Multiple reasons why people have dry eyes

Ocular Surface Disease, or dry eye as it is commonly called, is a progressive disease that not only causes short term blur and discomfort, but can also cause blindness over time when not diagnosed and treated properly. It is an eye disease I see daily, if not several times per day.

It's also a problem that I am seeing even in young people more and more. For years, the most common treatment we've had is over the counter eye drops of different thicknesses. As the science on this disorder has increased, we're now able to effectively diagnose the causes and treat them more effectively.

First, let's consider some of the more common symptoms: dry sensation, burning, stinging, scratchiness, excess tearing (watery eyes), itchiness, irritation from wind or smoke, fluctuating vision, contact lens discomfort, etc.

Most often, these symptoms are due to lack of lubrication in the tears. As such, it's like any machine that loses lubrication between moving parts. Friction builds up and causes stress. In the eye, inflammation occurs, causing cell damage and more irritation.

The watery eye is due to the eye's water glands trying to make up in tear volume, what's missing in tear lubricants - it's wet but not slick.

Fluctuating vision is due to a lack of smoothness in the tear surface, similar to getting water droplets on glasses. As light passes through this irregular surface it's focused at different rates in different locations, causing a blurred vision to occur.

Contact lenses require more lubrication than glasses because there are two extra surfaces to lubricate besides the eye and eyelid. When tears are borderline or lacking lubrication, vision and comfort are affected.

Stinging occurs because water is pulled out of eye tissue that normally is structurally solid and nerves are triggered. The pain first increases as more tissue is damaged, then later decreases as nerve endings are damaged, even though the surface area and vision continues to get worse.

In eye surgery, such as cataracts and Lasik, nerve endings are cut that supply brain signals to tell the ocular oil and water glands to lubricate and wet the eye surface-like cutting phone/internet cables so communication doesn't get through.

Next let's look at various other causes of this disease: infection, allergies, dehydration from medications, caffeine, alcohol, tobacco, cholesterol irregularities, computer/cell phone usage, contacts/solutions and lack of sleep.

Infection and allergies activate the immune system, which in turn sends out caustic antibodies to fight off the intruder. The tissue area around the lesion sustains collateral damage which sometimes is worse than the intruder itself. With allergies the intruder can be a change in the immune system itself. Antibodies are fooled to think the body is the enemy and attack good cells.

Cells function properly when they have a specific quantity of water. Too much causes swelling, or edema, too little causes dehydration. Several medications act as diuretics to pull water out of swollen tissue.

But the same medication, as it moves through the body in blood and lymph fluids, can also cause dehydration in the ocular glands that then produce oils and water, different than the natural fluids intended. Caffeine and alcohol are natural diuretics and change the cellular activities just like the before mentioned medications. Finally, remember that not drinking enough hydrating fluids leads to dehydration also.

Tobacco not only causes dehydration, but also forms free radicals in the body. These free radicals in turn change mitochondrial (cellular power packs) activity and some chromosomal regulation.

This leads to cell death from lack of energy and irregular cellular functions. Studies are showing that smoking Cannabis causes redness and dryness to eye surfaces. It seems to cause inflammation, both from the smoke itself and irritants inside.

Cholesterol can be changed by free radicals from fine oils to viscous cloudy, lard-like molecules that clog up the pores, and cause inflammation and breakdown of glands.

Our new computer/cell phone screens put out a blue-violet light (similar to ultraviolet) that causes a lot of glare and sometimes dryness and inflammation. Sometimes people also get mesmerized from this light and don't blink enough.

Recent studies are showing that the top and bottom eyelids have to touch each other to release the oils from their glands. Otherwise, these glands don't release their soothing fluids and the eye gets irritated quickly.

People can acquire an allergy to contact lens materials and/or solutions. Often this happens when people change contact lens solution brands before discarding the previously used contacts.

Contact lenses are also porous to let oxygen through, but plug up with the cholesterol like material over time. That is why cleaning them daily and disposing them at the FDA guideline times is essential to long-term healthy eyes.

Over wearing contacts or wearing contacts not prescribed by an eye care doctor are too tight. That leads to a lack of oxygen and nutrients getting to the eye surface.

Also, waste products aren't flushed out - essentially forming a sewer on the eye surface. This leads to tissue breakdown, dryness and eventually infection with a possibility of blindness.

Lack of sleep affects the eyes in the same way as the rest of the body. Eyes need energy to function and energy supplies have to be resupplied daily, not only to see but also to stay healthy. When people are mesmerized at night by computers/cell phone usage, they don't sleep well and pay the price the next day.

In the next article, I will discuss ways to treat the dry eye problem.

Dr. Scott Borgholthaus is in private practice in Cheney with over 30 years of experience dealing with ocular disorders.