Contact Lenses for Dry Eyes
Contact lenses can play a role in dry eyes. Almost 50 percent of contact-lens wearers complain of eye dryness. Contact lenses must remain wet at all times, especially when they are being worn. Most soft contact lenses contain 50 percent water. In order for the lens to maintain its shape and desired optics, it must remain fully hydrated at all times.
Imagine your contact lenses are a sponge. Just as sponges need to be fully saturated to take on their natural shape, your contact lenses do too. As a sponge soaks up whatever moisture it can from a faucet, a contact lens soaks up tears in the eye.
Contact lenses can be the cause of the dryness, or they can also make an existing case of dry eyes worse, and they may cause blurry vision. For patients who suffer from dry eye syndrome, contact lenses may not be the best solution to correct a refractive error. If the lenses do not get enough moisture to maintain their shape for a long enough time, they will become useless and will need to be removed from your eyes.
Dry Eyes and Soft Contact Lenses
Contact lenses are manufactured from one of two types of polymeric materials. Soft contact lenses are made from hydrophilic plastics that contain water. In fact they may contain anywhere from 30–75 percent water, depending on what type of wearing schedule they are designed for. In general, the more water a soft contact lens contains, the more prone it is to dehydration. This is not a desirable attribute, because as water evaporates from the front surface of the lens, the lens reacts by absorbing water from your natural tear film, causing dry eyes.
Dehydration can also contribute to dry eyes. Causes of dryness, such as the heat being on in a room, using a hair drier, exposure to smoke from any source, or exposure to wind can cause soft contact lenses to dry your eyes.
Fortunately, dry eye symptoms from contact lenses are usually temporary and can often be minimized or eliminated by changing lens materials. But for patients who have been wearing their lenses for many years, there may be another cause. The continual rubbing of the lens across the surface of the cornea may result in the loss of the microscopic hair-like structures that exist on the outermost layer of the cornea and assist in keeping the tear film stable. Years and years of chaffing these fine structures can result in poor tear-film stability, resulting in dry eyes. This can occur even if you are comfortable with your contact lenses and wear them successfully for most waking hours.
Dry Eyes and RGP Lenses
Rigid Gas Permeable Lenses are manufactured from polymeric materials that do not contain any water at all. One would think that this would be preferable to the possibility of water evaporating from the lens and causing dry eyes, but the Rigid Gas Permeable Contact Lens polymer is hydrophobic by its very nature, meaning that it tends to repel water, and thus the tear film.
Rigid Gas Permeable Contact Lenses must be specially formulated to enhance their wetting characteristics so that they are compatible with the tear film. Even with these formulations, their surfaces are more prone to drying and creating dry eye symptoms. The problem of chaffing of the fine structures that stabilize the tear film is even greater with Rigid Gas Permeable Lenses because of the rigidness of the lens.
Contact lenses can be a great improvement over eyeglasses for people who are bothered by the cosmetic appearance of eyeglasses or the limitations they impose on certain activities. To ensure a comfortable contact-lens wearing experience you should always be under the care of an eye care practitioner who can make sure that the lens fit and lens materials you have are the best possible choice for you.
Silicone Hydrogel Lenses and Dry Eyes
Silicone hydrogel contact lenses were introduced in 2001. Their high oxygen permeability benefits the cornea. Unlike soft contact lenses, which are mainly composed of water, silicone hydrogel lenses need oxygen to maintain their shape and effectiveness. For people who suffer from dry eyes but do not like the look of eyeglasses and find their soft lenses uncomfortable, silicone hydrogel contact lenses may be the solution due to their oxygen transmissibility. The FDA has approved them for extended wear, and even while sleeping or when the eyes are shut, the cornea still gets enough oxygen to remain healthy. If you are scheduled for a contact-lens fitting soon and have dry eyes, ask your eye doctor about silicone hydrogel.
Ortho-K and CRT for Dry Eyes
Another solution for those whose contact lenses may worsen their dry eye symptoms comes in the form of orthokeratology (ortho-k) and corneal refractive therapy (CRT). Both procedures involve wearing special gas permeable lenses while sleeping. These lenses gradually reshape the cornea to correct nearsightedness. The procedures do not require you to wear the lenses during the day, nor do you need to wear contact lenses or eyeglasses to see clearly. Ortho-k and CRT may eliminate the dry eye symptoms caused by contact lenses.
Because the lenses used in these procedures are gas permeable, they do not need as much moisture as soft lenses do to remain comfortable and effective. Plus, you wear them while sleeping, or while your eyes are closed, decreasing the chances of your lenses or eyes drying out due to tear evaporation.
Common Contact Lenses for Dry Eyes
Here is a list of contact lenses specifically designed to counter dry eyes.
|Contact Lens||Quantity||Average Cost|
|Proclear Compatibles||6 pack||$30.00|
|Ciba Night & Day||6 pack||$60.00|
|Extreme H2O||6 pack||$25.00 to $40.00|
|Acuvue Oasys||6 pack||$30.00|
|1-day Acuvue TruEye||90 pack||$45.00|
|Dailies AquaComfort Plus||90 pack||$40.00|
Complications of Contacts and Dry Eyes
As noted above, contact lenses can either be the cause of dry eyes or they can worsen the existing symptoms of dry eye syndrome. For people who already suffer from the symptoms of dry eye (burning sensation, gritty feeling, eye pain, redness, excessive tearing, and an intolerance to lens wear), the wrong type of contact lens may cause extreme discomfort and they may interfere with normal daily tasks such as driving, reading, and working on the computer. Depending on the material used, your lenses may take a long time to get used to. They may be uncomfortable during the adjustment period, and dry eye symptoms may not resolve until after the adjustment has been made.
Benefits of Contacts and Dry Eyes
For people who suffer from dry eye syndrome, there are solutions in the form of contact lenses. Depending on your needs, newer materials such as silicone hydrogel may make it possible to wear contact lenses without dry-eye symptoms. In the chart above are several different brands that are specifically designed for people with dry eyes. Some of these lenses provide comfort and visual clarity for up to twelve hours a day, even when exposed to harsh environments. They can be found in a range of prescription strengths to correct refractive errors such as presbyopia, myopia, and astigmatism. While some are designed to be worn for extended periods, others are meant to be discarded after one use.
Talking to Your Eye Doctor
Here are some questions to ask your eye doctor about contact lenses and dry eyes:
- Are my lenses causing my dry eyes?
- What options do I have for contact-lens material?
- Are there any over-the-counter products that can help relieve my dry eyes while I am wearing my contact lenses?
- Do you offer contact lenses for dry eye sufferers?
Did you know … eye dryness is the #1 reason why people discontinue wearing their contact lenses?
- J. Anshel, MD “Smart Medicine for Your Eyes” (SquareOne Publishing, 2011) 332; J. DiGirolamo, MD “The Big Book of Family Eye Care” (Basic Health Publications, Inc. 2011) 118-120
- Google Product Search, Contact Lenses for Dry Eyes, http://www.google.com/prdhp?client=firefox-a&rlz=1R0GGLL_en&tab=wf