Complete loss of vision. Blindness: symptoms, types, causes, diagnostic methods Causes of blindness

Blindness implies a severe visual impairment in which a person is unable to see due to pathological changes in the visual apparatus. With this pathological condition, the perception of visual stimuli may be partially reduced or lost completely. Taking into account the nature of origin, congenital and acquired blindness are distinguished. Treatment of the pathology depends on the cause of its occurrence and is selected individually.

Blindness is a whole group of diseases characterized by partial or complete loss of vision or color perception. This pathological condition is a common problem in the modern world, which leads to disability. Congenital vision loss can occur for the following reasons:

• retinopathy of prematurity;
• congenital rubella syndrome;
• albinism;
• hereditary predisposition;
• genetic mutations;
• Bardet-Biedl syndrome;
• taperetinal degenerations;
• aplasia of the eyeball.

Congenital blindness also occurs as a result of infection of the fetus with pathogens such as rubella, tuberculosis or influenza. Children suffering from severe retinol deficiency are at risk. There are 2 types of hereditary blindness: complete and partial.

Acquired blindness most often occurs due to traumatic damage to the visual organs (sometimes to the brain). What diseases lead to complete blindness? In adulthood, vision loss can develop against the background of the following pathological conditions:

• age-related cataract;
• glaucoma;
• retinopathy in diabetes mellitus;
• degeneration of the optic spot;
• optic nerve atrophy;
• onchocerciasis;
• keratomalacia;
• pigmentary rhinitis;
• violation of corneal permeability.

In many cases, pathology in people under 30 years of age is caused by eye injury, which often occurs in industrial conditions. Damage can be not only mechanical, but also chemical. The perception of visual stimuli can also be impaired due to methanol poisoning.

Every year the number of blind people increases. And it has been observed that blindness in one or both eyes most often affects people in developing countries around the world.

Sometimes pathology occurs from smoking, due to damage to the vascular system.

Symptoms

The main manifestation of the disease is the absence of visual sensations. Deterioration of vision can be sudden and complete, or it can be gradual, characterized by the presence of light perception. Sometimes a person with this problem has residual vision (0.01-0.05 diopters) in one eye, which can see with proper glasses correction. If a symptom of a child's blindness is the lack of reaction of the pupil to light, then a complete loss of vision is detected. Sometimes a perceptual (false) form of the disease is diagnosed.

This disease can manifest itself with the following symptoms:

• impaired color perception;
• loss of visual fields;
• decreased visual acuity;
• problems with orientation in space;
• delay in the formation of movements.

Blind people experience significant difficulties with assessing spatial orientation, distinguishing between objects and colors. The quality of life is significantly reduced, difficulties arise with performing usual actions and movements. In case of blindness, the core of the sensory organization of the tactile-kinesthetic-auditory type is formed, the loss of vision is compensated by the strengthening of other senses (hearing, smell, tactile sensations). Congenital blindness in children leads to various complications.

In addition to the above symptoms, children often experience a main speech defect in blindness in the form of tongue-tied speech.

Classification

Taking into account the degree of damage to the visual organs, ophthalmology distinguishes several forms of this disease:

1. Full. Both eyes do not perceive visual stimuli, and the pupils do not react to light. In medical terms, complete loss of vision is called amaurosis.
2. Partial (practical). Residual vision is observed, color perception and light perception are preserved.
3. Subject. The pupils react to changes in the intensity of light pulses, but a person is not able to distinguish the shape of surrounding objects.
4. Hysterical. Develops against the background of mental trauma, due to excessive excitability. No eye changes are observed.
5. Civil. The patient cannot see his fingers at a distance of 3 meters, as a result of which he is unable to move normally and ensure a normal existence for himself. People with this form of pathology need outside help.
6. Professional. Visual impairment interferes with the performance of professional duties.
7. Cortical. The occipital lobes of the cerebral cortex are affected, the reaction to light is preserved.

The following specific types of pathological conditions are also distinguished, accompanied by partial loss of vision:

1. . Visibility in the dark deteriorates significantly; a person cannot see objects and cannot move independently. This form can be congenital or acquired (as a result of certain diseases). In good lighting, people with this diagnosis see very well.
2. Snow blindness. This is the name for temporary blindness from bright light, which occurs as a result of powerful ultraviolet irradiation of the eyes. Temporary blindness from bright light is a consequence of swelling and growth of the cornea. With this disease, complete loss of vision never occurs; short-term blindness in one eye is often observed.
3. Colorblindness. The perception of the color spectrum is impaired; a person is unable to correctly identify colors. Most often, the patient cannot distinguish only some colors; complete color blindness is quite rare. This disease is usually genetic in nature and occurs predominantly in men.

Visual impairment can be permanent or temporary. Sometimes false vision loss occurs. There is such a rare form of vision loss as onchocerciasis (river scotoma), which develops as a result of damage to the visual organs by midges that live in fast-flowing rivers.

In the presence of cognitive impairment, a cognitive form of the disease may develop.

Diagnostics

If visual acuity has decreased significantly, scotomas have appeared, or visual fields have begun to fall out, you should immediately consult a doctor, since such manifestations indicate serious vision problems. It is also necessary to contact an ophthalmologist if damage to the visual organ occurs. To diagnose blindness, the following diagnostic measures are carried out:

• ophthalmoscopy;
• visometry;
• perimetry;
• fluorescein angiography;
• electroretinography;
• campimetry.

Using these studies, the specialist determines the degree of visual impairment. Complete blindness is minus 30 or more. Various blindness tests are performed to detect color vision impairment. To detect the problem in a timely manner and prevent the development of severe complications, it is necessary to contact an ophthalmologist as early as possible. If sudden bursting pain occurs in the eye, scotomas form, an eye burn or penetrating injury occurs, you should immediately call an ambulance.

Timely contact with doctors will help preserve your vision.

Treatment and prognosis

The likelihood of regaining lost vision depends on the cause of blindness. If the pathological condition arose as a result of cataracts, glaucoma, an inflammatory process or an infectious lesion, then to return the perception of visual stimuli it is sufficient to eliminate the primary disease. If surgical intervention is necessary. There is no specific cure for blindness.

Many types of total blindness are reversible. However, visual disturbances caused by optic nerve atrophy or cerebral hemorrhage cannot be treated. Congenital color blindness also cannot be treated. If the pathology cannot be cured conservatively or surgically, then an individual plan is selected aimed at improving the patient’s quality of life. Compensation for blindness and low vision is carried out using the following scientific methods:

1. Guide dogs. Specially trained animals help sick people move around the streets.
2. Computer electronic devices: audiobooks, various manuals in Braille, voice reading programs, models of visual replacement devices, Braille keyboards, and so on.
3. Specialized computer programs for the blind. Modern computer companies have taken care of people with disabilities and created tactile electromechanical panels, Braille and speech input-output, operating systems for the blind Oralux and Adriane Knoppix. A special web technology WAI-ARIA was also created.
4. Bionic eye. The essence of this technology is to implant a retinal prosthesis and integrate a camera into special glasses, which interacts with a video processor and photosensor, sending electrical video signals to the brain.

A guide dog is an excellent assistant for a visually impaired person.

In developed countries, biocells are used in the treatment of blindness. Stem cell treatment is also practiced. The prognosis for the development of amaurosis is in most cases unfavorable. The patient is registered with an ophthalmologist throughout his life. And since such a sudden deterioration in vision (even partial) negatively affects the quality of vision, patients often additionally have to consult a psychiatrist.

Prevention measures

There are no specific preventive measures to prevent the development of blindness. However, it is possible to prevent the development of this pathological condition if you avoid various damage to the visual apparatus and brain, treat existing diseases in a timely manner and regularly visit an ophthalmologist for the purpose of prevention. When the first signs of visual impairment appear, you should immediately consult a doctor.

Every year there are new advances in ophthalmology in the fight against blindness, so in many cases it is possible to restore vision.

Intermittent blindness, otherwise known as temporary loss of vision, affects a person instantly and also disappears instantly.

People share their impressions of how they see like a curtain in front of their eyes that blocks out the light; how individual areas can fall out, forming selective blindness (this occurs during pathological processes in the gray matter of the brain). There is also a loss of orientation in space, the inability to determine the shape or color of an object. Why does this happen and how to deal with temporary blindness?

Features of temporary blindness

Both eyes are not always affected; the situation when only one eye ceases to see is quite common. Loss of vision may appear again, but on a second organ; this often happens in older people with diseases of the cardiovascular system, atherosclerosis and vascular diseases.

Intermittent blindness is sometimes a harbinger of serious diseases such as heart attack or stroke.

Main causes of short-term blindness

Intracranial hypertension (increased pressure in the fluid that surrounds the brain) can cause vision loss.

Thrombosis of the vertebral arteries can also cause vision loss, because these vessels supply blood to the part of the brain that is responsible for vision.

When blood clots enter the eye arteries, they become blocked; the retina of the eye does not receive enough oxygen and nutrients and cannot function normally. As you know, the perception of surrounding objects occurs through the visual analyzer: light, refracted, hits the retina, building an image of what is happening there. This information goes further to the brain. When the retina does not work well enough, it results in loss of vision. After removal or resorption of the blood clot (thrombus), vision is completely restored.

Snow blindness is a phenomenon that occurs from exposure to bright light or looking at sunlit snow-covered expanses. A spasm of the ocular vessels occurs, blood temporarily does not enter the retina, this leads to short-term loss of vision lasting from several seconds to several minutes.

Hysterical loss of vision - people with a tendency to take everything to heart experience temporary blindness under severe stress and psycho-emotional shocks. The sensitivity of the eyelid skin increases, photophobia appears, and can last from several hours to months. Vision loss occurs in one or both eyes.

Migraine blindness is a rare manifestation of the underlying disease, headaches are accompanied by visual disturbances: blurry images, decreased visual acuity, blurred vision and temporary blindness - all these symptoms go side by side with ophthalmic migraine. At the same time, painful sensitivity to loud sounds, nausea, and dizziness increase. Staying still relieves symptoms.

Treatment of blindness

Only a doctor can prescribe complete treatment for you after detailed questioning and collection of symptoms. He will send you to take tests and perform some instrumental manipulations (for example, an electrocardiogram, if there is a suspicion of vascular disease and the risk of heart attack or ischemia).

But you can reduce the risk of repeated episodes of blindness yourself; folk remedies are used for this.

ethnoscience

For any organism, even those who do not suffer from visual impairment, it is useful to eat carrots in any form. But for greater benefit we need “squeeze all the juice out of it” literally: add 3 tablespoons of grated vegetable to a liter of water or milk and cook until tender.

Take a third of a glass of this healing decoction at night.

Drink an infusion of black currant leaves, it will relieve fatigue.

Every day, three times after each meal, half a glass of infusion of lingonberry leaves, lemon balm, raspberry fruits, primrose and snakeweed rhizome, in equal proportions. Two spoons of herbs are poured into 0.7 liters of boiling water and allowed to brew for an hour.

Young nettle soup turns out to have a beneficial effect on vision. Try to cook it more often for one month.

Get fish oil and drink it three times a day.

Diversify your menu with fried or boiled liver.

If snow blindness occurs, isolate your eyes from further exposure to bright light sources; it is better to go to a dark place and lie down, covering your eyes with a bandage.

Eat more sweet peppers, gooseberries, cherries, zucchini, rose hips, peas, green onions, spinach, and beans. As you can see, the list of useful "visual" There are a lot of products, you can easily choose a dish to suit your taste.

Pour 3 tablespoons of rose hips into two glasses of boiling water and cook for 10 minutes. Cool for 8-12 hours and you are ready to use. The recommended dosage is a glass per day, 1/3 after each meal.

Prevention

If one or more cases of vision loss have occurred, you need to follow some simple tips:

Remember, temporary blindness is not an independent disease; it does not always happen from admiring the beauty of snow or the sun’s rays for too long; sometimes it is a harbinger of much more serious illnesses.

Spend a couple of hours on your health, consult a doctor after the incident, it’s better to worry once again and find out that everything is fine than to save a little time and then pay for a long time for the neglected consequences.

Medical term " blindness"(caecitas) is used in cases of complete absence of vision or its significant reduction.

In Statistical Classification of Injuries, Diseases and Causes of Death (Tenth Revision) blindness is defined as less than 3/60, the degree of visual ability, or the degree of narrowing of the visual field to 100. At the same time, with the ability to see in the range from 3/60 to 6/18 or narrowing of the visual field from 100 to 200, it is customary to say about partial vision.

According to WHO, of the 285 million people on the planet who have various visual impairments, 39 million people are affected blindness. 82% of people deprived of the ability to see are in the age group of 50 years and older.

Types of blindness

1. Complete (absolute) blindness. Most often, absolute blindness occurs from birth.
2. Scotoma- partial loss of the visual field. The Greek word skotos translated into Russian means “darkness”.
3. Hemianopsia- loss of certain halves of the visual fields of both visual organs.
4. Daltonism or color, color blindness. Manifests itself in a decrease or absence of the ability of the organ of vision to distinguish shades of colors.

The word "blindness" is used in the popular name of the disease hemeralopia(other name nyctalopia, which means “night blindness” in Greek). Meaning night blindness, in which vision is significantly reduced in low light conditions. The condition when vision deterioration in low light occurs due to the fact that the eyes are tired, for example, after prolonged work with a computer monitor, is usually called “ false night blindness».

When various areas in the visual area of ​​the cerebral cortex are damaged, the so-called selective blindness- lack of ability to see certain specific features, for example, details of the shape of an object, shades of color.

Clinical picture

Light perception and residual vision may remain in one eye (corrected with glasses 0.01-0.05). With a fixed gaze, the angular space visible to the eye does not exceed 10 degrees. To refer to such a vision anomaly, ophthalmologists use the term “ low vision».

Patients with hemianopsia I am concerned about the blindness that occurs from time to time. They complain of a black spot that covers more or less of their field of vision and interferes with their vision. Such people find it difficult to navigate in space, read, or watch TV shows.

At scotoma the ability to see is completely absent or weakened in a small area of ​​​​the space visible to the eye.

At color blindness most often there is a decrease or complete absence of perception of shades of one, two or three primary colors at once: red, green, blue.

So-called cortical blindness characterized by a variety of clinical manifestations. Typically, signs of this type of blindness become more pronounced when under stress or exhaustion. Often, patients with cortical blindness complain of worsening vision towards the end of the day.

Temporary (intermittent) blindness sometimes precedes irreversible loss of vision. “It was as if a curtain had fallen before my eyes,” these are the words used by patients to describe their condition.

Causes of blindness

1. Light rays do not reach or focus on the retina properly.
2. The retina is in a state that does not allow it to perceive light normally.
3. Nerve impulses from the retina enter the centers of the brain in a distorted form.
4. The state of the brain does not allow us to perceive information sent by the organ of vision.

These disorders are the result of various diseases, most often cataracts, which block the flow of light into the visual organ, and glaucoma. According to WHO, due to cataracts, people lose the ability to see in 47.9% of cases. Glaucoma is an asymptomatic disease that ends in an attack and causes blindness in 12.3% of cases. Other common reasons:

Decrease in visual acuity associated with reaching old age (8.7%);
keratitis - an inflammatory process in the cornea, causing it to become cloudy (5.1%);
diabetic retinopathy is a severe complication of diabetes mellitus (4.8%);
trachoma - an infectious eye disease (3.6%);
onchocnerciasis - damage to the eyes and skin by helminths (0.8%).

A number of pregnancy-related factors lead to the development of blindness in children. Thus, retinopathy of prematurity, a serious disease that causes pathological changes in the retina and vitreous body, often leads to irreversible loss of visual functions.

Childhood blindness can develop as a consequence of congenital rubella syndrome. This occurs if the rubella virus is transmitted to the fetus through the mother's blood. Various anomalies occur, including cataracts, heart defects, and congenital deafness. Another type of childhood blindness, xerophthalmia, develops if the cornea does not contain enough vitamin A, which is so necessary for it.

Brief interesting data
For more than 90 years, the white cane has been a symbol, pass and identification of blind people all over the world. For the first time, a blind young photographer from Bristol named James Biggs set out to walk around the city on his own with a white cane. This happened in 1921.
In 2010, inventors from Korea developed a cane for the blind with an ultrasonic sensor. The device notifies the owner about an obstacle in his path using a vibration signal, and about the color of an object - with a voice.

There are genetic causes of blindness and visual impairment. Thus, vision problems are often observed in people with albinism, although complete blindness in albinos is quite rare. A number of mutations associated with various genes lead to the development of Leber congenital amaurosis. This hereditary disease manifests itself at an early age with quite serious visual impairment. Retinal degradation and, as a result, blindness, is one of the manifestations of a rare genetic pathology called Bardet-Biedl syndrome.

It should be noted that the causes of blindness in humans, as well as dogs and cats, are largely similar, but not in cases where blindness in humans develops after taking certain chemicals, such as methanol. Breaking down into formic acid and formaldehyde, this dangerous poison can lead to irreversible loss of vision, many other unpleasant consequences and even death. Just 30 ml of methyl alcohol causes irreversible degradation of the optic nerve.

Diagnostics

All types of scotoma (physiological, pathological, positive, negative, atrial fibrillation) and hemianopsia are detected using perimetry and campimetry - special methods for studying the boundaries and central zone of the visual field.

If a pathology of color perception is suspected, the ophthalmologist uses Rabkin tables. If color vision is impaired, a person cannot recognize certain symbols. To diagnose color blindness, a special device is often used - an anomaloscope.

Treatment

In order for patients with acquired blindness to be able to carry out normal activities with the help of special means, they are asked to change their habits and the daily course of their lives. These patients have access to a variety of manuals, Braille books, reading software, and a variety of simple and complex devices designed to enhance the capabilities of people who are blind or have low vision.

Sudden blindness always becomes a severe mental shock. Along with neurotic reactions to vision loss, the blind often develop anxious depression. Therefore, not only an ophthalmologist, but also a psychiatrist should participate in the treatment process.

As for other forms of blindness, treatment of scotoma and hemianopia is primarily aimed at eliminating the factors that led to loss of areas from the field of vision. For example, if the retina is detached and a tumor is detected, the underlying disease is corrected through surgery. Atrial scotoma, caused by spasm of cerebral vessels, is treated with antispasmodic drugs.

There are currently no treatments for congenital color blindness. At the same time, treatment of acquired pathology can be carried out by eliminating the cause that caused it. In some cases, discontinuation of the drug is sufficient.

New approaches in the treatment of blindness

Thus, in 2009, the world press reported on a successful transplant operation of the so-called bionic eye. As a result of surgery, a completely blind 76-year-old patient partially recovered his vision.

Scientists at Oxford University were able to use stem cells to restore vision to experimental mice that had a complete loss of light sensitivity. This was reported in a university press release in January 2013. At the same time, researchers announced that they intended to continue experiments with stem cells in order to find a way to restore human vision.

In August 2013, the world learned about the achievements of American scientists who were able to decipher the retinal code, previously unknown to science - a unique set of equations that nature uses to convert light into electrical impulses or signals understandable to the brain. The discovery of researchers from New York made it possible to create a prosthesis consisting of a camera and a signal converter from the camera “connected” to the optic nerve.

Prevention

Blindness due to injury can be prevented with eye protection instructions. Nutritional causes of blindness can be eliminated by following simple rules of a balanced diet. Early diagnosis of glaucoma allows for timely treatment of the disease, which helps to avoid blindness that occurs due to this insidious disease. The implementation of public health standards has already had a significant impact in reducing the incidence of loss of vision due to infection.

Controlling your blood sugar and body weight, exercising, quitting smoking, eating foods containing simple carbohydrates, and following a diet can all help prevent vision loss as a result of diabetic retinopathy.

If a person is diagnosed with any disease that can potentially cause blindness, they should regularly visit an ophthalmologist and undergo examinations. It is this measure that will allow the therapeutic effect to be applied even before vision begins to sharply weaken. When independently identifying visual field impairment, it is also important to promptly seek help from doctors.

is a pathological condition in which visual acuity is sharply reduced or completely absent. Depending on the form of the disease, clinical symptoms include decreased visual acuity, the appearance of scotomas, impaired color vision, and loss of the nasal or temporal halves from the visual field. Diagnosis of blindness is based on the results of visometry, perimetry, ophthalmoscopy, fluorescein angiography, electroretinography, campimetry, the Ishihara and FALANT tests, and the Rabkin table. Etiotropic therapy for various forms of blindness differs significantly and is selected for each patient individually.

General information

Causes of blindness

According to WHO statistics, the most common cause of blindness is cataracts (47.9%). Congenital variants of the disease are caused by mutations. As a rule, the reasons for decreased visual acuity in such cases are a familial form of lens opacification, aplasia of the inner lining of the eyeball, taperetinal degenerations, and albinism. A special type of this pathology is cortical blindness, in which clinical manifestations are caused by damage to the occipital lobe of the brain. Common teratogens in relation to the organ of vision are medications, toxins and pathogens of infectious diseases.

There is a high risk of eye damage when the fetus is exposed to teratogenic factors at the stage of embryonic development. In the prenatal period, the development of blindness is provoked by pathogens such as rubella, toxoplasmosis, influenza, and tuberculosis. In adulthood, chlamydial origin of visual impairment due to trachoma is more often observed. Eye damage with frequent loss of vision is typical for helminth infections such as onchocerciasis. Isolated cases of blindness are diagnosed with dirofilariasis.

The etiology of early childhood blindness is associated with exposure to triggers during the birth or perinatal period. In this case, newborns are diagnosed with retinopathy, hypoplasia of the visual pathways or hypoxic damage to the optic nerve, which subsequently lead to visual dysfunction. In children (especially premature ones), a decrease in visual acuity is potentiated by vitamin A deficiency, congenital lens opacity or retinopathy. In young patients, most cases of monocular blindness are caused by traumatic injuries. In old age, decreased vision is associated both with general diseases of the body and with the course of degenerative changes in the retina or optic nerve.

Damage to the inner lining of the eyeball or the optic nerve with a progressive decrease in visual acuity is characteristic of such common diseases as arterial hypertension, atherosclerotic vascular disease, retinopathy due to diabetes mellitus. Blindness can occur secondary to pathologies of the central nervous system - meningitis, encephalitis, toxic brain damage. According to statistics, with timely diagnosis, many cases of this pathology are potentially reversible. As a rule, the cause of irreversible blindness is glaucoma due to the development of optic nerve atrophy.

Symptoms of blindness

Clinically, blindness is classified into amaurosis, scotoma, hemianopia, and color blindness. According to the WHO, a diagnosis of blindness can be made when vision is less than 3/60 or the visual field is narrowed to 10 degrees. If visual acuity is 0, we are talking about absolute blindness. With preserved light perception and response to changes in its intensity, but the inability to distinguish the shape of surrounding objects, blindness is called object blindness. In the civil variant of visual dysfunction, the patient cannot determine the number of fingers on his hand at a distance of 3 meters. There is also occupational blindness, in which visual impairment interferes with the performance of professional duties.

A specific symptom of transient amaurosis is a sudden loss of vision with a total duration of no more than 10 minutes. This phenomenon is associated with reversible ischemic changes in the carotid artery. Leber's amaurosis is manifested by nystagmus and a pronounced decrease in visual acuity, detected in early childhood. Often this form of blindness is combined with keratoconus, cataracts, astigmatism, and strabismus. Extraocular manifestations of pathology include mental retardation, epileptic seizures, hearing loss, hormonal imbalance, and malformations of the kidneys, skeletal system, or central nervous system. Patients with this type of blindness are rarely able to distinguish light from dark or track the movement of nearby objects.

With pathological scotomas, visual field defects are detected, which the patient sees as dark spots before the eyes. These defects can partially obscure the image in question. When scotomas are detected, which the patient does not notice, we are talking about a “negative” version of the pathology caused by damage to the optic nerve fibers. Hemianopsia is binocular blindness affecting one half of the visual field. In the homonymous form of the disease, both right or left halves are lost; in the heteronymous binasal form, the lateral parts are lost; in the heteronymous bitemporal form, the medial parts of the visual field are lost. With color blindness, the ability to differentiate a specific color is impaired. Protanopia is manifested by the inability to perceive red, tritanopia – blue-violet, deuteranopia – green. Achromatopsia is a blindness characterized by pathological color perception, in which patients are unable to distinguish all shades of the color spectrum.

Diagnosis of blindness

Diagnosis of blindness is based on visometry, perimetry, ophthalmoscopy, fluorescein angiography, electroretinography, and campimetry. Visometry allows you to diagnose the degree of visual impairment. Category I includes patients with visual acuity of 0.1-0.3 diopters, category II – 0.05-0.1 diopters, and category III – 0.02-0.05 diopters. In category IV patients, light perception is preserved - 0.02 diopters; in category V patients there is no light perception. In accordance with the results of the examination, patients included in groups I and II are classified as visually impaired. The diagnosis of blindness can only be established for persons of groups III-V. A visual field of 5-10° according to perimetry corresponds to category III, less than 5° – IV.

Also, when performing perimetry, it is possible to identify pathological scotomas, which have the appearance of visual field defects of an oval, round or arcuate shape. Using the campimetry method, the size of the scotoma is measured in the temporal, nasal, frontal and chin points and in 4 oblique meridians, followed by recording the indicators in a special patient chart. The main method for diagnosing hemianopia is perimetry. In the homonymous form of blindness, visual field defects are found in the temporal and nasal regions of different eyes. The binasal variant of the pathology is characterized by loss of the medial, and bitemporal - by the lateral halves of the visual field.

For transient amaurosis, fluorescein angiography is indicated to determine the exact location of the ischemic zone. As a rule, the study reveals embolism of the arteries of the inner lining of the eyeball. Leber amaurosis is characterized by a decrease in the amplitude of waves or their complete absence during electroretinography. During ophthalmoscopy in patients over 8 years of age, calcifications and pigment bodies are detected along the periphery of the fundus. To diagnose color blindness, the Ishihara test, Rabkin’s polychromatic tables, and the FALANT test are used.

Treatment of blindness

In case of transient amaurosis, it is urgently necessary to prescribe vasodilators, direct-acting anticoagulants, thrombolytics, and antiplatelet agents. Specific treatment tactics for Leber blindness have not been developed. Symptomatic therapy includes taking multivitamin complexes and intraorbital injections of vasodilators, and correcting visual acuity with glasses. When diagnosing scotomas, etiotropic treatment is required. If the cause of the disease is retinal detachment, vitrectomy followed by filling or ballooning of the sclera is indicated. When visual field defects appear due to pathological neoplasms, they are removed. In case of blindness caused by spasm of cerebral vessels, it is necessary to prescribe antispasmodics.

Etiotropic therapy of hemianopsia is based on relieving causative factors. Neurosurgical intervention in patients with this form of blindness is indicated for traumatic brain injury, benign or malignant brain tumors. If special treatment methods are not available, a course of rehabilitation is recommended. Specific tactics for the treatment of color blindness have not been developed. To correct visual functions, glasses with special filters or contact lenses are used.

Forecast and prevention of blindness

Specific prevention of blindness has not been developed. With timely diagnosis and treatment, in most cases, visual functions can be preserved. All patients with this pathology must be registered with an ophthalmologist. The prognosis for blindness is often unfavorable. 95% of patients with Leber amaurosis lose their vision irreversibly by age 10 years or earlier. However, with color blindness, visual acuity often does not change. Decreased visual function can cause temporary or permanent loss of performance. If it is impossible to restore the functions of the organ of vision, patients are assigned a disability group. When visual acuity is 0.05-0.2 diopters, it is recommended to study in a special school for visually impaired children, below 0.05 diopters - in educational institutions for the blind.

The extreme severity of visual acuity impairment is called blindness. It develops with abnormalities of the organ of vision and is characterized by a complete or partial inability of the organ of vision to perceive images of objects. Visual perception with blindness becomes either impossible or limited. This is due to a pronounced narrowing of the visual fields with a deterioration in its acuity.

There are the following types of blindness:

• absolute (total);
• practical.

Complete blindness occurs when both eyes do not perceive visual sensations. Practical blindness is characterized by the presence of residual vision, while color perception and the sensation of a light beam are preserved.

Causes of blindness

There are many causes of blindness, but it is absolutely impossible to become blind without a reason. This condition is usually a consequence of the following etiological factors:

• diabetic retinopathy;
• degeneration of the optic spot;
• onchocerciasis;
• xerophthalmia and keratomalacia;
• traumatic damage to the organ of vision.

Several other types of blindness are known:

• , or dichromasia, is a pathology in which the ability to perceive colors or their shades is lost. The disease is genetically determined. It affects mostly men, and women carry the pathological gene. In women, this pathology occurs in 1% of cases, while in men - in 8%. Visual acuity in dichromats does not suffer.
• Some people are unable to distinguish the outlines of objects around them in partial darkness or twilight. In this case, they talk about “night blindness.” It occurs either due to insufficient intake of B vitamins in the body or is genetically predetermined. The vast majority of people suffering from night blindness retain excellent visual acuity in good lighting.
• Snow blindness is manifested by a deterioration or complete absence of visual perception, which is caused by powerful irradiation of the organ of vision with ultraviolet rays. In most cases, such a violation goes away after a certain time, as tissue proliferation occurs. The so-called “snow” vision loss cannot cause absolute blindness. People suffering from this vision anomaly see bright lights, movement of objects and outlines of objects under any circumstances.

Blindness can be temporary or a permanent condition. To determine the degree of visual impairment, visual fields are measured, as well as the acuity of perception in each eye separately. In some cases, for example, after an injury, vision may disappear suddenly, while in other people suffering from certain diseases, a decrease in visual acuity develops gradually until complete blindness occurs. In order to determine the degree of decrease in visual acuity, you should visit an ophthalmologist. The main thing is not to despair, because in many cases, if vision is completely lost, it can be restored. Of course, if a cerebral hemorrhage occurs, then most often there is no need to talk about the return of visual function.

Diagnosis of vision pathology

Blind persons are considered to be those who either have no visual sensations at all, or have only a light sensation, or residual vision of 0.01 D to 0.05 D in the eye with which a person can see with spectacle correction. Blind people are unable to distinguish light, color and shape of objects, their size and location in space. They have serious difficulties in assessing spatial orientation (direction of movement, distance between objects).

This leads to an impoverishment of their sensory experience and makes it difficult to navigate in space, especially when moving from place to place. Their other senses, such as hearing, become more acute, since sounds are a fairly important factor that allows them to navigate the environment more confidently.

Due to blindness, the process of formation of movements is delayed. Many blind people begin to feel negative changes in their volitional and emotional spheres. In the future, most patients manage to overcome these negative phenomena, since other analyzers are involved: skin, auditory, motor. It is they who begin to form the sensory basis with the help of which more complex psychological processes develop: voluntary attention, generalized perception, logical memory and abstract thinking.

Blind people, with the help of these sensitive analyzers, learn to correctly perceive reality. Of course, for their orientation in space and in the formation of imaginative thinking, the leading role is played by visual ideas and life experiences that are preserved in the memory of a suddenly blind person.

Treatment of patients with blindness

Unfortunately, complete blindness, which is caused by damage to the optic nerve or a stroke, has no cure. In such cases, it is not possible to restore vision. In order to improve the quality of life of blind patients, there are special tools that help simplify their daily life: electronic audio books, textbooks in Braille, font software.

For every person, vision loss is a psychological trauma. These people are prone to depression and may have suicidal thoughts. They need moral support and psychological help. In some cases, they may need to consult a psychotherapist.

Modern ophthalmology does not have methods for treating congenital dichromasia, and in the case of an acquired disease, it is necessary to eliminate the causes that led to the loss of color perception. If the cause of the disease is a side effect of pharmacological drugs, then after their withdrawal, color vision is completely restored.

Prevention of blindness

It is possible to prevent the possible development of blindness only if a person has a certain sanitary culture and has access to specialized medical care. In order not to lose vision due to damage to the organ of vision, you should protect it from injury. Proper nutrition can prevent essential blindness. Early diagnosis of intraocular hypertension and pressure correction can avoid the development of blindness due to glaucoma.

Blindness due to diabetic retinopathy can be prevented by correcting blood sugar levels, quitting smoking, and controlling body weight. In case of problems with the health of the organ of vision, you should consult a specialist and not self-medicate. A healthy lifestyle and healthy diet also help prevent blindness.