Mild dry eye conditions can usually be managed satisfactorily with artificial tear supplements, lid therapy and other common treatments. Many millions of people may suffer from dry eyes from time to time and many will be unaware of the symptoms.
Moderate dry eye may affect vision more, and will probably affect quality of life a lot more because of chronic pain, eye sensitivity, light sensitivity and restricted activities.
Severe dry eye may lead to desiccation of the corneal epithelium, ulceration and perforation of the cornea, an increased incidence of infectious disease and, potentially, serious visual impairment and blindness.
More information about dry eyes severity is available on the DEWS Report 2007.