Amblyopia is a functional( non-organic), reversible vision disorder that occurs more often in childhood and adolescence. Amblyopia can not be corrected with the help of glasses and contact lenses, does not pass by itself and is often a secondary visual impairment.
What is it? When amblyopia eyes of the person see different pictures, they are differently involved in the visual process: one eye, as it were, sees not completely, the brain can not reduce the visual picture in both eyes to one common, as a result, the work of one eye is completely or partially suppressed, brokenthe volume perception of objects, the order of their location in space, the size of objects are also estimated inadequately.
It is due to the slow development of the visual zones that the treatment should be performed up to 7 years, while the formation of the eyes is carried out. In connection with the deterioration of the environment and, as a consequence, the presence of congenital pathologies, the disease is becoming increasingly prevalent especially in children.
What is amblyopia - the causes of
Why does amblyopia occur and what is it? Typically, amblyopia develops in childhood. The main cause of amblyopia is strabismus. But it can also develop with severe nearsightedness or farsightedness, nystagmus( involuntary rhythmic vibrational movements of the eyes), and also with astigmatism.
The risk factors for developing amblyopia include the presence of strabismus, a high degree of ametropia, states contributing to deprivation( in this case, deprivation means a lack of visual stimuli by the visual organ) at the age of 6-8 years. In addition, the risk factors include:
- prematurity;
- birth weight deficit;
- retinopathy of prematurity;
- cerebral palsy;
- mental retardation;
- family history of anemia with anisometropia, isometropia, strabismus, amblyopia, congenital cataract.
Especially often amblyopia develops in people with a difference in the optical power of the eye more than three diopters. Sometimes the cause of amblyopia becomes an obstacle for the passage of light rays. It can be scar, thorn, cataract, especially congenital, ophthalmoplegia( paralysis of the muscles of the eye), ptosis( omission of the eyelid).
Amblyopia can develop in those who, in poor vision, do not wear glasses or lenses, whose eyes do not know what it means to "see well."
Classification of
There are several types of amblyopia, each of which has certain characteristics:
- Refractive amblyopia is the most common form, it is also called optical. The optics of the eye is broken - rays of light of the eye refracts unequally. It arises from neglected astigmatism and rapidly progressing farsightedness. Doctors, as a rule, appoint wearing glasses or contact lenses. In childhood, the disease is treated very successfully, most importantly - do not delay the start of treatment and do not hesitate to wear glasses.
- Disbinocular amblyopia develops when the binocular vision is disturbed by strabismus. One eye may suffer from severe strabismus. When this happens, the brain "turns off" this eye and the visual function completely falls on the other eye.
- Psychogenic amblyopia .Most often this type appears with hysteria. There is a sudden illness, often due to a very strong emotional shock. It is treatable, but with timely therapy. In this case, a patient may be recommended to visit a psychologist, as well as taking sedatives.
- Deprivative amblyopia develops when cataracts, a throat or similar disease develops, and causes eye problems. Sometimes deprivational amblyopia affects both eyes.
Degrees
At present, five degrees of amblyopia are distinguished, depending on visual acuity reduction:
- I degree - very weak amblyopia, visual acuity 0.8-0.9.
- II degree - weak amblyopia, visual acuity 0.5-0.7.
- III degree - average amblyopia, visual acuity 0.3-0.4.
- IV degree - severe amblyopia, visual acuity 0.05-0.2.
- V degree - very strong amblyopia, visual acuity Below 0,05.
The degree of development of the ailment of the human visual organ largely depends on the level of development of concomitant diseases.
Symptoms of amblyopia
The pathology is that the sick eye sees a kind of fuzzy picture that does not coincide with the one that the healthy eye perceives. As a result of this dissonance, the brain can not combine both pictures into one, because of which the weaker eye is gradually turned off from the process of image analysis and active work. As a result of this forced inactivity, there is a gradual decrease in vision on it.
The specialists identified the main symptoms of amblyopia:
- Poor vision( one, both eyes);
- Strabismus;
- When reading, for example, a patient with amblyopia can tilt his head or close one eye;
- Impaired orientation in new unusual conditions, poor coordination of movements.
In most cases, a small amblyopia patient does not even suspect its presence. Sometimes it happens, the patient accidentally reveals a different optical power of the eyes, but in the initial stages of this disease it is almost impossible to determine.
Diagnosis of amblyopia
Before you figure out how to treat amblyopia, you must correctly diagnose. Therefore, in order to correctly diagnose amblyopia, it is necessary to perform a comprehensive ophthalmological examination. For this purpose, ophthalmoscopy, biomicroscopy, and examination of the fundus are performed.
General information on the state of vision is obtained with the help of ophthalmological tests: visual acuity checking without correction and against its background, color testing, perimetry, refractive test. Depending on the reduction in visual acuity, the degree of amblyopia is determined.
To examine the structures of the eye with amblyopia, ophthalmoscopy, biomicroscopy, eye day examination with a Goldman lens are performed. To determine the transparency of refractive media( the lens and vitreous body), the eye is examined in transmitted light. When the media are opaque, their condition is examined using the ultrasound of the eye.
Treatment of amblyopia
First and foremost, it should be noted that the younger the patient, the greater the possibility of obtaining a positive outcome of amblyopia treatment, he has. To treat amblyopia in adults is much more difficult. The thing is that it is almost impossible to make the fully formed components of the visual analyzer work correctly. Visual problems, not cured in childhood, are unlikely to be eliminated in the adult period of life.
The best way to achieve and maintain a high visual acuity is to develop a normal binocular vision. For successful treatment it is necessary to determine the type and eliminate the main cause of amblyopia. Most often such are deprivation and oppression of binocular vision.
One of the traditional and basic methods of treating amblyopia is occlusion - turning off a healthy eye from an act of sight. For this purpose, use special plastic occludors, attached to the spectacle frame. In combination with occlusion, methods of light stimulation of the retina( stimulation of the central fossa of the yellow spot with white or monochromatic light of a pulse lamp, defocused beam of a helium-neon laser, employment of specially selected table games - mosaic, cubes, drawing), electric stimulation of the optic nerve of the amblyopic eye,
In general, treatment of the disease should be carried out under the constant supervision of a doctor who will monitor the effectiveness of the selected therapy, as well as its effect on a healthyeye.
Forecast
If treatment is started before the age of five, then, as a rule, normal vision can be restored. However, even in this case, the child may have a violation of perception of the depth of objects. When treatment is started after 10 years, only partial recovery of vision can be expected.
Low result of treatment is often associated with ignoring the recommendations of the doctor's parents, unwillingness to wear glasses to the child, a long search for a suitable specialist. As a result of these actions, time is lost, and pathology correction should be carried out as early as possible.