Atrophy of the optic nerve or optical neuropathy - a partial or complete cessation of the functioning of nerve fibers that transmit visual irritation from the retina to the brain. As a rule, this leads to a significant decrease or absolute loss of vision, as well as to a narrowing of the visual field, a violation of color vision, and pallor of the optic disc.
The diagnosis can be made by identifying specific signs of the disease using methods such as ophthalmoscopy, perimetry, color testing, determination of visual acuity, craniography, CT and MRI of the brain, B-scanning ultrasound of the eye, angiography of the retinal vessels, examination of visual VP, etc.
With partial atrophy of the optic nerve, treatment should be aimed at eliminating the cause that caused this complication.
Pathology Description
Optic nerve disease in ophthalmology occurs in 1-2% of cases; from 20 to 25% of them 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 of the eye with their glial-connective tissue change, obliteration of the capillary network of the nerve, as well as thinning. The disease can be the result of a large number of other ailments that occur with inflammation, compression, swelling, damage to special nerve fibers and impaired functioning of the vessels of the eyeball.
Causes of pathology
Factors that lead to the occurrence of optic atrophy (according to ICD-10 code H47.2) are eye diseases, central nervous system damage, mechanical damage, intoxication, infectious or autoimmune diseases, etc.
The cause of lesions and subsequent atrophic processes in the optic nerves is often an ophthalmopathological disease: glaucoma, retinal dystrophy, occlusion processes, myopia, uveitis, retinitis, optic neuritis, etc.
The danger of optic atrophy can be directly associated with a variety of tumors and diseases of the optic orbit: meningioma and glioma of the optic nerves, neurinoma, neurofibroma, primary orbit cancer, osteosarcoma, local orbital vasculitis, sarcoidosis, etc.
Among the diseases that occur in the central nervous system, the main role is played by various tumors of the pituitary gland and cranial fossa, compression of the areas of the optic nerve crosses (chiasm), purulent-inflammatory diseases (abscesses, encephalitis, meningitis), sclerosis, skull injuries and damage to the facial area, which are accompanied by injuries optic nerves.
What other causes of optic atrophy are?
It often happens that pathology is preceded by the development of hypertension, vitamin deficiency, atherosclerosis, as well as prolonged starvation or intoxication of the body (alcohol poisoning, damage to large doses of nicotine, chlorophos, drugs), severe blood loss, for example, with uterine or gastrointestinal diseases, diabetes mellitus, anemia. Can optic atrophy be cured? We find out.
A 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, a similar pathology develops in the form of a complication of severe bacterial or viral or parasitic infections.
Congenital atrophy of the optic nerve is observed with acrocephaly (tower-shaped skull), microcephalus and macrocephaly, craniofacial dysostoses (Cruson's disease), hereditary syndrome. In 30% of all cases of observations, the etiology of this disease remains unclear.
Classification
Atrophy of the optic nerves can be hereditary and non-hereditary (acquired). The hereditary forms of such a pathology include autosomal diminant, autosomal recessive and mitochondrial. Autosomal dominant forms can be difficult or easy, sometimes the course of the disease is combined with deafness. Autosomal recessive types of optic atrophy are found in patients with Vera, Bourneville, Kenny-Koff, Wolfram, Rosenberg-Chattorian, Jensen and others. Mitochondrial types of pathology are observed with certain mutations of mitochondrial DNA and are accompanied by Leber’s disease.
Acquired forms of optic atrophy in children and adults, depending on various factors, can be primary, secondary, and glaucomatous.
Primary and secondary forms
The development pattern of the primary form of atrophy is associated with compression of peripheral neurons in the visual pathway. At the same time, the medical and social disability does not change, and its boundaries remain clear.
In the pathogenesis of secondary forms of nerve atrophy, there is a swelling of the optic nerve disc due to pathological processes in the retina of the eye, as well as in the optic nerve itself. Substitution of nerve fibers with neuroglia becomes most pronounced; DZN increases 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 trellis plates of the sclera with a regular increase in intraocular pressure.
Color Change Form
In the form of discoloration of the optic nerve discs, the initial, partial (incomplete) and complete atrophy of the optic nerve is distinguished. The initial degree of pathology can be characterized by mild blanching of the optic disc with the preservation of the usual color. In partial form, disc blanching in single segments can be observed. Complete atrophy is characterized by uniform blanching and thinning of the entire nerve disc, as well as the narrowing of some vessels in the fundus.
Localization
According to localization: ascending (with damage to the retina) and descending (with damage to the fibers) atrophy; according to localization, one-sided and two-sided are also marked; according to the degree of development - stationary and progressive (determined during the observation by an ophthalmologist in dynamics).
Symptoms of the pathological process
The main sign of optic atrophy is visual acuity that cannot be corrected with glasses. With progressive forms of this disease, a decrease in visual function can develop in the period from several weeks to several months, and usually ends with absolute blindness. In the case of partial atrophy, the pathological change reaches certain limits, after which it does not develop. In this regard, vision can only be partially lost.
Narrowing of the field of view
When this pathological process occurs, visual function impairment can manifest itself in the form of 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, color vision disorder, in particular the green-red, less often the blue-yellow parts of the spectrum ; the appearance of dark spots in certain areas of the visual field. 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 atrophy of the optic nerve can be detected during a routine ophthalmic 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 must determine the absence or presence of exophthalmos, examine the mobility of the eyeball, check the pupils' reactions to light, as well as corneal reflexes. Be sure to check the quality of vision, perimetry and color perception studies.
Ophthalmoscopy
Basic data on the presence, extent and type of 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 atrophy.
These include:
- Blanching of the optic disc.
- Change in its contour and colors (from gray to yellowish).
- Excavation of disk surfaces.
- A decrease in the number of capillaries on the disk (a symptom of Kestenbaum).
- Narrowing the retinal arteries.
- Venous changes.
Other diagnostic methods
The state of the optic disc can be clarified using tomography. Electrophysiological types of studies (VEP) reveal a decrease in lability or an increase in the sensitivity of the optic nerves. With glaucomatous forms of the disease, tonometry can determine the change in intraocular pressure.
Pathologies of the orbits are detected using panoramic radiography. The study of the vessels of the retina is carried out by fluorescence angiography. The determination of blood flow characteristics in the orbital and suprablock arteries, as well as in the intracranial section of the carotid arteries, is carried out by ultrasound dopplerography.
If necessary, eye examination can be supplemented by studies of neurological status, which include a consultation of a neurologist, an x-ray of the skull, as well as the Turkish saddle.
Neurosurgeon consultation
If the patient reveals volumetric formations in the brain region or outbreaks of intracranial hypertension, it is necessary to consult a neurosurgeon. In the case of pathogenetic relationships of this disease with systemic vasculitis, consultation with a rheumatologist is indicated. In the presence of tumors of the eye orbit, it is necessary to undergo an examination by an ophthalmologist. Therapeutic tactics in the event of occlusive lesions of the arteries are determined by the ophthalmologist.
In atrophies of one or both eyes caused by infectious pathologies, laboratory tests such as ELISA or PCR diagnostics are informative.
Treatment of optic atrophy
Since pathology in most cases cannot be an independent disease, but acts as a consequence of other pathologies, its treatment should be started by eliminating the factors that caused it. Neurosurgical intervention is indicated for patients with intracranial tumors, hypertension, and arterial aneurysms in the brain.
Nonspecific methods of conservative treatment of this disease are aimed at the maximum preservation of visual functions. In order to reduce the inflammatory infiltration and swelling of the optic nerve, retrobulbar injections with Dexamethasone solution are carried out, as well as intravenous infusions of glucose and calcium chloride solutions and the administration of diuretics (Furosemide) intramuscularly.
What else is the treatment for optic atrophy?
Preparations
To normalize blood circulation, pentoxifylline, xanthinol nicotinate, atropine (parabulbar or retrobulbar) 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, instillations of Pilocarpine are necessary, and diuretics can also be prescribed.
In cases where there are no contraindications, acupuncture and physiotherapy, for example, electrophoresis, laser or electrical stimulation, magnetotherapy, etc.) can be prescribed. With a decrease in vision below 0.01, conservative treatment is not effective.
Does optic atrophy give a disability?
Forecast and preventive measures
If this disease of the optic nerves was able to be correctly diagnosed and started to be treated at an early stage, preservation of vision is possible, however, its full recovery does not occur. With a progressive form of optic atrophy of the eye and the absence of treatment, the development of complete blindness may begin. Disability in this case is compulsory.