Description of visual disturbances
The eye is man’s most important sensory organ. But it is also very sensitive and can have various defects and diseases which could result in blindness.
Our eye (bulbus oculi) has a spherical shape and is placed in orbit (orbit) in the skull. It is held in place in the eye muscles, which also eye moves in the direction you want to look. It is protected by eyelids and humidification of the tear glands. Eye itself then consists of three layers – fibrous, vascular and nerve. The fibrous layer (tunic fibrosis) is situated on the surface of the eye and is comprised of the cornea (the cornea) and sclera (sclera).
Cornea
Located at the foremost part of the eye and is perfectly colorless and transparent. Above the eye is slightly arched. It has a protective function – when the irritation will blink. Since the cornea passes all light rays, which then fall on the retina, it is necessary to smooth and unbroken. However, if the modified example, various inflammations, light that passes through it is refracted in a different direction than it should, and one sees a blurred. This defect is known as astigmatism and in our population is relatively abundant.
Another defect of the cornea can be called. CORNATE Arcus senilis, which occurs in older people or people with excessive fat intake. In this defect cornea is bordered by a gray ring on the periphery.
sclera
Another part of the eye, which in normal view can be seen. It is white in color and clamped to the extraocular muscles that move the eye with its contraction in all directions.
The second layer of our eyes is a vascular layer. It belongs to the choroid (choroid), ciliary body (corpus ciliary body) and iris (iris).
choroid
As the name suggests – it comprises a plurality of vessels, having a maintenance function. Blood that is supplied arterioles (arteries) contains oxygen and nutrients, which are cells of the eye transmitted and exchanged for nitrogen ohličitý and waste products of metabolism. This blood deprived of important nutrients then head veins (Vena) into the lungs. The supply of nutrients to the eyes – just like for any other organ in the body – vital. Therefore, it can be an eye after various injuries in which a broken blood vessel supply, irreversible damage to decreased vision and blindness. A similar situation could arise in glaucoma (glaucoma) when it is elevated intraocular pressure and fluid is unable to drain. This damaged not only supply but mainly retinal cells that are oppressed and their functions gradually decline.
ciliary body
Ciliary body is another part of the eye and its function consists in suspending the lens. If we did not, the lens could not be fixed in one place. Further, also it has the ability to contract and relax and thereby vyklenovat lens. This makes it possible to focus on nearby objects. Ciliary body is innervated by special fibers, for which you can not focus when fatigue melee. It can also happen in blocking the transfer of these substances by various drugs.
Iris
The iris is the colored part of the eye that is looking into the faces to be seen at a glance. They mounted thereon muscles which alter the translucent hole – pupil – which the light passes into the eye. Again they are innervated by the special fibers, which may be drugs or various other chemicals block.
Retina
The retina is the deepest layer of the eyeball. It consists of several layers of cells – rods andcones. Now we suppositories determine what color we see. For normal color vision we need three kinds of cones for the primary colors of the light spectrum. But if any kind of suppositories missing man suffering from so-called color blindness. Cells that make up the retina through various other cellular connections gradually converge to the optic nerve that goes through the skull and into the brain. In the brain phosphenes they have not run as nerve, but as a so-called track – is part of the brain matter, and is composed of nerve cells (neurons). Thus it comes to the area of the brain where visual stimuli equip a sensation. However if this pathway is interrupted (like inflammation or breach of retinal cells injury), can lead to blindness, to one or both eyes. Blindness but can also cause defects such as gray and glaucoma, which account for more than half of blindness. In poor countries, the reason and inadequate nutrition. Blindness can be congenital. Such cases account for about 3% of all blindness and are caused by delayed or faulty development of the individual parts of the eye.
Lens
Another body is the lens, which is located in front of the eye and its function is the refraction of light that has passed through the cornea, iris gap (ie pupil) to its front surface. The lens refracts light to specific locations on the retina, which then creates an image. Because the necessary passage of light therethrough, is important as in the cornea that is transparent. But this is violated when cataracts, where the lens is cloudy, light rays through it can not properly go through and you may even lead to blindness. Each lens also has its fragility, in which the image is sharp. If however this value is deviated, a person suffering from myopia or hyperopia.
Myopia
Nearsightedness (myopia) can have two reasons. Be the lens has increased fragility and rays of light pass through it impinge on other sites retina (actually crossed in front of her). Or does the eye completely spherical shape – longer – and that is the path of the beam shortened. Therefore they do not reach one point on the retina (this point would be behind it). A person suffering from myopia but may have a combination of both.
Farsightedness
Farsightedness (hyperopia) is actually the complete opposite of myopia. In this eye defect is less refraction lens (light rays cross notionally up behind the retina). Another reason may be again irregularity of spherical shape – in this case the eyeball in the direction of rays passing through shortened.
Risk factors visual disturbances
To protect your eyes as long as possible, it is advisable to avoid risk factors. These are globallypoor nutrition or nutrition-sided with a lack of certain vitamins (vitamin deficiency). Eye defects can cause even work in a poorly lit environment, when the eyes are more stressed. Another risklong-term work on the computer or watching television. It is also necessary to recall that anyeye inflammation can develop and some parts irreparably damaged.
Prevention of visual disturbances
To avoid eye disorders, it is desirable to consume a variety of foods rich in all vitamins (for eyesight is suitable especially vitamin A, C, E, and elements such as zinc and selenium), and important components of food. Furthermore, it should be all the activities that we do, properly lit so as to avoid unnecessary strain on the eyes. On long watching television or computer monitor, we should make or break for a moment to close your eyes. Few people also realize that wearing glasses or lenses that are not entirely satisfactory number of diopters his eyes very weary, and therefore it is necessary to wear these devices only when they are fully compliant.
When wearing contact lenses, it is important to monitor the durability and before each use, follow the manufacturer’s instructions.
But the main prevention is to visit an eye doctor and discuss with him the age of the problems that we have with the eyes. Upon detection of glaucoma it is important to take regularly prescribed medication and attend the measurement of intraocular pressure.
Symptoms of visual disturbances
All eye disorders have symptoms almost identical. It is a gradual deterioration of eyesight, which manifests worse vision to either close or from a distance. Another symptom may be a gradual graying or ztemňování image which patients describe as though the painting was in a fog or looking through a plastic bag. In some diseases disability sees the day well, but in the gloom are unable to focus or distinguish the outlines of distant objects that are otherwise healthy eye visible well.
Treatment of visual disturbances
Nearsightedness, farsightedness and astigmatism are treated with glasses or lenses. In the case of myopia is a diffuser (glasses or lenses that reduces light refraction), with farsightedness then a clutch (refraction diminished). People affected by astigmatism get toric lenses that compensate for corneal curvature. In all these cases it is also possible to laser surgery.
Cataract is nowadays easily solvable operably when defective lens of the eye removed and replaced with artificial. This operation is now performed almost routinely and is the most common procedure in ophthalmology departments. The patient is desensitized eye drops, so it is conscious, and doctors can work together.
Glaucoma is unfortunately not yet possible to heal. It is possible to slow down the process and thus delay progressive slepnutí. It is therefore important that the patient was frequently on the measurement of intraocular pressure, and thus it was possible to monitor what has glaucoma procedure.
How to help treat disorders of the eye
Can help treat proper diet that includes adequate amounts of vitamins and other important substances. It is therefore appropriate to consume adequate amounts of fruits, vegetables and nuts.
Complications visual disturbances
Eye defects are today – with glaucoma – relatively easily resolved. In some cases it is not possible to proceed to invasive methods (e.g., in some patients during cataract surgery), and these patients are doomed to progressive blindness. For use of lenses or in post-operative care, it is also possibleinflammation of the eye, which can damage the cornea or other structures of the eye and vision worse.
Other names: Blindness, Ametropia, hyperopia, hyperopia, myopia, nearsightedness, astigmatism, color blindness, glaucoma, glaucoma, cataracts, optic nerve impairment, disability n. Optic, night blindness, hemeralopia