How can the tear fluid be stimulated to produce?
The tear fluid fulfils several important tasks. The most important is probably that it serves to protect the cornea. It cleanses the conjunctival sac: by moistening and blinking the eyelid, small foreign bodies can be removed from the eye, substances such as lysozyme or lipocalin prevent pathogens from entering the eye and exfoliated, dead epithelial cells can be removed.
In addition, the tear film ensures that the eyelids can glide along the cornea without much friction, thus preventing irritation. Since the cornea itself is not supplied by blood vessels and therefore not by nutrients, the cornea is nourished by the tear fluid that surrounds it. Last but not least, we can of course express emotional states by crying with the help of the tear fluid.
Diseases of the lacrimal fluid
Diseases that affect the tear fluid can be divided into over- and under-functioning. An increased production of tears is usually simply the result of external stimuli such as emotional excitement, foreign bodies, chemical or physical stimuli, which reflexively trigger an increased production of tear fluid, which leads to the overflowing of tears, also known as lacrimation or epiphora. In the true sense of the word, this is therefore not a disease, but a natural process that is intended to protect the eye.
In rare cases, however, a teardrop can also be caused by a blockage in the tear ducts and must be treated. More often, however, the production of tear fluid is too low. This can be caused by taking certain medications or by external factors such as cold, dry air, smoke or wind.
In addition, the quantity is sometimes limited in unspecific conditions such as inflammation in the area of the eye. Inflammation of the tear glands themselves also occurs, but is rare. There are also certain diseases associated with dry eyes, the most important of this group is the so-called Sjögren’s syndrome.
This is an autoimmune disease in which the production capacity of several glands of the face is limited, which is why patients complain about dry eyes as well as dry mouth. In some cases, dry eyes do not cause any discomfort, but most often the eyes feel irritated, and in the worst case, corneal damage may occur, which is why dry eyes are usually treated with eye drops that can be purchased in pharmacies. Apart from that, of course, the cause of dry eyes must always be sought and an underlying disease must be treated appropriately if necessary.
