Strabismus: Definition, Types, Symptoms, Causes, Risk Factors, Treatment and Precautions

A simple definition of strabismus-strabismus is misalignment of the eyes.

It is commonly called “crossed eyes” and affects five to 15 million people in the United States alone.

It includes any type of misalignment, such as one eye pointing in, out, up, or down rather than in the same direction as the other eye.

Fortunately, many cases of strabismus can be improved with treatment. The goal of treatment is to help minimize vision problems. By getting treatment for strabismus and taking steps of your own to care for your vision, you can help resolve or improve the condition.

What is strabismus?

Strabismus is a condition that causes the eyes to look in different directions. It happens when the muscles that control one of the eyes do not keep it aligned correctly with the other. This can result in double vision. Strabismus can coexist with other eye problems, such as:

  • Problems moving the eyes correctly.
  • Not being able to see well.
  • Have eye pain or discomfort.
  • Headaches.
  • Hold your head at odd angles.

Cross-eyed doesn’t go away on its own. If left untreated, strabismus can worsen and cause lazy eye , permanent vision loss, blurred vision, eye strain , poor depth perception, low self-esteem, tiredness, and headaches.

These problems can in turn lead to other problems, such as injury, blindness , poor quality of life, poor academic or work performance, low productivity, and limited social interaction.

Many people with this condition have crossed eyes all the time, but in some people it comes and goes (known as “intermittent” strabismus). It can occur at any age, but most cases affect children and begin before they are 6 years old.

Types of strabismus

There are many ways to categorize this condition. These include:

The direction of the misaligned eye:

  • Eyes inward (stripe).
  • Eyes out (exotropia).
  • Looking up (hypertropia).
  • Downward gaze (hypotropia).

When the problem starts:

  • Childhood.
  • Early childhood (usually 2 or 3 years of age).
  • Adolescence.
  • Adulthood.

Which eye is affected:

  • The same eye is constantly affected.
  • The same eye is affected sometimes yes sometimes no.
  • The problem changes between the eyes.

How bad is the misalignment:

  • Light.
  • Moderate.
  • Grave.

Possible cause of the problem:

  • Inherited (runs in the family).
  • Poor vision
  • Injury.
  • Stroke.
  • Tumor.
  • Infection or other problems with the eye.
  • Unknown cause.

The type of strabismus you have can dictate the type of treatment you need.

Is lazy eye the same as strabismus?

Strabismus vs. Amblyopia: What’s the Difference? Strabismus is being crossed, while amblyopia is a condition known as lazy eye. The two conditions may appear the same to an observer, as amblyopia can also cause one eye to drift inward or outward.

In fact, strabismus is the most common cause of lazy eye. However, lazy eye is due to the vision of one eye not fully developing, and it can occur even without being crossed.

When the weak muscles that cause strabismus keep one eye pointing in the wrong direction, the brain stops tracking the mismatched eye input. Vision becomes poor in that weak and “lazy” eye.

Alternatively, something can happen to cause poor vision first, and eventually the brain ignores the images coming from that eye.

Fortunately, both lazy eye and crossed eyes can usually be treated effectively, especially if caught early. But as is the case with all functional vision problems, they can be treated at any age.

Can strabismus be prevented?

Most cases of strabismus in children have no known cause. Additionally, many of the known causes of strabismus cannot be prevented, such as birth defects, genetic conditions, strokes, and other health problems.

While people can do whatever they can to protect themselves from these possible causes, they may or may not help prevent strabismus. However, regular eye exams can help identify the risk of squinting early, before it results in a complete strabismus.

Some cases seem to run in families. While these cases cannot be prevented, anyone with a family member who has crossed eyes should receive an early and regular vision evaluation.

The muscle weakness that often leads to strabismus in very young children can be detected and corrected before it results in complete misalignment.

In general, while it cannot be prevented, complications of strabismus can be avoided if the condition is caught early and treated appropriately.

Can strabismus be treated?

In most cases, strabismus can be treated effectively. The goal of treatment is to preserve or restore vision. Whether it can be completely corrected, restoring both the appearance of the eyes and their vision, depends on its cause and how long it was not treated.

Most people with strabismus who are treated early (before age 6) have an excellent prognosis. Strabismus in adults can also be treated effectively.

However, there are cases where the alignment of the eye after treatment is not perfect or returns to misalignment over time. Some people also do not regain full vision even with treatment.

Signs and symptoms of strabismus

In children with strabismus, symptoms usually appear before the age of 3, but most often by the age of 6. However, older children and adults can also develop crossed eyes.

Signs and symptoms of strabismus include:

One eye pointing in the wrong direction (turned inward or up or down). One eye that moves or shifts while the other eye is in focus. Squinting one eye. Frequent blinking, especially in bright sunlight.

Rub one or both eyes constantly. Tilt or move your head to see something better. Double vision and split vision (seeing a regular image plus a half or partial).

View shaky or moving images. Eye fatigue or tension. Headache. Bad depth perception. Constant or occasional trouble focusing, especially when you are tired or ill.

Eye doctors can also see signs of strabismus in the eye muscles and movement during an exam.

Causes and risk factors

The causes of strabismus and risk factors vary by age. In most cases, there is no known cause and the condition occurs early in life. However, strabismus causes and risk factors include:

  • Family history of crossed eyes.
  • Stroke.
  • Poor vision (farsightedness) or loss of vision.
  • Head or brain trauma.
  • Eye wound.
  • Cerebral palsy.
  • Down syndrome.
  • Hydrocephalus (a buildup of fluid in the head that occurs in some newborns).
  • Brain tumor or nervous system problem.
  • Graves’ disease.
  • Apert syndrome.
  • Rubella in newborns.
  • Hemangioma near the eye in babies.
  • Incontinentia pigment syndrome.
  • Noonan syndrome.
  • Prader-Willi syndrome.
  • Eye problems in the newborn such as retinopathy or retinoblastoma.
  • Trisomy 18.
  • Botulism.
  • Diabetes.
  • Síndorme of Guillain-Barré.
  • Shellfish poisoning.

Conventional treatment

Begin treatment as soon as you can. If you don’t, the condition could continue into adulthood. Most cross-eyed adults were born that way.

Talk to a pediatric ophthalmologist , an ophthalmologist who specializes in working with children.

People who have other eye problems, such as lazy eye or cataracts, usually receive treatment for those conditions before starting strabismus treatment.

Conventional treatments for people with crossed eyes generally depend on the type of alignment problem they have. In some cases, treating an underlying condition (such as a brain tumor) can resolve strabismus without having to specifically treat the alignment problem.

You can expect at least one of the following crossed eye treatment recommendations:

  • Eyeglasses.
  • Eye exercises.
  • Prisms (thick prismatic glasses to reduce how much the eye must rotate).
  • You can start treatment with a patch to force your child to wear the deviated eye until they see normally.

So is using drops to blur the vision of the strong eye (this forces the weaker eye to try to align and focus). The main goal is to make the problem eye work as it should before your child is 8 years old. After that, permanent vision loss can set in.

Is surgery an option?

Vision correction is the first step in almost all strabismus treatment plans. Then, if the eyes don’t move together after glasses or a patch improve vision, surgery may be necessary.

It works best when done during childhood, but adults can have it too. Most people recover from surgery within a few days.

The surgeon opens the outer layer of the eyeball to reach a muscle. To strengthen the muscle, the surgeon removes a small section from one end and it is put back in the same place. This makes the muscle shorter, which causes the eye to turn to that side.

To weaken a muscle, the doctor moves it back or makes a partial cut through it. The eye moves away from that side. Any double vision after surgery should go away within a few weeks as the brain adjusts to the improved vision.

However, many people may need glasses permanently, and some people may need more than one operation. If strabismus is not treated early, it can lead to permanent vision loss.

Natural ways to improve the symptoms of strabismus

In the case of strabismus, many treatments recommended by ophthalmologists can be considered natural.

Most conventional treatments for people with crossed eyes do not require medication. Two natural ways to improve symptoms, in addition to glasses, include:

  • Strabismus exercises.
  • A formal vision therapy program (orthoptics).

Please note that you should not attempt to create your own strabismus treatment plan without consulting an eye doctor.

This is because strabismus can coexist with other eye problems, or it can be another eye problem that simply looks like a crossover in the eyes. Professional diagnosis and treatment is essential.

Strabismus exercises

These exercises are exactly what they sound like: a workout for your eye muscles. While eye exercises alone are not enough to correct crossed eyes in most cases, they are often an important part of a treatment plan.

In general, these exercises can be done two to 10 times per day, and should only take a few minutes to complete. Exercises for crossed eyes include:

Pencil Push-Ups : Hold a pencil at arm’s length, with the tip pointed away from your eyes. Focus on the draft. Slowly bring the eraser up to the bridge of your nose.

Follow it with your eyes until you can no longer see it clearly. Move the pencil back to arm’s length and repeat several times.

Trombone Exercise : Like the push-ups with pencils, this exercise consists of holding a small object with the arm extended. However, you must cover your good eye.

Keep the object where your weak eye normally points. Keep your head pointed forward. Focus on the object with your weak eye and move the object until your eye is looking directly in front of you. Try to keep the subject in focus. Repeat this up to 20 times, varying the speed and distance of the object.

Rope Exercise : Slide three different colored beads at equal intervals on a rope about 5 feet long. Tie one end of the string to something that won’t budge, such as a table, railing, or cabinet knob.

Hold the other end firmly against your nose so the string is taut. Focus on the account closest to you. It should appear only at the cross of an X made up of identical doubles of the string in front of and behind the bead.

If you see a crossed thread in front of or behind the bead, your eyes will not focus properly on the bead. Once you see the account in the center of the X, shift your focus to the central account. It should look the same: a single bead in the center of an X made from the images of the rope.

Once the center bead is in focus, shift your gaze to the farthest bead. It should be at the point of an inverted V, where the two lines of the V are the identical string images coming your way. Once you can properly focus on all three beads, move them around the string and do the exercise again.

Barrel Cards – Draw three barrels in a row in red ink on a letter. One should be large, the middle one should be medium in size, and the other should be small. Flip the card over. Draw matching barrels on the opposite side in green ink.

Hold the card against your nose with the largest barrels furthest from your eyes (directly from your face) and the smallest barrels closest to your nose.

Focus on the far away barrels until they blend into one image. The other barrels should still appear double. Hold your focus for about five seconds. Repeat the exercise with the medium and small barrels.

Rotating Mirror – Stand with your back to a mirror, feet far enough apart so that you don’t lose your balance when you turn. Cover your good eye and look ahead with your weak eye.

Turn your upper body to the side of your weak eye (for example, if your left eye is weak, turn to the left to look back). Move your weak eye until you can see your eye in the mirror. Then return to the starting position.

Repeat this process up to six times, then cover your weak eye and repeat the exercise with your strong eye.

Side Bends : Stand with your feet shoulder-width apart. Raise your hands out on each side, at shoulder height.

Turn your head and weak eye to look at the hand that is in the opposite direction that your weak eye is pointing (for example, if it is pointing to the left, look to the right hand).

Bend your upper body to the other side so that the hand you are looking at goes toward the ceiling and the other hand toward the floor. Slowly return to the starting position. Repeat the exercise looking at the other hand and tilting the other direction.

Vision therapy (orthoptic)

Vision therapy programs are developed by an ophthalmologist and are often practiced both in the doctor’s office and at home. They usually combine a series of doctor-performed eye exams with weekly or monthly eye exercise routines.

The doctor will have the patient practice the exercises in the office to make sure they are doing them correctly, and will then check the progress in eye alignment at each visit. These programs are often used for people with occasional strabismus.

In professional vision therapy programs, the doctor prescribes exercises that target a particular alignment problem. Some eye treatment centers offer digital programs that have eye exercises or games for children or adults to do while looking at a computer screen.

Over time, the specific exercises your doctor recommends may change based on your symptoms. The therapy program can improve the muscles of the weak eye, so regular observation and testing by your eye doctor will help you know sooner if your efforts are effective.


Do not try to diagnose strabismus without the help of an eye doctor. It can be confused with other neurological conditions or disorders. In some cases, the eye control problem can also be a sign of a serious underlying health problem, such as a brain tumor.

It is essential that crossed eyes, double vision or other problems that control or focus the eyes are evaluated by a professional.

Don’t avoid conventional treatment in the hope that crossed eyes will go away on their own. In addition to the cases in babies that sometimes disappear within a few months, strabismus requires treatment.

Although not everyone will need glasses or surgery, most people require more than vision therapy and eye exercises to regain normal eye alignment. The eye exercises in this article are not a substitute for specific exercise advice and care from an ophthalmologist.

If strabismus is not properly treated at an early stage, it can lead to permanent vision loss or vision problems.

Key points of strabismus

Strabismus includes any type of ocular misalignment. It is commonly called “crossed eyes,” but the weak eye can point in any direction: in, out, up, or down. Misalignment is caused by weak eye muscles that cannot control where the weak eye looks.

The condition is most common in young children, although it can occur at any age. In most cases, the cause of strabismus is unknown. However, causes include birth defects, strokes, brain injuries, diabetes, and other diseases.

Conventional treatment generally includes glasses and surgery. Underlying vision problems, such as cataracts or farsightedness, can be treated before proceeding with specific treatment for strabismus.

Strabismus should not be left untreated, as it can lead to permanent vision damage. When treated early, this vision problem can usually be corrected so that the eyes align.

Natural therapies to help improve the symptoms of strabismus include:

  • Eye exercises for strabismus.
  • Formal vision therapy programs.