Description astigmatism
Astigmatism is an eye defect caused by faulty or distorted corneal curvature. It is a disease relatively widely represented in our population (about 10% of people suffer from this defect) with different sizes disability.
When we speak of astigmatism, we mean usually eye defect. The same will be true in this text about him. But it is important to distinguish the concepts that are related with astigmatism.Astigmatism as such is in fact a physiological characteristic of the eye which says that the cornea is not perfectly symmetrical and circular, but slightly elliptical. If cornea is perfectly spherical rays that pass through it, would the retina appear as a dot. Such physiological and astigmatism say it has almost everyone. It is therefore quite normal and does not belong to eye defects. However, if the modified corneal curvature such as various inflammations, this is already the irregular astigmatism which is eye condition. This defect also called refractive aspheric.
To understand the astgmatismu it is necessary first to describe how our eye (bulbus oculi). The eyes are the sensory organ, which provide one of the most important human perceptions – sight. Eyes are paired and are stored in the skull in a place that is called the orbit (orbit). It consists of three layers, which are further subdivided into individual components of the eye.
The layer closest to the surface is called the tunica fibrosa (its institutions are the cornea and sclera), the layer below the tunica vasculosa (this layer include the choroid, ciliary body and iris) and the layer, which is the deepest as the tunica nervosa (the sole authority of the retina) . From the retina based on optic nerve (optic nerve) that passes through a hole in the bone to orbit inside the skull. This nerve among the twelve cranial nerves and his task is to bring visual stimuli to the brain. Only in him is itself sensation rigs.
Tunica fibrosa layer is cornea (cornea). It’s perfectly clear, colorless body of the eye, which is also the task of protecting the eye. Although the transparent cornea, contains small nerve fibers that are sensitive to different stimuli. It touches the cornea is recorded and will be closing the eyes (blink).This reduces the potential risk. The cornea protrudes above the sclera and its shape resembles a watch glass. It passes through the cornea of all the images that pass through the eye to the retina, which then forms the signal going to the brain. In the brain, then think of the picture. Therefore, it is important to complete clarity, transparency and proper curvature, which deforms the image in any way.
As already stated, because astigmatism cornea when changed, it is not possible for light rays which pass through it met the retina in focus as they should. Therefore, people who suffer from astigmatism to see blurred near and far.
Risk factors astigmatism
Risk in the case of astigmatism various inflammations or even injuries which are affected eyes.Since astigmatism may be cause by mechanical action, occurs in abundance and in people who suffer from various allergies. These people and rub my eyes to a greater extent and that the long-term effect on the cornea, her own way slightly deformed. Then there can be very various errors in its curvature, which then causes astigmatism. What will be its measure, it depends on the cornea.
prevention astigmatism
Prevention of astigmatism is an effort to cure inflammation early in his eyes. Therefore, if any inflammation of the eye, we know it is always better to consult an ophthalmologist who naordinuje treatment. It should be borne in mind that the eyes are very sensitive organ. And because the sight is practically the most important sense for humans, we should take care of them properly.
It is also advisable to avoid activities that could cause injury to eyes. Allergy sufferers should also pay attention to your eyes too neprotírali. The so-called itchy eyes is better to solve the allergist or application of drops that eyes moistened, and are suitable for this purpose.
symptoms of astigmatism
The main symptom is blurred vision at both near and distance. Astigmatism is often associated with other eye disorders such as nearsightedness (myopia) and farsightedness (hyperopia). Patients are also not able to distinguish contrasts between differently curved lines in the control of special tables.
treatment of astigmatism
Astigmatism is nowadays quite well to correct the condition. There are several treatment options.The patient can either wear toric lenses that compensate for corneal irregularity. Their use is achieved and correct refraction of light on it and thus sharper vision. Light is therefore refracted into focus at the retina as the physiological state. Many toric lens also depends on other defects of the eye. These lenses can also would diopter, because patients often suffer from astigmatism or farsightedness simultaneously blízkozrakostí. When choosing the right lens they first deployed without added toric lens diopters. If and when its application is blurred vision, the doctor tries his eyes and adds the results to the individual lenses more diopters.
The second option is a spectacle correction of cylindrical lenses.
Another variant is also operations. When the cornea is laser smoothed and thus disappear the wrong curvature. But patients can still see blurry if you suffer from any other eye condition such as farsightedness or nearsightedness. These defects are caused by varying the length of the eye or incorrect Refractive lens and cornea laser surgery on them has no effect.
How can I help myself?
In this eye disorder is perhaps the only means of adherence to preventive measures. Because the eye is but a very sensitive organ, it is always better to seek professional medical help.
complications astigmatism
Astigmatism is relatively nekomplikující the disease. It is possible that when the treatment was given to the eye inflammation, for example in the application unadjusted lenses or lenses which expired shelf life. It is therefore necessary to respect the manufacturer’s recommendations.Complications can arise even after laser treatment. This is an operation and may therefore lead to various post-operative problems such as the inflammation or infection.
Other names: Irregular curvature of the cornea, irregular curvature of the eyeball, cylindrical eyesight, regular astigmatism, irregular astigmatism, astigmatism according to the rule, aspherical refractive eye defect
