Dry eye is an illness which, despite its usually harmless nature, can be extremely annoying for the patient and usually leads to lengthy treatment.
If left untreated, severe dry eye can lead to corneal clouding and thus to significant visual impairments. The good news, however, is that this can be avoided with consistent treatment.
The tear film of the eye moistens the conjunctiva and cornea, preventing the surface of the eye from drying out. Lacrimal fluid also facilitates eye and eyelid movements, protects the eye from mechanical (light, heat, cold) and physical aggressors, such as foreign bodies, and also has a cleansing and antibacterial effect.
Reduced lacrimal production or increased evaporation of the tear film can cause your eyes to dry out – this condition is known as dry eye (sicca syndrome in technical medical terminology). A distinction is made between the hyposecretory type (i.e. the lack of tear production) and the evaporative type (i.e. the increased evaporation). Both forms are classified as an inflammatory reaction of the surface of the eye. Patients usually suffer from a combination of these two types of dry eye.
Having dry eyes is not only unpleasant, but also usually affects your everyday life. Since dry eye can damage the cornea if left untreated, it is always advisable to consult an ophthalmologist if you feel that your eyes are not producing enough moisture.
The good news is that, if dry eyes are suspected, the ophthalmologist can quickly make the correct diagnosis using a wide range of tests. In most cases, moisturising eye drops and regular eyelid rim cleansing will effectively alleviate your symptoms.
Dry eyes can lead to a variety of symptoms, such as itchy, burning, tired and red eyes, or a feeling of having a foreign body in the eye. Dry eyes can even cause your eyes to water. Depending on the severity of the dry eye, even the cornea and conjunctiva may be affected. Depending on the manifestation, vision may also deteriorate slightly to considerably (blurred or distorted vision).
Overview of the symptoms of dry eye:
There are several reasons for why you might develop dry eyes: For example, a disruption of the tear film, and certain medications, illnesses or environmental influences can trigger the symptoms. Another main cause of dry eyes is the rapid increase in digital screen time.
Smoking or certain climatic factors such as heating or air conditioning can also contribute to the development of dry eye. Hormonal influences such as pregnancy, menopause and/or taking hormone preparations such as the contraceptive pill also play a role. Drugs (e.g. antihypertensive drugs or medication to slow the heart rate), sleeping pills and sedatives, diuretic and anti-allergy medication (antihistamines) may also contribute to developing dry eye.
Contact lenses or drops to reduce reddened eyes may cause the eyes to dry out. Inflammation of the rim of the eyelid can also have a negative effect on tear quality: clogged gland exits reduce the fat component of the tear film, which makes it easier to evaporate. Lifting the eyelid can also lead to dry eye.
Other risk factors include older age, diabetes or skin diseases such as atopic dermatitis.
The ophthalmologist will first examine the skin on your face and eyelid as skin changes are often associated with dry eye.
They will also observe your blink rate, eyelid closure, eyelid rim with the eyelid glands (meibomian glands) and your eyelid position.
The time between blinking of the eyelid and the “ripping” of the tear film provides information about the stability and quality of the tear film. The ophthalmologist stains the cornea with a dye (= fluorescein) and then observes possible changes using a microscope.
A strip of filter paper attached to the conjunctival sac can be used to measure the amount of watery tear production. This method is known as Schirmer’s test.
This investigation can be further underpinned by other special investigations, for example with interferometry, which allows the important oil content of the tear film to be assessed even more precisely. In addition, the meibomian glands (glands along the edge of your eyelids) can be made visible by means of a meibography (i.e. imaging of the meibomian glands in the eyelids using infrared technology).
Finally, an analysis of the composition of the lacrimal fluid can be carried out to determine its salt content or to prove the presence of inflammatory proteins.
Fortunately, the symptoms of dry eye can be dealt with quickly with the right treatment:
Eye drops: If your eyes feel dry and tired, eye drops are the first remedy of choice. They can alleviate the symptoms quickly and reliably by moisturising the surface of the eye and relubricating the blink mechanism. Drops also form a protective film that can prevent irritation.
Moisturising the surface of the eye at night: Sometimes eye drops alone are not enough to treat dry eye. If the eyes are permanently irritated, they need special support, especially at night. As regular moisturisation with eye drops is not possible when you are asleep, the eyes need a fatty protective film that can be produced by applying a rich eye ointment that forms a protective layer over the surface of the eye for several hours.
Heat treatment for daily eyelid rim hygiene: Cooling eye masks reduce eyelid puffiness after a bad night’s sleep. But there are also warming eye masks that are intended for intensive eye care. Heat treatment loosens crusty build-up along the edge of the lid and blockages in the sebaceous glands. The blood flow to the eyelids is improved and the symptoms alleviated. Incidentally, it can also be used to treat styes and meibomian cysts.
Since dry eye is by no means a harmless condition, but can be an expression of serious diseases of the surface of the eye or of other general illnesses, it is recommended that an ophthalmologist check whether the prescribed medication is actually taking effect.
The following preventive measures are recommended:
Dry eyes are diagnosed by means of a slit-lamp examination, Schirmer’s test or the tear-film rip time. Dry eye cannot be cured once it develops – however, various therapies, such as special eye drops, can significantly alleviate the symptoms.
Yes, it can. Chronic dry eye can cause sensitivity to light or visual impairment and poor vision; even if the eye often feels tired and irritated, this can be a sign of the dry eye.
