Eye crossing pictures. Adult Strabismus: Causes, Symptoms, and Treatment Options for Crossed Eyes

14.05.202309.06.2023 by alexxlab

What are the main causes of adult strabismus. How does strabismus affect vision in adults. Which treatment options are available for correcting crossed eyes in adults. When should an adult seek medical help for misaligned eyes. Can strabismus be successfully treated later in life.

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Understanding Adult Strabismus: More Than Just Crossed Eyes

Adult strabismus, commonly known as crossed eyes, is a condition where the eyes are misaligned and point in different directions. This misalignment can manifest in various ways, with one eye potentially looking straight ahead while the other turns inward, outward, upward, or downward. The condition can significantly impact vision, as both eyes need to aim at the same spot simultaneously for proper visual processing.

The Mechanics of Eye Movement

To fully grasp the complexity of strabismus, it’s crucial to understand the basic mechanics of eye movement. Six muscles control each eye’s movement:

One muscle moves the eye to the right
One muscle moves the eye to the left
Four muscles control up, down, and diagonal movements

For normal vision to occur, all six muscles must work in perfect harmony. The brain plays a vital role in coordinating these muscles to focus both eyes on a single target.

Causes of Adult Strabismus: Unraveling the Triggers

Adult strabismus can arise from various factors, some of which may be present since childhood, while others can develop later in life. Understanding these causes is crucial for proper diagnosis and treatment.

Health Conditions Associated with Strabismus

Several health problems can contribute to the development of strabismus in adults:

Diabetes
Thyroid disease (particularly Graves’ disease)
Myasthenia gravis
Brain tumors
Stroke

Trauma and Injury

Physical trauma can also lead to strabismus in adults. This includes:

Accidents resulting in head injuries
Damage to eye muscles during eye surgery

Is adult strabismus always a new condition. Not necessarily. Many adults with strabismus have had the condition since childhood, but it can also develop later in life due to various factors.

The Impact of Strabismus on Adult Vision

Strabismus can significantly affect an adult’s vision, leading to various visual disturbances and complications.

Normal Vision vs. Strabismic Vision

In normal vision, both eyes aim at the same spot, allowing the brain to combine the two images into a single, three-dimensional view. This process enables depth perception, crucial for judging distances and spatial relationships.

However, when strabismus is present, the misaligned eye sends a different image to the brain than the properly aligned eye. The brain’s response to this discrepancy can vary depending on when the strabismus developed.

Childhood vs. Adult-Onset Strabismus

When strabismus develops in childhood, the brain often adapts by ignoring the image from the misaligned eye, focusing solely on the image from the straight or better-seeing eye. This adaptation, while preventing double vision, results in a loss of depth perception.

In contrast, adults who develop strabismus later in life often experience double vision. This occurs because their brains have already learned to receive and process images from both eyes and cannot ignore the conflicting input from the misaligned eye.

Recognizing the Symptoms of Adult Strabismus

Identifying the symptoms of adult strabismus is crucial for early diagnosis and treatment. While the most obvious sign is visibly misaligned eyes, there are several other symptoms to be aware of:

Eye weakness: Feeling of weakness in or around the eye, or a sensation of something pulling around the eyes
Vision changes: These can include double vision, blurred vision, difficulty reading, or loss of depth perception
Head positioning: Constantly tilting or turning the head to see an image clearly

It’s important to note that these symptoms can be constant or intermittent, varying in intensity and frequency.

When to Seek Medical Attention

Should an adult seek immediate medical attention for sudden eye misalignment. Yes, sudden onset of strabismus in adults can be a sign of a serious underlying condition, such as a stroke or brain tumor. It’s crucial to consult an ophthalmologist promptly if you experience sudden eye misalignment or any of the symptoms mentioned above.

Comprehensive Treatment Options for Adult Strabismus

Treating adult strabismus involves a range of options, from non-invasive techniques to surgical interventions. The choice of treatment depends on the underlying cause, severity of the condition, and individual patient factors.

Surgical Intervention: Realigning the Eyes

Strabismus surgery is the most common and often most effective treatment for adult strabismus. This procedure aims to improve eye alignment and restore proper vision.

How does strabismus surgery work. The surgery involves adjusting the tension of the eye muscles. An ophthalmologist may loosen, tighten, or reposition certain eye muscles to help the eyes line up correctly and work together. This is typically done as an outpatient procedure under general or local anesthesia.

Key points about strabismus surgery:

It may be performed on one or both eyes
Multiple surgeries might be necessary for optimal results
Recovery time is relatively short, with most patients returning to daily activities within a few days

Non-Surgical Treatment Options

While surgery is often the most effective treatment, there are several non-surgical options that can help manage adult strabismus:

Eye muscle exercises: These can be particularly helpful for convergence insufficiency, a condition where the eyes don’t align properly for close-up tasks.
Prism eyeglasses: These special lenses can help correct mild double vision by bending light rays to allow proper image alignment.
Botulinum toxin (BotoxÂ®) injections: In some cases, Botox injections into the eye muscles can temporarily paralyze overactive muscles, potentially improving alignment.

The Importance of Timely Treatment for Adult Strabismus

A common misconception is that strabismus can only be effectively treated in childhood. However, this is far from the truth.

Can adult strabismus be successfully treated. Absolutely. It’s never too late to seek treatment for strabismus. Adults can benefit significantly from various treatment options, experiencing improved eye alignment, better vision, and enhanced quality of life.

Benefits of Treating Adult Strabismus

Addressing strabismus in adulthood can lead to numerous benefits:

Improved visual function and depth perception
Elimination or reduction of double vision
Enhanced peripheral vision
Improved physical appearance and self-esteem
Potential career benefits, especially in fields requiring excellent visual skills

Is there a cut-off age for strabismus treatment. No, there isn’t a specific age limit for treating strabismus. Even elderly patients can benefit from treatment, although individual factors such as overall health and specific eye conditions will influence the treatment approach.

Living with Strabismus: Coping Strategies and Support

While seeking medical treatment is crucial, there are also several strategies that can help adults cope with strabismus in their daily lives:

Adaptive Techniques

Head positioning: Temporarily tilting or turning the head can help align images in cases of mild strabismus
Visual aids: Using magnifiers or adjusting lighting can assist with reading and close-up tasks
Workplace modifications: Ergonomic adjustments to computer screens or workstations can reduce eye strain

Emotional and Social Support

Living with strabismus can have psychological impacts. It’s important to address these aspects:

Seek support groups or counseling to address self-esteem issues
Educate friends, family, and colleagues about the condition to foster understanding
Focus on overall eye health through regular check-ups and a healthy lifestyle

How can one build confidence while living with strabismus. Building confidence involves a combination of self-acceptance, seeking appropriate treatment, and focusing on one’s strengths and abilities beyond physical appearance. Remember, strabismus doesn’t define a person’s worth or capabilities.

Advances in Strabismus Research and Future Treatments

The field of strabismus treatment is continually evolving, with researchers exploring new techniques and technologies to improve outcomes for patients.

Emerging Technologies

Several promising areas of research are shaping the future of strabismus treatment:

Gene therapy: Targeting specific genes involved in eye muscle function
Stem cell treatments: Potential regeneration of damaged eye muscles or nerves
Advanced imaging techniques: Improved diagnosis and treatment planning
Robotics-assisted surgery: Enhancing precision in strabismus surgeries

Personalized Treatment Approaches

The future of strabismus treatment is likely to become increasingly personalized, taking into account individual genetic factors, lifestyle considerations, and specific visual needs.

What role might artificial intelligence play in strabismus treatment. AI could potentially revolutionize strabismus care by improving diagnostic accuracy, predicting treatment outcomes, and assisting in surgical planning. However, these applications are still in the research and development phase.

As research progresses, adults with strabismus can look forward to more effective, less invasive, and more personalized treatment options in the coming years.

Preventing Complications of Adult Strabismus

While not all cases of adult strabismus can be prevented, there are steps that can be taken to reduce the risk of complications or worsening of the condition:

Regular Eye Examinations

Routine eye check-ups are crucial for early detection and management of strabismus and other eye conditions. Adults should have comprehensive eye exams at least every two years, or more frequently if recommended by their eye care professional.

Managing Underlying Health Conditions

Since certain health issues can contribute to strabismus, proper management of these conditions is essential:

Control blood sugar levels if diabetic
Follow treatment plans for thyroid disorders
Manage neurological conditions under medical supervision

Protecting Eyes from Injury

Taking precautions to prevent eye injuries can help reduce the risk of strabismus:

Wear protective eyewear during sports or hazardous activities
Use proper eye protection in work environments with potential eye hazards
Practice good eye hygiene and avoid rubbing eyes excessively

Can lifestyle changes help prevent or manage adult strabismus. While lifestyle changes alone may not prevent strabismus, maintaining overall eye health through a balanced diet, regular exercise, and avoiding smoking can contribute to better eye function and potentially reduce the risk of certain types of strabismus.

The Role of Vision Therapy in Adult Strabismus Management

Vision therapy, a form of physical therapy for the eyes and brain, can play a significant role in managing certain types of adult strabismus, particularly when used in conjunction with other treatments.

What is Vision Therapy?

Vision therapy involves a series of eye exercises and activities designed to improve visual function and eye coordination. It aims to retrain the brain’s connection with the eyes, potentially improving eye alignment and visual processing.

Benefits of Vision Therapy for Strabismus

Vision therapy can offer several benefits for adults with strabismus:

Improved eye teaming and coordination
Enhanced depth perception
Reduced eye strain and fatigue
Improved visual comfort for near tasks like reading or computer work

Is vision therapy suitable for all types of adult strabismus. While vision therapy can be beneficial in many cases, it’s not universally effective for all types of strabismus. Its suitability depends on the specific cause and nature of the misalignment. An experienced eye care professional can determine if vision therapy is appropriate for an individual case.

The Vision Therapy Process

A typical vision therapy program for adult strabismus might include:

Comprehensive eye examination and assessment
Customized therapy plan based on individual needs
Regular in-office sessions with a trained therapist
Home exercises to reinforce progress
Periodic evaluations to track improvement and adjust the treatment plan

Vision therapy is often used in combination with other treatments, such as corrective lenses or surgery, to achieve optimal results in managing adult strabismus.

What Is Adult Strabismus? – American Academy of Ophthalmology

Adult strabismus (crossed eyes) is when your eyes are not lined up properly and they point in different directions. One eye may look straight ahead while the other eye turns in, out, up, or down. The misalignment can shift from one eye to the other.

Strabismus affects vision, since both eyes must aim at the same spot together to see properly.

There Are Six Eye Muscles That Control Eye Movement

One muscle moves the eye to the right, and one muscle moves the eye to the left. The other four muscles move the eye up, down, and at an angle. In order to focus on a single image, all six eye muscles must work together.

What Causes Adult Strabismus (Crossed Eyes)?

To line up and focus both eyes on a single target, all muscles in both eyes must be balanced and working together. The brain controls these muscles. People who have strabismus usually have a problem that can affect eye muscles. Some of those problems may include:

Health problems such as diabetes, thyroid disease (Graves’ disease), Myasthenia gravis, brain tumors, or a stroke

Accidents or head injury

Damage to eye muscles during some kind of eye surgery

Most adults with strabismus have had it since they were children. But sometimes it starts later in life.

How Does Adult Strabismus Affect Vision?

With normal vision, both eyes aim at the same spot. The brain combines the two images from our eyes into a single, three-dimensional (3-D) image. This is how we can tell how near or far something is from us (called depth perception).

When one eye is out of alignment, two different pictures are sent to the brain. In a young child, the brain learns to ignore the image of the misaligned eye. Instead, it sees only the image from the straight or better-seeing eye. As a result, the child loses depth perception.

Adults who develop strabismus after childhood often have double vision. This is because their brains have already learned to receive images from both eyes. Their brains cannot ignore the image from the turned eye, so they see two images.

What Are the Symptoms of Adult Strabismus (Crossed Eyes)?

The most obvious symptom is having eyes that appear out of alignment. Adults with strabismus also may notice these other symptoms:

Weakness in or around the eye, or feeling like something is pulling around your eyes.

Vision changes, such as double vision (seeing two of one image), blurry vision, trouble reading, or a loss of depth perception.

Constantly tilting or turning your head to see an image clearly.

Strabismus symptoms can be constant, or they can come and go.

Adult Strabismus (Crossed Eyes) Treatment

There are several ways to treat strabismus in adults.

Adult strabismus (crossed eyes) surgery

This is the most common treatment for strabismus. Surgery can improve eye alignment and help restore proper vision.

Typically, strabismus occurs when the muscles around the eyes are either too stiff or too weak. An ophthalmologist can loosen, tighten, or move certain eye muscles so that the eyes line up properly to work together. More than one surgery may be needed to treat strabismus.

Surgery is usually done as outpatient surgery in a hospital or surgery center, using either general or local anesthesia. Your ophthalmologist makes a small cut in the tissue covering the eye to reach the eye muscles. The muscles are then repositioned to help the eyes point in the same direction. This may need to be done in one or both eyes. After strabismus surgery, you can get back to your daily routine within a few days.

Eye muscle exercises

An ophthalmologist can teach you exercises to help you focus both eyes inward. These exercises can help if you have “convergence insufficiency.” That is when your eyes do not align properly for close tasks, like reading or computer work.

Prism eyeglasses

A prism is a clear, wedge-shaped lens that bends (refracts) light rays. A prism can be attached to eyeglasses or made as part of the lens. Prisms can help some people with mild double vision see one image, not two.

Botulinum toxin (Botox®)

In some cases, an injection (shot) of this drug in the eye muscles can help treat strabismus. It paralyzes the muscles that keep your eyes from aligning properly. The effect can last for just a few months, or it could permanently improve eye alignment.

It Is Never Too Late to Treat Strabismus

You do not have to live with the discomfort and problems caused by misaligned eyes. With your ophthalmologist’s help, you can find a treatment for your strabismus.

crosseyed photos on Flickr | Flickr

Eye Refractometry | Refractometry interpretation

Visual acuity and other important features of vision depend on how the optical system of the eyeball refracts and then focuses light rays. Refractometry is a fast, accurate, informative and safe method of diagnostic examination. The method allows, even at an early stage, to detect astigmatism, myopia, hyperopia or other ophthalmic pathology, determine the severity of the anomaly and predict the rate of development of the disease.

Without a correct assessment of the refraction of the eye, it is impossible to establish an accurate diagnosis, obtain the necessary personal recommendations from an ophthalmologist, correct the disorder and improve the quality of life of a child or an adult.

What the refraction of the eye says

Light rays pass through several refractive structures: the cornea, aqueous humor of the anterior and posterior chambers of the eye, the lens and the vitreous body. After that, they fall on the retina.

In turn, the light-sensitive tissue transforms the rays into nerve impulses. Through the optic nerve, electrical signals enter the brain and form a picture in the departments that process visual information.

Clinical refraction – the focus of the intersection of light rays relative to the retina. If it is located:

directly on the light-sensitive tissue, ophthalmologists speak of 100% vision;
in front of her, doctors diagnose myopia;
behind the retina, reveal farsightedness;
in the case of astigmatism, the light beam after refraction is focused not at one point, but at several at once.

Any pathology of refraction negatively affects visual acuity, causes discomfort to a person, complicates the learning process, interferes with work activities and causes inconvenience in everyday life.

Reasons for the examination

The procedure is used to diagnose visual impairment, to clarify the medical opinion and the degree of the identified anomaly. In addition, it is part of a comprehensive assessment of the health of the optical system.

Eye refractometry is indicated:

in case of sharp or gradual deterioration of vision;
in case of change in vision of nearby objects or objects far away;
after laser vision correction, surgical intervention in the optical system;
before surgical treatment.

Examination is required for any distortion of visible objects. From their blurring and doubling to the inability to see small objects at close range.

Refractometry Diagnosis

In order to expand the pupils and get more accurate results, the ophthalmologist prescribes a three-day preparation. For 3 days, a person should instill drops of Atropine into the eyes in the morning and evening. The concentration of the drug depends on the age of the patient. Adults and children over three years of age are prescribed a 1% solution, children who have not reached the age of three are 0.5% composition, infants under 1 year old are 0.1% drops.

The study itself is carried out using a computer autorefractometer, it takes no more than 3-5 minutes.

The ophthalmologist disinfects the surfaces that the patient will come into contact with, then:

Seats the person in front of the apparatus.
Helps to correctly position the head on the stand, turn it to the right angle.
Examines the right eye.
Shows the patient images that gradually change in clarity.
Adjusts the device so that infrared rays are directed to the center of the pupil of the eye.
Repeats diagnostic manipulations with the left eye.
Prints out the examination results.

During the procedure, the patient must not turn or move his head to the side, but is allowed to blink.

Harmless infrared rays pass through the optical system of the eye, are refracted, reach the retina and are then reflected. The device fixes the volume of the sent and reflected beam of light, the time it spent on it. The result is processed and issued after printing on a sheet. Based on accurate and reliable information, the doctor makes a diagnosis and determines which method of vision correction is suitable for the patient.

Designations and their interpretation

The vision test sheet reflects the parameters and digital indicators for the right and left eyes.

Index	Refractometry interpretation
Ref	Examination result
L	Left eye
R	Right eye
Sph	Refractive power of a spherical lens. The designation “-” indicates myopia, “+” indicates hyperopia, “0” indicates the norm.
Cyl	Anomalies of the cornea, shape of the eye or lens – optical power of a cylindrical lens. Reflects the degree of astigmatism, therefore it is taken into account when choosing lenses.
PD	Distance between two pupils
AVG/AVE	The radius of curvature of the cornea is its average value.
Axis/Ax	Angle to set lenses for astigmatism. Depending on the age of the patient, the value of the norm may vary.
VD	The distance that should be between the eye and the frame of the glasses. The vertex distance is 12 to 14 mm.
Ker	Curvature of the anterior wall of the cornea. This parameter is important when choosing contact lenses.
S.E.	Spherical equivalent. This is the summed value of the largest and smallest refraction of the eye.
R1, R2	The radius of curvature of the cornea, which was measured in its minimum and maximum meridian.

Ophthalmologists take into account that illness, fatigue and a number of other reasons can distort the results of the examination. Therefore, if the need arises, doctors prescribe a second study.

How Refractometry is Performed in Children

If a child’s head is fixed, this will automatically lead to pupil tension. In this regard, for children under the age of 4 years, the skiascopy method is often used. Other names for the procedure are retinoscopy, shadow test, and keratoscopy.

How an ophthalmologist examines the refractoriness of children’s eyes:

Seats the child on a chair.
It has a lamp on its side.
Sits in front of the child at a distance of 1 m.
Directs the light of the lamp at the mirror at an angle so that it hits the fundus of the eye.
Moves the skiascope up and down.
Tracks the displacement of the shadow area on the surface of the fundus.

When the doctor is examining a newborn, he or she may use medication to relax the eye muscles. To study the organs of vision of children 4-6 years old, an autorefractometer is used. Before the procedure, they are prescribed dilating pupil drops.

For the convenience of small patients, special corrective nozzles are used and they are allowed to be on the parent’s lap during the diagnosis. They, as in the diagnosis of adults, gently fix their heads on a stand and show pictures with changing clarity.

Immediately after a five-minute examination, parents receive the results on the form, a transcript from a specialist and personalized recommendations for correcting their child’s vision.

When computer diagnostics are contraindicated

Diagnosis can be hampered by a violation of the transparency of the light-refracting elements of the eye and some temporary human conditions.

Refractive analysis is not performed if the patient has:

Complete or partial clouding of the lens.
Vitreous opacity.
Clouding of the cornea.
Alcohol or drug intoxication because the person is unable to focus.
A mental disorder that prevents the patient from remaining still and following the instructions of the ophthalmologist.
Inflammatory eye diseases.
Allergic reaction to pupillary dilator.

If a person has ocular hypertension, then refractometry is performed, but without the use of Atropine solution or its analogues.

How refraction changes with age

People have different values of the curvature of the cornea and lens, the distance between these elements. All this makes the characteristics of refraction purely individual. At the same time, parameters change with age.

Babies, for example, are farsighted. People in their forties develop age-related farsightedness. In young people aged 20 years, 40% of cases are diagnosed with myopia, 30% with hyperopia, and 30% with normal vision.

In addition, it should be borne in mind that when examining the left eye, myopia can be detected, the other hyperopia, in addition, both anomalies can be combined with astigmatism. Often, diseases of the optical system and the body, corneal injuries provoke a decrease in visual acuity. Therefore, every year it is advisable to visit an ophthalmologist for a preventive check. Such a reasonable approach will stop the development of pathology and carry out a suitable correction.

05/06/2022

Services

Doctors

Ochirov Sanal Alexandrovich

Ophthalmic surgeon (Yaroslavl), the highest category

Semechkova Victoria Alexandrovna

Ophthalmic surgeon (Yaroslavl)

Edemskaya Olga Sergeevna

Ophthalmologist

Eliseeva Olesya Vasilievna

Ophthalmologist

Perova Tatyana Valentinovna

Pediatric ophthalmologist, 1st category

Article

Vision as it is

In the simplest sense, vision is primarily two eyes that receive and process information about the world around us. In fact, human vision, of course, is much more complicated, and information from the sense organs (that is, the eyes) goes through several stages of processing: both by the eye itself and then by the brain. Together with the 3Z Ophthalmological Clinic, we tell how the human visual system forms an image of reality, and explain why we do not see the world upside down, small, shaking and divided into two parts.

From your school physics course, you may remember lenses – devices made of a transparent material with a refractive surface, which, depending on their shape, can collect or scatter the light falling on them. We owe it to lenses that there are cameras, video cameras, telescopes, binoculars and, of course, contact lenses and glasses that people wear in the world. The human eye is exactly the same lens, or rather, a complex optical system consisting of several biological lenses.

The first of these is the cornea, the outer shell of the eye, the most convex part of it. The cornea is a concave-convex lens that receives rays from every point on an object and transmits them further through the moisture-filled anterior chamber and pupil to the lens. The lens, in turn, is a biconvex lens, shaped like an almond or an oblate sphere.

Biconvex lens – converging: the rays passing through its surface are collected behind it at one point, after which a copy of the observed object is formed. An interesting point is that the image of an object formed at the back focus of such a lens is real (that is, it corresponds to the same observed object), inverted and reduced. The image that forms behind the lens is therefore exactly the same.

The fact that the image is reduced allows the eye to see objects that are several tens, hundreds and thousands of times larger than it. In other words, the lens compactly folds the image and in the same form gives it to the retina, which lines most of the inner surface of the eye – the place of the back focus of the lens. Together, the cornea and lens are thus a component of the visual system that collects the scattered rays emanating from an object into one point and forms their projection on the retina. Strictly speaking, there is actually no “picture” on the retina: these are just traces of photons, which are then converted by the receptors and neurons of the retina into an electrical signal.

This electrical signal then travels to the brain where it is processed by the visual cortex. Together, these departments are responsible for converting signals about the location of photons – the only information that the eye itself receives – into meaningful images. At the same time, the brain is an interconnected system, and not only our eyes and visual system, but also other sensory organs that can receive information are responsible for how we perceive what is happening in reality. We do not see the world upside down due to the fact that our vestibular apparatus has information that we are standing straight, with two feet on the ground, and a tree growing from the ground, accordingly, should not be upside down.

Confirmation of this is an experiment that American psychologist George Stratton set up on himself in 1896: the scientist invented a special device – an invertoscope, whose lenses can also flip the image that the one who wears them looks at. In his device, Stratton walked for a week and at the same time did not go crazy from having to move in an inverted space. His visual system quickly adapted to the changed circumstances, and after a couple of days the scientist saw the world the way he used to see it since childhood.

In other words, there is no special section in the brain that flips the image received on the retina: the entire visual system of the brain is responsible for this, which, taking into account information from other senses, allows us to accurately determine the orientation of objects in space.

3Z Clinics

As for the retina itself, in order to understand how vision works, you also need to take a closer look at its functioning and structure. The retina is a thin multilayer structure that contains neurons that receive and process light signals from the optical eye systems and send them to each other and to the brain for further processing. In total, three layers of neurons are distinguished in the retina and two more layers of synapses that receive and transmit signals from these neurons.

The first and main neurons involved in the processing of light stimuli are photoreceptors (light-sensitive sensory neurons). The two main types of photoreceptors in the retina are rods and cones, named for their rod and cone shape, respectively. Rods and cones are filled with light-sensitive pigments – rhodopsin and iodopsin, respectively. Rhodopsin is many times more sensitive to light than iodopsin, but only to light with one wavelength (about 500 nanometers in the visible region) – this is why rods containing rhodopsin are responsible for human vision in the dark: they catch even the smallest rays, helping us to distinguish the outlines of objects, while not allowing you to accurately determine their color. But the “daytime” photoreceptors – cones – are already responsible for color perception.

Light-sensitive iodopsin, which is part of cones, is of three types, depending on the wavelength of light it is sensitive to. In the normal state, the cones of the human eye respond to light with long, medium and short wavelengths, which roughly corresponds to red-yellow, yellow-green and blue-violet colors (or, more simply, red, green and blue). There are different numbers of cones that contain one or another type of iodopsin in the retina, and their balance helps to distinguish all the colors of the surrounding world. In the case when cones with one or another type of iodopsin are not enough or simply not present, they speak of the presence of color blindness – a feature of vision in which recognition of all or some colors is not available. The type of color blindness directly depends on which cones “do not work”, but deuteranopia is considered the most common in a person – with it there are no cones whose iodopsin is sensitive to medium wavelength light (that is, they perceive green color poorly or do not perceive it at all) .

In this case, rods and cones do not cover the entire corresponding layer of the retinal surface: it contains the so-called blind spot, which does not contain photosensitive receptors at all. Since there are none, there is nothing to process the light within the borders of the spot – that is why those objects that fall into the “field of view” of the blind spot are invisible to humans. The vision of any person (fortunately or unfortunately) does not allow you to see these blind spots, but some diseases lead to the appearance of a scotoma (that is, a blind area in the visual field) and outside the corresponding place on the retina.

The signal received and processed by photoreceptors then passes to another layer of neurons – bipolar cells. Such cells are a kind of intermediaries that connect cones and rods with ganglion cells – retinal neurons that generate nerve impulses and then transmit them along the optic nerve to the visual cortex of the brain through the lateral geniculate body (a small tubercle on the surface of the thalamus).

The lateral geniculate body, having received signals from retinal ganglion cells, first transmits them to the primary visual cortex, the most evolutionarily ancient part of the visual system of the brain (also called V1 for convenience and brevity). At this point, the formation of an actual image of what is happening around us begins – the photons received by the eye begin to take shape, and the color, shape, presence of movement and other aspects of the image turn into electrical activity. Depending on what these signals convey (the movement of an object in space or its shape), they are then sent for processing along the ventral and dorsal pathways to other parts of the visual cortex. For example, the middle temporal visual area (its serial number is five, that is, it is briefly called V5) is considered part of the dorsal pathway, as it is responsible for motion processing, and the fourth zone (V4) is responsible for color processing, therefore it belongs to the ventral pathway.

Modern technologies help to solve vision problems. For the correction of myopia, hyperopia and astigmatism, 3Z clinics have collected 6 of the world’s best vision correction practices: ReLEx SMILE, ReLEx FLEx, Femto Super LASIK, Super LASIK, PRK and implantation of phakic intraocular lenses. The technology is selected individually for each patient to ensure the best result. Therefore, visual acuity after surgery is often 120% or even 150%.

The departments responsible for processing information from the sense organs and, as we have already found out, helping to recreate a picture of the real world to the visual system, are not the only parts of the brain that are involved in the process of vision. The motor cortex, which is responsible for processing movements, also plays an important role. The motor cortex is important because the eyes are constantly moving: shifting your gaze helps you follow a moving image or see something that is not entirely in the field of view.

In a calm state (when we look at a static object or even at the background), the eyes still move, making very fast synchronous movements (up to 80 milliseconds) – saccades. Information that the eye needs to change position is sent to it from the motor cortex. A little earlier, exactly the same (or at least similar) signal is sent to the visual cortex as a so-called “efferent copy”. This gives the visual cortex information that the eye will move before the movement even starts, which helps the visual cortex to ignore possible small movements.

Finally, it remains to deal with one more point – why the picture of reality that we see is not divided into two parts. Humans, like other vertebrates, have one pair of eyes. They are located quite close to each other: the holes in the eye sockets of the skull provide the location of the eyes in such a way that each of the eyes, on the one hand, has its own field of view (about 90 degrees for each eye – that is, a little more than 180 in total), and on the other – 60 degrees of the central field of view, which intersect with each eye. Due to this intersection, the images received by one and the other eye are combined into one image in the center of the common field of view. The same intersection of visual fields provides us with stereoscopic (or binocular) vision and the ability to perceive depth. Binocularity of vision is lost in some forms of strabismus – and with them the normal ability to perceive depth is also lost.

Therefore, the mechanism of how the image of reality is formed in our brain is not only optics and chemical reactions occurring on the retina. The most important role in creating this picture is played by our brain – and not only the visual cortex, which makes the figures voluminous, separates them from the background and paints them in the right colors, but also other departments that are responsible for vital functions.

The 3Z clinic treats all types of visual impairments due to an irregular shape of the eye (nearsightedness and farsightedness) or excessive curvature of the cornea (astigmatism). Until July 15, vision correction in 3Z can be done in installments without an advance payment and overpayments.
The promotion is valid for all types of laser vision correction, as well as for the implantation of phakic intraocular lenses (PIOL).

Eye crossing pictures. Adult Strabismus: Causes, Symptoms, and Treatment Options for Crossed Eyes

Understanding Adult Strabismus: More Than Just Crossed Eyes

The Mechanics of Eye Movement

Causes of Adult Strabismus: Unraveling the Triggers

Health Conditions Associated with Strabismus

Trauma and Injury

The Impact of Strabismus on Adult Vision

Normal Vision vs. Strabismic Vision

Childhood vs. Adult-Onset Strabismus

Recognizing the Symptoms of Adult Strabismus

When to Seek Medical Attention

Comprehensive Treatment Options for Adult Strabismus

Surgical Intervention: Realigning the Eyes

Non-Surgical Treatment Options

The Importance of Timely Treatment for Adult Strabismus

Benefits of Treating Adult Strabismus

Living with Strabismus: Coping Strategies and Support

Adaptive Techniques

Emotional and Social Support

Advances in Strabismus Research and Future Treatments

Emerging Technologies

Personalized Treatment Approaches

Preventing Complications of Adult Strabismus

Regular Eye Examinations

Managing Underlying Health Conditions

Protecting Eyes from Injury

The Role of Vision Therapy in Adult Strabismus Management

What is Vision Therapy?

Benefits of Vision Therapy for Strabismus

The Vision Therapy Process

What Is Adult Strabismus? – American Academy of Ophthalmology

There Are Six Eye Muscles That Control Eye Movement

What Causes Adult Strabismus (Crossed Eyes)?

How Does Adult Strabismus Affect Vision?

What Are the Symptoms of Adult Strabismus (Crossed Eyes)?

Adult Strabismus (Crossed Eyes) Treatment

Adult strabismus (crossed eyes) surgery

Eye muscle exercises

Prism eyeglasses

Botulinum toxin (Botox®)

It Is Never Too Late to Treat Strabismus

crosseyed photos on Flickr | Flickr

Eye Refractometry | Refractometry interpretation

What the refraction of the eye says

Reasons for the examination

Refractometry Diagnosis

Designations and their interpretation

How Refractometry is Performed in Children

When computer diagnostics are contraindicated

How refraction changes with age

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