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- What is Dry Eye Syndrome?
- Diagnosing Dry Eye Syndrome
- What Causes Dry Eye Syndrome?
- Help for Dry Eye Syndrome
- More Information on Dry Eye Syndrome
What is Dry Eye Syndrome?
Tears naturally cleanse the eye, washing out dust and minute debris while at the same time keeping the eye moist. Tears also contain enzymes that neutralize any harmful microorganisms that may colonize in the eye causing a variety of eye problems.
Tears are formed in several glands around the eye. The water layer is produced in the lacrimal gland which is located under the upper eyelid, while several smaller glands in the lids produce the oil and mucus layers. Each time you blink, the eyelids spread the tears over the eye.
When the numerous tear glands in the eye produce fewer tears than they should, there is a chronic lack of lubrication and moisture in the eye, a condition known as Dry Eye Syndrome.
The Three Layers of Eye Defense
In healthy eyes, a thin film of liquid usually coats the eyes. This liquid film consists of three layers. The innermost layer is the thinnest and is called mucin (mucus). This thin layer coats the cornea (the eye’s clear outer window) and forms a foundation so that the tear film can adhere to the eye. The mucus helps the watery layer to spread evenly over the eye.
The middle, watery or aqueous layer is the largest and thickest. It provides moisture and supplies oxygen as well as other vital nutrients to the cornea. It also helps to flush out dust, dirt or foreign objects that may enter the eye. This layer is a very dilute saltwater solution made up of 98 percent water along with small amounts of salt, proteins and other compounds. Defects of the aqueous layer are the most common cause of dry eye syndrome.
The outer layer is a very thin layer of lipids (fats and oils). These lipids are produced by the meibomian glands and the glands of Zeis (oil glands in the eyelids). The primary function of the outer layer is to help prevent evaporation of the watery layer beneath it.
Diagnosing Dry Eye Syndrome
The symptoms of dry eye syndrome include persistent dryness, redness, scratching, irritation or burning. Often people with this condition may experience a feeling that something is in the eye.
Ironically, sometimes symptoms of dry eye syndrome may even cause watery eyes as the excessive dryness works to over stimulate production of the watery component of your eye's tears.
Symptoms of Dry Eye Syndrome
- Aging (because fewer tears are produced as we age)
- Menopause (due to hormone fluctuations)
- Side effect to medication (such as antidepressants, antihistamines, birth control pills, or certain blood pressure or Parkinson’s medication)
- Thyroid conditions
- Vitamin A deficiency
- Parkinson’s Disease
- Sjogren’s disease
- Dry, dusty or windy climate
- Insufficient blinking (especially when staring at a computer screen the entire day)
- Thermal or chemical burns
- Long-term wearing of contact lenses
Tests for Dry Eye Syndrome
If you believe you are experiencing symptoms of dry eye syndrome you should visit your physician. The diagnosis of dry eye syndrome will be based on an examination of the eye. An ophthalmologist will look at the film of tears on the eye by using a biomicroscope (a slit lamp). A dye called fluorescein may be inserted into the eye to make the tear film more visible. A Schirmer’s test (a thin strip of filter paper) may be performed to measure the production rate, evaporation rate and quality of the tear film. Special drops may also be used to diagnose the presence and extent of the dryness.
What Causes Dry Eye Syndrome?
Dry eyes can also be a symptom of some systemic diseases such as lupus, rheumatoid arthritis, Rosacea or Sjogren's Syndrome. In addition, you may experience blurred vision that may improve with blinking or excessive tearing as often occurs after watching television, reading or working in front of a computer.
Help for Dry Eye Syndrome
Dry eye treatment will vary according to the person’s needs. Regular use of artificial tears (lubricating eye drops) may alleviate the symptoms of dry eyes, however certain product ranges of artificial tears are watery and may only provide temporary relief, others are thicker and help your eyes to increase tear production.
Be sure to obtain preservative-free artificial tear eye drops as part of your dry eye treatment- they are soothing and contain fewer additives that could potentially irritate they eye further.
More Information on Dry Eye Syndrome
Tips for Taking Care of Your Eyes
- Always wear sunglasses when outdoors to avoid exposure to the wind, sun and dust.
- Take regular ‘eye breaks’ when working on the computer.
- Exercise your eyes frequently by shifting your focus from near objects to objects in the far distance and back again.
- When indoors, it’s a good idea to use an air cleaner that can filter dust and other particles from the air, but avoid using a humidifier.