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Eye health

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Ametropics

The light arrives to the eye and crosses different transparent structures to the retina, where the luminous energy is turned into electrical energy, which travels to the brain through the optic nerve. The brain is responsible for translating this energy into pictures.

Light rays must exactly focus on the retina to create clear images. On the contrary, we do not see correctly because there is an ametropic: myopia, hypermetropia, astigmatism, presbytia.

Myopia

Myopia impedes to see clearly distant objects, because the image seen is created in front of the retina.
The myopia main symptoms are the difficulty to see far, especially at night, and the need to bring the items closer to see them better.
In these cases, either the myopic eye is longer than usual or the cornea too curved, so images are created in front of the retina.

Miopia

 

Hypermetropia

The image is created behind the retina with hypermetropia. Hypermetropes have to make a continuous effort to adapt the eyes and see the distant objects properly.
The main hypermetropia symptoms are headache, eyestrain and sometimes they have difficult to see close.
In these cases, either the hypermetrope eye is very short or the curvature is very plane, so images are created behind the retina.

Hipermetropia

 

Astigmatism

Astigmatism occurs when an object is focused in different levels. This is caused because the optical surface of the cornea or of the crystalline is not spherical but it has two radius of curvature.
Astigmatism can be associated both with hypermeropia and myopia, and its most representative symptoms are headache and eye irritation.
The astigmatic eye has not got a spherical cornea and it focuses in different levels.

Estigmatisme

 

Presbytia

Presbytia, also called eyestrain, means a decrease in the focusing ability. It causes difficulty to read or to work with close objects. It usually appears after 40 or 45 years.
Over the years, the loss of elasticity and strength of the ciliary muscle and the loss of the flexibility of the crystalline make that the eye loses its accommodation ability to see close.
The presbytia symptoms are eyestrain, sleepiness while reading or impossibility of doing close activities for a long time. Moving the text away from the eyes or bringing it closer to an intense light source to read better are other obvious symptoms of presbytia

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