Vol.14 Tear Function and Dry Eye

We cry when we experience strong emotions, such as happiness, sadness, frustration, and other feelings. However, tears are not the only factor that overflows when we are emotional. The eye surfaces are constantly moistened by tears. In this issue, we introduce the functions of tears in “dry eye,” a condition in which tears become dry.

 

Two Types of Tears: Their Functions
Our tears are divided into two types. The first type is the “basic secretory tears,” where tears are constantly supplied and stored on the eye’s surface. These tears keep the eye from drying out, deliver oxygen and nutrients, supply essential vitamins and proteins, and remove debris and old, worn-out cells.

The second is called “tears of stimulation and reflex secretion.” These tears are produced in response to emotions, such as feeling moved or sad. They also appear when the eyes are irritated by substances like onion vapors or when they need to flush out foreign objects to protect the health of the eyes.

When looking at a mirror on the upper or lower eyelids, small openings may be noticed. These tear ducts allow old tears to drain away. Tears are sucked out through these ducts, and they flow into the nasal cavity.
Dry Eyes
Tears are always present on the eye’s surface, and we have discussed their importance. However, if the eye’s surface does not have enough tears and becomes dry, symptoms such as eye pain, redness, fatigue, and discomfort may appear. These condition is known as “dry eye.”

An estimated 20 million patients in Japan have dry eyes, including those with preexisting dry eye conditions.

The causes of dry eyes vary but are thought to include increased use of computers, prolonged use of contact lenses, dry air, and reduced blinking.

To treat dry eyes, convenient eye drops are recommended. The basic eye drop is an artificial lacrimal fluid with properties similar to tears. They supplement tear deficiency and are safe for long-term use. In addition, if vision is impaired and the power of glasses or contact lenses is incorrect, blinking may decrease because of eye straining, which can lead to dry eyes. Therefore, it is important to re-examine your vision. In addition, when using a computer, try to soften the strain on the eyes and create an environment that is easy for the eyes by adjusting the air conditioning and humidity.

Let’s explore the important functions of tears to lead a life that is gentle to the eyes.

 

 

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