January is designated National Eye Health Month by the National Eye Institute of the National Institutes of Health. For the past several weeks we’ve discussed how to protect our eyes from the ravages of aging, and from the elements we deal with outdoors. In addition, we discussed some of the myths and facts about eye health. In this final installment I’d like to talk about how the humidity affects our vision, eye comfort and health.
Winter is tough for our eyes and for our furniture because the cold air of the season holds much less water (i.e., humidity). In addition, we heat the outside air up and blow it into our homes and workplaces to make everything nice and toasty warm. The problem here is that the affect of heating causes the air to become even more dry. Our skin feels drier, our eyes tend to burn and itch and blur up with reading or computer work or other indoor activities. This drying effect also dries out our furniture causing it to fall apart but, that’s another story for another part of the paper.
The blink of the eyelid is a simple act that serves many purposes. It moves tear across our eye, pushes debris to the tear duct to be washed from the eye, allows us to reset our fixation and any of a number of other duties. Whenever we are doing close up tasks such as reading, working at the computer, sewing, tying dry flies, painting lead soldiers, etc., etc. our eyes tend to blink much less. As a result they are exposed to the air more and less tear is moved across them for moisture and lubrication.
When tears are not moved across the eye, the surface of the eye starts to dry. Since the tear film is one of the most critical layers for refracting light (check back to your high school Physics textbook for proof) our vision starts to blur. This causes us to blink several times and rub our eyes moving tears over the eye and clearing up the vision. With constant irritation the eyes start to get red and they feel gritty like there is a handful of sand in them. The response from the eye is to pour out “reflex” tears to try and wash the grit out of the eye. This is why dry eye patients have watery eyes.
To protect our eyes and our furniture it is important to keep the humidity in the house at around 50 percent. In addition, frequent use of a good quality lubricating eye drop will help keep the eye moisturized and lubricated.
There are a myriad of eye drop products on the market today. Some are worthless, some are barely adequate but many do a very good job of protecting the eyes from the drying effects of the season. Avoid drops that promise to “get the red out.” These typically work by adding an antihistamine to the solution and causing the vessels on the eye to constrict. When used frequently or over a long period of time the blood vessels become refractory to the effect of the vasoconstrictor and the eye will actually become even more red. In addition, antihistamines have a drying effect on the eye causing a vicious cycle of increased drying to require an increase use of the tears, etc, etc. A good quality eye drop, or artificial tear, will cost a little more but you will be able to tell that it is working and the eyes will be more comfortable.
The important thing is to use the drops frequently. Typically, there is nothing in them that can harm the eye so don’t be afraid of becoming dependent on them or that you are risking your eye’s health by using them.
If you have questions about your eye health e-mail Dr. Barowsky at firstname.lastname@example.org and we’ll try to answer your questions here at Eye-Q.