Corneal Hypoxia: Dangers Of Oxygen Deprivation
Does It Really Matter If You Leave Contact Lenses In Longer Than The Prescribed Wearing Time?
The earliest versions of contact lenses were made of very thin glass. Think about that for a moment: a small piece of glass was placed directly on the eye. If you have any imagination at all, the possibilities of permanent and painful damage are all too obvious. For someone to take this sort of risk, the potential benefit must have been great. Because we enjoy the advantages that are the result of early trial and error, as well as modern innovation, we sometimes take these tiny lenses for granted. This is what leads to problems like corneal hypoxia and one of the reasons that regular eye care exams are so important.
Most people alive today do not know what it was like to not have the option of replacing eye glasses with contacts. Few have struggled with the difficulties of the original hard lenses that took lengthy adjustment periods and were prone to infections and injuries when foreign particles in the eye were aggravated. Oxygen deprivation was a problem in those days because there was a solid barrier on the cornea. This was alleviated with the arrival of soft lenses and gas permeable rigid lenses that allow air to reach the eyes. Seemingly, all of a sudden, contacts were easy to get, comfortable and could be worn for extended periods of time, even overnight.
Sounds like a total success story, doesn’t it? In many ways it has been. However, there is balance that plays out in the eyes, as it does in most areas of the body. Just because the latest types of contact lenses may come in a box that says it is alright to wear them for a month and that it is not necessary to take them out when you sleep, this does not mean that it is necessarily the best practice for optimum eye health. Other than during times of war or perhaps while the country was in the grips of the Dust Bowl in the 1930s, there has likely never been a time when there were more contaminants in the world. Whether in the air we breathe or surfaces we touch, potentially harmful substances are constantly present that, if introduced to the eye, can cause serious problems. Consistent and thorough cleaning of lenses is crucial.
Not adequately keeping contacts clean is not the only concern. Even with new oxygen permeable materials, there is still a very real danger of corneal hypoxia, which is when the cornea, the clear outermost layer of the eye, does not get enough oxygen. Some designs are more oxygen friendly than others but even the best still allow only a tiny fraction of access compared to not wearing lenses at all. Adding to that by sleeping with the lenses in only exacerbates the situation.
Symptoms of oxygen deprivation in the eyes includes blurred vision, burning, excessive tearing and a scratchy feeling, almost like there is sand in the eye. Mild cases typically result in swelling in the epithelial layer of the cornea and temporary blurred vision. More severe hypoxia can lead to the death of epithelial cells.
The moral of this story is that contact lenses are tiny miracles capable of restoring near perfect vision and should not be taken for granted. Be diligent with proper care and, at the first sign of a problem, consult with your eye care professional.
If you are having any issues with contacts, Long Island Ophthalmic Concepts is ready to provide high-quality, comprehensive care in our four convenient Long Island office locations. For more information about contacts, or if you have other questions or comments, please call the office most convenient to you, Bellmore, Great Neck, Little Neck or Huntington. If you would like to schedule an appointment, simply click here to go to our online scheduler.