Dry eye

Dry eye is not simply a lack of tears. The tear film has three layers, and one of them is a thin oily layer produced by glands on the edge of the eyelids. When these glands do not work well, tears evaporate too quickly and the surface of the eye is left unprotected, even though there are enough tears in terms of quantity.

That is exactly why the most misleading sign is watering. Irritation of the dry surface triggers a reflex wave of tears that are watery and do not stay put, so the eyes water and are dry at the same time.

How it shows

The most common descriptions are a gritty feeling or a feeling of something under the eyelid, burning, redness, heavy and tired eyes, and sensitivity to light. The eyelids are stuck together in the morning, and during the day it is often worst in the evening.

Fluctuating vision is typical. While reading or looking at a screen, the image becomes blurred, but clears after a few firm blinks. This varies over the day and is different from the constant blurring caused by needing glasses.

In contact lens wearers, dry eye often shows as a shorter time that the lenses can be tolerated. A lens that used to be comfortable until the evening starts to bother you in the afternoon.

What makes it worse

Screens are among the most common culprits. During focused concentration, blinking becomes much less frequent and blinks become incomplete, so the tear film is not renewed. The same applies to driving and reading.

Next come dry air in heated rooms, air conditioning, the stream from the vents in a car, wind, smoke and dusty environments. Inflammation of the eyelid margins and long-term contact lens wear also contribute.

It becomes more common with age, in women especially after the menopause. Among diseases, Sjögren's syndrome is important, in which the mouth is also dry.

Dry eye can also be caused by medicines: antihistamines, certain antidepressants, diuretics, isotretinoin and eye drops containing beta blockers. If the problem appeared after starting a new medicine, mention it at the examination.

When it is not dry eye

If a chemical splashes into your eye, rinse it immediately and thoroughly with water for at least fifteen minutes, and only then seek emergency help. With chemical burns, rinsing is more important than getting there quickly.

Also seek emergency eye care for sudden loss of vision, severe eye pain with redness, vomiting and halos around lights, an eye injury, or a sudden appearance of flashes with many floaters or a shadow across part of your field of vision. If sudden loss of vision comes with weakness on one side of the body or difficulty speaking, call 112.

Be especially careful if you wear contact lenses. Pain, marked sensitivity to light and redness with blurred vision can mean an infection of the cornea, which needs to be seen the same day. Remove the lens immediately and do not put it back in.

A markedly red eye on one side with a pus-like discharge and poorer vision is not dry eye either.

What the examination involves

At the ophthalmology clinic, the examination begins with a conversation about your symptoms, screen work, contact lenses, medicines and conditions that can affect the eyes.

This is followed by an examination of the front of the eye, in which the specialist assesses the tear film, the eyelid margins and the openings of the oil glands, and, with the help of a dye, also the state of the surface of the cornea and conjunctiva. Visual acuity and eye pressure are measured.

The aim is to distinguish between dry eye caused by too little tear production and dry eye caused by tears evaporating too quickly, as the treatment differs. It is also checked whether an allergy, inflammation or something else lies behind the symptoms.

If the pupils need to be dilated to examine the back of the eye, your vision will be blurred for a few hours, so do not plan to drive that day.

What helps

Artificial tears are the basis. For occasional use, ordinary ones are enough, but for use several times a day, preservative-free drops are more suitable, as the preservative itself irritates the surface of the eye when applied often. Thicker preparations and gels last longer and are useful in the evening.

For problems with the oil glands, warm compresses on the closed eyelids followed by gentle massage and cleaning of the eyelid margins are key. This is not an add-on but the main measure, and it only works after a few weeks of regular use.

For screen work, regular breaks, consciously blinking fully, having the screen below eye level and turning vents away from your face all help.

When this is not enough, there are prescription medicines that calm inflammation on the surface of the eye, and procedures that keep tears in the eye. Dry eye is usually managed rather than cured once and for all, but with regular measures most people reach the point where they hardly notice any symptoms.