually referred to an ophthalmologist. Both appear in this directory.
Lubricating drops ease symptoms but rarely treat the underlying cause. If you're reaching for drops constantly, that's a strong sign to get a proper dry eye assessment.
Costs vary by clinic and by how many sessions you need. Ask each clinic for a treatment plan and a total estimate up front. Pricing is one of the questions worth comparing.