Optical nerve atrophy or optic neuropathy is a partial or complete cessation of the functioning of the nerve fibers that transmit visual stimulation from the retina to the brain. This leads, as a rule, to a significant decrease or absolute loss of vision, as well as to a narrowing of the visual field, impaired color vision, and blanching of the ONH.
Diagnosis can be made by identifying specific signs of the disease using methods such as ophthalmoscopy, perimetry, color testing, visual acuity, craniography, CT and MRI of the brain, B-scan ultrasound of the eye, retinal angiography, visual EP and others
In case of partial atrophy of the optic nerve, treatment should be aimed at eliminating the cause that caused this complication.
Description of pathology
Disease of the optic nerve in ophthalmology occurs in 1-2% of cases; of them from20 to 25% lead, as a rule, to complete atrophy of the optic nerves and, as a result, to incurable blindness. The pathomorphological change in the presence of this disease is characterized by the destruction of ganglion cells located in the retina with their glial-connective tissue change, obliteration of the capillary network of the nerve, and thinning. The disease can be the result of a large number of other ailments that occur with inflammation, squeezing, swelling, damage to special nerve fibers and disruption of the blood vessels of the eyeball.
Causes of pathology
Factors that lead to optic nerve atrophy (according to ICD-10 code H47.2) - eye diseases, CNS damage, mechanical damage, intoxication, infectious or autoimmune diseases, etc.
The cause of lesions and subsequent atrophic processes in the optic nerves is often some ophthalmic pathological disease: glaucoma, retinal dystrophy, occlusive processes, myopia, uveitis, retinitis, optic neuritis, etc.
The danger of optic nerve atrophy can be directly related to a variety of tumors and diseases of the ocular orbit: meningioma and glioma of the optic nerves, neurinoma, neurofibroma, primary orbital cancer, osteosarcoma, local orbital vasculitis, sarcoidosis, etc.
Among the diseases occurring in the central nervous system, the main role is played by a variety of tumors of the pituitary gland and the cranial fossa, compression of the areas of visual chiasmnerves (chiasm), purulent-inflammatory diseases (abscesses, encephalitis, meningitis), sclerosis, skull injuries and damage to the facial area, which are accompanied by injuries of the optic nerves.
What other causes of optic nerve atrophy are there?
It often happens that the pathology is preceded by the development of hypertension, beriberi, atherosclerosis, as well as prolonged starvation or intoxication of the body (alcohol poisoning, damage by large doses of nicotine, chlorophos, medicinal substances), severe blood loss, for example, with uterine or gastrointestinal diseases, diabetes mellitus, anemia. Can optic nerve atrophy be cured? Let's find out.
Degenerative process that develops in the optic nerve may be due to antiphospholipid syndrome, systemic lupus erythematosus, Wegener's granulomatosis, Takayasu's disease, Horton's disease.
In some cases, this pathology develops as a complication of severe bacterial or viral or parasitic infections.
Congenital atrophy of the optic nerve is observed in acrocephaly (tower-shaped skull), micro- and macrocephaly, craniofacial dysostoses (Cruson's disease), hereditary syndrome. In 30% of all cases of observation, the etiology of this disease remains unclear.
Classification
Atrophy of the optic nerves can be hereditary and non-hereditary (acquired). Hereditary forms of this pathology include autosomal diminant, autosomal recessive and mitochondrial. Autosomal dominant forms can be severe or mild, sometimes the course of the disease is combined with deafness. Autosomal recessive types of atrophy of the optic nerves occur in patients with the syndrome of Vera, Bourneville, Kenny-Coff, Wolfram, Rosenberg-Chattorian, Jensen, and others. The mitochondrial type of pathology is observed with certain mutations in mitochondrial DNA and is accompanied by Leber's disease.
Acquired forms of optic nerve atrophy in children and adults, depending on various factors, can be primary, secondary and glaucomatous.
Primary and secondary forms
The scheme of development of the primary form of atrophy is associated with compression of peripheral neurons in the visual pathway. The ONH does not change, and its boundaries retain their clarity.
In the pathogenesis of secondary forms of nerve atrophy, optic disc swelling is observed, due to pathological processes in the retina, as well as in the optic nerve itself. The replacement of nerve fibers by neuroglia becomes the most pronounced; The optic disc grows in diameter and the process of loss of clarity of boundaries begins. The occurrence of glaucomatous atrophy of the optic nerves can be caused by the collapse of the cribriform plates of the sclera with a regular increase in intraocular pressure.
Color change shape
According to the form of discoloration of the discs of the optic nerves, initial, partial (incomplete) and complete atrophy of the optic nerve is distinguished. The initial degree of pathology can be characterized by slight blanching of the optic disc withpreservation of normal coloration. With a partial form, blanching of the discs in single segments may be observed. Complete atrophy is characterized by uniform blanching and thinning of the entire nerve disk, as well as narrowing of some vessels in the fundus.
Localization
According to localization, there are: ascending (with retinal damage) and descending (with fiber damage) atrophy; according to localization, unilateral and bilateral are also noted; according to the degree of development - stationary and progressive (determined during observation by an ophthalmologist in dynamics).
Symptoms of the pathological process
The main symptom of optic nerve atrophy is visual acuity that cannot be corrected with glasses. With progressive forms of this disease, a decrease in visual function can develop over a period of several weeks to several months, and ends, as a rule, with absolute blindness. In the case of partial atrophy, the pathological change reaches certain limits, after which they do not develop. As a result, vision may only be partially lost.
Narrowing of visual fields
When this pathological process occurs, visual impairment can manifest itself as a concentric narrowing of the visual fields, for example, the disappearance of lateral vision, as well as the development of the so-called "tunnel" vision, a color vision disorder, in particular green-red, less often - blue-yellow parts of the spectrum; the appearance of dark spots in certain areas of the fieldsvision. Typical is the identification of afferent pupillary defects - a decrease in the reactions of the pupils to light, while maintaining a friendly reaction. Similar disturbances of change can be observed both in one and in both pupils.
The main signs of partial optic atrophy can be detected during a routine ophthalmological examination.
Diagnostic methods for determining the disease
When examining patients with such a pathology, it is necessary to find out first of all the presence of independent diseases, the fact of taking medications, as well as contacts with chemicals. The presence of bad habits also plays a role.
During the examination, the ophthalmologist should determine the absence or presence of exophthalmos, examine the mobility of the eyeball, check pupillary reactions to light, as well as corneal reflexes. The quality of vision, perimetry and color perception studies must be carried out.
Ophthalmoscopy
Basic data on the presence, degree and variety of the disease can be obtained using ophthalmoscopy. Depending on the causes and forms of this disease, the ophthalmoscopic picture may vary, however, there are a number of typical characteristics that occur with different types of optic nerve atrophy.
These include:
- Bleaching of the ONH.
- Changing its outline and colors (from gray to yellowish).
- Excavation of disk surfaces.
- Disk reductionnumber of capillaries (Kestenbaum symptom).
- Narrowing of the calibers of the arteries of the retina.
- Venous changes.
Other diagnostic methods
The state of the ONH can be clarified with the help of tomography. Electrophysiological types of studies (VEP) reveal a decrease in lability or an increase in the sensitivity of the optic nerves. In glaucomatous forms of the disease, tonometry can determine changes in intraocular pressure.
Pathologies of the eye sockets are detected using plain radiography. The study of the vessels of the retina is carried out by means of fluorescein angiography. Determination of the characteristics of blood flow in the ophthalmic and supratrochlear arteries, as well as in the intracranial portion of the carotid arteries, is performed using Doppler ultrasound.
If necessary, an eye examination can be supplemented by neurological examinations, which include a consultation with a neurologist, an x-ray of the skull, as well as the Turkish saddle.
Consultation of a neurosurgeon
If a patient is diagnosed with volumetric formations in the brain area or outbreaks of intracranial hypertension, a neurosurgeon should be consulted. In the case of pathogenetic links of this disease with systemic vasculitis, a consultation with a rheumatologist is indicated. In the presence of tumors of the eye orbit, it is necessary to undergo an examination by an ophthalmic oncologist. Therapeutic tactics in the event of occlusive lesions of the arteries is determined by the ophthalmologist surgeon.
In case of atrophy of one or both eyes caused by infectious pathologies, informativelaboratory tests such as ELISA or PCR diagnostics.
Treatment of optic nerve atrophy
Since pathology in most cases cannot be an independent disease, but acts as a consequence of other pathologies, its treatment must begin with the elimination of the factors that caused it. Patients with intracranial tumors, hypertension, arterial aneurysms in the brain are indicated for neurosurgical intervention.
Non-specific methods of conservative treatment of this disease are aimed at the maximum preservation of visual functions. In order to reduce inflammatory infiltration and swelling of the optic nerve, retrobulbar injections of Dexamethasone solution are carried out, as well as intravenous infusions of glucose and calcium chloride solutions and the introduction of diuretic drugs ("Furosemide") intramuscularly.
What else is the treatment for optic atrophy?
Drugs
To normalize blood circulation, pentoxifylline, xanthinol nicotinate, atropine (parabulbarno or retrobulbarno) are indicated; intravenously - nicotinic acid and aminophylline; vitamins (B2, B6, B12), injections with aloe extract; taking medications "Cinnarizine", "Piracetam", "Riboxin", etc. To maintain a normal level of intraocular pressure, it is necessary to carry out instillations of "Pilocarpine", diuretics can also be prescribed.
In cases where there are no contraindications, it can be prescribedacupuncture and physiotherapy, such as electrophoresis, laser or electrical stimulation, magnetotherapy, etc.) If vision drops below 0.01, conservative treatment is not effective.
Do optic nerve atrophy give disability?
Forecast and preventive measures
If this disease of the optic nerves was correctly diagnosed and treated at an early stage, it is possible to preserve vision, however, its complete recovery does not occur. With a progressive form of atrophy of the optic nerve of the eye and the absence of treatment, the development of complete blindness may begin. Disability in this case is issued without fail.
