What causes dry eye?
Tears are essential for maintaining the health of your eye’s front surface – the cornea – and for providing clear vision.
Every time you blink, tears spread across the cornea, providing lubrication, reducing the risk of eye infection, washing away foreign matter and keeping the eye’s surface smooth and clear. Excess tears pass out of the eye through drainage ducts into the nose.
Dry eyes can occur when tear production and drainage is not in balance – when your eyes either do not produce enough tears or your tears are of poor quality.
Inadequate amount of tears;
Tear production tends to diminish with age, with various medical conditions, as a side-effect of some medications or with the impact of wind and dry climates.
Poor quality of tears;
Tears comprise three layers – oil, water and mucus – which protect and nourish the front surface of the eye. If the tears evaporate too quickly or don’t spread evenly due to deficiencies with any of the three tear layers, dry eye symptoms can develop.
What are the symptoms of dry eye?
- Excess watering
- Itchy, scratchy or burning eyes
- A feeling of something “in” your eyes (foreign body sensation)
- Blurred vision
- Light sensitivity
- Difficulty reading, using a computer, watching TV and driving
How is dry eye diagnosed?
Dry eye is diagnosed through a comprehensive eye examination. This might include:
- Vision tests
- Examination of the eyelids and eyes with the slit lamp
- Measurement of how quickly the tear film evaporates
- Corneal fluorescein staining to show the dry areas on the cornea and ocular surface
How is dry eye treated?
Dry eye can’t be cured and ongoing treatment is required.
Treatment is aimed at relieving symptoms, keeping your eyes heathy and comfortable, and preventing vision impairment. It can include:
- Adding tears by using artificial tear drops
- Using warm compresses and massage around the eyelids
- Using eyelid cleaners to help decrease inflammation and bacteria around the eyelids
- Taking an omega-3 fatty acid nutritional supplement
- Using topical steroids
- Conserving tears by blocking the tear ducts from which tears drain
- Intense pulsed light (IPL). Usually associated with hair removal, IPL has also been used to reduce inflammation along the rim of the eyelids.
- Thermal pulsation which applies heat and light pressure to the oil-producing gland along the rims of the eyelid to promote oil flow.
You can take the following steps to reduce symptoms of dry eyes:
- Remember to blink regularly when reading or using computer or tablet screens
- Increase the humidity in the air at work and home
- Wear sunglasses outdoors, particularly sunglasses with wrap-around frames
What is blepharitis?
Blepharitis is a common, inflammatory condition that affects the lid margins and eyelids and causes itching and irritation. It can result in a red, sore eye with grittiness and burning. Your eyelids can appear red and swollen and can accumulate a crusty or scaly build-up at the roots of your eyelashes.
While it is a chronic (long-term) condition, blepharitis is generally not sight-threatening and is not contagious, but it can lead to other conditions like dry eye syndrome.
What causes blepharitis?
Blepharitis can develop at any age, but is more common in people over 40. While there is no direct cause of blepharitis, it can be associated with:
- Skin conditions such as rosacea and seborrheic dermatitis
- Bacterial infection of the eyelids
- Allergic conditions like asthma
- The use of cosmetics and eye make-up
What are the symptoms of blepharitis?
- Red and sore eyelids, particularly the lid margins
- Eyelids that stick together and are difficult to open, particularly when you wake up
- Eyelashes that become crusty, scaly or greasy
- A feeling of grittiness and burning in the eyes
- Excessive tear production (watery eyes)
- Foreign body sensation (a feeling of having something in your eye)
- Cysts or styes in the eyelids
- Blurring of vision
How is blepharitis diagnosed?
Blepharitis is diagnosed through a comprehensive eye examination.
How is blepharitis treated?
Your treatment will depend on your specific type of blepharitis and the severity of your condition.
The key to treating most types of blepharitis is keeping your eyelids clean and free of crusts. This requires an ongoing cleaning routine for as long as you have been told by your ophthalmologist – in many cases this may be forever.
More severe cases may require a combination of anti-inflammatory medications and antibiotics that are either applied to the eye or eyelid directly, or taken as tablets.
Your ophthalmologist will fully explain blepharitis treatments to you. Most treatments are simple and can be done at home.
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