10 CRAZY THINGS CONTACT LENSES CAN DO

10 Crazy Things Contacts Can Do
By Maria Trimarchi, How Stuff Works, 3 March 2014.

About 36 million people wear contact lenses in the U.S. alone, and that number grows every year - the idea of using a small, soft lens to enhance how we see is hardly a new concept. But other than correcting refractive errors (the kind of vision problems caused when light doesn't properly bend as it enters the eyes, resulting in blurry images), what have your contact lenses done for you lately?

What if contacts could help people with diabetes monitor their blood sugar levels? Or cure blindness? Or show you the newest e-mail to hit your inbox? Contacts can do some crazy things; let's start by talking about how they can turn your brown eyes...hey, is that glow in the dark?

10. Cosmetic Contact Lenses

The cat-eye contact is a Halloween staple. To protect the health of your eyes, be sure to get any special

effects lenses through a medical professional.

Contacts can do more than turn your brown eyes blue. Decorative (cosmetic) contact lenses can make your eyes glow in the dark, splash your favourite team's name or logo across your eye, or, if you're going for gold, give you the eye of the tiger.

As fun as they may be, though, decorative contact lenses are associated with eye injury, such as corneal scratches, and if you're not careful, that kind of eye damage may cause infection and even blindness. The FDA regulates contact lenses and recommends you always get fitted for lenses, get a prescription (even if you don't wear corrective lenses) and buy your contacts from a medical professional for the safest results.

9. Halt the Progression of Near-sightedness in Children

Orthokeratology may be able to slow vision degeneration.

There are three basic types of contact lenses: hard lenses (developed in the 1940s, and now pretty much obsolete), soft lenses (introduced in the 1970s, and the most popular style worn today) and, since the late-1980s, rigid gas permeables (GP contacts). Fewer than 10 percent of all new contact lens wearers choose GPs, but their popularity is growing. And, as it turns out, they may do more than correct your vision; they may also help correct myopia, or at least slow its progression.

Myopia (near-sightedness, which is when objects at a distance appear blurry) is a vision problem that affects as many as 30 percent of Americans; it happens when your eyeball is too long (oval-shaped) in relation to your eye's cornea and lens. It commonly begins in childhood and usually continues to progress through adolescence; and, while the research isn't complete, the rate of its progression may be slowed with GP contact lenses. GPs show promise in arresting myopia's development in 8- to 12-year-old patients who wear the lenses to correct the problem. How? Orthokeratology, a method that uses specially-designed GP lenses worn at night to reshape the wearer's cornea. It's a temporary change, but one that's effective about 30 percent of the time [source: Family EyeCare Center].

8. Simulate Simultaneous Vision

People with multi-focal correction needs can skip carrying around multiple pairs of glasses or wearing

bifocals. Contacts can take care of it.

No two pairs of eyes see alike, and for that matter, your own two eyes may not have the same vision. Refractive errors such as near-sightedness (myopia), farsightedness (hypermetropia) and astigmatism are all common vision problems, and often run in families. In addition, if you're over the age of 40, you may find you're beginning to need a pair of readers for up-close vision. This is an age-related vision problem called presbyopia (which is often confused with farsightedness because they have similar symptoms despite different causes). And that's just the beginning.

While it's common to wear corrective contact lenses for multi-focal correction (when you need help seeing at varying distances) such as bifocals, that doesn't mean you'll need to ditch your contacts and go back to glasses [source: American Academy of Ophthalmology]. Your average contact lens will correct a single problem, such as seeing things at a distance, but multi-focal contact lenses can provide what's called simulated simultaneous vision, which means they'll help you see far away and close-up, whether it's reading highway signs in the distance or your computer screen, as well as the small print on your tablet or smartphone. This type of lens may also, in the future, become the key to hands-free augmented reality: A wearer could simultaneously focus on her surroundings and incoming digital information from a Google Glass-type headset.

7. Improve Athletic Performance (Maybe)

Could an amber tint in a contact lens sharpen an athlete's vision? Maybe.

Adding an amber tint to contact lenses may help turn up the contrast while turning down the glare, which should theoretically make baseballs, footballs, hockey pucks - you name it - easier to see. That would theoretically mean the athlete's response time could improve.

Amber-tinted contact lenses aren't yet proven, and researchers disagree on whether or not wearing the lenses translates into any significant performance improvement. Some studies find that the lenses may actually reduce the eye's sensitivity, while others find no difference or only a slight improvement in athletes who have a mild astigmatism or a need for a mild refractive error correction.

6. Telescopic Vision

Imagine the power of a telescope embedded in your contact lenses.

Just as if you were looking through a telephoto camera lens or a telescope, there are contact lenses able to magnify what you're looking at by 2.8 times. Yes, finally your very own superpower! Well, it's more about correcting poor vision than seeing like Superman.

When used with a pair of specially designed 3-D glasses, these gas permeable contacts are intended to help people with age-related macular degeneration see normally and focus in on small details without relying on biopic telescope low vision aids, which can be bulky or awkward.

5. Prevent Glaucoma-induced Blindness

Regular vision check-ups - with glaucoma screenings - can keep you from being one of the millions of

people who have glaucoma and don't know it.

More than half of the 2.2 million Americans who have glaucoma don't know it; there really aren't any obvious symptoms until the condition has already been allowed to develop for years (or decades, in some cases).

Glaucoma is caused by an elevated pressure in your eye. It's a condition that everyone is at risk of developing, that has no cure and that's the second leading cause of blindness (if it's not properly treated - and even when it is, 10 percent of patients will still lose some or all of their vision) [source: Glaucoma Research Foundation].

Enter the contact lens.

Experimental contact lenses monitor subtle changes in the eye over a month's time and deliver pain-relieving and eyesight-saving medication to decrease fluid production and lower pressure in the eye. This is instead of the traditional eye drops (which the eye absorbs less than 7 percent of) [source: Children's Hospital Boston]. Oh, and they'll also correct your vision at the same time, if you need it.

4. Therapeutic Bandage

Contacts can serve as bandages, protecting eyes after injury or surgical procedures, and even

administering medications.

Not only can contact lenses deliver sight-saving medication to glaucoma patients as we just discussed, they can also act as therapeutic bandages after eye surgeries such as photorefractive keratectomy (PRK) or LASIK surgery. They can also offer bandage care for other eye diseases or injury such as corneal ulcers, chronic eye infections or chemical burns.

These special soft contact lenses are made of silicone-hydrogel hybrid polymers, which supply oxygen and moisture to the eye. They help promote tissue healing, reduce irritation, increase corneal protection during the healing process and deliver antibiotics and pain medications directly to the affected area.

3. Create Personal Virtual Displays

Your contact lens could eventually show you augmented reality information and text alerts.

Hold up; you too may soon be able to have your very own personal Terminator-style augmented reality display - yes, right on your eye. Receive a new text message? Your high-tech eye will show it to you. As well as driving directions, holographic images, news and any other information. How? Through your contact lens, of course.

Bionic contact lenses are showing promise in the laboratory, but they're still prototypes and aren't yet available for you and me. These lenses are rigged with small, thin electronic circuits and LEDs and are powered wirelessly to deliver small, real-time bits of information straight to your line of sight. The question now isn't if they can be made, but how much can actually be displayed on a human eye.

2. Monitor Your Blood Sugar Levels

Pricking a finger to test blood glucose could be a thing of the past.

Just like fitness bracelets or other gadgets that track your steps or your calories, wearable technology is moving from your wrist to the surface of your eye. Google is working on a smart contact lens, not to give you directions or display your e-mail, but to monitor and report your blood sugar levels.

Google's smart contact lenses are based on the idea that you don't need to prick your finger to test your blood sugar level when you could instead monitor your levels through your tears. The prototype is a soft lens designed so your tears flow through a pinhole and over a glucose monitor. The results of the reading are transmitted from an antenna embedded within the lens to a handheld device, and it's all powered with wireless RFID technology.

1. Cure Blindness

Can blindness be reversed through contact lens therapies? Scientists are working on it.

Scientists are using stem cell-infused contact lenses to restore sight to people with corneal damage and related blindness.

While still experimental, the process starts with harvesting limbal stem cells from the eyes of the patient or a donor). These are special cells the body naturally produces whenever it needs to repair a minor corneal problem with your eye, such as damage from dust, debris and even blinking; if you don't have enough of them, your vision becomes compromised. The collected limbal stem cells are then grown directly on contact lenses. When worn by a patient with corneal damage, these specially coated lenses transfer the stem cells from the contact to the cornea, where they repair and regenerate tissue. Researchers in Australia found that two out of three legally blind patients who tried the contacts regained some sight. And the third? The third patient passed the vision test of a driving exam [source: Smith].

Author's Note: I think my favourite take-away fact about eyes discovered while researching and writing this article is that healthy human eyes see at a resolution of just about one megapixel (not that we actually see in pixels; this is just an equivalent). So that new Ultra HD TV you've had your eye on? It turns out your eyes really won't be able to tell the difference between that and the high-def TV you already have.

Related Articles:

1. How Artificial Vision Will Work

2. How Contact Lens Displays Work

3. How Vision Works

More Great Link: National Eye Institute: How We See

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Top image: Contacts can do so much more than correct your vision, and new applications are constantly in development. Credit: © AndreyPopov/iStock/Thinkstock.

[Post Source: How Stuff Works. Edited.]