Your eyes are pretty amazing. From the moment you open your eyes in the morning to the moment you drift off to sleep your eyes are busy working for you – working together with your brain they do some fantastic things.
They let you read a book, watch a movie, check out a rainbow, see the expressions on the faces of your friends and family and watch out for a softball heading your way. It’s important to remember that the eyes you have will be yours forever and you need to learn about them and treat the right! “Treat them right and they’ll never be out of sight!”
Think of the eye as a camera. The front part of the eye has the magnification and the back part has the film.
Your eye works very much like a camera. Light enters the eye, first passing through the outer clear layer of the eye, called the cornea.
Through the cornea, the light next passes through the pupil that is a passage way to the back of the eye. The pupil gets bigger to allow more light in (when there’s very little light) and smaller to allow less light in (when there’s a lot of light).
How does the pupil know to get bigger or smaller? That’s the job of the iris. The iris is the colored part of your eye, and it controls the pupil’s size.
Once the light passes through the iris, it next hits the lens. The lens puts the light rays into focus and sends it to the retina. But before it hits the retina, it has to pass through the vitreous humor – a colorless mass of jelly – like material behind the lens. The light passes through this material, traveling to the retina.
The retina is the innermost layer of the eye. Think of the eye as a camera. The retina, then, is the film in the camera which captures the image. The funny thing is that the image on the retina appears upside-down, backwards, and 2-dimensional. But when we think about how we see things, they’re always right-side-up and 3-dimensional. Something else has to happens before this the journey is over…this light-information has to be is sent to the brain. The retina contains light-sensitive cells called rods and cones. These cells connect to the brain through a very important nerve at the back of the eye called…
This nerve is the brain’s messenger, sending the image to a place in the back of the brain called the occipital lobe. It’s at this point that the brain is able to switch that backwards, upside down, 2-dimensional image into its correct form. Here the 2-dimensional image becomes 3-D.
How is does your brain able to turn a 2-dimensional image into a 3-dimensional image? You need to remember that you have two eyes, each carrying this light information to the brain from 2 slightly different angles (your eyes are several inches apart, and that gives each eye a slightly different view on the world). Each eye – several inches apart carries this light information to the brain from two slightly different angles. When the brain receives both of these 2-dimensional images, it combines them together into one 3-dimensional image, allowing you to see the world in 3D!
Your eyes have their own special bathing system to wash away things that can hurt or irritate them. Above the outer corner of each eye are the lacrimal glands, which make tears. Every time you blink your eye, a tiny bit of tear fluid comes out of your upper eyelid. It helps to wash away germs, dust, or other particles that don’t belong in your eye. It also keeps your eye from drying out. Then the fluid drains out of your eye by going into the lacrimal duct (this is also called the tear duct).
You can see the opening of your tear duct if you very gently pull down the inside corner of your eye. When you see a tiny little hole, you’ve found the tear duct.
Sometimes your eyes will make more tear fluid than normal to protect themselves. This may have happened to you if you’ve been poked in the eye, if you’ve been in a dusty or smoking area, or if you’ve been near someone who’s cutting onions. And how about the last time you felt sad, scared, or upset? Your eyes got a message from your brain to make you cry, and the lacrimal glands made many, many tears.
Did you know that 9 out of 10 eye injuries can be prevented with proper care? Eye injuries usually happen at home and school and often during sports and hobby activities. Make sure you practice prevention!
Injuries can happen easily so be careful. You have to really think about what you are doing. Wouldn’t it be awful if someone’s eyes were hurt and it was your fault? Here are some ways to help and make sure you don’t hurt anyone else’s eyes.
Because your eyes are so precious you really need to take special care of them.
Lots of people have problems with their eyes. You can miss a lot of things if you can’t see well. Sometimes you don’t even know you have a problem at first because you don’t know that everyone else sees things differently. If you are worried or not sure if you may have a problem with your eyes, tell your mom or dad or a teacher. Here are some things that might mean that you are not seeing as well as you could:
The human eye is like a camera that collects, focuses, and transmits light through a lens to create an image of its surroundings. In a camera, the image is created on film.
In the eye, the image is created on the retina, a thin layer of light-sensitive tissue at the back of the eye. Like a camera, the human eye controls the amount of light that enters the eye. The iris manages the amount of light passing through the pupil. It closes up the pupil in bright light and opens it wider in dim light. The cornea is the transparent, protective surface of the eye. It helps focus light, as does the lens. When light enters the eye, the retina changes the light into nerve signals. The retina then sends these signals along the optic nerve, a cable of more than 1,000,000 nerve fibers, to the brain. Without a retina, the eye can’t communicate with the brain, making vision impossible.
So what’s the cause of many common vision problems? Often, eye shape is the culprit. Someone with perfect 20/20 vision has eyes that are basically round like a baseball. Someone who needs corrective lenses to see usually has eyes that are shaped differently.
Myopia (pronounced: my-o-pee-uh), or nearsightedness, is one of the most common problems teens have with their eyes. When a teen has myopia, he or she is unable to focus properly on things that are far away. People with myopia have eyes that are a little longer than normal, measuring from the front of the eyeball to the back. This extra length means that light focuses in front of the retina (the part of the eye that receives images and sends them to the brain) instead of on it, and that affects vision. Glasses or contacts can easily correct this problem.
Hyperopia (pronounced: hi-puh-ro-pee-uh), or farsightedness, is another problem. People with hyperopia have trouble focusing on things close up because their eyes are too “short” from front to back. In people with hyperopia, light focuses behind the retina instead of on it, causing blurry vision. Someone with significant farsightedness will need glasses to correct his or her vision. But here’s an interesting fact: Many babies are born farsighted! Their eyeballs get longer as they grow, and most of them outgrow the condition.
Another condition where the eye is differently shaped is astigmatism. Here, the eye is slanted at the front, shaped more like a football than a baseball. To be able to see well – either close up or far away – the person needs contact lenses or glasses.
Once people reach 18 and their eyes are fully grown and less likely to change, some people choose to have refractive surgery to correct myopia so they don’t have to wear contacts or glasses anymore. Refractive surgery is a procedure – usually done with a laser – that reshapes the eye to change the way light enters it and forms an image, allowing a person to see better.
If you need glasses or contact lenses, you can follow a few tips for the best results. When you pick out glasses, remember as a general rule that smaller frames will probably suit you better. The larger the frame, the more distortion you’ll have, and you may not be able to see as well.
If you get contact lenses, follow your doctor’s orders exactly when it comes to cleaning them, how many hours you can safely wear them, and when you should replace them. If you don’t, you could develop serious infections or ulcers in your eye that are painful, difficult to treat, and may need months of medication or even surgery.
Eyes and vision are something no one wants to be without. To keep them working for you for many years to come, protect them now and take the best care of them that you can.
If you have a red eye, pain in an eye that doesn’t go away within a short period of time, or at any time have had changes in your vision, then it’s time to have your eyes checked by a specialist.
If you get any small foreign objects in your eye, such as sand or sawdust or metal shavings, don’t rub it. Flush your eye for several minutes with lukewarm water (it may be easiest to do this in the shower). If it still feels as though there is something in your eye, then be sure to see an eye specialist.
If you’ve been hit in the eye and it looks strange or appears to be bleeding, or if you have changes in or lose your vision, go to a hospital emergency department right away to be checked out.
One of the most common eye injuries for teens is a scratched cornea, which is usually related to wearing contact lenses or playing sports. With a scratched cornea, it may feel like something is in your eye when there’s really nothing there. Your eye may get red and irritated, produce lots of tears, and be overly sensitive to light.
If you think you have any kind of eye injury and you wear contact lenses, stop wearing your contacts until you see an eye specialist. Wearing contact lenses if you have an eye injury could damage your eyes more or cause an infection to develop. Don’t worry – if your cornea is scratched, it usually will heal after a week or 2 of medicated eye drops and not wearing your contacts.
You can also protect your eyes by preventing infections that could harm them. Conjunctivitis, which is also sometimes called pinkeye, is an eye infection that can be caused by a virus, bacteria, an allergic reaction, a chemical, or an irritant (something that gets in the eye). Conjunctivitis that is caused by germs like viruses and bacteria can easily pass from person to person. After you shake hands with someone who has a bad cold and pinkeye, for instance, you could spread the infection to your own eye by touching it with your hand.
You may think you’re too old to get the eye infection conjunctivitis (pronounced: kun-junk-tih-veye-tus), commonly known as pinkeye. It’s usually associated with young children, probably because it’s contagious and tends to sweep through preschools and playgrounds. But even adults get conjunctivitis.
Conjunctivitis is an inflammation of the conjunctiva, the tissue covering the eye and inner surface of the eyelid. Conjunctivitis can be infectious (caused by bacteria or viruses) or noninfectious. The common types of noninfectious conjunctivitis are allergic conjunctivitis (caused by an allergic reaction) and irritant conjunctivitis (caused by anything that irritates the eyes, such as air pollution or chlorine in pools).
When most people talk about conjunctivitis, though, they are usually referring to the infectious kind. Infectious conjunctivitis is often caused by the same bacteria and viruses that are responsible for colds and other respiratory infections, including ear infections, sinus infections, and sore throats. It’s also possible for the same types of bacteria that cause the sexually transmitted diseases chlamydia and gonorrhea to cause conjunctivitis. If a person touches an infected person’s genitals and then rubs his or her own eye or touches a contact lens, the infection can spread to the eye.
In most cases, infectious conjunctivitis causes only minor problems and may affect one or both eyes. Most cases of conjunctivitis won’t damage your eyes or your vision when treated promptly. In very rare instances, though, conjunctivitis can cause permanent damage or even blindness, so be sure to see your doctor if you experience any symptoms.
The incubation period (the length of time between when a person gets infected and when the symptoms actually appear) will depend on what is causing the infection. The incubation period for conjunctivitis ranges from a couple of days to a couple of weeks.
The most common symptom of conjunctivitis is discomfort in the eye – a person’s eyes may feel itchy or gritty. There often will be some discharge from the eyes and pain, redness, and swelling of the conjunctiva. Because the eye can look very pink or red, the infection is often called pinkeye.
It can be hard to tell whether the infection is caused by a virus or bacteria. In general, the discharge associated with viral conjunctivitis is watery, whereas it will be thicker and more pus-like when the infection is caused by bacteria. When you wake up in the morning, your eyelids may be stuck together (don’t be alarmed, though – cleaning your eyes with a warm washcloth will loosen the dried crusts).
Conjunctivitis that’s caused by bacteria is contagious as soon as symptoms appear and remains contagious as long as there is a discharge from the eye – or until 24 hours after antibiotics are started. Conjunctivitis that’s caused by a virus is generally contagious before symptoms appear and can remain contagious as long as the symptoms last.
Because infectious conjunctivitis is highly contagious, it’s a good idea to wash your hands after interacting with friends, family members, or coworkers who have the infection. (It’s a good idea to wash your hands regularly, anyway!) Don’t share potentially infected items like washcloths, towels, gauze, or cotton balls. This can be difficult among family members, so just do the best you can. If you have conjunctivitis, it’s important to wash your hands frequently, especially after touching your eyes.
It’s also a good idea not to share cosmetics, especially eye makeup. Conjunctivitis-causing bacteria can hang out on beauty products, so avoid using the testers at makeup counters directly on your eyes. And if you’ve already battled a bout with conjunctivitis, throw away all your eye makeup and splurge on new stuff (but don’t start using your new products until the infection is completely gone).
If you wear contact lenses and you’ve been diagnosed with conjunctivitis, your doctor or eye doctor may recommend that you don’t wear contact lenses while you have an eye infection. If you have conjunctivitis, clean your lenses carefully. Be sure to disinfect the lenses and case at least twice before wearing them again. If you wear disposable contact lenses, throw away your current pair and use a new pair.
Because it can be hard to tell which kind of conjunctivitis a person has, it’s a good idea to visit a doctor if your eyes are red and irritated. The doctor may also check to see if you have an ear infection, which can sometimes happen when a person has conjunctivitis.
Bacterial conjunctivitis is usually treated with prescription antibiotic drops or ointment. Drops – the form of treatment most commonly prescribed for teens – are used up to four times a day. They don’t hurt, although they may cause a brief stinging sensation. The typical length of treatment is one week. Even though your eyes should feel and look better after a day or two, it’s important to use the drops for as long as the doctor has prescribed. The infection may come back if you stop too soon.
If a doctor thinks a virus is causing your conjunctivitis, antibiotic drops will not help. The eye infection will get better as your body fights off the virus.
Placing cool or warm packs or washcloths over the infected eye (or eyes) can help. You can also take acetaminophen (such as Tylenol), if necessary. It may be helpful to clean the infected eye carefully with warm water and fresh, clean gauze or cotton balls.
Keep track of your symptoms, keep your hands clean, visit your doctor as needed, and follow your treatment instructions carefully. Within a week, your eyes should be feeling better.
To avoid spreading the germs that can cause eye infections:
One of the best things you can do for your baby blues (or greens, or browns, or hazels, or whatever color your eyes are) is to have them checked by your doctor whenever you have a physical examination. If you’re having trouble seeing or you’ve been getting frequent headaches at the end of the day, tell a parent so that you can have your eyes examined by an eye specialist.
An ophthalmologist (pronounced: ahf-thuh-mah-luh-jist) is a medical doctor who specializes in examining, diagnosing, and treating eyes and eye diseases. An optometrist (pronounced: ahp-tah-muh-trist) has been trained to diagnose and treat most of the same eye conditions as ophthalmologists, except for treatments involving surgery.
It’s a good idea to have your eyes checked at least every 2 years or even more frequently if you have a family history of eye problems such as glaucoma or early cataracts.
The best rule of thumb for when to see an eye specialist if you injure your eyes is “when in doubt, check it out!”
Your eyes do some great things for you, so take these steps to protect them:
The eyes you’ve got will be yours forever – treat them right and they’ll never be out of sight!
Have you ever wondered whether there’s any truth in some of the stuff you may have been told about how to treat your eyes? For example, you may have been warned that sitting too close to the TV or computer can ruin your eyes. But actually that’s wrong. You may also have heard that using a night-light (instead of bright light) to read will cause nearsightedness, but there’s no clear scientific evidence to support this idea. You can strain your eyes if you don’t have enough light when you read, but it won’t ruin your vision.
Just as you wear a seat belt to protect yourself when you’re in a car, it’s a good idea to protect your eyes before something happens to them.
Wearing sunglasses is high on the list of ways you can care for your vision. Buy a pair of sunglasses with ultraviolet (UV) protection to use whenever you’re in the sun. UV light causes long-term damage to the inner structures of the eye, but wearing sunglasses whenever you’re in the sun can help prevent conditions such as cataracts and macular degeneration. A cataract is an eye condition in which the lens of the eye becomes clouded, impairing vision. Macular (pronounced: mah-kyuh-lur) degeneration is an eye disease in which the macula, a structure within the eye that allows you to see, gradually deteriorates, leading to decreased vision or blindness. (Need one more reason not to smoke? Smoking puts you at greater risk for developing macular degeneration.)
You can also care for your eyes by putting on protective eyewear whenever you play sports like racquetball or when you’re doing projects in shop class or the science lab. It only takes a second for something to hit an unprotected eye and cause serious damage.
Lots of teens are injured while playing sports – but getting hurt doesn’t have to happen. A few sports injury prevention steps can help to keep everyone in the game. Read on to learn the basics of sports and exercise safety.
Did you know that playing tennis with a badly strung (too loose or too tight) racquet while wearing worn-out shoes can be just as dangerous as playing football without shoulder pads? Using the wrong – or improperly fitted – equipment is a major reason why teens get injured.
The equipment you wear while participating in sports and other activities is key to preventing injuries. Start with helmets: They are important for sports such as football, hockey, baseball, softball, biking, skateboarding, in-line skating, skiing, and snowboarding – to name just a few.
Many pediatric computer vision eye doctors believe that heavy computer use among children puts them at risk for early myopia. They point to several recent studies as evidence that computers can have a negative impact on a child’s vision:
Many pediatric eye doctors believe that environmental stress of the “indoor world” rather than heredity is creating the myopia (nearsightedness) epidemic. In fact, children using computers before their visual systems are fully developed are at the very heart of the public health problem called computer vision syndrome. To prevent your child from suffering from CVS, follow these five tips:
Yet something you might do every day – staring at a computer screen for a long time – can strain your eyes. That’s because most people blink about 10 times per minute. But when you stare, your blink rate can go down to two or three times per minute. The best thing you can do is to blink more! It also helps to change your focus frequently. Look at something across the room for a few moments and then go back to looking at the computer screen.
If your eyes feel dry and irritated when you use the computer, use artificial tears. Don’t use products that remove the red from your eyes, though, because they may contain a chemical that eliminates redness temporarily but actually makes your eyes look worse later.
You should take special care of your eyes if you have a medical condition such as diabetes or juvenile rheumatoid arthritis because these conditions put you at an increased risk of developing serious eye disease. Be sure to see your doctor at least once a year if you have any medical condition that can affect your eyes. Depending on your situation, your doctor may need to check your eyes as often as every 3 months.