Eye tears are one of the miracles of the Creator, as they are a strange device in the way they preserve the eyes (cornea and conjunctiva) from germs, and see things with complete clarity and high resolution. This device, whose diameter does not exceed 10 microns (a micron is one in a thousand of a millimeter), includes three layers of tears, and each layer has its own composition and function. Dr. Musa Al-Harbi, a consultant cornea, keratoconus, LASIK, cataract, and intraoperative lens implantation, at the Istishariyon Center, talks about the nature of the tear system, and says:
The lacrimal system is divided into three layers
The outer layer: It is the fatty layer, and is secreted from special sebaceous glands located in the eyelid. Its function is to prevent the evaporation of the middle layer of water, to keep the eye moist all the time and to increase the sharpness of vision, by making the cornea very clear. Any defect in this layer due to inflammation of the eyelids leads to evaporative dryness.
The middle layer: It is the watery layer and is secreted from the lacrimal gland under the upper brow bone, which is responsible for lubricating the eye and is affected by the lacrimal gland affected, especially in some general diseases such as rheumatism and lupus.
The inner layer of tears: It is the mucous layer, and is secreted from many glands scattered in the conjunctiva of the eye, and its primary function is to facilitate the movement of tears on the surface of the eye, and it is affected by conjunctival diseases, such as: eye allergy, and bacterial and viral conjunctivitis diseases.
And Dr. Musa Al-Harbi points out that people have misconceptions about eye tears, most notably:
1- Some believe that dehydration is one type, which is a wrong concept, because dehydration depends on the type of tear layer affected.
2- Some believe that using moisturizing s that are widespread in pharmacies, is the best solution to treat dehydration, neglecting to go to the doctor to ascertain the cause that may be an eye disease.
3- Some believe that frequent crying and the increased secretion of tears associated with it raises eye pressure. This belief is wrong, as increased tear production has nothing to do with eye pressure.
4- Some believe that there is a difference between tears of joy and tears of sadness. In fact, there is no fundamental difference in the formation of the two, but the main responsible for the increase in secretion is the nerve impulses affected by the state of sadness or joy.
