Why are tears important for eye health?
Our tears form part of an essential coating around the surface of the eye called the tear film, which has several functions that are important for eye health:
- The tear film provides vital lubrication to the surface of the eye and protects it from external damage.
- Tears affect the way light enters the eye, which helps us to see properly.
- Protecting the eye from infection.
- Since the cornea—the clear curved surface at the front of the eye—doesn’t have any blood vessels, the tears are the main way we get oxygen and nutrients to this part of the eye.
What is dry eye disease?
Dry eye disease is a common condition that can cause severe discomfort. It occurs when the tears aren’t of a good enough quality, or are of insufficient quantity to protect the surface of the eye. Without adequate lubrication, the eye becomes dry, leading to uncomfortable symptoms such as a feeling of dryness or grittiness.
Dry eye disease increases the risk of damage to the cornea, the clear curved surface at the front of the eye. Although rare, in more severe cases or if left untreated, dry eye can become very painful and may lead to problems with vision.
What causes dry eye?
Dry eye disease is caused by the breaking up of the tear film between blinks. The tear film is composed of tear fluid, oils, and fats, which each contribute to tear film function. Dry eye disease occurs when there is insufficient tear fluid, reducing the quantity of tears, or insufficient oil, reducing the quality of tears. Oil on the surface of the tear film slows down evaporation, so insufficient oil allows increased evaporation and faster break up of the tear film. This leaves the eye without sufficient lubrication.
There are several factors that contribute to the quality of tears, which can make someone more likely to develop dry eye. One of the most common factors is age, since the hormones that regulate the rate at which we produce tears change as we get older. This is why dry eye is more common in men and women over the age of 50.
What are the symptoms of dry eye?
Symptoms of dry eye include eyes that are:
- Itchy
- Sore
- Gritty
- Painful
- Red
- Blurry
- Sensitive to light
- More watery than normal
- Visual disturbances
Who is more at risk of getting dry eye symptoms?
Dry eye disease is surprisingly common and affects men and women of all ages. It is estimated that 1 in every 3 people over the age of 65 has problems with dry eyes. It is particularly common in postmenopausal women.
Several factors make someone more likely to develop dry eye disease. Age is one of the biggest risk factors for developing dry eye because the hormones that control the rate of tear production change as we get older. Postmenopausal women are particularly at risk, for similar reasons. People who suffer from certain conditions, such as diabetes, blepharitis, Sjogren’s syndrome or lupus are also more likely to develop dry eye symptoms.
Environmental factors can also influence a person’s likelihood of developing dry eye. Persistent computer use, contact lens wear, central heating and air conditioning can all exacerbate dry eye symptoms. Side effects of some drugs may also make someone more likely to develop dry eye disease. Reducing time spent on these activities or switching medications (under the guidance of your health care professional) may help alleviate dry eye symptoms.
How is dry eye detected?
The crucial steps in detecting dry eye disease is to recognise the symptoms, identify risk factors (such as screen use) and go to a healthcare professional.
Dry eye disease is diagnosed by assessing the quantity and quality of tears. The front of the eyes and quality of tears are examined using a special microscope called a slit lamp. In addition, other tests may be used to diagnose and assess dry eye disease, such as:
Schirmer test—this test measures the volume of tears in a given time period by placing filter paper at the edge of the eyelid for five minutes analysing the amount of tears produced.
Tear breakup test—In this test, a dye is used to assess how long it takes for the tear film to break up between blinks.
What are the typical treatments available for dry eyes?
Usually, dry eye can be treated using eye drops to replace the lubrication to the eye surface. Reducing time spent on the computer, or in heated or air-conditioned environments, may also help to alleviate discomfort. A variety of eye drops are available and some patients may find they need to avoid using drops that contain preservatives, as this can exacerbate dry eye symptoms.
What happens if dry eye is not treated?
In the majority of cases, dry eye doesn’t lead to any lasting changes to vision. However, dry eye can cause unpleasant symptoms due to corneal damage, and so can have a considerable impact on a person’s quality of life. Treatment with the right eye drops can provide effective relief by improving lubrication, and also help prevent damage to the eyes surface. As well as being available over the counter, these can also be prescribed by your health care professional.
Are there any other simple methods that can be used to help dry eye symptoms?
Small lifestyle changes, such as reducing time spent on the computer and using lubricating eye drops, can help relieve symptoms of dry eye. Some do’s and don’ts are highlighted below:
Do:
- Keep your eyes and eyelids clean.
- Take breaks to rest your eyes when using a computer screen.
- Make sure your computer screen is at eye level to avoid eyestrain.
- Use a humidifier to stop the air getting dry.
- Get plenty of sleep.
- If you wear contact lenses, take them out and wear glasses to rest your eyes.
Don’t:
- Smoke or drink too much alcohol.
- Spend time in smoky, dry or dusty places.
- Spend too long in air-conditioned or heated rooms.
- Stop taking a prescribed medicine without getting medical advice first—even if you think it’s causing your symptoms.
How does dry eye affect contact lens wearers?
People who wear contact lenses have a higher risk of developing dry eye than those who do not. In fact, contact lens wearers are five times more likely to report symptoms of dry eye than glasses wearers, and an estimated 50 percent of contact lens wearers experience dry eye symptoms, at least sometimes.
Contact lenses have been linked to changes in the composition of the tear film, which affects the quality of the tears—one of the main culprits in causing dry eye. Dry eye in contact lens users can also lead to visual disturbances and increased risk of eye infection. Any contact lens related dry eye issues should be discussed with an eye specialist to determine appropriate treatment.
Recently, a drop that lubricates the eye and promotes healing of corneal damage, has been developed. It is a combination of an antioxidant called coenzyme Q10 (CoQ10) and crosslinked hyaluronic acid that has been found to be effective at relieving and treating dry eye. This combination can be found in VISUfarma’s dry eye treatment, VisuXL.
Visit https://www.visufarma.com/product/visuxl/ for more information.
References
- Herbaut A, et al. Tear film analysis and evaluation of optical quality: A review of theliterature. J Fr Ophtalmol 2019; doi: 10.1016/j.jfo.2018.12.001. [Epub ahead of print]
- Craig JP, et al., TFOS DEWS II Report, The Ocular Surface 2017; http://dx.doi.org/10.1016/ j.jtos.2017.08.003
- NHS https://www.nhs.uk/conditions/dry-eyes/ accessed February 2019.
- Shujaat S, Jawed M, Memon S, Talpur KI. Determination of Risk Factors andTreatment Of Dry Eye Disease In Type 1 Diabetes Before Corneal Complications AtSindh Institute Of Ophthalmology And Visual Sciences. Open Ophthalmol J 2017; 11:55-361.
- Postorino EI, et al. Efficacy of eye drops containing crosslinked hyaluronic acid andcoenzyme Q10 in treating patients with mild to moderate dry eye. Eur J Ophthalmol2018; 28: 25-31
- Nichols JJ and Sinnott LT. Tear film, contact lens, and patient-related factors associated with contact lens-related dry eye. Invest Ophthalmol Vis Sci 2006; 47(4): 1319-28.
