Dry Eye Treatment

Each time you blink, a thin film of tears spreads across the front of the eye. Its innermost mucin layer helps the tears cling to the surface, the watery middle layer keeps the surface moist, and the outer oily layer slows evaporation. In dry eye one or more of these layers stops working properly. Some people produce too little watery tear fluid. More often, the oil glands along the eyelid margin release too little oil and the tears evaporate within seconds.

Symptoms vary from person to person: burning, stinging, a gritty feeling as if there is sand in the eye, redness, discomfort in bright light, and blurring that comes and goes while reading or looking at a screen. Blurring that clears when you blink suggests the tear film is breaking up quickly.

Who is more likely to get dry eye?

People who spend long hours at a screen, work in air-conditioned or dry rooms, or wear contact lenses are more prone to it. Tear production falls with age, and hormonal changes such as the menopause increase dryness in women. Underlying causes include rheumatic conditions such as Sjögren’s syndrome and rheumatoid arthritis, eyelids that do not close fully, and inflammation of the lid margin (blepharitis). Medications can reduce tears too, including antihistamines, some antidepressants and isotretinoin, which is used for acne. Temporary dryness is also common after laser and eyelid surgery.

Why do my eyes burn after screen work?

We normally blink 15–20 times a minute. When we focus on a screen this drops sharply, and many blinks are incomplete, with the lid reopening before it has fully closed. The tear film breaks up before it is renewed, so burning and tiredness build up by the end of the day.

A few habits reduce the strain:

• Every 20 minutes, look at something about 6 metres (20 feet) away for 20 seconds.
• Position the screen slightly below eye level. Looking down means the lids cover more of the eye.
• Keep air conditioning and car heater vents pointed away from your face, and use a humidifier in dry rooms.
• During long sessions, close your eyes fully and deliberately a few times.

What is meibomian gland dysfunction?

Along the upper and lower lid margins, just behind the lashes, sits a row of small oil glands called meibomian glands. With every blink they release a thin layer of oil over the tear film. When the gland openings become blocked or the oil thickens, this layer thins and the tears evaporate quickly. This is one of the most common causes of dry eye. Red lid margins, crusting at the base of the lashes and burning that is worse in the morning often go with it. Drops alone are not enough here; the blocked glands also need to be opened.

What tests are done at the examination?

The examination starts with questions about when your symptoms are worse, which medicines you take and how long you spend at screens. The lid margins, lashes and eye surface are then examined with a slit lamp, a microscope with a bright light.

• Tear break-up time: An orange dye called fluorescein is put into the eye. After a blink, the doctor times how many seconds pass before the first dry spot appears in the tear film. Under 10 seconds means the tears are breaking up too quickly.
• Schirmer test: A thin paper strip is placed on the lower lid. The length that becomes wet in five minutes shows how much watery tear fluid the eye produces.
• Surface staining: Fluorescein or lissamine green dye shows damage that dryness has caused to the cornea and the conjunctiva (the thin membrane covering the white of the eye).
• Meibomian gland assessment: Gentle pressure on the lid margin shows whether the gland secretion is clear oil or a thick, paste-like substance. If needed, the glands are imaged with infrared light (meibography).

These results show which layer of the tear film is failing, and treatment is chosen accordingly.

How is dry eye treated?

Most patients use more than one approach, and the plan is adjusted at follow-up visits.

Choosing artificial tears

Artificial tears temporarily replace missing tear fluid. Three things guide the choice:

• Preservatives: If you need drops more than four times a day, preservative-free single-dose vials or preservative-free multi-dose bottles are used. Preservatives can irritate the eye’s surface with frequent use.
• Thickness: Thin drops do not blur vision, so they suit daytime use. Gels and ointments keep the eye moist for longer but blur vision for a few minutes, so they are mostly used at bedtime.
• Ingredients: Drops containing lipids may suit patients with a weak oily layer, that is, those with meibomian gland problems.

Lid hygiene and warm compresses

A warm compress held on the closed lids for 5–10 minutes softens the thickened oil in the glands. This is followed by a gentle massage towards the lash line with a fingertip, then cleaning of the lid margin with a lid-cleansing solution or wipe. The compress should never be hot enough to burn the skin. The effect builds gradually with daily use, and symptoms often come back if the routine stops.

Anti-inflammatory drops

The longer dryness lasts, the more chronic inflammation develops on the eye’s surface, and that inflammation disrupts tear production further. Prescription drops such as ciclosporin or lifitegrast aim to break this cycle. They work gradually and can sting when you first start them.

Punctal plugs

The puncta are the tiny openings at the inner corner of the upper and lower lids, through which tears drain into the nose. A small silicone plug, or a collagen plug that dissolves over time, placed in this opening keeps tears on the eye for longer. Plugs help most when the eye produces too little watery tear fluid. A plug can fall out on its own, irritate the inner corner or cause watering, and it can be removed if needed. Any active inflammation of the lid margin is treated first, because a plug would also hold inflamed tears on the eye.

IPL and thermal pulsation

Intense pulsed light (IPL) can be used for meibomian gland dysfunction. The eyes are covered with protective shields and light pulses are applied to the skin of the lower lids and cheeks. The aim is to calm inflammation along the lid margin and help the glands release their oil, and treatment is planned as a series of sessions a few weeks apart. Thermal pulsation devices, which warm the lids from the inside while applying controlled pressure to the glands, are used for the same purpose.

Dry eye before and after laser eye surgery

If you are planning laser eye surgery, dry eye is treated first for two reasons. An irregular tear film distorts measurements such as corneal topography and can affect the calculated correction. Dryness that is present before surgery also tends to get worse afterwards.

In LASIK, some of the sensory nerves at the surface are cut when the thin corneal flap is created. These nerves trigger blinking and tear secretion, so dryness is common after surgery and usually settles gradually. SMILE uses a smaller incision, so fewer nerves are affected. At the laser assessment, tear tests are reviewed together with topography and corneal thickness, and if there is significant dryness, the measurements are repeated once it has been treated. Assoc. Prof. Dr. Elif Ceren Yeşilkaya decides which method is suitable based on these results.

When should you seek help straight away?

Dry eye symptoms usually develop slowly. Severe or worsening eye pain, sudden loss of vision, marked redness, being unable to tolerate light, or a pus-like discharge should not be put down to dryness. These can signal a corneal infection or another condition that needs urgent treatment. If you wear contact lenses, take them out and have your eyes examined the same day.

Dry eye assessments take place at the eye clinic of Medicana Zincirlikuyu (Şişli, Istanbul). Bring the boxes of any drops you use and a list of your regular medicines. You may be asked not to use drops for a few hours before the appointment so that the tests give accurate results; you will be told this when you book.