"Doctor, doctor my eyes are stinging." I come across this very common complaint in my daily practice as a ocular surface specialist. Patients may also suffer from red eyes, a gritty feeling, a burning sensation due to prolonged screen use, or even excessive tears when the wind blows or the air is cold. They come to our practice saying: "I've been told I have dry eyes, but the tears are flowing from them... I don't understand why it's happening and the artificial tears I've been prescribed aren't helping me."
Eye dryness or "dry eye" encompasses situations where there is dysfunctional tear syndrome or a poorly lubricated ocular surface. This may be due to a low amount of tears (aqueous deficiency) and/or poor quality tears (evaporative).
The most frequent causes of dry eye: blepharitis, old age, hormones, menopause, toxic habits, dietary habits, contact lens overuse, refractive surgery like LASIK or PRK, medication (like anxiolytics, anti-depressants, anti-histamine tablets, anti-hypertensive drugs, etc.), systemic illnesses (diabetes, hyperthyroidism, atopy, high cholesterol, hepatitis, etc.), multiple operations on the ocular surface, eyelid surgery, prolonged use of topical medication like hypotensive drugs or painkillers, lacrimal gland tumours, radiotherapy on the eyes or surrounding areas, Sjögren's syndrome, eye allergies, chronic exposure to the sun, burns, etc.
An exhaustive anamnesis is fundamental as most cases of dry eye are mild and easy to treat. In cases that come to us for a second opinion, the eye specialist may request tests to assess the quantity and quality of the tears, corneal sensitivity, the state of the Meibomian glands, conduct a biopsy or culture, a blinking pattern study, a tear clearance study, and different vital stain studies for a more in-depth study of the eye surface. In cases where association with a systemic disease is suspected, a blood test may be essential in order to rule out an autoimmune origin, and even a salivary gland study as dry eye and dry mouth may be associated with each other.
The use of artificial tears, eyelid hygiene and a diet rich in Omega 3 oils are fundamental in gaining a full clinical picture. Next generation lubricants (drops, gel or ointment) do not contain preservatives and have regenerating properties. Some also come with integrated sun block, vitamins or lipid components for cases of evaporative dry eye. These components are used to obtain a more stable lacrimal film. There are now new products for eyelid hygiene that contain antiseptics and anti-inflammatory drugs. For blepharitis, there is eyelid microexfoliation and Meibomian gland probing. In one-off cases, the use of anti-inflammatory drugs, immunomodulating agents, and even the use of cell therapy with the patient's own blood (autologous serum or plasma-rich in growth factors) may cure many of the possible lesions in patients with severe dry eye.
We must highlight that by treating the cause of eye dryness, patients may get better and end up living a very normal life without having to depend on eyedrops, although there are chronic cases that require life-long treatment.