Atrophy of the optic nerve

Atrophy of the optic nerve is clinically a combination of signs: impairment of visual functions (reduced visual acuity and development of visual field defects) and blurred vision of the optic nerve.

Atrophy of the optic nerve is characterized by a decrease in the diameter of the optic nerve due to a decrease in the number of axons.

[1], [2],

Causes of optic atrophy

Inflammatory processes, degenerative processes, compression, edema, trauma, central nervous system diseases, craniocerebral trauma, common diseases (hypertension, atherosclerosis), intoxications, eyeball diseases, hereditary atrophies and consequent deformities of the skull. In 20% of cases the etiology remains unknown.

Of the diseases of the central nervous system, the causes of optic nerve atrophy can be:

1. tumors of the posterior cranial fossa, pituitary gland, leading to increased intracranial pressure, nipple stasis and atrophy;
2. direct compression of the chiasma;
3. inflammatory diseases of the central nervous system (arachnoiditis, cerebral abscess, multiple sclerosis, meningitis);
4. trauma of the central nervous system, leading to damage to the optic nerve in the orbit, canal, skull cavity in the distant period, in the outcome of basal arachnoiditis, leading to a descending atrophy.

Common causes of optic atrophy:

1. hypertension, leading to a disruption of the hemodynamics of the vessels of the optic nerve as acute and chronic circulatory disorders and to optic atrophy;
2. intoxication (tobacco-alcohol poisoning with methyl alcohol, chlorophos);
3. acute hemorrhage (bleeding).

Diseases of the eyeball that lead to atrophy: damage to retinal ganglion cells (ascending atrophy), acute obstruction of the central artery, dystrophic artery diseases (retinal pigmentary dystrophy), inflammatory diseases of the choroid and retina, glaucoma, uveitis, myopia.

Deformities of the skull (tower skull, Paget's disease, which causes early ossification of the sutures) lead to an increase in intracranial pressure, a stagnant nipple of the optic nerve and atrophy.

When optic nerve atrophy, the nerve fibers, shells, axial cylinders disintegrate and replace them with connective tissue, empty capillaries.

[3], [4]

Symptoms of optic atrophy

1. decreased visual function;
2. changes in the appearance of the optic disc;
3. central vision suffers with the defeat of the maculo-capillary bundle, the formation of a central scotoma;
4. changes in peripheral vision (concentric narrowing, sector-like narrowing), with a focus in chiasm - prolapse of peripheral vision;
5. a change in color perception (at first the perception of green color, then red);
6. Temporal adaptation suffers from damage to peripheral nerve fibers.

Dynamics of visual function during atrophy is not observed.

With partial atrophy, vision is significantly reduced, with complete atrophy comes blindness.

Acquired atrophy of the optic nerve

Acquired atrophy of the optic nerve develops as a result of damage to the optic nerve fibers (descending atrophy) or retinal cells (ascending atrophy).

To the descending atrophy are the processes that damage the fibers of the optic nerve at different levels (orbit, visual canal, skull cavity). The nature of the damage is different: inflammation, trauma, glaucoma, toxic damage, circulatory disturbances in the vessels supplying the optic nerve, metabolic disturbance, compression of visual fibers by volumetric education in the cavity of the orbit or in the cranial cavity, degenerative process, shortsightedness, etc.).

Each etiological factor determines the atrophy of the optic nerve with certain ophthalmoscopic features typical for it, for example, glaucoma, circulatory disturbances in the vessels supplying the optic nerve. Nevertheless, there are characteristics common to atrophy of the optic nerve of any nature: blanching of the optic disc and impairment of visual functions.

The degree of decrease in visual acuity and the nature of visual field defects are determined by the nature of the process that caused atrophy. Visual acuity can range from 0.7 to practical blindness.

According to the ophthalmoscopic picture, primary (simple) atrophy is distinguished, which is characterized by palliation of the optic disc with clear boundaries. On the disk, the number of small vessels (the symptom of Kestenbaum) is reduced. Arteries of the retina are narrowed, veins can be of ordinary caliber or also somewhat narrowed.

Depending on the degree of damage to the visual fibers, and consequently, on the degree of decrease in visual functions and blanching of the optic nerve disk, the initial, or partial, and complete atrophy of the optic nerve is distinguished.

The time during which the blanching of the optic nerve disc develops and its severity depends not only on the nature of the disease that led to optic nerve atrophy, but also from the distance of the lesion focus from the eyeball. So, for example, with inflammatory or traumatic damage to the optic nerve, the first ophthalmoscopic signs of optic nerve atrophy appear after a few days - several weeks from the onset of the disease or the moment of injury. At the same time, under the influence of volumetric education on visual fibers in the cranial cavity, only visual disturbances are clinically manifested at first, and changes on the fundus in the form of optic nerve atrophy develop after many weeks and even months.

[5], [6], [7], [8], [9], [10]

Congenital atrophy of the optic nerve

Congenital, genetically conditioned atrophy of the optic nerve is divided into autosomal dominant, accompanied by an asymmetric decrease in visual acuity from 0.8 to 0.1, and autosomal recessive, characterized by a decrease in visual acuity, often to practical blindness already in early childhood.

In detecting ophthalmoscopic signs of optic nerve atrophy, a thorough clinical examination of the patient, including visual acuity and visual field boundaries on white, red and green colors, and intraocular pressure, should be performed.

In the case of development of atrophy against the background of the edema of the optic disc, even after the disappearance of the edema, the boundaries and the disk pattern remain unclear. Such an ophthalmoscopic picture is called a secondary (postotensive) atrophy of the optic nerve. The arteries of the retina are narrowed in caliber, while the veins are enlarged and convoluted.

When clinical signs of optic nerve atrophy are detected, it is first necessary to establish the cause of the development of this process and the level of damage to visual fibers. To this end, not only a clinical examination, but also CT and / or MRI of the brain and orbitals.

In addition to etiologically conditioned treatment, symptomatic complex therapy is used, including vasodilator therapy, vitamins C and group B, drugs that improve tissue metabolism, various options for stimulating therapy, including electro-, magneto- and laser stimulation of the optic nerve.

Hereditary atrophies occur in six forms:

1. with a recessive type of inheritance (infantile) - from birth to three years there is a complete decrease in vision;
2. with a dominant type (youthful blindness) - from 2-3 to 6-7 years. The course is more benign. Vision is reduced to 0.1-0.2. On the fundus there is a segmental pallor of the optic nerve disc, there may be nystagmus, neurologic symptoms;
3. optic-oto-diabetic syndrome - from 2 to 20 years. Atrophy is combined with retinal pigmentary dystrophy, cataracts, sugar and diabetes insipidus, deafness, urinary tract damage;
4. Behr's syndrome is a complicated atrophy. Bilateral simple atrophy already in the first year of life, falls more aggressively to 0.1-0.05, nystagmus, strabismus, neurological symptoms, defeat of pelvic organs, pyramidal path suffers, mental retardation joins;
5. associated with sex (more often observed in boys, develops in early childhood and slowly increases);
6. Lester's disease (hereditary atrophy of Leicester) - in 90% of cases occurs at the age of 13 to 30 years.

Symptoms. An acute onset, a sharp drop in vision for several hours, less often a few days. Defeat by the type of retrobulbar neuritis. The disc of the optic nerve is not altered at first, then the boundaries appear fading, the small vessels change - microangiopathy. After 3-4 weeks, the optic nerve becomes pale from the temporal side. In 16% of patients, vision improves. Mostly low vision remains for life. Patients are always irritable, nervous, they are concerned about headache, fatigue. The reason is optohiasmatic arachnoiditis.

[11], [12], [13], [14], [15]

Atrophy of the optic nerve in certain diseases

1. Atrophy of the optic nerve is one of the main signs of glaucoma. Glaucomatous atrophy manifests itself pale disk and the formation of a deepening - excavation, which first occupies the central and temporal divisions, and then covers the entire disk. In contrast to the above diseases, leading to disc atrophy, with glaucomatous atrophy the disc is gray, which is associated with the features of the lesion of its glial tissue.
2. Syphilitic atrophy.

Symptoms. The disc of the optic nerve is pale, gray, vessels of normal caliber and sharply narrowed. Peripheral vision narrows in a concentric way, there is no cattle, the color perception suffers early. There may be progressive blindness, which occurs quickly, within a year.

It flows wave-wise: a rapid decrease in vision, then in the period of remission - an improvement, in the period of exacerbation - a repeated deterioration. There is a development of miosis, divergent strabismus, a change in pupils, a lack of reaction to light while preserving convergence and accommodation. The prognosis is poor, blindness occurs within the first three years.

1. Features of atrophy of the optic nerve from the squeezed la (tumor, abscess, cyst, aneurysm, sclerized vessels), which can be in orbit, anterior and posterior cranial fossa. Peripheral vision suffers depending on the localization of the process.
2. Foster - Kennedy syndrome - atherosclerotic atrophy. From the compression can be carotid sclerosis and sclerosis of the eye artery; From softening with sclerosis of arteries, ischemic necrosis occurs. Objectively - excavation, due to the westernization of the trellis plate; benign diffuse atrophy (with sclerosis of small vessels of the pia mater) grows slowly, accompanied by an atherosclerotic change in the vessels of the retina.

Atrophy of the optic nerve in hypertensive disease is the outcome of neuro-retinopathy and diseases of the optic nerve, chiasmas and the visual tract.

Atrophy of the optic nerve with blood loss (gastric, uterine bleeding). After 3-10 days, the picture of neuritis develops. The disc of the optic nerve is pale, the arteries are sharply narrowed, peripheral vision is characterized by concentric constriction and loss of the lower half of the field of vision. The causes are lowering of arterial pressure, anemia, disc alteration.

Atrophy of the optic nerve with intoxication (poisoning with quinine). Characteristic general symptoms of poisoning: nausea, vomiting, hearing loss. On the fundus there is a picture of atrophy. When a male fern is poisoned, vision is reduced, peripheral vision is narrowed, changes occur quickly and are persistent.

[16], [17], [18], [19], [20]

Diagnosis of optic atrophy

The diagnosis is made on the basis of an ophthalmoscopic picture. On examination, blushing of the optic disc is noted; when the maculo-capillary bundle is damaged, the temporal divisions of the optic nerve disk turn pale (retrobulbar neuritis). Blanching of the disc is caused by a decrease in the number of small vessels, proliferation of glia and translucence of the trellis plate. The boundaries of the disc are clear, the caliber and the number of vessels decrease (in norm 10-12, with atrophy 2-3).

Distinguish the acquired and congenital atrophy of the optic nerve.

[21], [22], [23], [24]

Treatment of optic atrophy

In diseases of the central nervous system, a neurologist needs treatment. With other diseases, the following are prescribed:

1. stimulating drugs;
2. vasodilators (papaverine, nospa, compilamine);
3. tissue therapy (vitamins of group B, nicotinic acid intravenously);
4. antisclerotic drugs;
5. anticoagulants (heparin, ATP subcutaneously);
6. ultrasound;
7. acupuncture;
8. enzymes (trypsin, chemotripsin);
9. pyregepal (intramuscularly);
10. Vagosympathetic blockade according to Vishnevsky (0.5% solution of novocaine in the carotid artery region), which leads to vasodilation and a block of sympathetic innervation.