Dry eye
Dry eye
What is dry eye?
Dry eye is a common but multifactorial condition that occurs when your tears aren’t able to provide adequate lubrication for your
eyes
, due to a reduction in the quality or quantity of tears. This tear film comprises three layers that work together to keep your eyes moist and protected. The top oily layer helps to prevent evaporation of tears. The middle, watery layer is the thickest layer and the sticky bottom layer helps the tear film to adhere to the eye. If anything upsets the balance of these tear film components it can become unstable or evaporate. This results in dryness and inflammation of the cornea (front of the eye).
Who gets dry eye?
Dry eye can and does affect anyone, but is more common as we get older because we produce a smaller volume of tears.
Some medications can trigger dry eye, as can some general health conditions. External factors such as air-conditioned environments may also exacerbate dry eye symptoms.
There is no cure for dry eye, with treatments options focused on managing symptoms.
Symptoms of dry eye
The symptoms of dry eye syndrome include:
red, scratchy, sore, or itchy eyes
burning or stinging sensations
a feeling of having something in your eyes
crusty eyes (excessive ‘sleep’ in the eye)
blurred vision that changes after a blink
eyes feel ‘heavy’, tired or fatigued
watery eyes (this may seem counter-intuitive but if the surface of the eye dries out completely you may have ‘reflex’ tearing resulting in watery eyes)
difficulty wearing contact lenses comfortably
sensitivity to light.
Causes of dry eye
Some of the factors that cause or contribute to dry eye include:
ageing - tear production slows with advancing age
menopause
medical conditions - such as
arthritis
medication - including
oral contraceptives
,
antidepressants
, antihistamines, diuretics and beta-blockers
climatic conditions - such as dry air and wind
irritants
- such as cigarette smoke, dust or chemical exposure
any trauma to the eye (including burns)
infrequent or incomplete blinking
long periods of screen time
laser surgery
cataract surgery
.
Complications of untreated dry eye syndrome
Complications of untreated dry eye can include:
eye discomfort, which for some may be quite debilitating
fluctuations in vision
damage to the front surface of the eye (the cornea) - in extreme cases can lead to permanent scarring.
Diagnosis of dry eye
Dry eye is diagnosed through tests, including:
examination of the eye surface under a specially designed microscope (a ‘slit lamp biomicroscope’) by optometrist or ophthalmologist.
putting a drop of sodium fluorescein (a yellow dye) into the eyes to evaluate the tear film.
strips of filter paper placed between the lower lid and eye to measure tear production.
Treatment for dry eye
There is no cure for dry eye, but the condition can be successfully managed. Treatment may aim to increase tear production, maintain tear film volume or prevent excess loss of tears.
A range of options may be used, including:
using eye drops, gels or ointments to lubricate the surface of your eyes (these are sometimes called ‘artificial tears’).
special plugs can be inserted into the tear ducts to prevent excessive loss of tears.
in-office device-assisted therapies that improve function of oil producing glands in eye lids
prescription oral medications.
Inflammation of the eyelids (blepharitis)
Some people with dry eyes can experience inflammation of the eyelids (also known as blepharitis).
Bacteria that normally live harmlessly on the skin can cause an infection of the eyelid margins. The result is crusting on the lashes or lid margins (particularly upon waking) and an itchy sensation.
If left untreated, blepharitis can stimulate inflammation, causing the eyelids to become red, swollen and irritated. The inflammation can often disrupt normal tear production causing dry eye.
Treatment for blepharitis
Although low-grade blepharitis is often a chronic condition, most cases respond well to appropriate management. Treatments include:
Cleaning around eyelid margins with a cotton bud or clean face cloth and eyelid scrub.
Eye drops (artificial tears) for dry eyes.
Antibiotic ointments and medications prescribed by your doctor.
Where to get help
Your
GP (doctor)
Optometrist
Ophthalmologist