Ametropia is a violation of the reflex functions of the eyeball. This violation can manifest itself in the form of hyperopia or, on the contrary, myopia. The disorder of the properties of the retina in light refraction and image fixation can be observed not only in adults, but also in children.
Causes
Causes contributing to the occurrence of ametropia (this is myopia and farsightedness):
- Mechanical injuries.
- Disorder of the functions of vision can occur due to damage to the retina due to various external influences: car accidents, bruises while playing the ball, attacking a person for the purpose of an attempt.
- Systematic inflammation of the eye.
- Inadequate illumination of the room.
- The lack of vitamins in the body.
- Hereditary predisposition.
- May develop due to age-related changes.
- Long stay in front of the computer.
- Intrauterine disturbance in the formation of eye muscles.
- Eyeball muscle weakness is one of the main causes of ametropia.
It should also be noted that visual impairment in babies progresses much faster than in adults. Therefore, parents must undergo a scheduled examination annually with a specialist.
Symptoms
With ametropia in children, squinting is observed, visual acuity decreases, and there is a significant deterioration in visual comfort. With hyperopia, the patient may be bothered by eye fatigue, pain in the orbits and forehead. Frequent conjunctival hyperemia or accommodation asthenopia is noted.
If hyperopia is not corrected in time (usually done in childhood), this can cause the development of amblyopia and convergent friendly strabismus. The most striking and frequently encountered symptoms of ametropia, ophthalmologists call the following:
- asthenopia due to rapid eye fatigue;
- motion sickness while riding;
- a feeling of twitching of the eye;
- double vision
- frequent dizziness;
- headache;
- the patient often rubs his eyes;
- shaking his head for a better view of the subject.
Ametropia can also manifest myopia or farsightedness. Therefore, it is worth saying that the symptoms directly depend on the types of ametropia. If strabismus is manifested, vision is reduced, you should immediately consult an ophthalmologist for advice. In principle, this pathology is the most common among eye diseases; it occurs not only in adults, but also in children.
Spectacle correction
Point correction is a traditional and modern method of correcting ametropia. Glasses are a special medical device that consists of lenses and frames. Depending on the type of refraction pathology, different types of lenses are chosen, with ametropia of different levels, the visual power of the lens also changes.
Indications for spectacle correction of vision:
- a high level of myopia;
- high level of hyperopia;
- astigmatism from -6 to +6 diopters;
- presbyopia - a decrease in near visual acuity that appears after 40-45 years is a direct indicator of the aging of the body;
- childhood;
- intolerance to contact lenses;
- the inability to perform surgical (laser) correction of ametropia.
Contraindications to spectacle correction:
- risk of possible eye injury (sports, outdoor games);
- professions requiring a fairly large field of vision, such as pilots or firefighters;
- anisometropia (with a difference of more than 2 diopters);
- individual intolerance of points.
Lens correction
Lens correction of vision - a change in refraction using lenses. They call contact due to the fact that they directly have contact with the cornea - the colorless shell of the eye. The contact lens is a small lens in the form of a bowl, which is inserted behind the lower eyelid and is adjacent to the cornea. To date, contact correction has gained a very extensive promotion, because it easily makes it possible to engage in active sports, does not limit the field of view, and does not exert pressure on the bridge of the nose and ears, unlike glasses.
There is a position that lens correction is only suitable for myopia, but it is not. All sorts of refractive pathologies can be corrected using lenses. Just for certain pathologies, for example, with presbyopia, their use is meaningless, because patients suffering from presbyopia wear glasses only for work near or for reading.
Today, lenses are made from a material (silicone hydrogel) that easily passes oxygen to the cornea. The patient can choose the lenses that are optimal for him: hard or soft (mostly use soft), in addition, the lenses are separated depending on the wearing time (two-week, monthly, for 3 months, etc.). One-day lenses are widespread, which in the evening, a person takes off, throws them away, putting on new ones the next day.
Contraindications to the use of lenses:
- significant refractive errors ;
- regular conjunctivitis and blepharitis;
- demodicosis of the eyelids (the presence of tick parasites).
Laser treatment
Laser vision correction - correction of eye refraction through a change in the thickness of the cornea using an excimer laser. By changing the thickness of the cornea, its visual power is changed, as a result of which the light is focused on the retina, and the person clearly and clearly sees the objects around him. Laser vision correction is considered a progressive direction in current ophthalmology.
There are 2 types of laser eye ametropia treatment: photoreactive keratectomy (PRK) - an excimer laser eliminates shallow layers of the cornea, changing its thickness. With the help of PRK, one can correct myopia (up to -6 diopters), hyperopia (up to +3 diopters), astigmatism (up to -3 diopters).
After PRK, there is a rather long recovery period - up to several months, specialized drops should be instilled into the eyes. The advantages of PRK are the absolute painlessness of the operation, the short-term period of laser exposure, and the stability of the results.
LASIK (electro laser laser keratomileusis, Lasik) - involves a combination of microsurgical and excimer-laser stages. During the procedure, under the guidance of a doctor-ophthalmologist, a section of the cornea is bent using an automated special medical device - microkeratome. Next, the corneal thickness previously calculated using computer technology is removed by a laser. The turned-off site returns to the place. The procedure takes 1-1.5 minutes. After a couple of hours, you are allowed to return to your normal lifestyle. With LASIK, the correction of the highest levels of ametropia is likely.
Indications
This type of correction does not help with all diseases. Indications for laser vision correction:
- different visual acuity;
- professions requiring instant response;
- desire of the patient himself.
Contraindications
Contraindications:
- age less than 18 years;
- progressive myopia;
- pregnancy and lactation;
- general serious illnesses of the body (for example, diabetes mellitus - a violation of glucose metabolism);
- acute infectious diseases.
A number of eye diseases:
- inflammatory in nature;
- cataract (lens fogging);
- glaucoma (increased intraocular pressure);
- history of retinal detachment.
Prevention
Prevention of ametropia (this is myopia and farsightedness) helps prevent the development of visual impairment. The following methods are used to prevent the occurrence of visual impairment:
- Scheduled examination by an ophthalmologist. Inspection by a specialist allows you to control the state of vision of the child, and also prevents the development of dangerous complications.
- Daily gymnastics for the eyes. Using special exercises to strengthen the muscles of the eye allows you to increase blood circulation in the tissue and relieve fatigue while working at the computer or reading a book.
- Correct load distribution on visual analyzers.
- The use of vitamins and minerals. Deficiency of vitamins A and C is one of the reasons for the decrease in visual acuity. Reducing the length of time in front of a computer.
- The use of additional tools to ensure optimal illumination of the room.
- Daily walks in the fresh air.
- Use of manuals with large and clear print.
Compliance with all of the above recommendations will allow you to maintain good vision for a long time and prevent the development of ametropia (this is an eye disease).