A: Dry eye syndrome is a catch-all term referring to abnormalities of the tear film which normally covers and protects the surfaces of the eyes. Dry eye syndrome causes pain and discomfort (sometimes severe) and blurry vision, and the human tear film is complex, consisting of an aqueous (watery) layer with a thin lipid (oily) layer on top to retard evaporation and a thin mucous layer underneath to help it adhere properly to the surface of the eye. Each of the three layers has a different source, and disruption to any one or more of the three tear film layers may interfere with the process of routine lubrication of the eye surface, causing one of the conditions that fall into the "dry eye" bucket.

A: There are many different causes of the conditions collectively referred to as dry eye syndrome. These include:

• Systemic diseases (e.g. Sjögrens, Stevens Johnson Syndrome, diabetes)
• Eye diseases (meibomian gland dysfunction, blepharitis, )
• Medications
• Aging
• Long-term contact lens use
• Computer use
• Environmental and behavioral factors (e.g. dry climates, contact lens wear)
• Laser eye surgery (e.g. LASIK)

A: Dry eye is not necessarily what it sounds like - it is not just about the eyes feeling dry. Here are some examples of symptoms of dry eye:

• Eye fatigue
• Redness
• Itching
• Irritation
• Scratchiness
• Discharge
• Feeling that there is something in the eye
• Burning sensation
• Watery eyes (from reflex tears)
• Blurry vision
• Light sensitivity

A: The most frequently used tests for dry eye are the Schirmer's test (where a small strip of paper is placed in the eye), which is intended to measure aqueous tear production, and the tear break-up time test, which can help doctors identify tear film instability. There are also much more sophisticated tests that can be done, but none of these are normally available through your ophthalmologist or optometrist.

At the Zone we are strong proponents of a self-diagnostic survey called the Ocular Surface Disease Index, a scientifically validated 20-question survey which produces a score based upon commonly recognized symptoms and their severity and helps patients communicate their condition to their doctor.

A: The treatment of dry eye varies greatly, depending on the nature, cause and severity of the condition. Broadly speaking, in moderate to severe cases, treatment is not a question of a "cure" but rather of managing the symptoms so as to (a) reduce the discomfort and life impact to a tolerable level if possible and (b) protect the eyes and prevent injuries that can occur as a result of chronic or excessive eye surface dryness.

Most patients use one or more artificial tear supplement products, and many patients use punctal plugs or have their tear drains cauterised. These constitute the traditional "plug'n'drop" treatment. After this, there are medical treatments (prescription drugs and in some cases surgery), alternative or complementary therapies, and a variety of "tips and tricks" and lifestyle modifications adopted by dry eye patients. See below for more about treatments in any of these categories.

Many dry eye patients find that the combination of treatments and therapies that is most effective at keeping their symptoms under reasonable control is unique to them, and may vary over time or during different seasons. Dry eye patients are often in pursuit of additional strategies to better manage their condition.

A: It is essential to the health of the eye that the eye surfaces remain lubricated. A dry eye ocular surface results in eye injuries (erosions and abrasions) which can progress to ulceration in severe cases, and can seriously compromise vision.

Nearly all dry eye patients, irrespective of what other treatment(s) they may be using, need to use eye lubricants to protect their eyes and to reduce discomfort. For daytime use, this means artificial tear supplement. Some patients use thicker products, such as gels or ointments, at night

A: The eyes have four drains, called punctal, through which tears (which are constantly renewed) exit. These are in the lower and upper corners of the eyelids nearest the nose.

For patients whose dry eye symptoms are caused primarily by a deficiency in the water (aqueous) part of their tears, stopping the drains (called punctal occlusion) can sometimes help improve the symptoms. There are two ways to do this: using small plugs, or permanently sealing the openings with cautery. There are also temporary collagen plugs, which dissolve by themselves, which can be placed in order to test the likelihood that silicone plugs or cautery will be helpful and will not result in tear overflow (epiphora).

A: For many patients, part or all of the problem causing their dry eye conditions may be a deficiency in the oily part of their tears which is supposed to slow evaporation of the tears. This can be treated by improving the secretions from the meibomian glands. Some prescription drugs (including oral antibiotics) may improve gland function, but they may carry unacceptable (to you) side effects. Nutritional supplements such as flaxseed oil or fish oil may also help. However, for many patients lid therapy may be a more acceptable or more immediately effective method. Lid therapy involves improving eyelid hygiene and manually working on the glands to get those juices flowing

A: There are a number of prescription drugs available which are used sometimes in the treatment of dry eye, both systemically and topically. Systemic antibiotics in the tetracycline family are sometimes prescribed for patients whose primary problem is with the lipid layer of the tear film (as a result of poor functioning of the meibomian glands). The pharmaceutical companies are increasingly developing prescription drugs specifically for dry eye.

A: A significant factor in dry eye for many patients is the function of their meibomian glands, glands in the lower and upper eyelids which produce the oily (lipid) layer of the tear film that is so important in making sure tears don't evaporate too quickly. Lid therapy comprises techniques to improve the function of the meibomian glands, make sure the secretions are flowing properly and improve eye comfort.

A: Environmental factors play a significant role in dry eye symptoms. Many patients find they need to protect their eyes, particularly at night (to prevent excessive evaporation while they are sleeping) and outdoors, especially in dry climates or windy weather.

A: Dry eye patients are often recommended to take flaxseed oil. But the potential benefits of vitamin supplements do not stop there.

A: Unfortunately, many patients with severe dry eye or whose dry eye is the result of particularly challenging conditions such as nerve damage may find that no combination of known treatments gives them sufficient relief. Pain management techniques may then prove useful. These range from simple things like hot or cold compresses for short-term relief to pain drugs (though these are usually eschewed because of complementary pain treatment such as acupuncture or herbal therapy.

A: There are several reasons chronic dry eye can lead to clinical depression. Dry eye patients need to be on the alert, understand why they may be susceptible to depression and why this is normal (and not a sign of weakness), and speak with both their eye doctor and their GP about their concerns.

First, the pain can be constant and severe. Most people who have never had dry eye or a serious eye injury have no conception how much pain the eyes are capable of producing. It can drive one to distraction. When chronic, it is a constant drain on one's coping resources. Second, there is a direct and sometimes dramatic impact on lifestyle. Outdoor activities, for example, may become impossible, because of irritation from air/wind and/or because of extreme light sensitivity. Third, appearance can be affected. Chronically red eyes are unsightly. And women may find they can no longer tolerate cosmetics near their eyes. Finally, there may be special factors at play depending on the individual cause of dry eye syndrome; for example, patients who have undergone elective laser eye surgery but were not properly screened before surgery or were not aware of the risk of permanent dry eye as a complication may find themselves preoccupied with bitter feelings.