Dry eye occurs when the eye does not produce adequate tears or when they are not of the correct consistency and evaporate too quickly.
Inflammation of the surface of the eye may occur along with dry eye and can lead to pain, ulcers, or scars on the cornea and some loss of vision if untreated. However, permanent loss of vision from dry eye is uncommon.
Dry eye can make it more difficult to perform certain activities, such as using a computer or reading for prolonged periods of time and it can decrease tolerance for dry environments, such as inside an airplane.
This is chronic inflammation of the eyelids resulting in crusting, redness and swelling. There is often a sensation of grittiness and discomfort. It is more common in young children, those with acne (pimples) and in those over 50 years of age. The exact cause of blepharitis is unknown but it is thought to be due to a reaction between the bacteria that live naturally on the skin and the oils produced by the lid glands.
Many patients with blepharitis also have associated dry eyes. There is no cure for blepharitis and treatment consists of a daily eyelid-cleaning routine and artificial tear drops.
In some cases, treatment with antibiotic and steroid eye drops may be needed. Some patients also benefit from oral antibiotics which may be required for four to six weeks or longer in more severe cases.