Kerato-conjunctivitis sicca, or dry eye syndrome, is among the most frequently established diagnoses in ophthalmology. Dry eye syndrome is a group of extremely diffuse pathological conditions. It can be observed at any age and is characterized by different patterns of severity but tend to increase with age. Although international epidemiological studies investigating the prevalence of dry eye disease are rare, published studies indicate that between 5%[1] to 35%[2] are affected at various ages.

As dry eye syndrome can result from and appear in a variety of different ways, one speaks of it when either not enough tears are produced or they are not produced properly but also when they are not of the correct consistency and evaporate too fast. Depending on the concerned part of the tear film (watery or lipid) you can differentiate between dysfunctional tear syndrome, lacrimal keratoconjunctivitis, evaporative tear deficiency/evaporative dry eye disease (EDED), aqueous tear deficiency/Meibomian gland dysfunction (MGD), and LASIK-induced neurotrophic epitheliopathy (LNE).

Typical symptoms include stingy or burning, pain and redness, foreign body sensation, blurred vision, decreased tolerance to computer screens or dry environment, eye fatigue and many more. These irritations are experienced by the patient as very uncomfortable sensations.

Consequently the repair of the natural tear film should be the main focus.