Have your eyes ever felt irritated, itchy, or gritty? Have they felt as if there were something in your eye when there wasn't anything there? Maybe you have noticed stringy mucous in your eye and occasionally your eye gets blurry. Well, you may have been experiencing the symptoms of Keratoconjuctivitis Sicca or Dry Eye Syndrome.

What is the role of tears?

Tears are needed to protect and lubricate the eye. The tear film which covers the cornea and conjunctiva is composed of three layers. 1) The outer lipid layer (oily component), secreted by the tiny meibomian glands in the eyelids; 2)The aqueous layer, secreted by the lacrimal glands (the main portion being located in the upper nasal corner of the eyelid); and 3) the mucin layer, which is composed of glycoproteins secreted by various cells, which facilitates the adherence of the tear film to the surface of the cornea. All three layers are secreted reflexively when the eyes have dry spots, in order to maintain a constant tear film. This is important because these layers work to perform various functions such as lubricating the eye to decrease friction from the eyelids, supplying oxygen to the corneal cells, washing away debris that gets into the eye and providing antibacterial elements, such as lactoferrin and lysozyme, protecting the eye from infection. In the normal eye the activity of blinking maintains a continuos tear film and prevents the eye from drying. Dryness of the eye may also result from any disease associated with deficiencies of the tear film components or corneal resurfacing mechanisms. In Sjorgren's syndrome, there is deficiency of aqueous tears. There are many medical conditions associated with mucous deficiencies as well, such as Stevens-Johnson's syndrome, ocular cicatricial pemphigoid, vitamin A deficiency, and trachoma. Events which interfere with blinking and with corneal wetting, such as lid paralysis associated with Bell's Palsy or lid scarring, can lead to Dry Eye.

What is Dry Eye Syndrome?

Any inadequacy or instability of any of the tear film components or insufficient interaction between the tear film and the cell surface will result in structural and functional changes on the ocular surface. Areas of dry spots may appear, as the cornea dries some of the corneal epithelium may slough off, especially with the friction of blinking, causing punctate (point-like) defects on the corneal surface. In the latter stages, as more cells from the epithelium continue to shed, epithelium and mucin filaments may form. Do I have Dry Eyes? Many people do. Some common symptoms are itching, a scratchy or sandy sensation in the eye, excessive stringy mucus secretion (mucous filaments), redness, sensitivity to lights, and transient blurry vision. Even a few of these symptoms can point to a diagnosis of Dry eye. Often patients don’t ever complain or notice that their eyes feel dry. Usually on examination, the eyes appears normal. However, on careful slit-lamp examination by an ophthalmologist , one can see a decreased tear meniscus (tear pool), small punctate defects of the corneal epithelium, and occasionally yellow mucous strings. The physician might perform a Schirmer or a Jones test in which he/she measures the amount of tear secretion with filter paper. He/she may analyze the pattern of corneal epithelial defects with special orange flourescein, or rose bengal dyes, or may even measure the osmolarity or the lysozyme level of the tears. Any of these methods can aid the physician in making the diagnosis.

What are the problems associated with this syndrome?

If untreated, dry eyes are usually very irritating and can lead to visual impairment. Some patients go on to develop corneal ulcers, secondary bacterial infections, corneal scars and even perforations. All of these may permanently affect vision.

What is the treatment?

Dry Eye is usually a chronic syndrome and is often difficult to cure completely. This is especially if the patient has had dry eyes for a long time before seeking treatment. Aqueous deficiencies can be treated with artificial tears orsustained-release tear inserts, lubricating ointments at bedtime, and room humidifiers. Mucous deficiencies can be treated with higher-molecular weight ophthalmic solutions. Mucolytics (acetyl cysteine drops) can be used in cases of mucus excess. Treatment with tretinin (Retin-A) has been used to reverse squamous metaplasia of the cornea in some cases of pemphigoid, Sjogren's, and Steven's Johnson Syndrome.

Routine follow up with an ophthalmologist is a vital part of the treatment.

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