Dry Eye Syndrome, also known as keratoconjunctivitis sicca, is a chronic condition characterised by inflammation of the ocular surface and a reduction in quality and/or quantity of tears. Dry Eye Syndrome is usually categorised into either aqueous or evaporative tear deficiency, but these can overlap and co-exist.
Aqueous tear deficiency is when there is a reduction in aqueous secretion from the lacrimal glands; exocrine glands located above the eyeball. Evaporative tear deficiency is where there is an increase in the evaporation of the tear film, often due to a deficient lipid layer in the tear film.
Dry Eye Syndrome can affect people of any age, although it is more prevalent in women and in older people. It is believed that 15-33% of people aged 65 or over have dry eye disease. The symptoms of Dry Eye Syndrome include:
There are a variety of factors that can cause the disruption of the tear film leading to dry eye. There are three layers to the tear film: fatty oils, aqueous fluid and mucus. Issues with any of these layers can lead to dry eye. Causes of tear film dysfunction can include hormone changes, autoimmune diseases, allergies, extended use of computer screens, dry environments (e.g. air conditioning), and multiple other factors.
Nationally recognized guidelines from both Moorfields Eye Hospital and NICE all include the use of ocular lubricants as part of the treatment pathway for patients suffering with dry eye syndrome.
Moorfields Eye Hospital
Moorfields Eye Hospital is the leading provider of eye health services in the UK, and a world-class centre of excellence for ophthalmic research and education. Moorfields states in its guidelines to treating dry eye:
‘mild to moderate cases of dry eye syndrome can usually be successfully treated using over-the-counter artificial tear drops; if a patient has severe symptoms and needs to use eye drops more than six times a day, or if they wear contact lenses, advise them to use preservative-free eye drops’
The National Institute for Health and Care Excellence provides national guidance and advice to improve health and social care within the UK. NICE recommendations for dry eye management include:
‘recommend use of tear supplements (sometimes called artificial tears or lubricant eye drops… Consider preservative free formulations if; the person is intolerant of preservative in tear supplements; has moderate to severe dry eye disease requiring drops more than 4 times per day; is using multiple preserved topical medications; or uses soft or hybrid contact lens.