Dry eye syndrome is a condition that happens as a result of the low production or quick evaporation of tears, causing the eyes to become sore and inflamed. It can also be known as keratoconjunctivitis sicca (KCS), dry eye disease, or just dry eyes.
Signs & Symptoms
Dry eye syndrome normally presents symptoms in both eyes. These can include:
- Soreness or grittiness in the eyes that becomes worse as the day goes on.
- Redness in the eyes.
- Sticky eyelids, especially in the morning.
- Blurry vision.
- Eyes occasionally becoming watery as they increase tear production to soothe the discomfort.
However, the condition can present with some more severe symptoms:
- Extreme photophobia.
- Severe eye pain and redness.
- Deterioration in vision.
Severe symptoms may be a sign of a further complication related to dry eye syndrome, therefore you should speak to your GP or optometrist if you exhibit any of these symptoms.
Complications of Dry Eye Syndrome
Dry eye syndrome normally presents with mild symptoms, however in some cases the following complications could arise.
Conjunctivitis is when the conjunctiva (the outer layer of the eyeballs and the inner layer of the eyelids) becomes inflamed. It can often share symptoms with dry eye syndrome, and most cases of conjunctivitis caused by this condition present mild symptoms that don’t require specific treatment. If the conjunctivitis becomes severe you should see a specialist.
Inflammation of Cornea
If the dry eye syndrome becomes severe or doesn’t respond to treatment, it can result in the corneal surface becoming damaged. This can make it susceptible to infection or ulceration, which may lead to your vision being affected.
What Causes Dry Eye Syndrome?
Dry eye syndrome happens when there aren’t enough tears in your eyes, either because they aren’t being produced enough or they’re evaporating too quickly. There may not always be one single cause of the condition, but a variety of factors.
How the Eye Works: Tears
Your eyes are constantly covered by a film of tears which lubricate them, keep them clean, and help prevent infection. The tears are made up of water, oils, mucus, proteins, and salt, all produced by different glands and cells in the eye region.
If the tears aren’t produced in the right amount or their quality is affected it can lead to dry eye syndrome.
Tear production can be affected by the following:
Hormones are heavily involved in the production of tears, and changes in hormone levels can affect the tear production process. Hormone levels can change for various reasons, such as contraceptive medications, pregnancy, or menopause.
As you grow older you produce fewer tears and your eyelids are less able to spread them over your eyeballs, increasing the risk of dry eye syndrome.
Your eyes can become dry as a result of environmental factors such as a dry climate, high altitude, wind, hot air, or sunny weather.
Activities that require you to keep your eyes open such as reading or staring at a screen can increase the risk of dry eye syndrome as they often mean you blink less, therefore the tear coating isn’t replaced when it dries away.
Dry eye syndrome can be a side effect of certain medicines such as antihistamines, antidepressants, diuretics, or beta-blockers.
Laser Eye Surgery
Some types of laser eye surgery can result in dry eye syndrome, which can last for a number of weeks before clearing up, sometimes even longer.
Contact lenses can cause irritation in the eyes, which can lead to dry eye syndrome. Using different lenses or using glasses instead can help ease the symptoms, while changing your cleaning solution or using eye drops without preservatives can also prevent you from developing dry eyes.
Medical Conditions that can increase risk
The risk of developing dry eye syndrome can also increase as a result of other medical conditions, including:
- Blepharitis – The inflamed eyelid rims caused by blepharitis can block the Meibomian glands that produce the oily part of tears.
- Allergic Conjunctivitis – The conjunctiva can become inflamed as a result of an allergic reaction.
- Contact Dermatitis – The skin becomes irritated after coming into contact with a certain substance.
- Sjögren’s Syndrome – The eyes, mouth, and vagina become particularly dry. This condition has also been linked to arthritis and fatigue.
- Rheumatoid Arthritis – Different parts of the body become swollen and inflamed, including the eyes or skin as well as joints.
- Lupus – The immune system attacks its own body tissue, including its blood vessels.
- Scleroderma – Parts of the skin becomes tough and thick.
- Bell’s Palsy – One side of the face can become weak or paralysed.
- HIV – The immune system is attacked.
Previous trauma to eyes such as radiation exposure or burns can also increase the risk of developing dry eyes.
How is Dry Eye Syndrome Diagnosed?
Dry eye syndrome can be diagnosed by your GP after checking your symptoms and taking your medical history. They may ask about medication you are currently taking, your daily activities, and any other symptoms you have – even if they aren’t affecting your eyes, other symptoms could help the GP detect the cause of your condition.
Referral to a Specialist
You may be referred to an optometrist, who is trained to identify defections with your eyes and vision. They will normally examine your eyes to confirm what condition you have before giving advice about possible treatment.
If they are unable to diagnose you or if you require specialist treatment you may be referred to a surgeon who specialises in eye-related conditions, known as an ophthalmologist, they will conduct a variety of tests.
Fluorescein Dye Test
A fluorescein dye test involves using a temporary orange/yellow dye to make your tears more visible. The specialist will apply the drops and ask you to blink a few times then keep them open, before they shine a light in your eye to make the dye visible.
This allows them to measure the time it takes for the dye to start drying – if there are dry patches in under 10 seconds it can be an indicator of dry eye syndrome. The dye can also highlight damaged areas on the surface of the eye.
The Schirmer’s Test
The Schirmer’s test is when blotting paper strips are hooked onto the lower eyelid for five minutes before they are removed and the wetness is measured. The specialist may diagnose dry eye syndrome if the paper has less than 10mm of moisture on them.
Lissamine Green Test
The lissamine green test is when a dye is applied to the surface of your eyes using a paper strip diluted by saline. Any damage on the eye surface shows up due to the distinctive colour of the dye.
How do you treat Dry Eye Syndrome?
Dry eye syndrome cannot currently be cured, and can remain in some people for the rest of their lives. However the symptoms can be managed by a number of treatments depending on the cause.
If the symptoms are caused by a particular medication then it may help to change to a different course, and if there is another condition that is causing the dry eye syndrome your GP can prescribe treatment for it.
Lubricant treatments can be used to treat mild to moderate instances of dry eye syndrome. They can come as ointments, gels, and eye drops, and are often referred to as artificial tears – although they supply the moisture that the tears are missing, they don’t provide the nutrients that are found in real tears. Some eye drops are available over the counter, while some will require a prescription.
Oily Tear Eye Drops
Oily eye drops help restock the oil in your tear film and prevent water from evaporating. These can come in the form of liposomal sprays, which you can get over the counter without a prescription – the liposomal spray is applied to your eyelid edges while they are closed, causing it to spread over the eye surface when you open them. This creates a new tear film that helps prevent your eyes from becoming dry.
Preservatives are used in some eye-drops to stop bacteria from developing inside the bottle. It can be better to use preservative-free drops if you use them more than six times a day. The preservatives could cause damage to the sensitive cells on the eye surface, which can be particularly dangerous in severe cases of dry eye syndrome.
Eye drops containing preservatives can also be harmful for soft contact lens wearers as the preservatives can stick to the lens and damage the eye.
Eye ointments are often used while you sleep as they can cause your vision to become blurry. They help lubricate your eyes and prevent your tears from evaporating overnight if your eyes are slightly open. However they shouldn’t be used while wearing contact lenses – if you wear contacts, your GP may be able to recommend alternative treatments.
Dry eye syndrome can result in swelling and soreness around the eyes, which means your GP or optometrist might also prescribe anti-inflammatory treatments.
Corticosteroid Eye Drops and Ointments
Corticosteroids may be used if the dry eye syndrome is severe, however they can result in the development of cataracts and raised intra-ocular pressure in one of every three patients. You should be under the care of an ophthalmologist if you are given this treatment.
You may also be prescribed oral tetracyclines in small doses. The course normally lasts for at least three months but it can carry on for longer.
Ciclosporin Eye Drops
Eye departments in hospitals may prescribe Ciclosporin, a medicine that treats dry eyes but also inhibits the immune system.
Autologous Serum Eye Drops
Autologous serum eye drops are made using parts of your own blood – it involves taking blood in sterile conditions, removing the blood cells, and using the leftover serum as eye drops. However it is only available via the National Blood Service and an ophthalmologist. It may be months before it is available to use due to quality standards involved. Autologous serum eye drops are rarely used, normally when no other medications have worked.
You may require one of the following methods of surgery if the condition is very severe and no other treatment works:
A punctal occlusion is when your tear ducts are closed with small punctal plugs, helping your eyes stay moist by preventing your tears from draining away. To make sure the operation has the desired effect, they may use temporary silicone plugs before changing to permanent ones. The tear ducts may also be sealed by heat (cauterised) to permanently prevent the tears from draining.
Salivary Gland Autotransplantation
Salivary gland autotransplantation is when some saliva-producing glands are taken from your lower lip and put around your eyes, allowing the saliva to act as a replacement for tears. However this is a rare procedure that is normally only used when all other options have been tried.
How Can You Help Yourself?
There are measures you can take to ease the symptoms of dry eye syndrome and prevent it from occurring.
Your eyes can become irritated by windy or dusty conditions as well as smoke and hot air, while eye makeup such as eyeliner and mascara can obstruct the glands in your eyelids.
Specialised Eye Wear
Glasses such as moisture chamber spectacles keep moisture in while preventing irritants from entering your eyes. If your contact lenses caused the dry eye syndrome, there are different contact lens options you can discuss with your optometrist.
Computer screens can cause eye strain if they are used for a long space of time, therefore it can help to make sure your computer is set up to reduce this as much as possible. The computer monitor should be at or just below eye level, and you should take regular breaks from using the screen.
Humidifiers work by moistening the air around you, and having one at home or work can help prevent your eyes from becoming too dry. Opening the windows, either for a short time during the winter or longer when the weather is warmer, can also help retain moisture in the air. Air filters can be useful for dealing with a dusty home or workplace.
The symptoms of dry eye syndrome can be eased by keeping good eye hygiene, especially if you also suffer from blepharitis.
Warm compresses work by melting the oil in your tears, making them runnier and more able to spread over the surface. Follow these instructions to make a warm compress at home:
- Boil some water and let the temperature come down until it’s warm.
- Soak a clean towel or pad in the water and place it over your closed eyelids for ten minutes.
- The compress should be soaked in the warm water occasionally to keep it warm.
There are also microwavable eyebags that can be used instead of warm compresses, however you should clean them before and after using.
Massaging your eyelids gently can help move the oil over your eye surfaces, replenishing your oily tear film and preventing tear evaporation. You can massage your eyelids by doing the following:
- Roll your little finger slowly and circularly over your closed eyes.
- Bring a cotton bud gently down your upper eyelid towards the eyelashes, repeating over the whole of your upper and lower lids.
This may initially result in a slight irritated feeling, but this should improve over time.
Lid Margin Hygiene
You can use an eyelid-cleaning solution to clean any crusting, grime, oil, or other contaminants away from your eyes. To make a solution at home, boil some water and allow it to cool slightly in a bowl, then add a few drops of tea tree or baby shampoo, or a small spoonful of bicarbonate of soda. You can also buy eyelid-cleaning solutions commercially. Follow these instructions when you have your solution:
- Dip some clean cotton wool into the solution and use it to mop up the eyelids and surrounding area.
- Wet a cotton bud in the solution and use it to clean the eyelid edges and eyelashes.
- For each time you should use a new cotton bud or piece of wool.
Diets high in omega-3 fats have also been linked to improving dry eye syndrome. You can find omega-3 fats in oily fish such as mackerel, salmons, and herring. However canned fish may not provide the benefits as the canning process removes the oil.