John D. Sheppard, MD, Chief Medical Editor
The understanding of keratoconjunctivitis sicca (KCS), also known as Chronic Dry Eye Disease or Dry Eye Syndrome, has changed dramatically in recent years. Until the late 1990s, KCS was thought to have been due to aqueous insufficiency. Today, KCS is understood to be a multifactorial disease that also involves inflammation of the ocular surface and lacrimal gland, neurotrophic deficiency, and meibomian dysfunction. Delay in treatment may cause disease of the ocular surface. The American Academy of Ophthalmology, in November 2003, released guidelines for treatment that recognizes these contributing factors to the epidemiology of KCS and provides evidence-based guidelines for treatment. This collection of review articles places the etiology of KCS, the AAO recommendations, and the most recent advances in treatment in perspective for practitioners, MCOs, and physicians and pharmacists who serve on pharmacy and therapeutic committees.