Sands of the Sahara
Sahara Death Valley Mojave Kalahari. These are the names of just a few of the driest places on the planet. In addition to being geographic proper nouns these words are often used to describe things that are very dry. For many these words are also used as descriptors of their eyes.
Not to be taken lightly
Dry eye syndrome is a problem. A big problem. Estimates indicate that one out of five North Americans may be suffering from dry eyes. Symptoms range from mere annoyance to sheer misery. And dry eye problems are not limited to the elderly. Although dry eye syndrome seems to be more common as one becomes older dry eyes can affect people at any age.
Itching burning watering sandy gritty. These all too familiar complaints are heard numerous times each day by eye doctors as patients attempt to describe their dry-eye-related distress.
The problem is easy to describe but complex as to its mechanism and cause. Simply put no matter what the underlying cause the bottom line is the same: the dry eye sufferer is no longer producing enough tears to keep the surface of the eye adequately lubricated.
If we look at the whole spectrum of dry eye syndrome we d find on one end those individuals whose eyes are only moderately dry. A tear deficiency to these people is no more than a minor annoyance which can be fairly easily alleviated by the frequent use of over-the-counter lubricating eye drops.
On the other end of the spectrum however are those whose severe chronic dryness has resulted in a significant breakdown of the surface of their eyes. These people are reminded of their pain and discomfort nearly every moment of the day and typically find only temporary relief through the constant use of lubricating eye drops and/or ointments. If left untreated severe dry eye can lead to tissue damage and possibly scarring of the cornea of the eye which in turn can lead to irreversible vision threatening conditions.
Is it dry eye or something else?
The symptoms of dry eye syndrome (DES) are often confused with allergies and colds. People with dry eyes often blame their symptoms on ill-fitting contact lenses or sinus problems. DES is actually a collection of symptoms that stems from an imbalance in the quantity or the quality of the tears. These symptoms include dry red gritty and even watery eyes. Often dry eye sufferers report that their eyes feel strained or have the feeling that there is constantly something in their eyes. It s also common to hear patients say they feel as if their eyes were on fire or as dry as Death Valley.
Eyes water: dry eyes?
If my eyes are dry then why are they always watering? This all-too-common question is answered by reminding patients of the dry eye-watering cycle. When eyes are irritated from being dry their reflex is to produce water. In other words the watering they experience is in response to the dryness-induced irritation. These reflex tears are typically evaporated very rapidly which leads to a perpetuation of the cycle.
Ever wonder why your eyelids don t squeak when you blink? All kidding aside it s the tears that keep our eyes lubricated and moist. Without this continued bathing and lubrication by the tears the surface of our eyes would quickly dry out and painfully deteriorate.
A Quick Course in “Tear-ology”
As you might expect instead of being just a single layer of water a healthy tear film is a model of chemical perfection actually consisting of a delicate three layer balance:
- Outer oily layer - because the eyes are open and exposed to the air most of the time this layer functions to reduce evaporation of the tears.
- Middle watery layer - This layer is made up of 98% water and primarily functions to cleanse the front surface of the eye.
- Inner mucus layer - acts to stabilize the tear film on the surface of the eye.
There are many factors that can adversely affect the delicate balance of our three-layered tear film:
- Aging - like most of our body as we age the tear glands don t perform like they used to. Studies have shown that the average seventy-year old has a fifth as much tear volume and twice the natural tear evaporation rate of a typical twenty-year old.
- Environment - exposure to sun wind heaters fans air conditioners high altitudes smoke air pollution sand dust chemicals and pollen can have a negative effect on the tear layer.
- Drugs and medications - over 100 different type of drugs can reduce the amount of tears you have available to bathe your eyes. Examples include antihistamines decongestants diuretics sleeping pills antidepressants certain pain relievers alcohol and medications to treat acne.
- Computer use - whenever we are involved in work that requires intensive concentration we blink less frequently. That s right most people blink about 50% less when staring at the computer reading a book or watching a movie. A reduced blink rate means that the eyes are open more of the time thereby increasing the tear evaporation rate.
- Contact lenses - contact lenses can increase tear evaporation. As a result dry eye is a leading cause of contact lens discomfort.
So what are eye doctors doing for this plagued populace who collectively complains that their eyes sometimes feel as if they are on fire or as dry as Death Valley? No fewer than two dozen brands of artificial lubricants including drops and ointments now crowd the shelves of North American pharmacies all having some measure of success in restoring what the patient once had...a normally functioning tear layer.
Depending on the causes dry eye syndrome can be treated as a temporary problem or a lifelong disease requiring long-term treatment. Either way tears must be or replaced or conserved in order to provide relief.
Enter punctal plugs (conserving tears)
Looking very closely at the lower-inner corners of the eye there is a tiny hole (punctum) at the margin of each lower lid. It s through this hole that our tears drain from the eye down into the throat where they are swallowed.
In cases of persistent dry eye symptoms eye doctors can permanently plug the tear drainage duct. A painless procedure punctal occlusion is performed in your eye doctor s office. It only takes a few minutes to perform but can bring years of relief. Small flexible plugs about the size of a sesame seed are inserted into your tear drainage holes. These soft medical-grade plastic plugs work like a bathtub stopper in your eye by preventing your lubricating protective tears from draining away too quickly. Usually within a half-hour of having plugs inserted in the tear ducts patients have no awareness of the plugs.
If you believe you have the annoying or painful symptoms of dry eye see your eye doctor. With newer and better lubricating drops available and/or with punctal occlusion chances are good that you can find relief.