How Tears are Formed
All three components of tears (lipid, aqueous and mucins) are important and necessary for the eye’s surface to be healthy and comfortable.
When the balance of the tear film components is not just right, or not enough tear film is being produced, dry eye can occur—regardless of the causes of dry eye.
Many different types of eye glands and specialized cells are involved in producing the components of tears.
- The lacrimal gland is a large gland that produces the watery portion (aqueous) of tears.
- The oily lipid component of the tear film is produced mainly by a collection of oil-secreting glands embedded along the edges of the upper and lower eyelids.
- Most of the mucins in tears are produced by goblet cells in the eyelid and on the surface of the eye.
When any or all of these glands are damaged or compromised, tear production and quality are affected. As we age, our bodies produce less oil, which is one of the causes of dry eye. Hormonal changes in women and medical therapies prescribed during menopause also affect the tear producing glands, and are also one of the causes of dry eye.
Specialized glands and cells in the eyelid help produce different parts of the tear film. A number of other cells of the eye produce important tear film components
