In a normal eye, the tear film covers the cornea and the exposed conjunctiva, providing nutrients, and acting as a protective barrier. But in keratoconjunctivitis sicca, which is known as dry eyes syndrome, there is an inflammation of the cornea and conjunctiva associated with dryness of the eye. It occurs commonly as part of Sjogren’s syndrome.
Sjogren’s syndrome is an immune system disorder. in which the body’s immune system attacks its own cells, which produce saliva, and tears.
Symptoms of Keratoconjunctivitis Sicca
Keratoconjunctivitis sicca is characterized by:
- Decreased lacrimal secretion, which causes the dryness of the eye.
- Conjunctival hyperemia, which is an increasing amount of blood in the vessels, and
- Itchy eyes due to the gritty feeling of dry eyes.
It is diagnosed by Schirmer’s test. This test determines whether the eye produces enough tears to keep it moist.
The test is conducted by a doctor, by placing a filter paper in the lower eyelids of both eyes and then the patient closes the eyes. After five minutes, the doctor removes the filter paper then assesses how far the tears have traveled on the paper.
It is considered negative or normal. when there is more than 10mm of moisture on the filter paper in 5 minutes but if less than 10mm in 5 minutes, it is considered abnormal or positive.
Management of keratoconjunctivitis sicca include:
1. Use of drops. which serves as tear substitutes, such as hypromellose, sodium chloride, and sodium hyaluronate.
Also, some gels and ointments can also be used instead of drops.
2. Topical ciclosporin, which is an immunomodulatory agent, increases the production of tears, by inhibiting the T-cell activation pathway. But it should not be used as a first-line.
3. Scleral lenses can also be used but they are expensive.