Why Testing for 20/20 Vision is Not Enough
- Convergence & Convergence Insufficiency
- Some Common Vision Problems.
- Focusing on Hidden Vision Problems in Children
Featured Offsite Link: Through Young Eyes
- Acquired Brain Injury: How Vision Therapy can help.
- The Amazing Truth of 20/20 Eyesight.
- Beyond the Looking Glass: A detailed look at symptoms of vision problems.
- How to Identify and Refer Patients for Vision Therapy
- Ortho-K: How You Can Improve Your Vision Without Surgery
- Optometric Checklist for Educators, Parents, and Patients (Information + Print-Out Form)
Newest Articles:
Glossary of Common Vision Conditions
- Amblyopia, Strabismus:
- This occurs when one eye turns in or out, up or down, or there is a lazy eye. In this condition you may see double or print may run together.
- General Binocular Problems:
- When the two eyes fail to work together, eye strain and fatigue can occur. If left untreated, reduced comprehension or avoidance of reading are commonly found.
- Visual Perceptual Dysfunction:
- This occurs when eye-hand coordination, visual memory, reversals, and other visual perceptual areas are deficient or undeveloped. This results in decreased efficiency in the development of learning.
- Inappropriate Visual Development:
- When visual skills of infants are not developing appropriately, strabismus and other visual conditions may occur. If treated immediately, the prognosis is excellent.
- Closed Head Trauma Syndrome:
- As a result of a head injury, visual skills may be lost or deficient. Often double vision, disorientation and other visual problems result, which should be treated as soon as possible.
The Amazing Truth of 20/20 Eyesight.
I'm Dr. Barry Tannen, a practicing optometrist in Hamilton Square, NJ. And I have a message that I believe is of vital importance to you and your family.
I've performed over 20,000 eye examinations in nearly 20 years of practice and I discovered some very interesting things.
Firstly, what do you think of when I say normal vision? If you're like most people the first thing that comes to your mind is 20/20 eyesight. But what does 20/20 eyesight really mean?
In 1862, a man named Snellen devised a testing system to determine people's eyesight. He asked people to stand at 20 feet and through experimentation discovered the smallest sized letter that most people with good eyesight could see. He called this a size 20 letter and the vision was recorded as 20/20. At the time it was thought that this was all you needed in the way of vision. Actually it was a great breakthrough at the time. Now, over 130 years later, we have made quantum leaps in our knowledge of the human visual system. Yet, if you walk into many schools and pediatrician's offices and even some eye doctor's offices the old 20/20 standard is still the only way that vision is tested.
20/20 eyesight tells us how well we can see to drive or to see a blackboard. It tells us if we can see a newspaper or a computer screen. But there are many things 20/20 eyesight will never tell us. It will never tell us if you or your child:
- sees clearly all day long
- can focus back and forth to the blackboard and book
- sees single rather than double
- can read without getting a headache
- can follow words on a page without losing his place
- can read without wanting to fall asleep
- has healthy eyes
Do you think that these things would be important to a student or anyone for that matter? Of course they are!
Most people do have healthy eyes, but it is critical that we carefully evaluate the health of the eyes every time we do an eye exam. That is also one of the main reasons I strongly recommend yearly eye health examinations to my patients. But let's assume for a minute that your eyes are healthy and let's talk about your vision now, and the way it was 10,000 years ago.
Why would I even mention your vision 10,000 years ago?
It's important to understand how our visual system evolved in order to really understand the demands we place on our vision today. What did we need our vision for 10,000 years ago when we were cave people? The two main functions we needed our vision for were:
- to hunt for food in order to survive.
- to keep from being hunted so that we didn't become food for some other animal.
Both of these were decidedly distance vision needs. Therefore, our visual system evolved over many thousands of years to allow us to see clearly far away.
- About 500 years ago everything changed. That's about when the first printing press was invented.
- 150 years ago factories and crafts came into widespread use requiring near vision extensively.
- And it was only about 100 years ago that compulsory education was first introduced in this country. 100 years sounds like a long time, but it's not even a drop in a bucket with regards to the time it takes for something to change by evolution.
- Over the past 20 years, with the advent of personal and business computers, our world has been drawn increasingly to near vision tasks.
Near vision tasks make up the majority of our workday today. Yet our visual system was really designed by evolution to be more for distance viewing than near.
There is an inherent mismatch between our distance preference vs the constant, intense near-seeing work that your children and you do both at school and on the job. One fact that points to this is that the #1 complaint of computer users is eyestrain.
There is a lot of evidence that suggests that near vision tasks are inherently stressful to individuals. A group known as behavioral optometrists developed extensive examination techniques and treatment recommendations based on this fact. This is called the Nearpoint Visual Stress Theory.
Let me demonstrate to you in a concrete way what nearpoint visual stress is. Take the index finger of your right hand and hold it way out in front of you, at the same level as your nose. Focus on the tip of your finger and start bringing slowly towards your nose. Start bringing your finger in towards your nose until you feel some discomfort or stress in your eyes or your forehead, and keep your finger at this position.... Did you start to feel some discomfort at a certain point? If you did, like most people, that feeling is an example of nearpoint visual stress. When I lecture to a room full of people and ask them to do this, I notice that different people will stop their fingers at different distances from their nose. Some will get very close to their nose, others will stop at 1 or even 2 feet from their nose. This is one way a behavioral optometrist can determine how nearpoint visual stress is affecting you.
Imagine a typical child for example, who is spending hours each day exposed to schoolwork, computers, computer games...all at close distances. How can this child respond to this nearpoint visual stress?
One way is that they develop physical changes in their eye to handle difficult situations. You need to see near? Then give up distance for near. This is a child who:
- holds things very near
- squints when they look up from their books
- has difficulty copying from the blackboard
- and eventually they become myopic or nearsighted
Now of course there are genetic factors at work also. In other words, if your parents are nearsighted, you will have a greater tendency to become nearsighted. But the amount of nearwork you do is becoming more and more an issue as we research the cause of nearsightedness.
Another way nearpoint visual stress can affect a child is that they force themselves to do the work, but with reduced understanding or efficiency. This is the child who might...
- take an hour and a half to do 30 minutes of homework
- works below their academic potential
- skips and re-read lines and words
- falls asleep when reading
- sees double when reading
Often times this child is getting passing grades or occasionally even good grades, but they're working so much harder than they have to. They're just not performing up to their ability.
But perhaps the worst response of all to nearpoint visual stress is avoidance. This is the child who cannot tolerate near work and refuses to do it. This is a child who....
- has a short attention span
- misbehaves to avoid doing near vision work...he/she is the class clown, perhaps they are moody, aggressive, or even delinquent.
- This is the child who may become an auditory learner- he or she listens in order to learn. This sometime works in earlier grades but not in high school or college.
- Many times they are bright, intelligent children but again they are underachieving academically.
Do you know somebody who falls into one of these categories? Perhaps even your child?
The great news is that we can do something about this. By performing a thorough eye examination including a complete nearpoint vision analysis, a behavioral optometrist can discover whether you or your child has a condition caused by nearpoint visual stress. Many times we can make a significant difference by simply prescribing the appropriate nearpoint or relaxing eyeglasses. Sometimes these simple glasses alone can restore the efficiency of the visual system. I've had many parents tell me great success stories about how the appropriate nearpoint lenses had a tremendous impact on their child's reading comfort.
Other times we recommend vision therapy to restore visual abilities and improve a condition caused by the nearpoint visual stress syndrome. Vision therapy is a remarkable step by step program designed to restore the efficiency of the visual system. Using specially designed computers, lenses, prisms and 3D devices known as stereoscopes, we can many times help a child or adult improve their basic visual abilities.
What are the basic visual abilities?
The ability to sustain focus and shift focus back and forth is called accommodation. This visual ability can become impaired in children and adults. Imagine looking at a newspaper and having it go in and out of focus hundreds of times a day. Wouldn't that be uncomfortable. That's the way it can look for someone with an accommodative or focusing disorder.
The ability to keep the two eyes perfectly aligned on a book or other nearpoint work is called binocularity. This is a visual ability that often becomes impaired in children or adults. Do you know that even the slightest misalignment of the two eyes can cause double vision. Worse yet is that slightly double vision while reading may not be recognized as being double by a child. They may just say the print looks blurry or their eyes hurt, or worse yet they may say nothing at all, but just avoid reading all together.
The ability to follow sentences from word to word and line to line accurately, can become impaired or never develop properly in the first place. This is called an ocular motor dysfunction. Our office is one of the few offices in New Jersey that, has a computerized eye tracking instrument called a visagraph that carefully monitors a child's or adult's eyes while they're reading. By doing this, we can get a precise simulation of how they track the words on a printed page including how their performance compares to other people of the same age.
Relatively few of my patients actually need a vision therapy program. But for those that do the results sometimes are remarkable.
- I've had children who took 2 hours to do homework now taking 30 minutes.
- Children who hated school who now love it
- "C" students become "A" students
- Adults and children who got headaches every time they read, get rid of their headaches.
Again, vision therapy is not indicated for everyone. For example, we do not teach children to read in vision therapy. But if your child or someone you know has a nearpoint vision problem that is affecting their ability to learn, vision therapy can allow them to achieve their potential.
How do you know if a nearpoint visual problem is affecting you or your child? There is really only one way to know. You need to get examined by a behavioral optometrist or by an optometrist who performs a thorough nearpoint vision analysis. Remember, an eye exam that concentrates only on "are the eye's healthy, and do they see 20/20 is not enough."
How do you find a behavioral optometrist? One way is to call a national organization known as the College of Optometrists in Vision Development. They grant Fellowship status only to those optometrists who pass a rigorous oral and written test in behavioral optometry and vision therapy. Their telephone number is 1-888-268-3770. Ask them for a list of certified fellows in your area.
If you think that you, or your child may have a nearpoint vision problem that is affecting their school or work, we can perform a comprehensive eye exam which includes a thorough nearpoint vision analysis. Perhaps your's or your child's problem is as simple as needing the proper nearpoint glasses, or maybe you or your child needs a vision therapy evaluation. Or maybe there is no vision problem at all, but it would be great to have peace of mind. Whatever the case, you can be certain that we know that it takes more than 20/20 vision to learn and work properly.
Beyond the Looking Glass.
A significant number of children (20%-25%) in our classrooms are suffering from undiagnosed visual problems. These visual skill deficiencies can reflect in both performance deficits and behavioral adaptations. The more parents, teachers, and related professionals become aware of symptoms which typify these visual problems, the better we are able to identify those children who are at risk.
It is important to differentiate the measure of sight from the complex process of vision. Sight is the simple response of the eyes to light and to the differences in brightness contrasts. Vision is a sensory-motor-perceptual process. It is the ability to identify, interpret and understand what is seen. Vision is learned and constantly undergoes change and development. Many of these children with learning related visual problems have 20/20 distance eyesight but cannot sustain prolonged near visual work without visual stress or avoidance.
Following are definitions of the primary physiological skills required to perform efficiently along with a checklist of symptoms which typify deficiencies in these visual skills.
-
Eye Movement Skills (tracking) - the ability to move the eyes
smoothly, accurately and effortlessly in tandem whether following a line of print in a book or the flight of a ball through the air.
Symptoms:
- head turns as reads across page
- loses place often during reading
- needs finger or marker to keep place
- too frequently omits small words
- displays short attention span in reading or copying
- writes up or downhill on paper
- rereads or skips lines unknowingly
- Focusing Skills (accommodation) - the ability to look quickly
from far to near and vice versa without momentary blur (e.g.
looking from the chalkboard to the book). This skill involves the clearing of an image for identification.
Symptoms:
- tires easily
- blinks to make the chalkboard clear up after desk work
- rubs or blinks eyes during or after short periods of visual activity
- makes errors in copying from chalkboard to paper or desk, or from reference book to notebook
- avoids near centered visual tasks
- comprehension reduces as reading is continued
- loses interest too quickly
- Eye Teaming Skills (Binocularity) - the ability to use both eyes together smoothly, equally, simultaneously, and accurately. All judgements of spatial localization, depth perception and the accuracy of a single clear image depend upon this paired action of the eyes.
Symptoms:
- squints, closes or covers one eye
- extreme head tilt while working at desk
- complains of seeing double (diplopia)
- omits letters, numbers or phrases
- repeats letters within words
- misaligns digits in number columns
- Eye-Hand Coordination Skills (visual motor integration) - This ability
is dependent upon the use, practice and integration of the eyes
and the hands as paired learning tools. With this skill comes more
effective ability to make visual discrimination of size, shape, texture and location of objects.
Symptoms:
- writes crookedly, poorly spaced; cannot stay on ruled lines
- uses finger or hand to keep place on the page
- must feel things to assist in any interpretation required
- uses other hand as a "spacer" to control spacing or alignment on the page
- eyes not used to "steer" head movements
- extreme lack of orientation in placement of words or drawing on the page
- concepts of laterality and directionality (right-left awareness),
- visual memory and visualization,
- Visual closure,
- figure ground discrimination.
Adaptations to visual problems vary widely. Some symptoms of visual stress can be difficult to observe. Some individuals avoid sustained visual activities. Others, who are highly motivated, may work unnecessarily hard to compensate for the burden of visual inefficiency. The child will not outgrow these visual problems, but rather must adapt. Behavioral avoidance responses often develop to mask expected failure, self esteem is reduced and true performance potential is distorted.
Visual examinations which only evaluate sight and health are not adequate enough to rule out these types of visual skill deficiencies. Therefore, it is essential that visual skills are evaluated at the near working distances. If visual skill deficiencies are diagnosed, a remediation program (vision therapy) is essential to alleviate these skill deficits and the related visual stress symptomatology. A vision report should be sent to the school and related professionals to support a team oriented approach to the student's performance and/or behavioral difficulties.
The American Optometric Association has stated that, based on extensive research, vision therapy is effective in the treatment of physiological, neuromuscular and perceptual dysfunctions of the vision system.
Please note that
- in no way is this treatment involved in teaching reading, but rather in improving the visual skills required to perform at this task efficiently;
- early diagnosis and treatment is essential if secondary behavioral adaptations and/or related educational lags are to be avoided;
- being bright does not mean you can't have a visual problem, it only means you must apply more effort to compensate for these inefficiencies;
- our best combatant against the large numbers of undiagnosed children with visual skill difficulties is good observation by parents, teachers and related professionals, and annual vision examinations which go beyond the "looking glass".
URL=http://www.visionhelp.com