Wednesday, October 29, 2008

A good vision is not only seeing 20/20

Enlace a entrada en español

Just as “seeing” is not the same as “looking”, talking about vision it is not only enough that light focuses in a specific point of the retina in order to see 20/20, but also, vision is understanding what we see.

In order to understand this concept, I will firstly explain what the words Visual Acuity mean, that many times we utilize them with our patients when we say “You have 20/20 vision“, but maybe you are not quite sure what actually that means.

When we assess the Visual Acuity test, we are assessing the ability that someone has to identify some letters or patterns from a distance where they should be seen; and the final value is the smallest symbol size than the patient is able to read from that distance.

Let me explain it better: when we perform this test, the patient must sit down 20 feet (6 meters) away from the letters chart. When we say that a person have 20/20 visual acuity (100%, 1.0 or 6/6, everything is the same), what we mean is that the person sees 20 feet away from the chart what she should actually see 20 feet away. But for instance, if that person has 20/10 visual acuity (6/3 or 0.5), that means she would only see from 20 feet what she should see from 10 feet, that is, she has 50% of vision.



Therefore, Visual Acuity is the ability to see the details of an object. But precisely because that object is not floating in the void, but furthermore, there are many more objects surrounding it, we are in a distance from that object, we may want to execute an action with it and other senses may be implicated in this action…, vision is just not only clearly seeing that object, but that many more “visual qualities” might be implicated, as we saw in a previous post .


“It is estimated that as much as 80 percent of all learning during a child’s first 12 years comes through vision”.

Because a child or an adult has 20/20 visual acuity according to a certain test, it does not mean she has good vision, since she may have problems in order to focus on a text when she reads a book, or may have bad eye-hand coordination and consequently have a bad writing, or may have some problems to how her eyes work as a team and they feel tired 10 minutes after they start a near task, or may be "clumsy" and hit herself with things because she does not calculate the distances well. In all of these examples, vision is involved and with them I only wanted to show that although we have a 20/20 Visual Acuity maybe we do not have a 100% Vision.

In many optician’s, when a person goes to check her vision, they only obtain this result and only find out the lens required to improve that percentage (whether there is myopia, hypermetropia or astigmatism), without assessing if that vision works well and if it works along with the other senses. That is, for them the goal is to obtain 20/20 visual acuity and they do not think in any other symptom that shows that it is not only important to improve Visual Acuity, but also to improve the performance working at near, or practicing a sport or reading and its comprehension. For it, as the daily problems are not always related to a visual problem, I recommend you to go to a specialized office that offers you a broader eye examination. You would be surprised of how many symptoms and problems at school can be removed by using Visual Therapy, and what this can be done to improve the quality of life in general of any person.

A child may be diagnosed with a “perfect vision” by an optician or an ophthalmologist (it doesn’t matter) simply because she has 20/20 visual acuity, but without being assessed the necessary visual skills (focusing, peripheral vision, eye-hand coordination, discrimination of shapes, spatial relations,…) required to have a correct learning or a good physical coordination. In a later post I will thoroughly explain the visual problems related with learning.


If a child is struggling with academics, sports or home behavior, parents and teachers should be encouraged to consider that a vision problem may exist, beyond a Visual Acuity.


A simple comparative example is the following one: when we read, it is not enough to verbalize what we see written and to read as a parrot, we have to understand what we see. Therefore, when we read, we must not only clearly see the letters, but we have to know, to remember, to interpret and verbalize what is written; vision process is responsible for all this.


So, after all this, mi goal is for you to have a clear understanding that when you go to an office or optician’s, the Visual Acuity assessment must be ONLY a value obtained of the whole visual examination in order to achieve a precise diagnosis.



BOOK: "20/20 is not enough"

Monday, October 06, 2008

An apple a day really does keep the doctor away

Enlace a entrada en español



This idiom is very famous, but we do not always heed this advice.


Prevention and Early Detection

Optometry basically detects visual upsets, that is, visual problems, performance problems related to vision, development problems related to vision, and so on. Therefore, if this detection is made as soon as possible, the treatment will be more effective, will need to carry out it less time and the results will be more lasting.


How can you know if you suffer any visual upset?

FROM THE FACT THAT THERE IS NO OCULAR PATHOLOGY OR ILLNESS, if you notice that you have some troubles in order to see at distance or at near (in order to read, write, draw, watch TV, drive, practice any sport, use a computer,…), this indicates that probably, you are suffering from some “refractive error” (myopia, hypermetropia, astigmatism, anisometropia, presbyopia... concepts that I will explain in later posts). These visual problems are not pathologies or eye illness, but they may cause a big discomfort performing the tasks of daily life, although they have an insignificant value.
These problems are “quantitative visual disorders”, and using a prescription (eyeglasses, contact lenses or prisms), usually they are corrected (THOUGH NOT REMOVED).

But, in the other hand, there are other “problems of quality vision” (they are not eye illness neither), that we can not be shown to the patient with understandable quantitative data, but that, however, may almost cause more frustration and powerlessness than the previous problems. This is because many people do not know very well what happened, or where they can go with their problem.
Fortunately, there are more and more optician’s shops or offices where they perform visual exams are more complete than a simple ocular refraction in order to obtain those “refractive errors”. There they detect the reason of it: a performance problem at work or at school, a learning disability, a visual development problem, a clumsiness or balance problem, an inability in order to read a book during long time, a carsick, a dyslexia, and so on. I guess that you did not imagine the great relation that there is between vision and all things that we do daily; and many times you do not realize that, by treating a problem from vision, we can solve the visual problem and the trouble that you did not know how “solve”.


What can you do if you have a visual problem?

If you have any of these problems or any other that you think that can be related to vision (if you have some question, you can consult me about it in the comments, in order to confirm if your problem is or not a visual problem that any of my colleagues may diagnose; I am sure that many people have your problem too, and if I advise you, we can help more people; but how I wrote in the welcome post, I will never give you a solution or treatment for your problem, because I would need to assess each case in an isolated way), I recommend you to visit a qualify optometrist and you ask him a comprehensive visual exam. Afterwards, he will give you the better treatment option (refractive prescription, vision therapy, reflexes therapy or rhythmic movement therapy, syntonic phototherapy... – treatments that as well I will explain at length in later posts-), or will refer you to the professional best fitted to treat your problem.


A small problem is always easier to treat than a big problem.