Monday 30 December 2013

Low vision Students in Class Room -- Considerations

For educational purposes, the low vision student is typically one who reads print and has a corrected visual acuity of 20/70 or worse in the better eye. Most low vision students have very poor distance vision, so this makes it difficult for them to see the chalkboard or to gather detailed information from filmstrips, charts, or overhead screens. These students can usually read print and gain information from pictures, charts, and graphs when the material is up close. Each low vision student's needs are unique, but the following suggestions may be helpful when working with a low vision student in the classroom.

Some General Facts Regarding Students with Low Vision:

  • Using the eyes does not injure or harm them. Encourage the student to use his/her eyes since greater efficiency can only be developed through the use of the eyes for visual tasks unless a doctor has indicated otherwise.
  • The use of glasses cannot help improve visual acuity for all eye conditions. Glasses may be worn to reduce glare and help with fatigue.
  • Some students can read ordinary type with ease; others may require large print, a hand-held magnifier, or a closed circuit TV.
  • The visually impaired child should be able to participate in most recreational activities except for those that require good visual acuity. (i.e. dodgeball)
  • Eyes cannot be "strained" but may tire quickly. An activity that allows the student to change focus is often helpful and appreciated.
  • Holding materials close to the eyes will not harm them. Allow the student to position materials at a distance he/she chooses.
  • Check the student's folder for the modification sheet. This will tell the classroom teacher what specific modifications need to be made in the classroom. Remember, these modifications are REQUIRED, since they are written in the student's Individualized Education Plan (IEP). Contact the teacher of the visually impaired if you have questions or need suggestions for your particular room.

Suggestions for the Classroom Teacher:

  • Preferential seating is often necessary for a student with low vision.
  • Let the student select a seat where he/she sees best
  • Seat a student as close to the board as practical
  • Reduce glare from windows and lights, as much as possible
  • Seat the student with his/her back to windows
  • Read the student's Functional Vision Evaluation to find out if this student can copy materials written on the board or overhead projector.
  • Purple dittos or "fuzzy" Xerox copies should not be used with this student. Clear contrast between the print and the background will help the student be more successful.
  • Black print on white paper is usually best. If other modifications are required they should be contained in the list of modifications handed out at the beginning of the semester and in his/her Functional Vision Evaluation of the Special Education Folder
  • Contrast, print style, and spacing of letters can be more important than print size.
  • Low vision students may require more time to complete assignment.
  • Low vision students are usually slow readers because of the visual impairment.
  • Standardized tests that require separate answer sheets may be especially difficult for a student to use. Check modifications to see what procedure to use.
  • Word games, puzzles and graphs may be inappropriate for a low vision student. Check with the VI teacher if you are unsure.
  • Give the student the grade he/she earns. Donating a grade to a student really hinders-not helps the student's learning.
  • Storing and using large print materials may be difficult for the student to manage in a classroom. Help the student find a place for books and supplies. Also, a locker may not be accessible if it has a combination lock.

Understanding A Low Vision Student:

  • The emotional needs of a low vision student are like those of any other. He/She wants to be liked by teachers and peers. They do not want to be different!
  • Schedule a time for a private meeting with the child. This will allow the student to tell you about seating preferences, lighting, and modifications that are helpful.
  • Have the student explain his/her visual problem to you.
  • Try not to call attention to the child's eye problem in front of the class.
  • Always use the student's name when addressing him/her.
  • The rules of discipline should be the same for a low vision student, as for any other, unless the IEP states otherwise.
  • So much of communication is non-verbal. Often a student with low vision is unable to recognize the expression on someone's face or figure out what has happened in a situation that is nonverbal. It is helpful if the teacher privately explains the situation to the student with low vision
  • Be aware of the student's frustration level since so much of learning and school is visual. It is easy for a student with poor acuity to become frustrated.
          If you notice the student has food or ink on his face or clothes, discretely tell    them.

What Eye Problems Look Like

Warning Signs of Eye Trouble

Blurry vision, spots, glare at night -- these are common eye complaints that can be harmless annoyances or an early sign of disease. In the slides ahead, we explore several eye problems and offer two quick eye tests. You'll see the world through eyes that have floaters, cataracts, myopia, and glaucoma. Be sure to see an eye doctor promptly for any concerns.

Nearsightedness (Myopia)

About 33% of Americans (ages 12-54) have a blurry view of distant objects, called myopia, up from about 25% in the early 1970s. Risk factors include:

  • Family history (one or both parents)
  • Lots of prolonged, close-up reading
  • Trouble with driving, sports, or seeing a blackboard or the TV may ensue. Symptoms   include blurred vision, squinting, and fatigue. Myopia can be treated with glasses, contacts, or surgery in some cases. 

   
   Farsightedness (Hyperopia)

Most of us are born with mild farsightedness, but normal growth in childhood often corrects the problem. When it persists, you may see distant objects well, but books, knitting, and other close objects are a blur. Hyperopia runs in families. Symptoms include trouble with reading, blurry vision at night, eyestrain, and headaches. It can be treated with glasses, contacts, or surgery in some cases.



Presbyopia

Just like gray hair or wrinkles, trouble reading fine print  is a sign of aging. Called presbyopia -- or "old eye" in Greek -- symptoms appear in the 40s. The eyes' lenses become less flexible and can't change shape to focus on objects at reading distance. The solution: reading glasses or bifocals, which correct both near and distance vision. If you wear contacts, ask your eye doctor about contacts made for people with presbyopia.



Nearsightedness: What Happens

Typically, an eyeball that's too long causes myopia. But an abnormally shaped cornea or lens can also be to blame. Light rays focus just in front of the retina, instead of directly on it. This sensitive membrane lines the back of the eye (seen in yellow) and sends signals to the brain through the optic nerve. Nearsightedness often develops in school-age children and teens, which need to change glasses or contacts frequently as they grow. It usually stabilizes by the early 20s.


Farsightedness: What Happens

In hyperopia, the cause is often an eyeball that is too short. Light rays focus behind the retina, causing close objects to be blurry. In severe cases of hyperopia, especially after the age of 40, distance vision can be blurred as well. An abnormal shape in the cornea or lens can also lead to farsightedness. Children with significant hyperopia are more likely to have crossed eyes (strabismus) or lazy eye (amblyopia) and may have difficulty reading. That’s one of the reasons eye doctors recommend vision exams for young children.



Astigmatism

Your vision may be out of focus at any distance with an astigmatism in one or both eyes. It occurs when the cornea, the clear “window” that covers the front of the eye, is misshapen. Light rays can be scattered in different points on the retina, rather than focusing on a single point. Glasses or contact lenses correct the problem, and surgery may be another option. Along with blurred vision, symptoms may include headaches, fatigue, and eye strain.



Color Blindness Test

Which number do you see in the far left? If it's "3," you probably have normal color vision. If it's a "5," you may be  colorblind. This view is simulated in the center panel and represents a mild color vision deficiency. About 10% of men are born colorblind, but few women. Complete color blindness (very rare) is simulated at right. No number is visible. Tinted glasses may help the colorblind see better.





Refractive Eye Surgery

Do you dream of seeing clearly without glasses? Surgery to reshape the cornea can correct nearsightedness, farsightedness, or astigmatism with a success rate of better than 90%. People with severe dry eye, thin or abnormally shaped corneas, or severe vision problems may not be good candidates. Possible side effects include glare or sensitivity to light.





Glaucoma: View

You can't feel it, but deterioration of the optic nerve oftentimes with elevated eye pressure can silently steal your sight, a condition called glaucoma.  There may be no symptoms until central vision is lost (following gradual loss of peripheral vision), so regular eye exams are critical to find it early. Those at higher risk include:

  • African-Americans over 40
  • Anyone over 60, especially Mexican-Americans
  • People with a family history

        

Fortunately, glaucoma can be treated with medications or surgery. Regular eye exams every 1-2 years, especially after age 40, can catch it early.

Glaucoma: What Happens

In the most common form of glaucoma, increased eye pressure leads to optic nerve damage and loss of vision. The eye is filled with circulating fluid that nourishes its internal structures. Sometimes the balance between fluid creation and exit is abnormal. The buildup of fluid increases pressure and damages the optic nerve at the back -- the bundle of 1 million nerve fibers that carry information to the brain. Without treatment, glaucoma can cause total blindness.

  

The bright yellow circle shows an optic nerve head that is damaged by glaucoma. The dark central area is the macula, responsible for finely-detailed central vision.

Macular Degeneration: View

Age-related macular degeneration (AMD) damages, then destroys, the eye's finely-detailed central vision, making it difficult to read or drive. Symptoms can include a central blurry spot or straight lines that appear wavy. Finding and treating AMD promptly can help slow vision loss. Being over 60, smoking, high blood pressure, obesity, and a family history of AMD increase your risk.




Macular Degeneration: What Happens

In AMD, the central part of the retina, called the macula, deteriorates. In the dry form, doctors often see yellow deposits called drusen in the macula. As dry AMD progresses, the macular tissue deteriorates, gradually shutting down the delivery of images to the brain.
In the wet form, abnormal blood vessels grow. They leak blood and fluid (seen here), causing scarring and further damage to the macula. Both types lead to a central blind spot.





Macular Degeneration: Test

Cover one eye and stare at the center dot in this Amsler Grid, from a distance of 12 to 15 inches. (You can wear your reading glasses.) Do you see wavy, broken, or blurry lines? Are any areas distorted or missing? Repeat the procedure for your other eye. While no self-test can substitute for an eye exam, this grid is used to help detect early symptoms of AMD.

Macular Degeneration:Signs

As seen here, the Amsler Grid can look quite distorted to someone with significant macular degeneration and may include a central dark spot. Straight lines that appear wavy are also cause for concern, as they can be an early symptom of "wet" AMD, the more serious and fast-moving type of macular degeneration. Your eye care professional will want to evaluate you right away, starting with a thorough dilated eye exam.

Diabetic Retinopathy: View

Type 1 and type 2 diabetes can cause partial vision loss (seen here) and lead to blindness. The damage involves tiny blood vessels in the retina and can often be treated, but don't wait for symptoms. By the time they occur -- blurry vision, spots, shadows, or pain -- the disease may be severe. People with known diabetes need annual eye exams, sometimes even more often if diabetic eye changes have begun. The best prevention is keeping your blood sugar in check.



Diabetic Retinopathy: What Happens

When high blood sugar levels go unchecked, it can damage the tiny blood vessels that support the retina. These blood vessels can swell, break, and leak fluid.  In some cases, dozens of new, abnormal blood vessels grow, a condition called proliferative retinopathy. The abnormal vessels are very fragile and break open easily. These processes gradually damage the retina, causing blurred vision, blind spots, or blindness.


 

Cataracts:  View

Age is not kind to our eyes. By the time we're 80 years old, more than half of us will have had a cataract, or clouding of the lens. Vision gradually gets foggy and makes it hard to read, drive, and see at night.  Diabetes, smoking, or prolonged sunlight exposure may increase the risk. Surgery that replaces the clouded lens with an artificial lens is highly effective.



Cataracts: What Happens

In good health, the lens focuses light into a sharp, clear image on the retina, which captures the image like film in a camera. As we age, protein builds up in the lens, clouding it, and sending scattered rays of light to the retina, instead of one sharp clear image. The result can be blurred vision, changes in color vision, and glare, especially at night. Very advanced cataracts are visible to the naked eye -- the muddy-colored circle at the center of this picture.



Retinitis Pigmentosa

RP is an inherited disorder that often begins with night vision problems, followed by a gradual loss of side vision, developing into tunnel vision, and finally, in some cases, blindness. One in 4,000 American have RP. A promising study showed that high-dose vitamin A supplements can reduce vision loss. However, you should consult a health care expert before taking supplements because too much vitamin A can be toxic.




Retinitis Pigmentosa : What Happens

The light-sensitive tissue of the retina slowly deteriorates over many years in people with RP. As this tissue dies, it stops sending signals to the brain, and some vision is lost.  Eye exams show abnormal dark spots (pigments) sprinkled around the retina. Early cataracts can also occur, as well as a swelling of the retina called macular edema (the central orange mass seen here).




Floaters and Specks

Blurry spots or specks in your vision that move may be floaters -- debris in the eye's vitreous gel. They don't block vision and are more easily seen in bright light. Floaters are common and usually harmless. But if they appear or increase suddenly, or are accompanied by light flashes, you should see a doctor. Vision abnormalities that tend to be more serious include persistent white or black spots and a sudden shadow or loss of peripheral vision. These require immediate evaluation.





Amblyopia (Lazy Eye)


During childhood, when vision is reduced in one eye, the brain sometimes favors the other eye. This condition, called amblyopia, may stem from a misalignment of the eyes (strabismus or crossed eyes) or poorer vision in one eye. A patch or drops that blur the vision in the "good" eye can prod the brain to use the other eye. If untreated during childhood, vision loss from amblyopia can be permanent.





Eye Care: Tears and Dry Eye

Tears are the lubrication for our eyes. When not enough flow, perhaps due to dry air, aging, or other health conditions, the eyes can become painful and irritated. For people with mild cases of dry eye, occasionally using eye drops labeled artificial tears may do the trick. Others with more pronounced and frequent dry eye symptoms may need other medications or a procedure to block the exit ducts.




Eye Care: Pinkeye

Pinkeye, or conjunctivitis, is an inflammation caused by a virus, bacteria, irritant, or allergy. Along with the telltale redness, you might have an itching or burning sensation and a discharge. If itching is the main symptom, the cause is likely to be allergy. Most cases of infectious pinkeye are viral, which don't require antibiotics. Bacterial conjunctivitis is typically treated with antibiotic eye drops. Bacterial and viral conjunctivitis are very contagious, so wash your hands frequently while you wait for it to clear up.


Eye Care: Stye

A stye is a tender red bump that looks like a pimple on or near the edge of the eyelid. It is just one type of infection of the eyelids (blepharitis). Styes usually heal in a week, but using a very warm, wet compress three to six times a day can speed the healing. Don’t wear contact lenses or eye makeup until it heals.



Eye Care: Regular Exams

Everyone needs regular eye exams, starting before the school years. This is particularly important if you have risk factors or a family history of eye problems. Beyond vision issues, the eyes can reveal underlying health problems, such as diabetes and high blood pressure, or serious disorders like stroke or brain tumor. Bulging eyes are a sign of thyroid disease, and a yellow tint of the whites of the eyes may indicate liver problems.

Eye Protection: Sun

UV rays can damage your eyes, just as they do your skin. Regular overexposure to sun can cause cataracts 8-10 years early, and a single lengthy exposure can actually burn your corneas. The solution is sunglasses that block UV rays and a hat. People with light-colored eyes are likely to have a greater sensitivity to light. New or pronounced sensitivity to bright light can be a sign of a more serious eye condition.

Eye Protection: Everyday Hazards

Grease splatters from a pan, yard debris flies up from the lawn mower, cleaning solution splashes in a bucket. Some of the greatest hazards to the eyes are in the home. Eye care specialists recommend that every household have ANSI-approved protective eyewear. Even if an eye injury seems minor, go to the emergency room immediately to check it out.

Foods for Eye Health

     Carrots really are good for your eyes. So are spinach, nuts, oranges, beef, fish, whole                  grains, and many other foods in a healthy diet. Look for foods with antioxidants such as              omega-3 fatty acids; vitamins C, E, and beta-carotene; as well as zinc, lutein, and                        zeaxanthin. Research suggests those nutrients may reduce the risk of age-related macular        degeneration.

Saturday 28 December 2013

Optometrists : Eye Wear Guide

Screen Fatigue: Computer Lenses

Screen time can be a key factor in choosing eyewear today, with 70% of daily computer users reporting eye strain. Computer glasses may ease the blur.


Manufacturers say they help your eyes adapt to electronic words and images, typically viewed farther away than a book. Look for anti-reflective coating and consider a tint to reduce glare from harsh overhead lighting.



Presbyopia : Readers

Fine print seems to shrink as we age. What really happens is presbyopia -- the eye loses its ability to change focus. Reading glasses can help bring blurry print into sharp focus. You can buy "readers" at many stores. But if you need different strengths for each eye, require bifocals, or have an oddly-shaped eye -- called astigmatism -- see an eye care professional.



Nearsightedness: On the Rise

If it seems like more people wear glasses at younger ages, you're right. Myopia, blurry distance vision, has been on the rise since the '70s. Farsightedness, or hyperopia, is less common. Both require corrective lenses.  It's a myth that getting glasses will make your eyes weak. People may need stronger vision correction as they age. But that happens whether or not you wear glasses.

Coke-Bottle Lenses: New Technology

Do you avoid a new prescription for fear of thick glasses and a "bug-eye" look?  Ask your eye care provider about high-index lenses, which are thinner and lighter than traditional lenses.  You also may consider aspheric lenses, which are thinned out on the sides. Lenses can be both aspheric and high index. Both can help you avoid a thick, unflattering shape.



Bifocals and Beyond
 
 

Do you need different glasses to watch TV and to read? You're a candidate for multifocal lenses. Bifocals have an area at the bottom for reading. The rest is for distance. Trifocals add a middle zone for vision 18 to 24 inches away, handy for computers. Progressive lenses, or "no-line bifocals," offer a gradual shift in strength -- invisible to your younger co-workers.

Risky Games: Polycarbonate Lenses

A racquetball travels between 100 and 150 mph. Imagine the force of that ball hitting you in the eye! Your best protection is sports frames with polycarbonate plastic lenses. They're 10 times stronger than other materials.

Sports with the most eye injuries include all racket sports, baseball/softball, ice hockey, basketball, and lacrosse. Protective eyewear could prevent 90% of sports-related eye injuries.

Advantage: Yellow Lenses

If you're wearing sunglasses for sports, consider colored lenses that may enhance vision for your particular sport. Yellow lenses may help in low light or haze to provide a sharper image.

They're popular with skiers and snowboarders, cyclists, and indoor athletes like basketball players and racquetball players.

Advantage: Green Lenses

Green lenses may heighten contrast while still keeping the balance of colors. They're popular for golf and baseball. Golfers say the green lenses make the ball stand out on the green (simulated in our picture). It's not yet clear that one lens color has the edge over another, so try before you buy. Many stores have samples to try with simulated light to see what color might work for you.


When Do You Need an Eye Test?

Getting the newest lens technology starts with an eye test. You should have an exam at least every two years -- to be sure your glasses are the right prescription and to look for medical issues. An exam can find cataracts and glaucoma, as well as illnesses like diabetes, heart disease, aneurysms, HIV, and cancer. Signs of disease may be visible in, on, or around the eyes long before symptoms appear.

Warning Signs of Eye Trouble

Call your Optometrist right away for any of the following symptoms:
  • Sudden appearance of floaters in your vision
  • Partial loss of vision
  • Sudden eye pain or redness
  • Scratchy, irritated feeling
  • Blurriness or cloudiness


Match Eye-wear to Your Life

Start with practical considerations when choosing eyewear. If you tend to crush things in your purse, remember that metal frames bend (and can be repaired), but plastics break.

You should never leave glasses in a hot car, but could it happen to you? Plastic frames warp and can't be fixed. Metal frames just get really hot. If you don't like glasses or need peripheral vision for sports, contacts are a great alternative.

Framed: Flatter Your Face


When picking glasses, have your prescription in hand and consider these guidelines:
  • Smaller frames hide a strong  prescription.
  • Contrast flatters the face shape. For example, squarish frames on a round face.
  • Strong, dark frames draw attention away from features you don't like (a chubby chin).
  • Cat's-eye frames that point up at the corners can give the appearance of a mini facelift.
  • Color can blend with your hair and eyes, or contrast for a bigger statement.

       

Framed: For Business

If you work in a traditional field, think about titanium, stainless steel, or rimless frames for a professional look. For men, consider frames in brown, black, silver, or gunmetal. They're conservative colors and easy to match with professional clothes. For women, consider black, brown, silver, burgundy, and golden tones for the same reason. Tortoise-shell tones also are a classic.



Framed: Get Creative

Show off your creative fashion sense with interesting metal or plastic frames in unusual colors and unique designs.

      

Look for geometric shapes, contemporary larger frames, multi-color laminates, prints (animal and flower), or lasered details. Retro and vintage styling -- ranging from cat's-eyes to aviators to mod fashions -- also are back in style.

Framed: Gems, Wood, Horn, and More

If you want your personality to shine, look for trendy frame materials. You can find frames in wood, bone, and even buffalo horn. Show flair with gold (yes, real gold) frames or frames decked out in crystals or semi-precious or precious stones. Some frames are leather or wrapped in velvet. You may even find frames adorned in feathers, for an airy statement of your personal style.



Sunglasses: A Cloudy Day Must

Harmful ultraviolet (UV) rays can pass through clouds, so sunglasses are a must -- sunny and cloudy day alike. Sand, snow, water, and your car's windshield all reflect extra light and call for eye protection. Look for sunglasses with 99% or 100% UVA and UVB blocking. As an added benefit, sunglasses help protect the tender skin around your eyes and may help prevent cataracts.

Polarized Lenses: Good Bye Glare

Sunglasses with polarized lenses are popular with people who spend time on the water or in the snow because they cut glare from reflected surfaces. And they've been adopted by many others who like a glare-free view. Anti-reflective coatings fight glare, too. Mirror-coated lenses have a purpose beyond their style: They limit light coming into the eye, great for very bright conditions.


Blue Blockers: Clarity and Sleep

Blue blockers usually have amber-colored lenses. They block blue light, which has been linked to eye damage. Because they also heighten contrast, they're popular with hunters, pilots, boaters, and skiers. Blue light also suppresses melatonin, the sleep hormone. At least one study showed that people who wore blue blockers in the morning slept better at night.

Something Shady: Photochromic Lenses

When you need glasses but don't want to also buy prescription sunglasses, photochromic lenses are an option.

They're clear indoors and darken automatically in bright sunlight. They block 100% of harmful UV rays and are handy for kids, who play outdoors a lot. One downside: They don't darken in a car; most windshields filter out the UV rays that trigger the color change.

How Does the Sun Damage Your Eyes?

As we age, the odds of developing cataracts -- cloudiness of the eye's lens -- increase. Wearing sunglasses may delay cataracts. Sunglasses also may protect against macular degeneration (a disease of aging that harms central vision) and growths on the eye, both benign and cancerous. After cataract surgery, polarized glasses -- even indoors -- may reduce discomfort from glare.

Don't Skimp on Kids' Sun Protection

Children need sunglasses just as much as adults do, maybe more -- because they're outside more often than adults are and their eyes are more sensitive. Make sure kids' sunglasses offer the same UV protection that you'd look for in an adult pair. Although 2/3 of adults buy sunglasses for their children, only 13% check to make sure they protect against UV rays.



Screen Time and Children's Vision

Do your kids have their noses glued to the computer or video game system? Get them outside. Some studies show that children who spend a lot of time on the computer or doing other up-close work, even reading, have a higher rate of myopia than other kids. And kids who spend a lot of time outside have lower rates of myopia.

Pediatricians recommend no more than two hours a day of screen time for kids.

Protecting Eyes on the Job

Research shows 2,000 people each year have eye-related injuries on the job. About 90% of them might been prevented by wearing eye protection.
Eye injuries are caused by chemicals, foreign objects in the eye, steam burns, radiation exposure, and contagious diseases. Nonprescription safety eyewear offers good protection.  It must have nonremovable lenses and be permanently marked with "Z87."

Underwater Vision: Goggles

When swimming, snorkeling, or scuba diving with beautiful undersea creatures, using prescription glasses or contact lenses can be tricky. One option: goggles or scuba masks custom-made for your vision. You may need a slightly different prescription for  underwater use, because goggles can sit a little closer to your eyes than regular lenses, and a mask sits further away.