What is dry eye?

Dry eye results from the break up or lack of a tear film that normally lubricates your eyes, to provide moisture, protection and clear, comfortable vision.

Dry Eye Syndrome (DES also known as keratoconjunctivitis sicca (KCS) or keratitis sicca) can be caused by a number of different factors, including environmental issues, certain types of medications and preexisting medical conditions.

For example if you spent longer time in an air-conditioned room, or after intense computer work the natural tear film breaks up more quickly. This is also called “Computer Vision Syndrome” (CVS).

For your eyes to stay healthy, the surface needs to be continuously lubricated by a tear film.

The tear film – so much more than ‘salty’ water

Tears are a complex liquid system that helps your eyes to stay moist, healthy and comfortable. They essentially consist of three main components (image 1):

An external, thin layer of oily substances (lipids), which prevents rapid evaporation of the relatively large, water-based (aqueous) tear layer located underneath it that supplies the cells of the eye (ocular) surface with oxygen and nutrients. For the tears to spread easily and evenly on the eye, the third and innermost layer of the tear film – the so-called mucine layer – consists of proteins (mucins) and sticks (adheres) perfectly to the cells of the eye surface (cornea) and conjunctiva (lines the inside of the eyelids and covers the white part (sclera) of the eye.

Every time you blink, the tear film protects and lubricates your eyes and washes away foreign bodies that might cause harm or obscure your vision.

What is Dry Eye

  1. Superficial layer of lipids
  2. Aqueous layer

  3. Mucine layer

  4. Surface of the cornea
    1. When the tear film breaks up

      When the composition of the tear film is disturbed or the tear glands no longer produce enough of this essential liquid, the tear film may break up too quickly (=tearing of the tear film) and dry spots may develop on the eye surface (image 2). The result: itching or burning of the eyes, or even a ’gritty’ sensation that feels as if you had sand or glass in your eyes, which is often associated with a lot of pain. In advanced stages, this can cause injury to the eye surface.

      What can cause dry eye?

      Common causes of dry eye are aging, hormonal changes in women entering menopause, pregnancy, taking oral contraceptives or hormone replacement therapy, as well as diseases such as asthma, diabetes, autoimmune diseases, including Sjögren’s Syndrome or simply smoke, wind or contact lenses.

      For a majority of dry eye sufferers a defect of the lipid layer of the tear film is the trigger of the dry eye complaints. The lipid layer is a very thin layer of fat, composed of lipids produced by the Meibomian glands. This lipid layer protects the tears from evaporation and prevents tears from running over the lid margin. A lack of these lipids results in an increased evaporation of tears.

      Burning, itching, tearing, foreign body sensation or the sensation of dry eyes are symptoms of irritated eyes. These can also be caused by insufficient moisture or by hypersensitivities (i.e.: allergies) to substances like pollen, animal hair or household dust, for example. As both can present with similar symptoms, it can be difficult to differentiate between a dry eye or an allergic eye.

      Dry eye is one of the most common complications following eye surgery.

      Continuous and sufficient lubrication is necessary to regenerate injured superficial tissues of the eye.

      What are symptoms of dry eye?

      Dryness is the most obvious symptom, but there are a variety of ways how dry eye sufferers perceive their problems:

      • Scratchy, burning or stinging eyes
      • Foreign body sensation (feels like something is in your eyes)
      • Tired eyes
      • Blurry vision
      • Sensitivity to light
      • General eye discomfort
      • Excessive tearing*

      If you experience one or more of the symptoms above, you may have dry eye syndrome. Because dry eye can be confused with other eye conditions, it’s best to see your eye doctor and get a proper diagnosis.

      How is aqueous dry eye treated?

      One of the most common strategies doctors use to manage dry eye symptoms is to lubricate the eye. Applying lubricants (also called artificial tears) provides immediate relief.

      HYLO™ provides immediate relief from dry eye symptoms and provides long-lasting moisture to the surface of the eye to efficaciously support the natural process of healing.

      » Discover Hylo™

      How is evaporative dry eye treated?

      A defect of the lipid layer of the tear film is often the trigger of the dry eye complaints. The lipid layer is a very thin layer of fat, composed of lipids produced by the Meibomian glands. This lipid layer protects the tears from evaporation and prevents tears from running over the lid margin. A lack of these lipids results in an increased evaporation of tears.

      CALMO™ Eye Spray stabilizes the lipid layer of the tear film, regulates and improves the humidification of the eye surface and the eyelids.

      » Discover CALMO™ Eye Spray

      Dry eye or allergic eye?

      Burning, itching, tearing, foreign body sensation can be caused by insufficient moisture or by hypersensitivities (i.e.: allergies).
It can be difficult to differentiate between a dry and an allergic eye. In these cases HYLO™DUAL is advantageous thanks to the dual mode of action of Sodium Hyaluronate and Ectoine.

      » Discover HYLO™-DUAL

      What happens while we are asleep?

      Tear production stops during sleep. Dry eye sufferers often wake up with sticky, crusty eyelids causing severe discomfort. The friction can also cause the conjunctiva and the edges of the eyelids to become irritated and inflamed.

      OCUNOX™ improves the tear film and protects the surface of the eye at night.

      » Discover Ocunox™

      *Oddly enough too many tears are a common dry eye symptom. If the surface of your eye has been damaged and cannot hold onto the tear film as it normally does, your tear-producing glands may produce even more tears to flush the eye.

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