Dry eye syndrome and the tear film Dry eye syndrome (also known as Dry Eye Disease) occurs when environmental and other factors reduce the quantity and quality of your tears. Dry eye syndrome (also known as Dry Eye Disease) occurs when environmental and other factors reduce the quantity and quality of your tears. Healthy tears protect your eyesThe surface of your eye (called the cornea) is covered in a ‘tear film’ made up of several layers working together to keep the cornea healthy. CORNEA (eye surface) MUCIN LAYER Watery AQUEOUS LAYER Oily LIPID LAYER Healthy tear film CORNEA (eye surface) MUCIN LAYER Watery AQUEOUS LAYER Oily LIPID LAYER Healthy tear film The MUCIN LAYER Helps hold hydration to the surface of the eye. CORNEA (eye surface) MUCIN LAYER Watery AQUEOUS LAYER Oily LIPID LAYER Healthy tear film Makes up most of the tear film. It provides hydration and natural salt balance. The watery AQUEOUS LAYER