Keratoconjunctivitis sicca (KCS), also called keratitis sicca, sicca syndrome, xerophthalmia, dry eye syndrome (DES), or simply dry eyes, is an eye disease caused by decreased tear production or increased tear film evaporation commonly found in humans and small animals. Keratoconjunctivitis sicca is Latin and the literal translation is "dryness of the cornea and conjunctiva".
The typical symptoms of keratoconjunctivitis sicca are burning and a sandy-gritty eye irritation that gets worse as the day goes on. Symptoms may also be described as itchy, stingy or tired eyes. The symptoms are often caused by a loss of water from the tears that results in tears that are too "salty" or hypertonic.
Keratoconjunctivitis sicca usually occurs in people who are otherwise healthy. It is more common in old age, because tear production decreases with age. In rare cases, it can be associated with rheumatoid arthritis, lupus erythematosus, Sjögren's syndrome and other similar diseases. It may also be caused by thermal or chemical burns, or (in epidemic cases) by adenoviruses. A number of studies have found that those with diabetes are more at risk for the disease.
The best treatment strategies are designed to rehydrate the tears and eye surface. These include hypotonic, electrolyte-balanced lubricant eye drops, although these provide temporarily relief only. Other such treatment strategies also include omega-3 supplementation, punctal plugs (tiny, usually silicone plugs inserted into the tear ducts to prevent tear drainage, trapping tears in the eyes), and moist chamber spectacles. Avoiding environmental aggravation such as air conditioning, smoke and dust may help. Inflammation occurring in response to tears film hypertonicity can be suppressed by mild topical steroids or with immunosuppressants such as ciclosporin. Prescription eye drops Restasis claims to increase tear production over a period of time.
Consumption of dietary omega-3 fatty acids is associated with a decreased incidence of dry eyes syndrome in women. This finding is consistent with postulated biological mechanisms.