Thursday, March 26, 2009

Regarding a movie: “Blindness”

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A digression on the “Myopia series”.

Some days ago, I went to watch a just premiered movie “Blindness”. I will leave my personal criticism out since this blog is not about movies or books. But as a plot, for those people that have not read the book of the same name by Jose Saramago (from which the movie is adapted), or have not watched the movie, I will tell you briefly that it is about how panic and paranoia invaded a whole city when, one by one, all citizens are victims of a sudden blindness called “white illness”. The human behavior and condition give an exorbitant turn.

This novel/movie shows clearly how men are used to vision and how they give it very little importance when they own it. People that are born with vision, they do not know what they own. Fortunately only 3% of the world´s blind population are children. All of our daily activities require a good vision, from the time we wake up in the morning and we look at the watch, until we go to sleep and prepare the alarm clock for the next day. “Time concept” is very important for a blind man, that without light, has to learn to distinguish in what moment of the day he is, surrounded by that constant darkness –clarity-; in the case of sudden blindness, this causes a disturbance in the human biorhythms, and he does not know when he has to eat or to sleep.
A team of neuroscientists of the Visual Neuroscience Training Program at Johns Hopkins Institute, Baltimore (USA) has discovered (December 2008) a small number of light sensors (nerve cells) in the retina of our eyes, that communicate with the brain through very tiny and slow signals; and, unlike cones and rods, these cells contain MELANOSIN, which are not used for seeing images, but to monitor light levels in order to adjust the body’s clock and control constriction of the pupils in the eye (among other functions).

Ask yourself, what activities, simple or complex, you perform throughout the day WITHOUT THE NEED TO USE VISION… NOTHING, even when we dream, we see images. Many jobs such as computer users (a very high number of people, even those that work at home, and it is increasing), surgeons, taxi drivers, bricklayers, architects, dentists, plumbers, etc., need to have vision 100% of their time, or rather, we are used to use our vision 100% of our time.

At school, the reading and writing learning process of the children requires that 100% of the information that arrives to the brain gets in through the eyes. The school learning is purely visual. Really MEN ARE MAINLY VISUAL; human evolution has created us this way, it has created us such dependence on vision that when something like this happens and the adaptation of environment does not cause the immediate development of other senses, the first reaction of our brain is to change our behavior. In the case of the novel /movie, the change is not positive, but like in war moments, catastrophes, etc., it is proved that the human condition does not always offer its best face.

There are many people that do not like the changes in their life, regardless of whether these changes are controlled as uncontrolled (book: “Who moved my cheese”); but when you lose something that the rest of your life depends on, such as vision, this involves a change in your thinking, your habits, your hobbies, your plans and definitely your whole life.

One defect of our human condition is that WE DO NOT APPRECIATE WHAT WE HAVE.


This post is only an approach that I wanted to show you, in order to appreciate your vision and take care of it. Asking yourself: “What if I’d done this or that…”, always happens, but it can be late!!!!

Tuesday, March 17, 2009

Refractive disorders: Myopia (3). Solutions

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Myopia is not an illness, that’s why it can not be “cured”.
  • If you want to “compensate” a myopia or its problem of blurred distance vision, the treatments most commonly used imply wearing eyeglasses or soft contact lenses (mainly disposable ones); in order to go to the theater, to drive, to walk, to watch TV, to practice some sport,… In this case, myopia is corrected with minus or diverging spherical lenses (thicker at the edges than in the middle of the lens), that optically falls behind the image on the retina.
  • But if you would like to “try to stop” that progression as much as possible, the perfect thing would be wearing contact lenses and still better, if they are semi-rigid permeable ones.
    Besides this, the ideal thing would be to perform a series of simple visual exercises, which mainly teach us how we should correctly use our ability of focusing (accommodation) and how we could teach our visual system to be less “focal”, so that, although we are performing much near work with papers, computer, books, notes, homework, and for many hours, we do not help myopia to keep on increasing. This is one of the visual functions that we can work with the vision therapy.

    Besides all it has been said before, if the myopic person with few diopters (less 1 diopter), removes her eyeglasses in order to perform that near work, she will help her visual system (specifically, her ciliary muscle and her crystalline lens -8-, structures that are responsible for focusing works the right way) not to be stressed. In the case of a bigger myopia, she would need another pair of eyeglasses with less degree of myopia, in order to work at near with it without performing unnecessary effort. Although it is totally proved that the use of near eyeglasses with less refraction is useful in order to reduce the myopia or to stop it, it improves the environment factors without a doubt.

  • Many people choose the solution that “will put an end” to myopia, tired of using eyeglasses or contact lenses during much time, resorting to Refractive Surgery. This solution is given by ophthalmologists (not by optometrists). But I have to let you know that not all patients are suitable for this procedure. What I advice you is to go to a clinic specialized in this kind of surgery and that after a complete ocular exam, they advice you your best option.
  • In the case someone wants to “reduce myopia” without getting into the operating room, there exists the option of a treatment performed with semi-rigid permeable contact lenses, called ORTHOKERATOLOGY or “corneal refractive therapy”. This is performed by optometrists. This technique consists of leveling little by little the excess of myopic corneal curvature (when the main cause of the myopia is the cornea), until the point of best vision is obtained, and respecting the health of this ocular structure. Thereby, contact lenses can be used only when we sleep (and not all nights) and then, during the day we can enjoy good vision without wearing any refractive compensation. This option is perfect for those who candidates that need to achieve a certain Visual Acuity without refraction in the medical examination, and they do not want to get into the operating room.

  • Lastly, in order to “prevent” not only that myopia rises or increases, but also to avoid any symptom of visual strain, we should take into an account some RULES OF VISUAL HYGIENE, that are not detrimental to anybody, but, on the other way, can help EVERYBODY, in the carrying out of the near tasks. Again, these rules improve the environmental factors.

But I will explain all these solutions that we can offer the optometrists in later posts.

As myopia keeps on awakening many questions, research is continually performing going on in order to stop its progression and remove it. Nowadays there is an European project called “My Europia”, that is focused on the creation of special eyeglasses with different refraction in the middle of the lens and in the periphery, that causes that the eye to react different ways in order to prevent that progression.

Medicines, vitamins,… Is there anything that I can have in order to stop my myopia?

Until now, there is no medicine that can certainly works in order to stop myopia. The only thing that has been tried in different schools at USA is pirenzepine . But as you can read in the article, this medicine is able to cause myopia to progress slowly but it is not able to prevent that progression. Besides this result, there are still many concerns: secondary effects, what happens if we interrupt the treatment, or how much time would a patient need to be with it. Also, even though this medicine was safe, it had to be removed from some children because it caused ocular irritation. Therefore, there is still much research to do in this subject.

In the other hand, vitamin A, lutein and zeaxanthin are supplements that are said to help eye health. I guess this is like the rules of visual hygiene, if you perform them, they are not detrimental to you; they are vitamins and they are always good for our organism, but personally, I would not support a treatment exclusively on them.

Refractive disorders: Myopia (1).Vision and Symptoms
Refractive disorders: Myopia (2) Kinds and factors
Why does a myopic person’s vision improve when she squeezes her eye lids to a narrow opening?
Refractive visual Disorders. Some clarifications.
Some numbers...