Dry Eye


Dry eye syndrome is one of the most common problems treated by eye doctors. Over ten million Americans suffer from dry eyes. The problem is more frequent in post-menopausal women, patients with rheumatologic conditions and after refractive procedures such as LASIK surgery.
Tears are composed of water, oil and mucus. The water layer is produced in the lacrimal gland, located under the upper eyelid in the outer third. Several smaller glands in the lids make the oily and mucus components of the tear film. With each blink, the eyelids spread the tears over the eye. Excess tears are drained into two tiny drainage ducts in the inner corner of the eye into the nasal cavity. Blockage of these passages produces excessive tearing. Tears are also produced as a reflex response to outside stimulus such as an injury or emotion.

Many diseases can cause dry eye syndrome. One of the most common reasons for dryness is simply the normal aging process. As we grow older, our bodies produce less oil that destabilizes the tear film and increases evaporation. This is more pronounced in women, who tend to have drier skin then men. Many other factors, such as dry or windy climates, air-conditioning or sealing fans, medications such as diuretics and anti-depressants, low fluid intake and cigarette smoke also cause dry eyes. Many people also find their eyes become irritated when reading or working on a computer.

Contact lens wearers may also suffer from dryness because the contacts absorb the tear film, causing proteins to form on the surface of the lens. Certain medications, thyroid conditions, vitamin A deficiency, and diseases such as Parkinson’s and Sjogren’s can also cause dryness. Parkinson’s disease reduces the blinking rate and increases evaporation producing uncomfortable dryness.

The symptoms of dry eye include burning, redness, irritation, blurred vision and excessive reflex tearing. These symptoms are worse in the evenings or after reading or working in the computer.
There are several methods to diagnose dry eyes. The doctor will first determine the underlying cause by measuring the production and quality of the tear film. Examination of the lid margin and special staining of the ocular surface are particularly helpful to diagnose the presence and extent of the dryness.

The treatment of dry eye should be individualized for each patient. Many find relief simply by using artificial tears on a regular basis. Some of these products are watery and alleviate the symptoms temporarily; others are thicker and adhere to the eye longer. When more that four drops are needed daily, preservative-free tears are recommended because they have fewer additives that could potentially induce allergic or toxic reactions.

There are also simple lifestyle changes that can significantly improve irritation from dry eyes. For example, drinking eight or more glasses of water each day, avoiding sealing fans and air condition blowing directly to the patient’s face, using humidifiers at home or at work, using omega-3 fatty acids and avoiding medications that reduce the tear production such as diuretics, antidepressants or sleeping pills may contribute to control the symptoms.

Restasis or Xiidra topical drops may help reduce the inflammatory T-Cell infiltration of the lacrimal gland allowing the gland to produce more of its own tears. Closing the opening of the tear drain in the eyelid with special inserts called punctal plugs is frequently used in moderate cases. They reduce the drainage of the tears allowing the small amount of tears that the patient produces to remain longer wetting the ocular surface. This may be done on a temporary basis with a dissolvable collagen plug, or permanently with a silicone plug. Finally, very severe cases may require the use of autologous serum eye drops that are produced from the patient’s own blood and/or the use of tarsorraphy surgical techniques that reduce the corneal exposure.
Our corneal specialists have done extensive research on dry eye after LASIK. They have identified key cytokines produced under dry eye conditions and have determined how they can be modulated to, in turn reverse the condition and alter the wound healing response.