How to quickly and easily test binocular vision at home? Normal vision of a healthy person

Binocular vision provides three-dimensional perception of the surrounding world in three-dimensional space. With the help of this visual function, a person can cover with attention not only the objects in front of him, but also those located on the sides. Binocular vision is also called stereoscopic vision. What are the consequences of a violation of stereoscopic perception of the world, and how to improve visual function? Let's look at the questions in the article.

Feature of stereoscopic perception of the world

What is binocular vision? Its function is to provide a monolithic visual picture as a result of combining images of both eyes into a single image. A feature of binocular perception is the formation of a three-dimensional picture of the world with the determination of the location of objects in perspective and the distance between them.

Monocular vision is capable of determining the height and volume of an object, but does not provide an idea of the relative position of objects on a plane. Binocularity is a spatial perception of the world, giving a complete 3D picture of the surrounding reality.

Pay attention! Binocularity improves visual acuity, providing clear perception of visual images.

Three-dimensionality of perception begins to form at the age of two years: the child is able to perceive the world in a three-dimensional image. Immediately after birth, this ability is absent due to inconsistency in the movement of the eyeballs - the eyes “float”. By the age of two months, a baby can already fixate an object with its eyes. At three months, the baby tracks objects in motion located in close proximity to the eyes - hanging bright toys. That is, binocular fixation and fusion reflex are formed.

At six months of age, babies are already able to see objects at different distances. By the age of 12-16 years, the fundus of the eye is completely stabilized, which indicates the completion of the process of formation of binocularity.

Why is binocular vision impaired? For the perfect development of stereoscopic images, certain conditions are necessary:

absence of strabismus;
coordinated work of the eye muscles;
coordinated movements of the eyeballs;
visual acuity from 0.4;
equal visual acuity in both eyes;
proper functioning of the peripheral and central nervous systems;
absence of pathology in the structure of the lens, retina and cornea.

Ditto for normal operation visual centers require symmetry of the location of the eyeballs, absence of pathology optic nerves, the coincidence of the degree of refraction of the corneas of both eyes and the same vision of both eyes. In the absence of these parameters, binocular vision is impaired. Also stereoscopic vision impossible in the absence of one eye.

Pay attention! Stereoscopic vision depends on proper operation visual centers of the brain, which coordinates the fusion reflex of merging two images into one.

Stereoscopic vision impairment

To obtain a clear three-dimensional image, coordinated work of both eyes is required. If the functioning of the eyes is not coordinated, we're talking about about pathology of visual function.

Violation binocular vision may occur for the following reasons:

pathology of muscle coordination—motility disorder;
pathology of the mechanism for synchronizing images into one whole - sensory disorder;
combination of sensory and motor disorder.

Binocular vision is determined using orthoptic devices. The first test is carried out at three years: children are tested for the functioning of the sensory and motor components of visual function. When strabismus is carried out additional test sensory component of binocular vision. An ophthalmologist specializes in problems of stereoscopic vision.

Important! Timely examination of the child by an ophthalmologist prevents the development of strabismus and serious problems with vision for the future.

What causes a violation of stereoscopic vision? These include:

inconsistent eye refraction;
eye muscle defects;
deformation of the cranial bones;
pathological processes of orbital tissue;
brain pathologies;
toxic poisoning;
neoplasms in the brain;
tumors of the visual organs.

The consequence of impaired binocularity is strabismus - the most common pathology visual system.

Strabismus

Strabismus is always a lack of binocular vision, since the visual axes of both eyeballs do not converge. There are several forms of pathology:

valid;
false;
hidden.

With a false form of strabismus, stereoscopic perception of the world is present - this makes it possible to distinguish it from real strabismus. False strabismus does not require treatment.

Heterophoria ( hidden strabismus) is detected following method. If a patient covers one eye with a sheet of paper, it will deviate to the side. If the sheet of paper is removed, the eyeball takes the correct position. This feature is not a defect and does not require treatment.

Impaired visual function with strabismus is expressed in the following symptoms:

bifurcation of the resulting picture of the world;
frequent dizziness with nausea;
tilting the head towards the affected eye muscle;
blocking the mobility of the eye muscle.

The reasons for the development of strabismus are as follows:

hereditary factor;
head injury;
severe infections;
mental disorder;
pathologies of the central nervous system.

Strabismus can be corrected, especially in early age. Various methods are used to treat the disease:

the use of physiotherapy;
therapeutic exercises;
eye lenses and glasses;
laser correction.

With heterophoria it is possible fatigue eyes, double vision. In this case, prismatic glasses are used for constant wearing. In case of severe heterophoria, it is carried out surgical correction, as with obvious strabismus.

At paralytic strabismus First, the cause of the vision defect is removed. Congenital paralytic strabismus in children must be treated as early as possible. Acquired paralytic strabismus is typical for adult patients who have suffered severe infections or illnesses internal organs. Treatment to eliminate the cause of strabismus is usually long-term.

Post-traumatic strabismus is not corrected immediately: 6 months must pass from the moment of injury. In this case, surgical intervention is indicated.

How to diagnose binocular vision

Binocular vision is determined using the following instruments:

autofluorofractometer;
ophthalmoscope;
slit lamp;
monobinoscope.

How to determine binocular vision yourself? Simple techniques have been developed for this. Let's look at them.

Sokolov's technique

Hold a hollow, binocular-like object, such as rolled-up paper, toward one eye. Focus your gaze through the pipe on one distant object. Now bring your palm to your open eye: it is located near the end of the pipe. If binocularity is not balanced, you will find a hole in your palm through which you can view a distant object.

Kalfa technique

Take a pair of markers/pencils: hold one in a horizontal position, the other in a vertical position. Now try to aim and connect the vertical pencil with the horizontal one. If binocularity is not impaired, you can do this without difficulty, because spatial orientation is well developed.

Reading method

Hold a pen or pencil in front of the tip of your nose (2-3 cm) and try to read the printed text. If you can fully comprehend the text with your vision and read, it means that motor and sensory functions are not impaired. A foreign object (a pen in front of your nose) should not interfere with the perception of the text.

Prevention of binocular defects

Binocular vision in adults can be impaired for several reasons. Correction consists of strengthening exercises eye muscles. In this case, the healthy eye is closed, and the patient is loaded.

Exercise

This exercise for developing stereoscopic vision can be performed at home. The algorithm of actions is as follows:

Attach the visual object to the wall.
Move two meters away from the wall.
Extend your arm forward with your index finger raised up.
Shift your focus to the visual object and look at it through the tip of your finger - the tip of your finger should bifurcate.
Shift your focus from your finger to the visual object - now it should split in two.

The purpose of this exercise is to alternately switch the focus of attention from the finger to the object. An important indicator The correct development of stereoscopic vision is the clarity of the perceived image. If the image is blurry, this indicates monocular vision.

Important! Any eye exercises should be discussed in advance with an ophthalmologist.

Prevention of visual impairment in children and adults:

You can’t read books while lying down;
the workplace should be well lit;
Take vitamin C regularly to prevent age-related vision loss;
regularly replenish your body with a complex of essential minerals;
You should regularly relieve the eye muscles from tension - look into the distance, close and open your eyes, rotate your eyeballs.

You should also be regularly examined by an ophthalmologist and adhere to healthy image life, relieve the eyes and not allow them to get tired, perform eye exercises, treat eye diseases in a timely manner.

Bottom line

Binocular vision is the ability to perceive the picture of the world with both eyes, determine the shape and parameters of objects, navigate in space and determine the location of objects relative to each other. Lack of binocularity is always a decrease in the quality of life due to limited perception of the worldview, as well as a health problem. Strabismus is one of the consequences of impaired binocular vision, which can be congenital or acquired. Modern medicine easily copes with the restoration of visual functions. The sooner you start vision correction, the more successful the result will be.

Binocular vision is a method of visual reproduction in which the image from both eyes becomes a single whole. It is this ability that allows us to perceive the world around us voluminous and complete. Thanks to monocular vision, a person can estimate the distance to objects, height, width and other characteristics of objects. But exclusively binocular vision makes it possible to assess the spatial position of objects. It promotes an improved understanding of the world around you. Binocular vision research occurs in many important specialties, such as:

pilot;
astronaut;
autopilot;
surgeon, etc.

The mechanism of binocular vision is the ability to superimpose two pictures into one image. This happens in the cerebral cortex. Two images arriving at both eyes merge there into one stereoscopic one.

In order to end up with a single view, the images formed on the retina must necessarily correspond to each other in shape and size. In this case, they must fall on the corresponding parts of the shell. For any surface point of the retina, there is a corresponding point on the surface of another retina. If the picture hits the disparate points, it causes visual impairment, resulting in double vision.

Only newborns can do without binocular vision. U healthy person The development of this vision starts after a month of life, and allows you to see everything in volume in the future. By the way, it should be noted that newborns have a lack of binocular vision due to weakness of the eye muscles. The result is uncoordinated eye movements that do not provide clear images. However, the restoration of binocular vision occurs quite quickly, and by the first year of life, the child defines the world around him in the same volume as an adult. Full development of vision occurs by the age of 10.

Terms

Adequate binocular vision is observed only in certain conditions. A person must have the following features:

Possibility of fusion.
Synchronous functioning of the motor muscles of the eyes.
Finding the eyes in the same frontal as well as horizontal plane. Due to eye injuries or diseases, visual field misalignment may occur.
Visual acuity is within 0.3-0.4, which is absolutely enough to fully reproduce the image on the retina.
Iseikonia is the same image size on both retinas of the eyes. In some cases, a phenomenon called anisometropia may occur. This is a disorder in which different refraction of the two eyes occurs. The possible range of degree of anisometropia for the presence of binocular vision is 2.0-3.0. This point is taken into account when choosing glasses. If the difference between the corrective lenses is too large, binocular vision becomes impossible.
Transparency of optics. This includes parts of the eye such as the cornea, lens, and vitreous. There should be no pathologies observed in optic nerve, retina. However, it is important that there are no changes in the visual analyzers, namely: the subcortical centers, the optic tract, the chiasm, and the cerebral cortex.

Examination

There are several methods to diagnose binocular vision. Let's look at some of them.

Kalfa method. The study of binocular function is carried out using two thin and long objects (pencils, etc.). The patient holds the object in an outstretched arm, positioning it horizontally, and then tries to touch it with the tip of another object, placed vertically. At in good condition eye task is completed quite easily. However, if binocular vision is impaired, a miss will occur. This can be checked in a simple way: by closing one eye and repeating the task.
Sokolov's method. A tube is applied to one eye, this may be a piece of paper folded accordingly. You need to put your palm on the end of the tube, this is done from the side of the open eye. The result is the appearance of an imaginary hole in the palm, but only if there is adequate binocular vision. That is, there appears to be a hole in the center of the palm.
Reading with a closing subject. A pencil is located a few centimeters from the eyes, covering part of the text. Binocular vision will allow you to read unhindered, even with a pencil. If there are any violations, this will be difficult to do.
Color test. This is the most exact method determination of binocular vision, which uses a special four-point color test. IN this method used images of two green, one red and one white. The patient is wearing glasses with different glasses, one of which is red, the other green. With binocular vision, both colors will be visible, with white appearing red-green. But when different perceptions The white eye will turn the same color as the glass on the dominant eye.

Diagnoses must be made by a specialist

In conclusion, it remains to add that any visual impairment should only be detected by a specialist. Make a diagnosis yourself, even using simple tests, may be dangerous. Therefore, it is best to consult an ophthalmologist for advice and examination. He will do all the necessary manipulations, conduct tests, on the basis of which he will make an accurate conclusion.

Binocular vision allows a person to see with both eyes at the same time. The brain forms the image it sees into a single whole. This fusion of two pictures is scientifically called the fusion reflex. In simple words, binocular vision allows us to see the world as in a 3D image.

In the absence of binocular vision, a person develops strabismus. More details about this unpleasant illness we'll talk in this article. Methods for restoring vision, experiments, prevention, treatment - you will learn all this in this publication.

In order to prevent any deviations in binocular vision from developing, it is necessary to begin correction in a timely manner, because then the prognosis for recovery will be more positive. Do not forget to check with ophthalmologists.

Binocular vision feature

Source: hnb.com.ua

Binocular vision is normal vision in humans. That is, when we look with two eyes, both pictures that appear in the right and left merge into one in our brain. This process is due to the work of special binocular cells.

Discovery of binocular cells!

They were first discovered by the American physiologist Hubel, who later received Nobel Prize for their achievements in the field of scientific research.

If a person has weakened binocular vision, this leads to the development of strabismus. This disease is quite often observed in both children and adults. The main goal of treating this pathology is to restore binocular vision. With strabismus, a person sees with either the right or left eye.

Binocular vision is vision with two eyes with the formation of a single three-dimensional visual image obtained as a result of merging images from both eyes into one.

Only binocular vision allows you to fully perceive the surrounding reality and determine the distances between objects (stereoscopic vision).

Vision with one eye—monocular—gives an idea of the height, width, and shape of an object, but does not allow one to judge the relative position of objects in space. In addition, binocular vision expands the field of view and achieves a clearer perception of visual images, i.e. visual acuity actually improves.

Full binocular vision is prerequisite for a number of professions - drivers, pilots, surgeons, etc.

Binocular vision appears only when images from both eyes merge into one, which gives volume and depth of perception.

Binocular vision develops gradually and reaches full development by 7-15 years. It is possible only due to certain conditions, and a violation of any of them can cause a disorder, as a result of which the nature of vision becomes either monocular (vision with one eye) or simultaneous.

Monocular and simultaneous vision allows you to get an idea only of the height, width and shape of an object without assessing the relative position of objects in space in depth.

Basic qualitative characteristics binocular vision is a deep stereoscopic vision of an object, which allows you to determine its place in space, see in relief, depth and volume. Images of the external world are perceived as three-dimensional.

Visual acuity

With binocular vision, the field of view expands and visual acuity increases (by 0.1-0.2 or more).

During monocular vision, a person adapts and orients himself in space, assessing the size of familiar objects. The further away an object is, the smaller it appears.

When you turn your head, objects located at different distances move relative to each other. Then it is most difficult for vision to navigate among nearby objects, for example, it is difficult to get the end of a thread into the eye of a needle, pour water into a glass, etc.

Source: GlazExpert.ru

The main mechanism of binocular vision is the fusion reflex - the ability to merge in the cortex big brain two images from both retinas into a single stereoscopic picture.

To obtain a single image of an object, it is necessary that the images obtained on the retina correspond to each other in size and shape and fall on identical, so-called corresponding areas of the retina. Each point on the surface of one retina has its own corresponding point in the other retina.

Non-identical points are a set of asymmetrical areas. They are called disparate. If the image of an object falls on the disparate points of the retina, then the image will not merge and double vision will occur.

A newborn does not have coordinated movements of the eyeballs, so there is no binocular vision. At the age of 6-8 weeks, children already have the ability to fix an object with both eyes, and at 3-4 months - stable binocular fixation. By 5-6 months. The fusion reflex is formed directly.

The formation of full-fledged binocular vision ends by the age of 12.

Normal functions better

Normal binocular vision is possible in the presence of certain conditions:

Ability for bifoveal fusion (fusion).
Coordinated work of everyone oculomotor muscles, ensuring a parallel position of the eyeballs when looking into the distance and a corresponding reduction of the visual axes (convergence) when looking close, as well as correct associated movements in the direction of the object in question.
The position of the eyes is in the same frontal and horizontal plane. If one of them is displaced due to injury, inflammatory process in the orbit, the neoplasm disrupts the symmetry of the combination of visual fields.
Visual acuity is at least 0.3-0.4, i.e. sufficient to form a clear image on the retina.
Equal sizes of images on the retina of both eyes - iseikonia. Images of different sizes occur with anisometropia - different refraction of the two eyes. To preserve binocular vision, the permissible degree of anisometropia is up to 2.0-3.0 diopters, this must be taken into account when choosing glasses.
Naturally, the transparency of the optical media (cornea, lens, vitreous body) is necessary, the absence pathological changes in the retina, optic nerve and higher parts of the visual analyzer (chiasma, optic tract, subcortical centers, cerebral cortex)

When looking into the distance, divergence occurs (spreading the visual axes), and when looking close, convergence occurs (bringing the visual axes together). The cerebral cortex suppresses physiological double vision by shifting the gaze to nearby objects and vice versa.

Any disorder of binocular vision leads to concomitant strabismus. By the presence or absence of binocular vision, one can distinguish real strabismus from imaginary, apparent, and from hidden - heterophoria.

Non-instrumental and hardware testing

There are several simple ways determination of binocular vision without the use of instruments.

The first is to press your finger on the eyeball in the eyelid area when the eye is open. In this case, double vision appears if the patient has binocular vision. This is explained by the fact that the displacement of one eye will move the image of the fixed object to asymmetrical points of the retina.

The second method is the pencil experiment, or the so-called slip test, during which the presence or absence of bipocularity is detected using two ordinary pencils. The patient holds one pencil vertically in an outstretched arm, the doctor holds the other in the same position.

The presence of binocular vision in a patient is confirmed if, with a quick movement, he hits the tip of his pencil with the tip of the doctor’s pencil.

The third method is the “hole in the palm” test. With one eye, the patient looks into the distance through a rolled-up paper tube, and in front of the other eye places his palm at the level of the end of the tube. In the presence of binocular vision, images are superimposed, and the patient sees a hole in the palm, and in it there are objects visible with the second eye.

The fourth method is a test with an installation movement. To do this, the patient first fixes his gaze with both eyes on a nearby object, and then covers one eye with his palm, as if “turning off” it from the act of vision.

In most cases, the organ deviates towards the nose or outwards. When the eye is opened, it usually returns to its original position, that is, it makes an adjustment movement. This indicates that the patient has binocular vision.

To more accurately determine the nature of vision in clinical practice Hardware research methods are widely used, in particular the generally accepted Belostotsky-Friedman method using a four-point device “Color test TsT-1.

To determine stereoscopic vision, the “Fly” stereo test (with the image of a fly) from Titmus Optical (USA) is often used. To determine the magnitude of aniseikonia, a phase-separating haploscope is used.

During the study, the patient is asked to combine two semicircles into a complete stepless circle, changing the size of one of the semicircles. The amount of aniseikonia present in the patient is taken as a percentage of the size of the semicircle for the right eye to the size of the semicircle for the left eye.

Hardware methods for studying stereoscopic vision are widely used in pediatric practice to diagnose and treat strabismus.

Sokolov’s experiment with a “hole in the palm” - a tube (for example, a folded piece of paper) is attached to the eye of the subject, through which he looks. He covers his other eye with his palm. In the case of normal binocular vision, the superimposition of images creates the impression of a complete picture through the tube.
Kalf's method, or test with a miss, examines binocular function using two knitting needles (pencils, etc.). The subject holds the knitting needle horizontally with an outstretched arm and tries to hit the tip of the second knitting needle, which is in a vertical position. If you have binocular vision, the task is easily accomplished.
Reading test with a pencil: a pencil is placed at a distance of several centimeters from the reader’s nose, which covers part of the letters. But binocular vision, due to the superimposition of images from two eyes, can be read without changing the position of the head - letters covered with a pencil for one eye are visible to the other and vice versa.

Binocular vision and strabismus

In the presence of strabismus, binocular vision is always absent, since one of the eyes deviates in one direction and the visual axes do not converge on the object in question. One of the main goals of strabismus treatment is to restore binocular vision.

By the presence or absence of binocular vision, one can distinguish real strabismus from imaginary, apparent, and from hidden - heterophoria.

Imaginary strabismus is explained by the fact that the discrepancy between the visual and optical axes reaches a greater value (in some cases 10°), and the centers of the corneas shift to one side or another, creating a false impression of strabismus.

However, imaginary strabismus preserves binocular vision, which makes it possible to establish correct diagnosis. Imaginary strabismus does not need correction.

The hidden is manifested in the deviation of one of the eyes during the period when a person does not fix any object with his gaze and relaxes. Heterophoria is also determined by the installation movement.

If, while the subject is fixating an object, he covers one eye with his palm, then if there is a hidden strabismus, the covered eye will deviate to the side. When the hand is removed, if the patient has binocular vision, the eye makes an adjustment movement.

Source: bolezniglaz.ru

Strabismus is a violation of the position of the eyes, during which deviation of one or both eyes is detected alternately when looking straight. With a symmetrical position of the eyes, images of objects fall on the central areas of each eye.

In the cortical sections of the visual analyzer, they merge into a single binocular image.

With strabismus, fusion does not occur and the central nervous system, to protect against double vision, eliminates the image obtained with a squinting eye. With the long-term existence of this condition, amblyopia develops (a functional, reversible decrease in vision, one of the two eyes is almost not involved in the visual process).

Strabismus is a periodic or constant deviation of one or the other eye from the general direction of fixation. Depending on the type of strabismus, the eye can be directed inward (converging strabismus), outward (divergent strabismus), upward or downward.

Strabismus is not only cosmetic problem, it also interferes with the perception of the spatial environment. If strabismus begins in an adult or in a child in later years, there are usually complaints of double vision.

If strabismus appears early childhood, and only one eye squints, this can cause visual impairment. This is due to the fact that the child’s ONS learns to ignore information sent by the squinting eye, as a result of which the baby cannot “learn” to look with this eye and amblyopia develops.

Source: en.ppt-online.org

Strabismus is considered a childhood disease, since the formation of the binocular apparatus begins in infancy. The eye cannot completely focus its gaze on one object.

Divergence of one of the eyeballs during strabismus leads to a lack of binocular vision

The cause of this pathology may be:

Severe degrees of farsightedness, myopia, myopia or astigmatism that were not corrected on time or the correction of which was carried out incorrectly.
Impacts and head injuries, as well as various diseases brain infectious nature. They have a direct effect on the eye muscles.
Strong mental and physical activity. This is especially true for the central nervous system.
Inflammatory processes or tumors in the muscles of the eye.
Excessive stress on the child's visual organs.
Anomalies, paralysis, heredity and congenital diseases.

The disease is congenital or acquired.

The congenital form of strabismus is caused by hereditary factors leading to the development of pathology in the development of motor muscles of the eye. Possible reasons This form of the disease can be caused by various deviations in the health of the mother during pregnancy, the impact on her body ionizing radiation, alcohol, industrial toxins.

Acquired strabismus occurs by multiple reasons: various injuries, mental disorders, decreased visual acuity of one eye, diseases of the central nervous system, previous infectious diseases.

Symptoms of strabismus

Normal human vision should be binocular. Binocular vision is vision with two eyes connected to visual analyzer(cerebral cortex) images received by each eye into a single image.

Binocular vision enables stereoscopic vision - allows you to see the world around you in three dimensions, determine the distance between objects, perceive depth, and the physicality of the world around you.

With strabismus, this connection does not occur in the visual analyzer and the central nervous system, in order to protect itself from double vision, excludes the image of a squinting eye.

Source: https://o-glazah.ru

Experts distinguish two forms of strabismus: friendly and paralytic.

Concomitant strabismus
With concomitant strabismus, either the left or the right eye squints, the amount of deviation of which from the straight position is approximately the same. Practice shows that strabismus most often occurs in persons with ametropia and anisometropia, among whom farsightedness prevails.

The main cause of concomitant strabismus is most often ametropia, and the more pronounced it is, the greater its role in the occurrence of this pathology.

Experts also include the following reasons for concomitant strabismus:

a state of the visual system when the visual acuity of one eye is significantly lower than the visual acuity of the other;
a disease of the visual system leading to blindness or sharp decline vision;
uncorrected ametropia (hypermetropia, myopia, astigmatism);
violations of the transparency of the refractive media of the eye;
diseases of the retina, optic nerve;
diseases and damage to the central nervous system;
innate differences in anatomical structure both eyes.

Concomitant strabismus is characterized by the following main features:

when fixing a stationary object, one of the eyes is in a state of deviation in any direction (to the nose, to the temple, above, below);
there may be an alternating deviation of one or the other eye;
angle of deviation (primary) (more often or constantly) of the squinting eye when it is included in the act of vision almost always equal to angle abnormalities (secondary) of the fellow eye;
eye mobility (field of vision) is fully preserved in all directions;
there is no double vision;
there is no binocular (volumetric, stereoscopic) vision;
Possible decreased vision in the squinting eye;
ametropia is often detected various types(farsightedness, myopia, astigmatism) and various sizes (aziometropia).

Paralytic strabismus

In paralytic strabismus, one eye squints. The main symptom of this type of strabismus is the restriction or absence of eye movements in the direction of the action of the affected muscle and, as a consequence, impaired binocular vision and double vision.

The causes of this type of strabismus may be due to damage to the corresponding nerves or a violation of the morphology and function of the muscles themselves. These changes can be congenital or occur as a result of infectious diseases, injuries, tumors, or vascular diseases.

Signs of paralytic strabismus:

limitation or lack of eye mobility towards the affected muscle(s);
the primary angle of deviation (deviation) is less than the secondary one;
lack of binocular vision, possibly double vision;
forced deviation of the head towards the changed muscle;
dizziness.

Vary following forms strabismus:

convergent (often combined with farsightedness), when the eye is directed towards the bridge of the nose;
divergent (often combined with myopia), when the eye is directed towards the temple;
vertical (if the eye squints up or down).

With convergent strabismus, the visual axis of one of the eyes is deviated towards the nose. Convergent strabismus usually develops at an early age and is often intermittent at first. More often this type strabismus in the presence of farsightedness of medium and high degrees.

Exotropia!

With divergent strabismus, the visual axis is deviated towards the temple. Divergent strabismus is often congenital or early-onset myopia. The causes of divergent strabismus can be injuries, brain diseases, fear, and infectious diseases.

In addition, there are other combinations of different positions. Strabismus may be permanent or intermittent.

Criteria for the appearance of strabismus

There are several criteria by which strabismus is distinguished.

By time of occurrence:

congenital;
acquired.

Deviation stability:

permanent;
fickle.

By eye involvement:

unilateral (monolateral);
intermittent (alternating).

By origin:

friendly;
paralytic.

By type of deviation:

converging (the eye is directed towards the bridge of the nose);
divergent (the eye is directed towards the temple);
vertical (eye deviation up or down);
mixed.

Prevention of strabismus

The location of the eyeballs should be binocular and binocular vision will be normal. That is, during strabismus it is disrupted single condition for functioning optical system when you can see one common picture with both eyes.

Before making a diagnosis and starting measures that will be aimed at correcting strabismus, a thorough diagnosis of the visual organs is carried out. To avoid worsening the eye condition, treatment should be started as quickly as possible. Therapy is aimed directly at full recovery vision functions.

Experts distinguish two main approaches to treating this problem:

Correction or physical methods.
Surgical intervention.

First, the doctor prescribes glasses or soft contact lenses, which you will have to wear quite for a long time that's all for now obvious symptoms the development of the disease will not subside.

The doctor may also prescribe eye drops and wearing glasses in which the glass of the better seeing organ will be closed, which is done specifically to strengthen the diseased visual organ.

Thanks to modern hardware procedures, the patient’s visual acuity will be restored. Appointed medicines, ointments and injections to relax the eye muscles.

The execution is also specified special complex exercises that are designed to correct and maintain eye muscles. They should be performed repeatedly, the more, the better throughout the day. In some cases, when the problem is not very advanced, this is quite enough.

Diagnostics

To correctly diagnose strabismus, a complete ophthalmological examination. Computer diagnostics is widely used in the examination.

For a complete diagnosis, various tests are carried out for refraction, deviation and motor ability of the eyes, and determine binocular vision. In addition, patients undergo a special neurological examination.

Treatment of strabismus

With strabismus, usually only the eye that performs vision retains the ability to see normally. The one who is deviated to the side sees worse and worse over time, his visual functions are suppressed. Therefore, treatment should begin as early as possible.

Treatment for strabismus may include:

optical correction (glasses, soft contact lenses);
increasing visual acuity in both eyes (treatment of amblyopia) using hardware procedures;
orthoptic and diploptic treatment (development of binocular vision);
consolidation of achieved monocular and binocular functions;
surgical treatment.

Usually the operation is resorted to as cosmetic product, since by itself it rarely restores binocular vision (when the brain combines two images received by the eyes into one).

The type of operation is determined by the surgeon directly on operating table, since during such an operation it is necessary to take into account the peculiarities of the location of the muscles in a particular person.

Surgical treatment to correct strabismus is performed in a “one-day” mode, under local drip anesthesia. The patient returns home on the same day.

Final recovery takes about a week, but after such surgical operation doctors strongly recommend the course hardware treatment For optimal recovery visual functions.

Treatment begins after complete elimination of amblyopia and achievement of a symmetrical or very close to it position of the eyes, with normal correspondence of the retinas. Treatment is carried out comprehensively, including orthoptics, diploptics, effects on the oculomotor system and fusion.

After planar binocular vision has been developed, determined by a color test, stereoptic techniques are included in the treatment complex.

Visual acuity

During one session we use 5 various techniques. The choice of techniques depends on the type of strabismus, ophthalmological status, age of the patient and his intelligence.

With convergent strabismus, an amplipulse is prescribed to the external rectus muscles and the muscle trainer, divergent - an amplipulse to the internal rectus muscles and the convergent trainer, with vertical deviations - an amplipulse to the antagonist muscles; from orthoptic methods - synoptophore is mandatory.

The duration of treatment is 2-3 weeks. After completing treatment in the office, home treatment is required to consolidate the results.

Depending on age and indications, they recommend: gymnastics for horizontal muscles, convergence training, exercises with two pencils, hitting a ring with a pencil, training on a visual field divider, stereoscopes, hitting a ball with a tube, ball games, badminton, and other games and exercises .

It has been noted that binocular and stereoscopic vision is formed faster and easier in children with late development of the disease. With congenital and early-onset strabismus, as already noted, stereoscopic vision cannot be developed.

Diploptics as a type of treatment for strabismus

The therapy in question is considered the final stage in the treatment of strabismus. It is allowed to be performed on patients who have reached the age of two years.

The essence of the method is based on causing double vision of an object, due to which the ability to independently restore binocular vision is developed. In this case, the patient’s strabismus angle should not exceed 7 degrees.

A prismatic glass is placed in front of the eyes, which actually produces double vision. When it is removed, vision is slowly restored. During therapy, the prisms are changed.

The final stage of restoring binocular vision is therapeutic exercises aimed at increasing the mobility of the eyeballs. This is done using the convergence trainer.

How to treat strabismus must be decided by the doctor. In most cases, a few therapeutic procedures are sufficient, but sometimes serious surgery, during which one or both eyes are operated on.

However, strabismus can be treated at home, following all the doctor’s recommendations. Wearing glasses, performing special exercises and procedures - all this allows you to completely restore the balance between your eyes.

In conclusion, I would like to remind you that strabismus does not go away with age, therefore, at the first signs of pathology in yourself or your loved ones, it is necessary to carry out vision correction.

As for the prevention of binocular vision disorders, the following measures must be taken starting from an early age:

When hanging toys above your child's crib, make sure that their location changes several times a week. In addition, place them at least 50 cm from the child’s face and on different sides. The baby's gaze should not focus on one point.
If your child draws and looks at pictures with his head in a book, then you should definitely show him to an ophthalmologist.

Binocular vision is a natural physiological ability that every healthy person possesses. It allows you to look at an object with both eyes and build a single three-dimensional image, which is formed as a result of the merging of pictures from both organs. It is this opportunity that allows a person to experience the depth of perception of the surrounding reality. If there is a violation of this type of vision, it is necessary to begin treatment.

It turns out that it is binocular vision that creates all the conditions so that it is possible to approximately calculate the distance from all kinds of things, objects and objects. Unlike the monocular ability to see (with one eye), binocular vision provides the ability to evaluate the distance and relative position of objects both in the plane and in space.

In addition, it is the review with two eyes that allows you to maximize the field of view and achieve a more accurate acceptance of the visual image. This is felt by a person in the quality of his visual data, their quality and sharpness. Binocular vision (it would be more correct to consider the absence of its impairment) seems to be a mandatory item for a whole list of specialties.

What binocular vision is can be understood by considering the features of its functioning:

The signal sent to the cerebral cortex causes the main element of this visual ability to be triggered, which has a clear definition and name of the fusion reflex.
Merging two images obtained from both retinas into a whole stereoscopic image is necessary to obtain an inseparable, integral image of a specific object.
Extremely an important condition To trigger the fusion reflex, we can call the correspondence of images to each other in size and shape. In addition, they must fall on the same areas of the retina. When merging does not occur due to the fact that the image of the object does not fall on similar areas, what is visible in a person’s eyes splits into two.

As a study by scientists shows, binocular vision is not found in newborns.

The fusion reflex cannot occur, since at this age any healthy baby does not have the slightest coordination of movements between the eyeballs. By 8 weeks, the baby is already able to fixate with his visual organs any object, and by 3-4 months the baby does this much more confidently.

The final stage of formation of this ability in a person is completed by the age of 12. Strabismus, as the most common disorder of binocular vision, is recognized as a disease of preschool children.

Binocular vision status: how to check?

The research carried out by ophthalmologists was not in vain. Today there are several ways to verify the state of your binocular vision.

The most popular and simple techniques are as follows:

Sokolov's method. A tube (or whatever) must be placed to the subject's eye. A person must peer through it into the very distance. The study begins with placing your hand on the other side of the second eye. With normal binocular vision, images overlap and the effect of the presence of a hole in the middle of the palm is created, through which the image is supposedly visible.

Kalfa technique. For the miss test (this is also the name of this method, which determines binocular vision and its level), the use of additional sharp objects (knitting needles, pencils, etc.) will be required. The study is as follows: a person, holding a long stick horizontally in a straight hand, tries to touch it to the end of a second, equally thin object, located vertically. A miss occurs when binocular vision is absent or malfunctions. It is advisable to carry out the experiment with one with an open eye.
Pencil reading test. You should place the pencil on your nose and start reading. The object will interfere and some of the letters will disappear from view. This interferes with normal vision, but by using the binocular way of shifting pictures, you can still read. You just need to tilt your head from one side to the other. Then the letters will become accessible first to one eye, and then to the other. But if this does not happen, there is a violation of binocular visual ability.
The four-point color test is another test that will help check your health. It is based on the principle of a standard division of visual fields related to the right and left eyes. Using multi-colored filters, the binocular perception of the subject is determined.

The most commonly diagnosed pathology of binocular vision can be considered strabismus. When it is present, the visual lines do not “meet” on the object, and one eye deviates in the other direction.

Treatment of strabismus aims to restore binocular visual ability. They can help with this special exercises.

How to learn to see with binocular vision?

To begin treatment and the long process of restoring binocular vision, you should first visit an ophthalmologist. The results of the diagnostics, which must be completed, will predetermine the scheme for further therapy. Surgical treatment is often indicated for patients. Those patients who have been practicing one of the common recovery methods for a long time have a chance of recovery without surgery.

At home, treatment and exercises for the development of binocular vision are easy to carry out.

The first exercises are intended for long-range training of binocular vision. The main object for study is placed on the wall. The distance between him and the patient should be at least 2.5-3 m. Next, clench your fist, and index finger leave, do not clamp and keep straight upright.
Then the hand must be positioned so that it is at a distance of 40 cm from the face. If the end extended finger doubled, but the hand remained one, the result of the exercise is positive - that’s how it should be. Both images must have the same degree of clarity.
If this does not happen, and the second eye sees more blurred, you need to start the exercise over again, now loading the weaker eye.

Other lesson plans are based on the use of colored objects. During the exercise, it is important to learn how to focus your gaze on a complex object. It is necessary to begin treatment by studying its largest details, for example, the contour. It is advisable to study each line in detail, and only then move on to other, smaller fragments. Each time, reducing the chosen target, the exercises help develop focus, moving from large objects to more modest ones.

Binocular vision is the norm for every healthy person. This is the ability to see the world around us with two eyes, forming a single visual image. It gives volume and depth of perception, the ability to navigate in space, distinguish objects, and understand how they are located. Binocular visual function is mandatory for the profession of driver, pilot, and surgeon.

To understand the difference between stereoscopic and binocular vision, you need to know that stereoscopy is one of the qualities of binocular vision, which is responsible for the three-dimensional perception of objects.

A newborn does not have binocular vision because he has floating eyeballs. Patients suffering from diseases of the retina or lens of the eye do not have such vision. In any case, to answer the question of whether a person has the ability to see with both eyes, special testing is carried out.

So, binocular is called vision with both eyes, and monocular - with one. Only the ability to see with two eyes gives a person the opportunity to adequately perceive objects around him using the stereoscopic function. The eyes are a paired organ and their collaboration allows you to evaluate everything that is around in terms of volume, distance, shape, width and height, to distinguish colors and shades.

Monocular vision allows you to perceive the environment only indirectly, without volume, based on the size and shape of objects. A person who sees with one eye will not be able to pour water into a glass or thread a thread into an eye.

Only both types of vision create a complete picture of the visible space and help navigate it.

Mechanism of action

Stereoscopic vision is created using the fusion reflex. It helps to combine two pictures from both retinas into one image by merging them. The retinas of the left and right eyes have identical (corresponding) and asymmetrical (disparate) points. For volumetric vision, it is important that the image falls on identical retinal currents. If the image falls on disparate points of the retina, double vision will occur.

To obtain a single image, several conditions must be met:

the images on the retina must be identical in shape and size;
should fall on the corresponding areas of the retina.

When these conditions are met, a clear image is formed in a person.

Formation of visual ability

From the first day of birth, the movements of the baby's eyeballs are not coordinated, so there is no binocular vision. After six to eight weeks from birth, the child can already focus on an object with both eyes. At three to four months the baby develops a fusion reflex.

A child begins to see fully with both eyes by the age of twelve. It is because of this that strabismus () is typical for children who go to a nursery or kindergarten.

Infographics about the formation of binocular vision in children (from birth to 10 years)

Signs of normal binocular vision

In healthy people it is characterized by a number of signs:

A fully formed fusion reflex, which makes it possible to produce bifoveal fusion (fusion).
The coordinated functioning of the oculomotor muscle tissues, which ensures the parallel position of the eyes when looking at distant objects and the convergence of the visual axes when viewing nearby objects. In addition, it ensures simultaneous eye movement when observing a moving object.
By placing the visual apparatus in the same frontal and horizontal planes. If one eye becomes displaced as a result of injury or inflammation, the symmetry of the fusion of visual fields becomes distorted.
Visual acuity is at least 0.3 – 0.4. Since such indicators are quite enough to form an image with clear outlines on the retina.
Both retinas should have the same image size (iseikonia). With different eye refractions (anisometropia), unequal images appear. To maintain the ability to see with both eyes, the degree of anisometropia should be no more than three diopters. It is important to take this parameter into account when selecting glasses or contact lenses. With a difference between the two lenses of more than 3.0 diopters, even with high visual acuity, a person will not have binocular vision.
The cornea, lens and vitreous body should be completely transparent.

There is no stereoscopic vision with cataracts

Testing binocular and monocular vision

Several methods have been developed to test whether a person has binocular ability:

Sokolov's experience

The Sokolov experiment or “hole in the palm”

This technique has another name – “hole in the palm”.

What to do:

The essence of the technique is that a folded sheet of paper is placed to the patient’s right eye, through which he must examine distant objects. At this time left hand I extend it so that my palm is at a distance of 15 cm from my left eye. That is, a person sees a “palm” and a “tunnel”. If there is binocular vision, then the images overlap each other and it seems as if there is a hole in the palm through which we see the picture.

Another name for the technique is a miss test.

In order to determine the presence of binocular vision using this method, you will need two long objects (for example, 2 pens or 2 pencils). But in principle, you can use your own fingers, although the accuracy will decrease slightly.

Miss test (Kalf method)

What to do:

Take the pencil in one hand and hold it horizontally.
In your other hand, take the second pencil and hold it vertically.
Place them at different distances, move your hands in different sides to confuse yourself, and then try to bring the ends of the pencils together.

If you have stereoscopic vision, then this task is quite simple. Without this ability, you will miss. To verify this, you can repeat the same experiment with closed eye. Since when only one eye is working, 3D perception is disrupted.

"Reading with a Pencil"

You will need: a book and a pencil.

Instructions:

You need to take a book in one hand and a pencil in the other, placing it against the background of the book’s pages.
The pencil should cover some letters.
If binocular ability is present, the patient can read the text even despite the obstacle. This happens by merging the images in the review.

The most accurate study of binocular vision is carried out using a four-point color test. It is based on the fact that visual views can be separated using color filters. To do this you need two objects that are colored in green and one each in red and white. The subject needs to wear glasses, with one red and the other green glass.

If the subject has binocular vision, he will only see red and green colors of objects. A white object will appear red-green because perception occurs with both eyes.
If one eye is dominant, then the white object will take on the color of the lens opposite that eye.
If the patient has simultaneous vision (that is, the visual centers receive impulses from one or the other eye), he will see 5 objects.
If the subject monocular vision, then it will perceive only those objects that are colored the same color as the lens in the seeing eye, without reading a colorless object that will be the same color.

Strabismus

Strabismus (strabismus, heterotropia) is a disease characterized by unformed binocular vision in both eyes. This happens because one eye deviates in one direction or another due to weakness of the muscular system.

Types (classification) of strabismus

Strabismus can cause weakening of one or more extraocular muscles, divided into:

Convergent (esotropia) – with it there will be a deviation eyeball to the bridge of the nose;
Divergent (exotropia) – deviation of the organ of the visual apparatus occurs to the side temporal region heads;
Unilateral - only one eye deviates;
Alternating – alternating deviation of both eyes occurs.

Classification of strabismus according to the form of eye deviation

If a patient has binocular vision, but one or both eyes are deviated from the normal position, this may indicate the presence of false (imaginary or hidden) strabismus (pseudostrabismus).

Imaginary strabismus

It is characterized by a large discrepancy between the visual and optical axes. Also, the centers of the cornea can shift to one side. But treatment in this case is not required.

Hidden strabismus

This type of strabismus can occur periodically when the gaze is not fixed on any object.

This type of pathology is checked as follows:

The patient fixes his gaze on one moving object and covers his eye with his hand. If the eye, which is covered, follows the trajectory of the object, then this indicates hidden strabismus in the patient. This disease does not require treatment.