Dry eye refers to the reduction of quality of the tears produced for the eyes. Tears are important to keep the front of the eyes, especially the cornea (the front window of the eye) well lubricated. Tears are produced by the glands around the eyes and have three separate layers: mucous, aqueous and lipid layer. The quality of these layers determines how well lubricated the eye is. If the quality of tears is poor, then the tears will just slide off the eyes, like water off a duck’s back and not do their job properly. This can lead to the brain sending more tears to try and fix the problem, unfortunately, the same poor quality of tears are secreted and this can lead to watery eyes.
Poor production of tears can be caused by age, medication, general health conditions, contact lenses or even dehydration. There can also be increased tear evaporation caused by environmental factors like air-conditioning or poor blinking. Eyelid problems can also cause poor spreading of the tears, or the eyelids may not fully close over at night leaving the cornea to dry out.
The treatment for dry eyes depends on the cause, the first line of treatment can include in home therapy and behavioural changes like blinking more often, followed by lubricant drops, gels and nutritional supplements and finally prescription medication and medical procedures to help cure dry eyes.