At a miopiya the image falls not on the established retina area at all, on the contrary, it settles down in the plane which is before it. For this reason people with short-sightedness perceive surrounding subjects the indistinct. All this is connected with that there is a discrepancy of force of optical system to length. Most often at short-sightedness there is an increase in an eyeball (so-called axial short-sightedness).
Short-sightedness and its types
Miopiya happens congenital and acquired. Thus distinguish a miopiya:
- Early acquired (preschool age).
- Acquired at school age.
- Late acquired (adults).
Short-sightedness, to all other, can also to progress. Miopiya most often develops because of three factors: the person makes visual work at a short distance, heredity and owing to weakening of an external cover of an eye. Thus the task of the doctor to define what of the above-stated factors is fundamental and influences development of short-sightedness to correct treatment and to eliminate whenever possible these reasons. At this disease of people can see ideally close, and here with subjects at distance it is much more difficult.
Actually it is quite serious illness as at short-sightedness of people can simply on simply in time "not notice" danger: the open hatch or the coming nearer transport.
Experts allocate three degrees of this disease:
- To three dioptries is a weak degree.
- To six dioptries – average degree.
- More than six dioptries – high degree.
The last from the given – high degree – is not limited in indicators. It can reach enough big figures: people meet sight of both 15 dioptries, and 30 dioptries, and even above.
At short-sightedness people need to wear glasses that they saw afar. If a miopiya more than 6 dioptries, points are appointed to continuous carrying and not just to look afar. Unfortunately, points not always cannot help the person when he has too "bad" sight. Generally this problem is connected with irreversible changes in covers of eyes.
Short-sightedness at children
At children the visual system all the time is in development. Being born, the kid cannot brag of an acute eyesight, besides it has no communication between the right and left eye. Maturing, the kid acquires more advanced visual system. It is very important to parents to watch that sight did not decrease at preschool age.
To secure the kid, InfoAdvisor.net recommends strongly to watch that he spent less time behind the computer or in front of the TV. If suddenly sight started worsening, it is worth visiting the doctor, as it, perhaps, an accommodation spasm. Further it can pass into the progressing miopiya. Experts claim that the most serious disease is an ambliopiya when sight decreases in spite of the fact that the person wears glasses.
Generally progressing short-sightedness meets at school age when children actively grow. Thus the number of children at whom sight falls annually increases.
It is also worth noting that there is a false miopiya – when at the age of four-six years at kids the excess tension of accommodation begins. There are some periods when parents need to be very attentive to sight of the child:
- When the child goes to the first class. Today this period affects age from five to seven years. The beginning of study is not only is disturbing, but also an occasion to show consideration for health.
- Transition from younger school to average. This age, about ten-twelve years, is very important as puberty begins. From here awkward age and emotional and unstable behavior.
- Termination of high school. Fifteen-seventeen years: time of examinations, graduation party and beginning of student's life.
These three periods can be followed by identical symptoms: in the evening, fast fatigue, after tension of eyes (reading, viewing of the TV, work behind the computer), develops "eye pain" - so children call fatigue and an overstrain of eyeballs. All this very dangerous symptoms as after them at children problems with sight quite often begin: in particular, its sharpness considerably decreases.
Today various treatment of a miopiya is developed. Besides there is also preventive charging which is desirable for carrying out several times a day. Experts even thought up the computer program which can train sight.
Correction of a miopiya
To correct a poor eyesight, in particular, short-sightedness, today possible in two ways: glasses wearing and carrying contact lenses. By means of these optical adaptations it is possible "to force" to be leveled light beams and to make so that they were crossed where have to – as well as at people who have absolute sight. Unfortunately, neither points, nor contact lenses will never relieve of a miopiya. They can only improve sight for the period of carrying these adaptations, no more.
Now short-sightedness is curable. Today there are already more than twenty methods of treatment of a miopiya.
Treatment of a miopiya
In spite of the fact that there are many methods of treatment of short-sightedness, there are some ways which proved only from a positive side. Also resort to them most often. Here five most known methods:
- . The most effective, popular and safe method. Resort to it not only at a miopiya, but also at far-sightedness, and an astigmatism. Sight improves thanks to change of a form of a cornea by means of a laser beam. In principle, procedure simple, is carried out only in some minutes. By means of this way it is possible to eliminate short-sightedness even to 15,0 dioptries. Laser correction is allowed aged people from 18 to 45 years, but the final decision is made nevertheless by the ophthalmologist.
- Lensektomiya. At refraction replacement of a crystalline lens (lensektomiya) the doctor deletes a transparent crystalline lens, and places on its place an artificial lens with the necessary optical power. This method is used for treatment of a miopiya to 20 D. This operation is performed generally when the person cannot accurately distinguish subjects which settle down from him at different distance. Lensektomiya more difficult operation, but takes it no more than 20 minutes.
- Implantation of lenses. Thanks to implantation of faktichny lenses it is possible to cure a miopiya even to 25 dioptries thus the crystalline lens remains on a place, but in an eye chamber (either back, or a lobby) will put a special lens.
- Radial keratomiya. By means of small radial cuts change a cornea form, and also its optical power that subsequently improves sight. In this method there are a lot of minuses, among them: duration of the recovery period, not clear forecast of result, probability of complications at physical activities etc.
- Keratoplasty. By means of this operation plasticity of a cornea that influences sight improvements is carried out. Such result is reached thanks to change of a donor cornea (more precisely, its certain layers), and then and its modeling.