Dry eye is a disease of the tears and the surface of the eye that causes symptoms of discomfort, visual disturbance, and tear film instability with potential damage to the ocular surface.
In recent years, the cases of dry eye have sharply increased, in the face of the deterioration of our living conditions(pollution, air conditioning, etc.). Today, nearly a third of the adult population is affected.
There are 2 types of dry eye syndrome
1 – Dry eye due to lipid insufficiency (80% of cases)
In this case, the lacrimal gland is functioning properly, but the tears evaporate too quickly due to an altered lipid layer.
The alteration of the lipid layer is usually caused by :
- meibomian gland dysfunction (glands blocked by meibum that is too thick)
- wearing contact lenses
- an eyelid condition, an allergy …
- a low frequency of blinking (working in front of screen, television, etc.)
- environmental conditions such as wind or low humidity
- air conditioning (extended trips by plane or car)
2 – dry eyes due to lacrimal insufficiency
The lacrimal gland does not produce enough of the water component of tears to keep the surface of the eye healthy. This may be related to aging or caused by a disease (Gougerot Sjögren Syndrome), medication, or a blocked tear duct.
What are the symptoms of dry eye ?
- Tingling, itching
- Burning, gritty, or foreign body sensations in the eyes
- Sensitivity to light, tobacco smoke or wind
- Discomfort when opening the eyes in the morning, feeling of glued eyelids
- Tearing up in the wind, cold, while reading …
- Difficulty wearing contact lenses
To better understand
The tear film that covers the ocular surface is made up of 2 layers:
- the mucino-aqueous layer produced by the lacrimal glands
- the lipid layer produced by the meibomian glands, which prevents the evaporation of tears
Lipid layer intact
Lipid layer altered