Dry eye products that increase, stabilise and restore the tear film
What is dry eye?

Dry eye occurs when insufficient tears are produced or when the tears are of poor quality and the tear film does not function efficiently. Dry eye is also known as keratoconjunctivitis sicca or dry eye disease (DED).

 

Diagram: How Dry Eye Occurs

 

Dry eye is common, studies estimate that up to 30% of people may experience it at some point in their life. It is more common in people over 60 - particularly women. Dry eye is not normally serious, there is no cure but most people can be kept comfortable using eye drops. In extreme cases dry eye can damage the eye and vision.

 

Symptoms of dry eye

  • itchy or scratchy sensations in or around the eyes
  • dryness, grittiness, stinging or soreness in the eyes that worsens through the day
  • red eyes
  • watery eyes, particularly when exposed to wind
  • ocassional blurred vision and sensitivity to normal light

 

The Tear Film

 

The tear film has three layers which protect the surface of the eye, helping to create a smooth optical surface so vision stays crisp, clear and undistorted.

cross section of eye and tear film
A healthy tear film consists of three layers with distinct and complementary functions
lipid layer


LIPID LAYER is composed of oils secreated by the meibomian glands. This is the outermost layer of the tear film covering the aqueous components and providing a hydrophobic barrier which modulates tear evaporation and retains moisture. The lipid layer also protects the eye surface from contamination.

lipid layer


AQUEOUS LAYER is produced by the lacrymal gland it is the central component of the tear film and accounts for about 98% of tear volume. It consists mainly of water but also contains other substances such as proteins, which nourish the eye and electrolytes. This layer also washes away irritants, keeping the eye healthy. It helps maintain optimum vision by promoting spreading of the tear film across the cornea.

lipid layer


MUCIN LAYER is the inner and foundation layer of the tear film which anchors the film to the cornea. It is produced from goblet cells within the conjunctiva. Its key functions are to facilitate film distribution evenly over the corneal surface and adherence to the corneal epithelium.