- Presbyopy reasons
- Presbyopy symptoms
- Treatment of a presbyopy
The presbyopy (senile sight, disease of short hands) the disease arising preferential at people is more senior than 40 years and connected with change of physical and chemical structure of a crystalline lens (dehydration, consolidation, loss of elasticity of fabrics etc.). All these processes lead to accommodation process disturbance.
An eye represents complex complex optical system thanks to which the person can accurately see objects at various distance.
Process of formation of the image which we see begins from the moment of passing of light through an eye cornea (a lens with big optical power). Then, having passed through transparent intraocular liquid in an anterior chamber of an eye, light rushes into an opening in an iris of the eye which diameter depends on amount of this light. This opening is a pupil of our eye.
Lens – the second lens in optical system after a cornea – allows to focus precisely the image on a retina (she perceives in the turned look and transforms the electromagnetic radiation of a visible part of a range to nervous impulses). Further nervous impulses on an optic nerve reach the visual analyzer in a brain where there is a final processing of the received image.
At young age the crystalline lens is able to change the curvature and optical power. This process is called accommodation. In other words, it is ability of an eye to change the focal length thanks to what an eye can see at the same time well both afar and close. With age accommodation is broken. This process is called a presbyopy.
The presbyopy is natural process of aging of a crystalline lens. Similar age changes happen not at once, and gradually.
But there are also other opinions on an etiology of this disease. It is connected with the fact that not all people who reached so-called presbyopic age have a decrease in sight. And also with the fact that it is possible to prevent and liquidate this disturbance.
In one of theories it is proved that at "tension" of eyes with the purpose to see the printed text focus is displaced forward. Therefore the person cannot see the image accurately. Besides, there are pain, discomfort and exhaustion. If it is possible to remove "stress" for a long time, it is possible to return the lost sight.
In other theory it is said that such disease as a presbyopy, does not exist, and such state is caused by one of far-sightedness forms – in that case when decrease in sight both afar, and close is combined.
In the third theory the presbyopy is connected with improper feeding and a lack of vitamins, preferential by groups B, and vitamin C. Treatment in this case is carried out by means of a diet and simple exercises for eyes.
Here the approximate list of complaints with which patients come to the oculist:
- it is difficult to make out small objects close;
- the small print looks low-contrast, letters blur;
- to read the text, it is necessary to take away it on long distance from eyes;
- fatigue and tension of eyes when reading.
Age changes differently take place at people with different pathologies of a refraction. So for example, the presbyopy at people with inborn far-sightedness is shown more often in decrease in sight, both for reading, and for a distance. Thus, the presbyopy aggravates inborn far-sightedness and such patients will need points with big "plus"
People with inborn short-sightedness fall into more advantageous position. "Minus" which the person had all life, offsets age loss of accommodation.
Treatment of a presbyopy:
If you noticed at yourself decrease in sight, it is necessary to address the oculist as soon as possible. The matter is that decrease in sight at the age of 40-70 years can happen not only owing to a presbyopy. So, for example, the diabetes mellitus which is often striking people of this age can also be the cause of anomalies of a refraction. And in that case, the treatment will be begun earlier, the result will be better.
The presbyopy is found when checking sight and a refraction in the ophthalmologist.
Depending on vision disorder degree various points will be necessary for you. If sight afar good, there are also problems only with sight close, it is the simplest to choose glasses for a bliza. In other situation bifocals (with correction for a distance and for a bliza) or two pairs of glasses - one for a distance, another for a bliza will be necessary. Besides, a number of surgical and laser methods of correction of sight is developed today. The doctor will advise operation if he considers that it can be useful to your option of decrease in sight.