KERATOCONJUNCTIVITIS SICCA: Keratoconjunctivitis sicca (KCS) or aqueous tear deficiency is an acquired disorder, predominantly affecting women age 40 & older. Patients complain of blurring, dryness, foreign body sensation, blurred vision, and photophobia that often worsens as the day progresses and is exacerbated by dry, windy weather. Slit lamp examination reveals a diminished tear meniscus, strands of mucous in the precorneal tear film and the inferior conjunctival fornix, a decreased Schirmer test, and corneal surface drying with diffuse punctate erosions and conjunctivitis over the interpalpebral area. Ocassionally, filaments representing desiccated and sloughing epithelial cells mixed with mucin may form on the cornea.

The cornea and conjunctiva often stain brightly with rose bengal in an exposure pattern; staining with fluorescein is usually less impressive. KCS can occur independently, but it can also be associated with an underlying connective tissue disease, such as rheumatoid arthritis, or with another autoimmune disorder. 'The constellation of dry eye with dryness of other mucous membranes - usually the mouth (xerostomia or stomatitis sicca) - or with a systemic connective tissue disease or lymphoproliferative disorder constitutes Sjogren's syndrome. Initial treatment of KCS involves the frequent use of artificial tears and ointments. Punctal occlusion, preservative-free solutions, or the application of moisture chambers to the spectacles may be needed for advanced cases. Mucous filaments on the cornea surface are a source of irritation for some patients with keratoconjunctivitis sicca, especially those with severe disease. These filaments can be treated by mechanical removal or by the use of a topical mucolytic agent, such as 10% N-acetylcysteine. Note, however, that the 20% solution can be toxic.