What causes dry eye syndrome?
There are a number of potential reasons for your dry eyes, which may include
Aging – Dry eyes occur as a part of the natural aging process, especially after the menopause.
Medications – can reduce your lacrimal gland secretions:
- some varieties of antihistamines and decongestants
- certain antidepressants
- some blood pressure drugs (including diuretics)
- medications for Parkinson’s disease
- contraceptive pills
- opiate-based pain relief (such as morphine)
- isotretinoin-type drugs.
Laser eye surgery (LASIK) – Some people who have had certain types of laser eye surgery find they have dry eyes in the weeks after surgery. This is usually a result of damage to the corneal nerves. The nerves usually regenerate and dryness typically improves. Occasionally, it can cause permanent problems, so it is thus recommended that individuals with significant dry eyes should not undergo LASIK treatment.
Other medical conditions- Sjogren’s syndrome, Sacroidosis- can cause inflammation or destruction of the lacrimal gland, resulting in impaired aqueous production. Other conditions, such as ocular cicatricial pemphigoid or Stevens-Johnson syndrome can cause conjunctival scarring, which causes dry eyes by blocking the lacrimal gland ducts. Conjunctival scarring can also occur as a result of chemical burns.
Blepharitis (a condition that causes inflammation of the eyelids) and other such conditions may cause meibomian gland dysfunction, which impairs the secretion of the other components of tears (lipid and mucous), making the eyes dry.
Lagophthalmos- Neurological problems, including stroke and Bell’s palsy, can affect your ability to blink/close your eyelids. This prevents the spread of tears over the eye and allows excessive tear evaporation.
How is dry eye syndrome diagnosed?
Dr Shah will examine your eyes using a slit lamp. A slit lamp can help to see whether:
- the tear meniscus on the lower lid margin is reduced in size
- there are strands of mucus in the tear film
- there are abnormalities of the cornea, or loss and damage to the corneal epithelium
- there is conjunctival scarring/ pathology
- position and function of eyelids is normal
You may also undergo some special tests to aid in diagnosis such as
Tear break-up test – Dr Shah will put droplets of yellow dye (fluorescein) into your eye, which help evaluate whether your eyes are drying out too quickly.
Schirmer test – placing specially designed paper strips in the eyes quantifies the amount of tears produced in the eyes
Tear samples – Dr Shah may test the your tear enzyme levels ( InflammaDry) and / or Osmolarity.
Rose Bengal test – Dr Shah may use a special dye to check for damaged cells on the surface of your eye.
Meibography- if meibomian gland dysfunction is suspected, Dr Shah may recommend special imaging of the meibomian glands and the tear film. Commonly used is the Lipiscan.
What treatments are available for dry eye syndrome?
There are three main ways to treat dry eyes:
- tear replacement
- preservation of existing tears
- reducing tear drainage.
1. Tear replacement
Tear replacement is the main treatment for dry eye syndrome. You will need to take tear replacement medicines regularly for them to work. They can reduce the symptoms of dry eye syndrome and prevent further damage to your eyes.
There are different types of artificial tears:
Eye drops – There are many different compositions for different types of dry eye. Depending on your eye condition and examination, Dr Shah will prescribe an appropriate eye drop.
Preservative free drops- are available in single doses if you become sensitive to preservatives. Eye drops need to be used often to work as well, so make sure you follow your doctor’s instructions.
Eye gels – These last longer than eye drops, so you will need to use them less frequently.
Eye ointments – These can be useful in lubricating the eye overnight. However, eye ointments are sticky and tend to blur vision.
Mucolytic eye drops – These drops can be used to break up mucus in your tears.
2. Preservation of existing tears
By controlling your environment, you can help your natural tears work better and last longer.
- Slightly lowering room temperature will help to reduce tear evaporation.
- Avoid air conditioning (you could try using a humidifier instead).
- Avoid smoking.
- Avoid or reduce your reliance on contact lenses.
- Take regular breaks when reading, using a computer or watching TV. You blink less when doing these types of visual activities, so your eyes dry out more quickly. This is the main cause for computer vision syndrome.
Immunosuppressives – If you have a condition that is inflaming your lacrimal gland, medicines to suppress your immune system can help to preserve and improve the production of tears.
Cleaning and antibiotics, – If you have blepharitis (eyelid inflammation) you should clean your eyelids regularly. You may also be given a course of antibiotics.
Omega III supplements/ flaxseed oil – reduce the symptoms of dry eye by promoting health of the meibomian glands which produces the oil (lipid) in the tears
Lateral tarsorrhaphy – If your eyelids do not close properly, the outer corners can be stitched together to improve closure
3. Reducing tear drainage
You have drainage holes (called the lacrimal puncta) on the inside corner of your upper and lower eyelids. These can be blocked temporarily with punctal plugs made of silicone or collagen or permanently with cauterisation.
This will reduce or prevent tears from draining from the surface of your eye. You can have temporary plugs inserted as an outpatient. The process is easy, quick and painless.
If your eyes water too much whilst the plug is in place, it may need to be removed.
Permanent closure of the puncta using cauterisation can be done if temporary plugging has been successful. It is a simple operation, in which Dr Shah will numb your eyelid and cauterise the puncta.
Are there any Side effects of tear replacement?
Since tear substitutes are meant to mimick the natural tears, they usually don’t have any side effects, and may be used as many times as required. However in a few people, the preservatives in the drops may cause an allergy, which can lead to
- worsening of red eyes
- worsening of sore eyes
- increased itchyness
- mild stinging and blurred vision – which usually wears off a few minutes after use.
The side effects are similar to the symptoms of dry eye. So, if you feel your symptoms are getting worse, discuss this with Dr Shah, so that your treatment may be reviewed.