People with dry eyes either do not produce enough tears or have a poor quality of tears. Dry eyes is a common and often chronic problem particularly in old adults.
With each blink of the eyelids tears are spread across the front surface of the eye known as cornea. Tears provide lubrication, reduce the risk of infection, wash away foreign matter in the eye, keep the surface of the eye smooth and clear. Excess tears in the eyes flow into small drainage ducts in the inner corner of the eyelids which drain into the back of the nose.
Dry eyes is a condition where there are insufficient tears in the eye to lubricate and nourish the eye. Tears are the complex mixture of water, fatty oil and mucus. Each component serves a function in protecting and nourishing the front surface of the eye. A smooth oil layer helps to prevent water layersevaporation. Mucus/ mucin layers spread the tears evenly over the eye surface. Dry eye is often a chronic problem.
People with dry eyes have stinging, burning and scratchy sensation in the eye. People with dry eye also experience sensitivity to light, foreign body sensation, excessive tearing, difficulty in wearing contact lens, blurred vision, etc.
The etiology of dry eyes
Inadequate amount of tears: Tears are produced by several glands in and around the eyelids. Tear production tends to diminish with age, with various medical conditions or as a side effect of certain medicines. Environmental conditions such as wind, dry climate can also affect tear volume by increasing tear evaporation.
Poor quality of tears: tears are made of three layers i.e. water, oil and mucus. If the tears evaporate too quickly or do not spread evenly over the cornea due to deficiencies with any of the three tear layers, dry eyes symptoms can develop.
Causes of dry eyes
Age: The majority of people over age 65 experience some symptoms of dry eyes.
Gender: Women are more likely to develop dry eyes due to hormonal changes caused by pregnancy, use of oral contraceptives and menopause.
Medication: Certain medicines including decongestants, blood pressure medication, anti depressant, can reduce the amount of tear production in the eyes.
Environmental conditions: Exposure to smoke, wind and dry climates can increase dry eyes. Failure to blink regularly such as while staring a computer screen for long period of time can precipitate dry eyes.
There are number of steps that can be taken to treat dry eyes. Generally treatment for dry eyes is to restore or maintain amount of nourished tears in the eyes to reduce dryness and maintain healthy eyes.
Tear drops: The use of artificial tear drops is the primary treatment. These drops can be used as needed to supplement natural tear production.
Conservation of tears: This is a procedure in which the tear ducts are closed permanently. This reduces the symptoms by keeping the natural tears in the eye for a longer time.
- Regularly blink the eyes while reading and working on computer
- Wearing proper sun glasses to reduce exposure to dry wind and sun
- Drinking plenty of water
- Increasing level of humidity in the air at work and at home
- Avoid use of air conditioners