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Partial optic atrophy: treatment

Optic atrophy is a disease in which vision decreases, sometimes to the point of complete loss. This occurs when the nerve fibers that carry information about what a person sees from the retina to the visual part of the brain partially or completely die. This pathology can arise due to many reasons, so a person can encounter it at any age.

Important! Timely detection and treatment of the disease, if the death of the nerve is partial, helps stop the loss of visual function and restore it. If the nerve has completely atrophied, then vision will not be restored.

The optic nerve is an afferent nerve fiber that runs from the retina to the occipital visual region of the brain. Thanks to this nerve, information about visible to humans picture, and is transmitted to the visual department, and in it it is already transformed into a familiar image. When atrophy occurs, nerve fibers begin to die and be replaced connective tissue, which is similar to scar tissue. In this condition, the functioning of the capillaries supplying the nerve stops.

How is the disease classified?

Depending on the time of occurrence, there are congenital and acquired optic nerve atrophy. According to localization, the pathology can be:

ascending - the layer of nerve fibers located on the retina of the eye is affected, and the lesion itself is sent to the brain;
descending - the visual part of the brain is affected, and the lesion is directed to the disc on the retina.

Depending on the degree of the lesion, atrophy can be:

initial - only some fibers are affected;
partial – the diameter of the nerve is affected;
incomplete – the lesion is widespread, but vision is not completely lost;
complete - the optic nerve dies, leading to complete loss visual function.

With a unilateral disease, one nerve is damaged, as a result of which one eye begins to see poorly. When the nerves of both eyes are damaged, they speak of bilateral atrophy. According to the stability of visual function, the pathology can be stationary, in which visual acuity falls and then remains at the same level, and progressive, when vision becomes worse.

Why can the optic nerve atrophy?

The causes of optic nerve atrophy are varied. The congenital form of the disease in children occurs due to genetic pathologies, such as Leber's disease. In this case, partial atrophy of the optic nerve most often occurs. The acquired form of pathology occurs due to various diseases systemic and ophthalmological nature. Nerve death can occur due to:

compression of the vessels supplying the nerve or the nerve itself by a neoplasm in the skull;
myopia;
atherosclerosis, leading to plaques in blood vessels;
thrombosis of nerve vessels;v
inflammation vascular walls during syphilis or vasculitis;
disorders of the structure of blood vessels due to diabetes mellitus or promotion blood pressure;
eye injury;
intoxication of the body during respiratory viral infections, when consumed large doses alcohol, drugs or due to excessive smoking.

The ascending form of the disease occurs when eye diseases such as glaucoma and myopia. Causes of descending optic atrophy:

retrobulbar neuritis;
traumatic damage to the place where the optic nerves cross;
neoplasm in the pituitary gland of the brain.

Unilateral disease occurs due to diseases of the eyes or orbits, as well as from initial stage cranial diseases. Both eyes can suffer from atrophy at once due to:

intoxications;
syphilis;
neoplasms in the skull;
poor blood circulation in nerve vessels during atherosclerosis, diabetes, hypertension.

What clinical picture does the disease have?

Symptoms of optic atrophy depend on the form of the disease. If this disease occurs, vision cannot be corrected with glasses. The most basic symptom is decreased visual acuity. The second symptom is a change in the fields of visual function. By this sign, the doctor can understand how deep the lesion has occurred.

The patient develops “tunnel vision,” that is, the person sees as he would see if he put a tube to his eye. Peripheral (side) vision is lost and the patient sees only those objects that are directly in front of him. In most cases, such vision is accompanied by scotomas - dark spots in any part of the visual field. Later, color vision disorder begins, the patient first ceases to distinguish green color, then red.

When nerve fibers concentrated as close as possible to the retina or directly in it are damaged, dark spots arise in the center visible picture. With a deeper lesion, half the image on the side of the nose or temple may disappear, depending on which side the lesion occurred on. With secondary atrophy caused by any ophthalmological disease, the following symptoms occur:

the veins of the eyes dilate;
blood vessels narrow;
the boundaries of the optic nerve area become smoothed;
the retinal disc becomes pale.

Important! If even slight clouding appears in the eye (or both eyes), you should visit an ophthalmologist as soon as possible. Only by detecting the disease in time can you stop it at the stage of partial atrophy and restore vision without allowing complete atrophy.

What are the features of pathology in children

At congenital form disease, you can determine that the baby’s pupils react poorly to light. As the child grows up, parents may notice that he does not respond to an object brought to him from a certain direction.

Important! A child under two or three years old cannot report that he sees poorly, and older children, whose problem is congenital, may not realize that they can see differently. That is why it is necessary for the child to be examined annually by an ophthalmologist, even if there are no symptoms visible to the parent.

Parents should take their child to the doctor if he rubs his eyes or unconsciously tilts his head to one side while trying to look at something. The forced tilt of the head to some extent compensates for the function of the affected nerve and slightly sharpens vision. Main clinical picture with optic nerve atrophy in a child is the same as in an adult.

If diagnosed and treated in a timely manner, provided that the disease is not genetic, during which the nerve fibers are completely replaced fibrous tissue even during intrauterine development, the prognosis for restoration of the optic nerve in children is more favorable than in adult patients.

How is the disease diagnosed?

Diagnosis of optic nerve atrophy is carried out by an ophthalmologist, and first of all includes examination of the fundus and determination of visual fields using computer peripetry. It is also determined which colors the patient can distinguish. Instrumental methods of diagnosis include:

X-ray of the skull;
Magnetic resonance imaging;
angiography of eye vessels;
video-ophthalmological examination;
Ultrasound of the vessels of the head.

Thanks to these studies, it is possible not only to identify the death of the optic nerve, but also to understand why it occurred. You may also need to consult related specialists.

How is optic atrophy treated?

How to treat optic nerve atrophy should be decided by the doctor based on the research conducted. It is immediately worth noting that the treatment of this disease is very difficult, because nerve tissue regenerates very poorly. It is necessary to carry out a comprehensive systematic therapy, which should take into account the cause of the pathology, its duration, the age of the patient, and his general state. If some process occurring inside the skull (for example, a tumor or inflammation) has led to the death of the nerve, then treatment should begin with a neurosurgeon and neuropathologist.

Treatment with medications

By using medicines You can increase blood circulation and nerve trophism, as well as stimulate the vital activity of healthy nerve fibers. Drug treatment includes:

vasodilators - No-Shpy and Dibazol;
vitamin B;
biogenic stimulants, for example, aloe extract;
drugs that improve microcirculation, such as Eufillin and Trental;
steroidal anti-inflammatory drugs - Hydrocortisone and Dexamethasone;
antibacterial drugs, spruce atrophy has an infectious bacterial pathogenesis.

In addition, physical therapy may be required to stimulate the optic nerve, such as laser stimulation, magnetic therapy, or electrophoresis.

Microsurgical treatment is aimed at eliminating compression of the nerve, as well as increasing the diameter of the vessels that feed it. Conditions can also be created in which new blood vessels can grow. Surgery can only help with partial atrophy; if the nerves die completely, then even by surgical intervention it is impossible to restore visual function.

Treatment with folk remedies

Treatment of optic nerve atrophy with folk remedies is permissible only at the initial stage of the disease, but it is not aimed at improving vision, but at eliminating the root cause of the disease.

Important! Self-medication without prior medical consultation can only aggravate the situation and lead to irreversible consequences.

If the disease is caused by high blood pressure, then plants with antihypertensive properties are used in therapy:

Blueberries are beneficial for vision; they contain many vitamins, as well as an anthocyanoside, which has positive influence to the visual apparatus. For treatment you need to mix one kilogram fresh berries with one and a half kilograms of sugar and put in the refrigerator. This mixture is taken in half a glass for a month. The course must be repeated twice a year, which will be beneficial even with good vision.

If degenerative processes occur in the retina of the eye, especially occurring against the background of low blood pressure, then tinctures for the preparation of which are used will be useful:

If incomplete necrosis of the nerves occurs or senile degenerative changes in the eyes, then it is necessary to take anti-sclerotic plants:

Carrots (contain a lot of carotene) and beets (rich in zinc) have beneficial properties.

What is the prognosis for optic nerve atrophy and its prevention?

Upon diagnosis and initiation of therapy early stage development, you can maintain and even slightly increase visual acuity, as well as expand its fields. No treatment can fully restore visual function. If the disease progresses and there is no treatment, it leads to disability due to complete blindness.

In order to prevent the necrosis of nerve fibers, ophthalmological diseases, as well as endocrine, neurological, infectious and rheumatological diseases should be treated in a timely manner. Very important in prevention is the prevention of intoxication damage to the body.

10015 02/21/2019 6 min.

A rapid decrease in vision may indicate various eye diseases. But rarely does anyone think that it can be caused by such dangerous disease as optic nerve atrophy. The optic nerve is an important component in the perception of light information. Therefore, it is worth taking a closer look at this disease so that it is possible to identify the symptoms in the early stages.

What it is?

The optic nerve is a nerve fiber responsible for processing and transmitting light information. The main function of the optic nerve is delivery of nerve impulses to the brain area.

The optic nerve is attached to retinal ganglion neurocytes, which make up the optic disc. Light rays, converted into a nerve impulse, are transmitted along the optic nerve from the retinal cells to the chiasma (the segment where the optic nerves of both eyes intersect).

Where is the optic nerve located?

Its integrity is ensured. However, even the smallest injuries to the optic nerve can lead to severe consequences. The most common disease of the optic nerve is its atrophy.

Optic atrophy is an eye disease in which degradation of the optic nerve occurs, followed by decreased vision. With this disease, the fibers of the optic nerve completely or partially die and are replaced by connective tissue. As a result, light rays falling on the retina of the eye are converted into an electrical signal with distortions, which narrows the field of view and reduces its quality.

Depending on the degree of damage, optic nerve atrophy can be partial or complete. Partial optic nerve atrophy differs from complete atrophy in less pronounced manifestation diseases and maintaining vision at a certain level.

Vision correction traditional methods() for this disease completely ineffective since they are aimed at correcting the refraction of the eye and have nothing to do with the optic nerve.

Causes

Optic nerve atrophy is not an independent disease, but is a consequence of some pathological process in the patient’s body.

Optic atrophy

To the main reasons occurrence of the disease include:

Eye diseases(diseases of the retina, eyeball, eye structures).
Pathologies of the central nervous system(brain damage due to syphilis, brain abscess, skull injury, brain tumors, multiple sclerosis, encephalitis, meningitis, arachnoiditis).
Diseases of cardio-vascular system (cerebral atherosclerosis, arterial hypertension, vasospasm).
Long-term toxic effects of alcohol, nicotine and drugs. Alcohol poisoning methyl alcohol.
Hereditary factor.

Optic nerve atrophy can be congenital or acquired.

Congenital optic atrophy occurs as a result of genetic diseases(in most cases of Leber's disease). In this case, the patient has low quality of vision from birth.

Acquired optic atrophy occurs due to certain diseases at an older age.

Symptoms

Main symptoms partial visual atrophy can be:

Deterioration in the quality of vision and the inability to correct it with traditional methods.
Pain when moving the eyeballs.
Change in color perception.
Narrowing of visual fields (up to the appearance tunnel syndrome, in which the ability to peripherally view is completely lost).
The appearance of blind spots in the field of vision (scotomas).

Stages of optic nerve atrophy

Diagnostics

Typically, diagnosing this disease does not cause any particular difficulties. As a rule, the patient notices a significant decrease in vision and turns to an ophthalmologist, who determines correct diagnosis. Great importance has the identification of the cause of the disease.

To identify optic nerve atrophy in a patient, complex diagnostic methods :

(visual acuity test).
Spheroperimetry(determination of visual fields).
Ophthalmoscopy(detection of pallor of the optic nerve head and narrowing of the fundus vessels).
Tonometry(measurement intraocular pressure).
Videoophthalmography(study of the optic nerve relief).
(examination of areas of the affected nerve).
Computed tomography and nuclear magnetic resonance(brain examination to identify possible reasons, causing optic nerve atrophy).

Except ophthalmological examination the patient may be prescribed an examination by a neurologist or neurosurgeon. This is necessary because the symptoms of optic nerve atrophy may be symptoms of an incipient intracranial pathological process.

Treatment

Treatment of optic nerve atrophy is quite complex. . Destroyed nerve fibers cannot be restored, so first of all it is necessary to stop the process of changes in the tissues of the optic nerve. Because the nerve tissue Since the optic nerve cannot be restored, visual acuity cannot be raised to the previous level. However, the disease must be treated to avoid its progression and blindness. The prognosis of the disease depends on the timing of the start of treatment, so it is advisable to Contact an ophthalmologist immediately.

The difference between partial optic nerve atrophy and complete one is that this form of the disease is treatable and it is still possible to restore vision. The main goal in the treatment of partial optic atrophy is stopping the destruction of optic nerve tissue.

The main efforts should be aimed at eliminating. Treatment of the underlying disease will stop the destruction of optic nerve tissue and restore visual function.

During treatment of the underlying disease that caused optic nerve atrophy, carry out complex therapy. Additionally, during treatment, medications can be used to improve blood supply and nutrition to the optic nerve, improve metabolism, eliminate swelling and inflammation. It would be a good idea to take multivitamins and biostimulants.

As essential medicines use:

Vasodilators. These drugs improve blood circulation and trophism in the tissues of the optic nerve. Among the drugs in this group one can highlight complamin, papaverine, dibazol, no-shpu, halidor, aminophylline, trental, sermion.
Drugs that stimulate the restoration of altered tissues of the optic nerve and improve metabolic processes in him. These include biogenic stimulants(peat, aloe extract), amino acids (glutamic acid), vitamins and immunostimulants (eleuthorococcus, ginseng).
Drugs that dissolve pathological processes and metabolic stimulants(phosphadene, pyrogenal, preductal).

It is necessary to understand that drug therapy does not treat optic nerve atrophy, but only helps to improve the condition of the nerve fibers. To cure optic nerve atrophy, you must first cure the underlying disease.

Physiotherapeutic procedures, which are used in combination with other treatment methods, are also important. Also, methods of magnetic, laser and electrical stimulation of the optic nerve are effective. They contribute to improvement functional state optic nerve and visual functions.

As additional treatment the following apply procedures:

Magnetic stimulation. During this procedure, the optic nerve is exposed to a special device that creates an alternating magnetic field. Magnetic stimulation helps improve blood supply, saturate the tissues of the optic nerve with oxygen, and activate metabolic processes.
. This procedure is carried out using a special electrode, which is inserted behind the eyeball to the optic nerve and apply electrical impulses to it.
Laser stimulation. The essence of this method is non-invasive stimulation of the optic nerve through the cornea or pupil using a special emitter.
Ultrasound therapy. This method effectively stimulates blood circulation and metabolic processes in the tissues of the optic nerve, improves the permeability of the blood-ophthalmic barrier and the sorption properties of eye tissues. If the cause of optic nerve atrophy is encephalitis or tuberculous meningitis, then the disease will be quite difficult to treat with ultrasound.
Electrophoresis. This procedure characterized by the effect of low-power direct current on the eye tissue and medicines. Electrophoresis promotes expansion blood vessels, improving cell metabolism and normalizing metabolism.
Oxygen therapy. This method consists of saturating the tissues of the optic nerve with oxygen, which helps improve metabolic processes in them.

During the treatment of optic nerve atrophy, it is necessary to have a saturated various vitamins And minerals. Need to use more often fresh vegetables and fruits, cereals, meat, dairy products.

It is not recommended to treat the disease with folk remedies, since in this case they are ineffective. If you only hope for folk remedies, you can lose precious time when the quality of vision could still be preserved.

Complications

It must be remembered that optic nerve atrophy is serious illness and you should not treat it yourself. Incorrect self-treatment can lead to sad consequences– complications of the disease.

The most serious complication There may be complete loss of vision. Ignoring treatment leads to further development of the disease and a steady decrease in visual acuity, as a result of which the patient will no longer be able to lead his previous lifestyle. Very often, with optic nerve atrophy, the patient becomes disabled.

Prevention

To avoid the occurrence of optic nerve atrophy, it is necessary to treat diseases in a timely manner, consult an ophthalmologist in a timely manner if visual acuity decreases, and not expose the body to alcohol and drug intoxication. Only if you pay due attention to your health can you reduce the risk of disease.

Video

Partial optic atrophy is a serious disease that is associated with the death of nerve bundles that carry information from the eyes to the brain. We see with brain cells, that special area in the cerebral cortex where the visual image is transmitted directly from the eyes. From these bundles the optic nerve is formed, which is like a cable that connects the eyes with the above-mentioned cells of the visual cortex. Atrophy of part of the bundles that form the optic nerve leads to the fact that part of the visual information is not perceived and the patient sees poorly. The degree of vision loss depends on what part of these nerve bundles has undergone atrophy.

Diagnosis of partial optic nerve atrophy

Today this can be quantified - based on special complex diagnostics, which allows us to understand not only which bundles have atrophied and how many of them, but also to determine the quality of this atrophy and understand the depth of the process.

With complete or almost complete damage to the optic nerve bundles, blindness or poor vision are irreversible, because it is impossible to restore the nerve tissue.
However, in cases where living fibers are present in a certain quantity, we use technologies that can improve the quality of their work, increase conductivity not only through living bundles, but also improve the quality of their functioning, that is, the quality of visual perception.

Treatment of partial optic atrophy

The thesis that partial atrophy of the optic nerve is incurable is not true. In a fairly large number of cases, we manage to improve, and sometimes significantly improve, the visual functions of our patients, providing them best quality life.

We do this therapeutically, based on special techniques, which include methods medicinal effects, physiotherapy, optical influence.
These methods should be used not only in combination, but also take into account the type of atrophy, the depth of the lesion and the quality of conduction of the optic nerves.
Courses of treatment are carried out several times a year until vision improves to the maximum for a particular patient, which has been determined instrumental methods research.

We usually prescribe treatment to patients from the age of three, but some techniques can be used earlier, which we do when early diagnosis.
For adult patients, treatment is also effective in cases of not congenital, but acquired optic nerve atrophy, as a consequence of certain diseases localized in the eyes or along the optic nerve.

Atrophy of any organ is characterized by a decrease in its size and loss of function due to lack of nutrition. Atrophic processes are irreversible and indicate a severe form of any disease. Optic nerve atrophy - complex pathological condition, which is almost untreatable and often ends in vision loss.

Functions of the optic nerve

The optic nerve is white matter large brain, as if brought to the periphery and connected with the brain. This substance conducts visual images from retina, onto which light rays fall, into the cerebral cortex, where the final image is formed, which a person sees. In other words, the optic nerve acts as a supplier of messages to the brain and is the most important component of the entire process of transforming the light information received by the eyes.

Optic atrophy: general description

With atrophy of the optic nerve, its fibers are completely or partially destroyed. They are subsequently replaced by connective tissue. The death of the fibers causes the light signals received by the retina to be converted into electrical signals that are transmitted to the brain. For the brain and eyes, this process is pathological and very dangerous. Against this background, various disorders develop, including decreased visual acuity and narrowing of its fields. Optic nerve atrophy is quite rare in practice, although even the most minor eye injuries can provoke its onset. However, approximately 26% of cases of the disease end with the patient completely losing vision in one eye.

Causes of optic nerve atrophy

Optic nerve atrophy is one of the symptoms of various eye diseases or a stage in the development of any disease. There are many reasons that can lead to this pathology. Among the ophthalmological diseases that can provoke atrophic changes in the optic nerve are the following ailments:

glaucoma;
pigmentary dystrophy retina;
myopia;
uveitis;
retinitis;
optic neuritis,
damage to the central artery of the retina.

Atrophy can also be associated with tumors and diseases of the orbit: optic glioma, neuroma, orbital cancer, meningioma, osteosarcoma and others.

All kinds of diseases of the brain and central nervous system in some cases lead to atrophic processes in the eyes, affecting primarily the optic nerves. Such diseases include:

multiple sclerosis;
pituitary tumors;
meningitis;
brain abscess;
encephalitis;
traumatic brain injuries;
damage to the facial skeleton with injury to the optic nerve.

Types and forms of optic nerve atrophy

This pathological condition can be congenital or acquired. Acquired atrophy is divided into descending and ascending. In the first case, the fibers of the optic nerve are directly affected. In the second, the cells of the retina come under attack.
According to another classification, acquired atrophy can be:

Primary. It is also called a simple form of atrophy, in which the optic disc becomes pale, but has clear boundaries. The vessels in the retina with this type of pathology narrow.
Secondary, which develops due to inflammation of the optic nerve or its stagnation. The boundaries of the disc become unclear.
Glaucomatous, accompanied by increased intraocular pressure.

Based on the extent of damage to the optic nerve fibers, atrophy is divided into partial and complete. The partial (initial) form manifests itself in severe deterioration of vision, which cannot be corrected contact lenses and glasses. At this stage, the remaining visual functions can be preserved, but color perception will be severely impaired. Complete atrophy is damage to the entire optic nerve, in which a person can no longer see anything with the affected eye. Optic nerve atrophy manifests itself in a stationary form (does not develop, but remains at the same level) and progressive. With stationary atrophy, visual functions remain in a stable state. The progressive form is accompanied rapid decline visual acuity. Another classification divides atrophy into unilateral and bilateral, that is, with damage to one or both organs of vision.

Symptoms of optic atrophy

The first and main symptom that manifests itself in any form of optic nerve atrophy is blurred vision. However, it cannot be corrected. This is a sign by which the atrophic process can be distinguished from ametropia - a change in the ability human eye correctly refract light rays. Vision can deteriorate gradually and rapidly. It depends on the form in which atrophic changes occur. In some cases, visual functions decrease within 3-4 months, sometimes a person becomes completely blind in one or both eyes within a few days. In addition to a general decrease in visual acuity, its fields are narrowed.

The patient almost completely loses peripheral vision, which leads to the development of the so-called “tunnel” type of perception of the surrounding reality, when a person sees everything as if through a pipe. In other words, only what is directly in front of the person is visible, and not to the side of him.

Another common symptom optic nerve atrophy - the appearance of scotomas - dark or blind areas that appear in the field of vision. By the location of the scotomas, you can determine which fibers of the nerve or retina are damaged the most. If spots appear right in front of the eyes, then the nerve fibers located closer to the eyes are affected. central department retina or directly in it. Color vision disorder becomes another problem that a person faces with atrophy. Most often, the perception of green and red hues is impaired, rarely - the blue-yellow spectrum.
All these symptoms are signs of the primary form, that is, its initial stage. The patient himself can notice them. Symptoms of secondary atrophy are visible only during examination.

Symptoms of secondary optic atrophy

As soon as a person consults a doctor with symptoms such as decreased visual acuity and narrowing of its fields, the doctor conducts an examination. One of the main methods is ophthalmoscopy - examination of the fundus of the eye using special instruments and devices. During ophthalmoscopy, the following signs of optic nerve atrophy are revealed:

vasoconstriction;
varicose veins;
disc blanching;
decreased pupil reaction to light.

Diagnostics

As already described above, the first method used to identify pathology is ophthalmoscopy. However, symptoms that can be detected by this study, do not allow an accurate diagnosis. Deterioration of vision, lack of pupillary response to light, narrowing of the blood vessels in the eye are signs of many eye diseases, for example, peripheral cataracts. In this regard, many methods are used to diagnose atrophy. various methods:

Also held laboratory research. The patient donates blood and urine for analysis. Tests are prescribed for syphilis, borreliosis and to determine other non-ophthalmological diseases.

How is optic nerve atrophy treated?

It is impossible to restore fibers that have already been destroyed. Treatment helps stop atrophy and save those fibers that are still functioning. There are three ways to combat this pathology:

conservative;
therapeutic;
surgical.

At conservative treatment the patient is prescribed vasoconstrictors and medications whose action is aimed at normalizing the blood supply to the optic nerve. The doctor also prescribes anticoagulants, which inhibit blood clotting activity.

Drugs that stimulate metabolism and medications that relieve inflammation, including hormonal ones, help stop the death of fibers.

Physiotherapeutic treatment involves prescribing:

Surgical method Treatment is focused on removing formations that put pressure on the optic nerve. During the operation, the surgeon can implant biogenic materials into the patient, which will help improve blood circulation in the eye and in the atrophied nerve, in particular. The pathology suffered in most cases leads to the fact that a person is assigned a disability. Patients who are blind or visually impaired are sent for rehabilitation.

Prevention

To prevent optic nerve atrophy, treatment must be started promptly. ophthalmological diseases.

At the first signs of a decrease in visual acuity, you should immediately make an appointment with an ophthalmologist. When atrophy begins, not a minute can be lost. If at the initial stage it is still possible to save most visual functions, then as a result of further atrophic changes a person may become disabled.

Scientists at Harvard Medical School were able to grow a fragment of the optic nerve

An important step towards developing technology to restore vision was taken by American scientists from Harvard Medical School. They were able to grow a fragment of the optic nerve, but have not yet been able to restore vision.

According to research reports published today in the scientific press, experts have found ways to control the mechanism of regeneration of the optic nerve. Moreover, the effectiveness of the methodology is three times higher than similar developments in the field of solving the problem of restoring vision. The experiments were conducted on rats.

One of the reasons that the damaged optic nerve is not capable of self-repair is the presence of a special protein on its surface. This protein is programmed to stop cell growth. As a result, in the history of science there are no examples of normalization of vision due to the regeneration of part of the optic nerve, ITAR-TASS notes. However, experts from Harvard in a series of experiments based on genetic engineering were able to “turn off” a protein that inhibits cell growth. As a result, the affected nerve showed an amazing ability to recover, said the head of the scientific team, Professor Larry Benowitz.

Scientists have not yet managed to “dock” new cells optic nerve with the cells of the pupil so that vision is fully restored. Benowitz believes that the problem now lies in the “precise” alignment of cells at the junction of these two organs. If successful, a new methodology will emerge to restore vision to those with damaged optic nerves, experts say.

Neuroprotection: restoration of the optic nerve has become more realistic

It was a very significant meeting New Year Ophthalmology Times. On the website of this venerable publication, on January 1, 2002, an interview was published with the famous neuro-ophthalmologist, MD, N. Miller (Eye Institute, Johns Hopkins University, Baltimore, USA). The conversation is dedicated current state problems of preventing damage to the optic nerve, as well as topical issues its restoration and regeneration. Significant advances in recent years may surprise specialists and inspire a wide audience. We bring to your attention a summary of the main achievements in this area, worthy of the pen of the best science fiction writers of our time.

Significant progress has been made in the field of prevention of damage to the optic nerve, its restoration and regeneration. It may soon be possible to restore vision to people who have lost it due to optic nerve disease.

In the past, it was believed that the damaged optic nerve could not repair or regenerate due to three main assumptions. First, a mammalian retinal ganglion cell cannot remain viable if its body or axon is damaged. Secondly, if a retinal ganglion cell is affected and its axon is damaged, then a new axon does not develop. Finally, even if a new axon could develop, it would not be able to find " the right way» in the central nervous system(CNS).

Experimental studies in mammals, including humans, have been able to dispel these doubts. Under some conditions, retinal ganglion cells can survive despite disruption due to axonal damage. Retinal ganglion cells with damaged axons can produce new axons. Regenerated axons can reach their true “targets” in the central nervous system. This means that in the future the optic nerve can be protected from damage, regenerated, partially or completely restored.

Apoptosis (genetically programmed cell death) can occur after damage to retinal ganglion cells. Researchers have identified some conditions that initiate this process. Damaged ganglion cells are released into the intercellular space a large number of glutamate is the main excitatory neurotransmitter of the retina.

One way to prevent apoptosis is to reverse the toxic effect of glutamate on retinal ganglion cells. This is being implemented different ways, for example, by administering substances that block the release of glutamate from affected ganglion cells, or by limiting the uptake of glutamate or its interaction with retinal cells. The drug memantine has been shown to provide effective protection retinal ganglion cells after experimental damage to the optic nerve in rats and mice. This has now been proven in humans. More than 1,300 patients with open-angle glaucoma took part in the study, which included 100 centers in 10 countries. When analyzing visual functions, stereo photographs of the fundus, as well as studies of optic nerve fibers, it was found that memantine protects retinal ganglion cells from increased intraocular pressure by affecting glutamate conductivity.

Nitric oxide also poses a threat to retinal ganglion cells. Studies in adult rats and mice have shown that administration of nitric oxide into vitreous led to the death of retinal ganglion cells. When the concentration of nitric oxide was reduced or its production was limited, there was a significant increase in the survival of retinal ganglion cells after experimental damage to the optic nerve. Drugs such as nipradilol and aminoguanidine can reduce nitric oxide and thus protect human ganglion cells from damage. Injections of the drug brimonidine in rats and in tablet form in monkeys also helped preserve optic nerve function in experimental lesions.

The use of growth factors may help protect neurons in both the central nervous system and retinal ganglion cells. Growth factors can also be used to stimulate the regeneration process of optic nerve axons. Dr. Fisher et al showed that mice immunized with myelin protein had a significant increase in the survival of retinal ganglion cells in experimental neuropathy. The mechanisms underlying these phenomena are not yet entirely clear. However, we can already say that in the future it will be possible to prevent the occurrence of optic neuropathies with appropriate vaccines.

Restoration of the optic nerve. Under certain conditions, retinal ganglion cells in adult mammals are capable of self-renewal. Regeneration of the optic nerve is possible if the action of substances that prevent the axon from regenerating is blocked. IN last years A number of studies have been conducted that also indicate the possibility of regeneration of the optic nerve. Dr. Lehman and colleagues showed that the use of the C3 enzyme significantly promoted axonal enlargement in mice in vitro and axon regeneration after experimental lesions in vivo. Dr. Chang and colleagues demonstrated axonal regeneration and restoration of neuronal function in spinal cord and optic nerve in adult mice using growth factors and neurotrophins 3, 4. Another approach was taken by researchers Monsul and Hofman (Johns Hopkins University, USA). They injected cyclic adenosine monophosphate (CAMP) into the vitreous of mice one day after lesioning the optic nerve and found that the axon noticeably regenerated in the area of the lesion. Thus, by changing the internal environment of retinal ganglion cells and their axons, optic nerve regeneration can be stimulated. This means that the damaged optic nerve can be treated not only surgically in combination with the introduction of growth factors or other substances. It is likely that intraocular administration of certain drugs will prove more promising in stimulating regeneration of the affected optic nerve.

The development of new retinal ganglion cell axons does not by itself restore vision. The axons must “pass” through the optic chiasm and synaptic transmissions to the corresponding areas of the brain. The researchers histologically confirmed the possibility correct formation synapses in adult rats.

A promising direction in the field of vision restoration in case of damage to the optic nerve seems to be one that was created on the basis of research on the transplantation of nonspecific cells into the retina of mammals. These cells, in response to damage, can migrate and differentiate, acquiring functions various types nerve cells. They do not have abnormal growth characteristics leading to tumor formation and are not rejected immune system. Thus, nonspecific cells of the retina and ciliary body in embryos and adults of mice and rats, as well as human embryos, can differentiate into retinal ganglion cells. Thus, in the near future, it may be possible to “manufacture” replacement ganglion cells within the eye itself, or to grow these cells externally and transplant them into patients with damaged optic nerves.