There are many eye diseases that lead to partial or complete loss of vision.Some of them are studied well enough and do not present difficulties in treatment. Others, despite the many innovative achievements of medicine and ways of diagnosing diseases, remain an unclear spot and are almost not subject to cure.Among such conditions is a pathology called amavroz.
Content
1Definition of disease
2Types and Classifications
3Causes
4Symptoms
5Possible complications
6Diagnostics
7Treatment
7.1Medicines
7.2Surgically
8Prevention
9Video
10conclusions
Definition of disease
If you translate the term "amavroz" from the Greek language, the result will be the word "dark which best reflects the essence of the pathology - lack of vision.The causes of this condition are not fully understood, although the lesion of the optic nerve and retina is indicated as the root of the problem.
The etiology of such lesions is often hereditary and is caused by a mutation of 18 genes that encode different proteins in the retina.
The incidence of such manifestations is 3: 10, 00, and of the total number of hereditary retinopathies (vascular lesions leading to visual impairment) does not exceed 5%.Nevertheless, the disease almost does not give in to treatment, and a child with a hereditary amaurosis, by the age of 10, loses sight completely.
To the same category include the temporary manifestations of amaurosis, which last no more than 10 minutes. and can manifest themselves both on one and both eyes.
Types and Classifications
Distinguish the following forms of the disease:
Transit(or transient) amaurosis is characterized by impaired or complete loss of vision. In this condition, loss of visual functions is temporary, and their recovery is possible spontaneously or under the influence of medications;
Amaurosis Lebera(congenital) is due to genetic disorders. In the cells of the retina (rods) contains the main visual pigment rhodopsin, the formation of which can be broken with various kinds of mutations. Since the formation of visual images occurs on the basis of nerve impulses, which are impossible without a sufficient number of rhodopsin, there is a violation of visual perception.
With transient amaurosis, various types of symptomatology may arise: anterior ischemic oculopathy, photosensitive retinopathy, transient monocular blindness.
Causes
The main mechanism of visual impairment in the presence of Leber's amaurosis is malfunctions in metabolic processes occurring in cones and rods. The consequence of such disorders is always the defeat of photoreceptors followed by their complete destruction. The immediate cause of these changes is different, because it can be caused by a mutation of different genes:
The presence of the RPE65 genebecomes the cause of insufficient synthesis of rhodopsin. Such a mutation is observed in most cases of the disease;
The presence of the LRAT genecauses the development of degeneration of photoreceptors;
The presence of the CRB1 geneaffects the embryonic development of retinal pigment epithelium and photoreceptors;
The presence of the CRX genemay cause insufficient embryonic development of photoreceptors, loss of control of their condition in the adult period.
When a transient form of the disease occurs, visual impairment occurs in the absence consistency in the functioning of various areas of the optic-neural analyzer, as well as in violation of the passage nerve impulse. Such disorders in work can be caused by a number of reasons:
Disorders of cerebral circulation(ischemic attacks, strokes);
Tumors in the brain, pressing on the optic nerve or centers of the visual analyzer;
In case of congenital disease, the transmission of the damaged gene passes through an autosomal recessive type. This means that both parents must have a defective gene in one chromosome. In this case, the probability of producing a sick child is 25%.
Symptoms
To suspect the presence of a severe congenital form of the disease can be already in childhood:
The baby does not even react to objects that are very close;
A child is not able to fix a sight on a certain object, and his view always wanders;
Almost no reaction of the pupil to stimulation by light;
The child's eyes perform constant involuntary movements in different directions.
In addition, almost always these children develop strabismus, keratoconus (the shape of the cornea takes an overly convex shape), cataracts, astigmatism, hypermetropia, myopia. Defects can occur either singly or in combination with each other. At a low speed of the process, poor eyesight in such children can persist up to 9-10 years, but already from this age they are blinded.
If the disease is transient, the symptoms may differ depending on the cause, but there is always a sharp deterioration in vision:
When cerebral circulation is disturbed, in addition to loss of vision, dizziness and weakness, disorientation in space;
In cerebral trauma- loss of visual fields, nystagmus (involuntary oscillatory movements of the eyes), inability to focus the view;
With endocrine diseases- edema of the orbital fiber, oculomotor muscles, double vision and pain in the eyes, exophthalmos (feeling of protrusion of the eyes);
In severe poisoning- loss of visual fields, disorientation in space and confusion, blindness;
With oncological diseases of the brain- headache and eye pain, nystagmus, disruption of accommodation;
With migraines- during the attacks there is no vision completely.
For children with Leber's disease is characterized by increased traumatic and clumsiness in behavior. At birth, loss of vision is not complete (except in rare cases), but the progression of the disease is steadily leading to its loss.
Possible complications
Poor vision in childhood always puts an imprint on psychological development.Even such seemingly familiar visual defects as nearsightedness and farsightedness can significantly complicate the life of a little man.
Impaired visual function in Leber's amaurosis causes the child to have the following negative consequences:
Retardation of psychomotor development;
Decreased motor activity;
Muscular hypotension.
The prognosis for children with this disease is almost always negative (in 95%), since modern medicine does not yet have the means to cure it.
In the transient form of the disease, timely and adequate treatment can give certain positive results, but in the absence of diagnosis of the disease in the early stages, the probability of complete loss of vision.Success depends entirely on the severity of the lesions at the initial stage of therapy.
Diagnostics
To make a diagnosis you need a thorough diagnosis:
Examination of the patient and collection of anamnesis data;
Visometry (visual acuity check);
Ophthalmoscopy(examination of the fundus);
General and biochemical examination of blood;
Verification of visual and neurological reflexes;
Magnetic resonance study.Conduction of ophthalmoscopy
If suspected of amaurosis, Leber is scheduled to perform genetic tests. Differential diagnostics with diseases is also mandatory: optic atrophy, retinitis pigmented retina.
Treatment
The effectiveness of treatment depends entirely on the form of lesions and the degree of development of the disease at the time of detection.
Medicines
Leber's amaurosis is not specific for today.Experimental development of genetic engineering for the treatment of patients with type 2 amaurosis is at the stage of clinical trials and there are already first successes. However, no progress has been made with regard to other types of disease.Measures of maintenance therapy are the intake of vitamins, intraocular injections of vasodilator drugs, as well as spectacle correction.
Dibazol is a vasodilator
With the transient form of the disease, the therapy scheme depends entirely on the etiological factors:
In violation of blood circulation, injuriestreatment is carried out by blood circulation improving agents, diuretics, nootropics, hypotensive drugs, capillary stabilizing agents;
With oncological diseaseseffective surgical interventions, as well as chemo- or radiotherapy;
In toxic poisoningdetoxification therapy is carried out, which, if used in a timely manner, can completely eliminate the violations;
With endocrine pathologiesafter a careful examination, a correction is made with the use of hypoglycemic drugs and hormone replacement therapy;
With migrainestreatment consists in taking antispasmodics and antimigrenous drugs.
Amavroz is a complex pathology, which, nevertheless, is capable of progressing with irreversible consequences. Therefore, vision should be timely and adequate after extensive diagnosis.
Surgically
The use of surgical techniques in the treatment of disease can be effective in the following cases:
The presence of compressive tumors in the brain or near the optic nerve;
Necessity of correction for craniocerebral injuries.
Among the surgical techniques can be attributed and methods of treatment for the introduction into the eye of new developments in genetic engineering: cloned gene and adeno-associated virus (preparation AAV2-hRPE65v2). The virus is needed as a gene delivery vector to the desired site. Clinical trials are conducted in one of the clinics in Philadelphia (similar - in Naples). According to the testimony of American scientists, the effect of such treatment persists for years, which opens up good prospects for further research.
Prevention
There are no preventive measures for Leber's amaurosis.To prevent a child from developing this dangerous disease during pregnancy planning, it is recommended that both parents make a thorough genetic diagnosis. Of course, in the case of the presence of similar pathologies in one of the relatives.
To prevent the transient form of the disease, you should first of all monitor the level of the overall health of the body:
To refuse from bad habits;
Monitor your diet, giving preference to healthy food before delicious;
Avoid hypodynamia, because it is the main enemy of normal blood circulation and the cause of many pathologies in old age;
In a timely manner, treat any diseases, while avoiding self-treatment and observing medical recommendations;
Regularly undergo preventive examinations, as well as visit a doctor with initial signs of malaise.
Video
conclusions
Timely identified disease always has maximum chances of recovery, and amaurosis is no exception. And although in the case of congenital pathology, the prognosis is extremely unfavorable, yet the probability of maintaining a minimal vision is present.At the congenital form the child completely loses visual function and to it the invalidity on sight is appropriated.
In the transient form of the disease, everything depends on the timeliness of detection and selection of the correct therapeutic tactics. Adequate and timely treatment has all chances for success.
