Focus on Strabismus


Please note that this page is for information only, it is not a replacement for medical advice.
If you have any questions regarding strabismus or any other eye condition, please consult a medical professional. 

What is Strabismus?

Strabismus is the medical term also known as ‘a squint’ in the UK and often referred to as ‘crossed eyes’ in the US. It’s a visual condition in which the eyes are misaligned and do not point in the same direction. In strabismus, one eye may look straight ahead while the other eye may turn inward, outward, upward, or downward.

With strabismus, each eye is taking quite different points of view. This means the brain can have difficulty ‘matching’ these to form a picture, which can result in blurred or double vision.

This misalignment can lead to problems with depth perception, and can cause the brain to suppress or ignore the input from the misaligned eye, which can eventually lead to amblyopia or "lazy eye."

Strabismus can be caused by a variety of factors, including problems with the muscles that control eye movement, nerve problems, or a combination of both. Treatment options for strabismus include glasses, prisms, vision therapy, and surgery to realign the eyes. Early detection and treatment of strabismus is important to prevent vision problems and other complications.



"Most strabismus develops in young children. Strabismus can also develop in adults, but an adult will develop strabismus for different reasons than a child."

RNIB Strabismus Factsheet



Symptoms of Strabismus

The most noticeable symptom of strabismus is the misalignment of the eyes. Depending on the type of strabismus, the eyes may appear to be crossed, turned outward, upward or downward. Other symptoms of strabismus may include:

Double vision

When the brain receives two different images from each eye, it may perceive double vision.

Head tilting or turning

To compensate for the misalignment of the eyes, some people with strabismus may tilt or turn their head in a certain direction.

Eye strain or fatigue

People with strabismus may experience eye strain or fatigue, particularly when performing visually demanding tasks such as reading or driving.

Difficulty with depth perception

Squinting or closing one eye

If you or someone you care for is experiencing any of these symptoms, it's important to see a qualified optometrist or ophthalmologist for an evaluation.

Early diagnosis and treatment of strabismus can help prevent further complications and improve vision.


How someone with Strabismus might view the world  

Image shows young children and a teacher in a classroom. Each item in the class appears as a double, overlapping image, which gives a blurred impression.      

Please note this is a simulation of strabismus, based on the anecdotal experiences of people who have the condition.
This image is not the experience of everyone with strabismus and is for illustration purposes only.


Diagnosis of Strabismus

Strabismus can be diagnosed through a comprehensive eye examination, performed by an optometrist or ophthalmologist, or a specialist in strabismus. The examination may include:

A visual acuity test

This measures the sharpness of vision in each eye using an eye chart.

A cover test

This test involves covering one eye at a time while the patient focuses on an object. The doctor will observe whether the covered eye moves to focus on the object when uncovered, which can indicate a misalignment.

An eye movement test

This measures the ability of each eye to move in all directions, and can detect problems with eye coordination.

Refraction test

This measures the refractive error (i.e. short / near sightedness, long / far sightedness, or astigmatism) of each eye and determines whether corrective lenses are needed.

Pupil response test

This measures the reaction of the pupil to light, and can detect abnormalities in the eye muscles or nerves.

Binocular vision assessment

This evaluates how well the two eyes work together to perceive depth and alignment.

In some cases, additional tests such as imaging studies or specialised eye tests may be needed to further evaluate the condition. Once a diagnosis of strabismus is made, appropriate treatment can be initiated to correct the alignment of the eyes and prevent further vision problems.



"Strabismus usually develops in infants and young children, most often by age 3." 

American Optometric Association


Treatment of Strabismus

The treatment of strabismus depends on the severity of the condition and the underlying cause.

Treatment options for strabismus may include:

Glasses or contact lenses

Corrective lenses can help improve vision and eye alignment in some cases of strabismus.

Vision therapy

This is a type of eye exercise program that can help improve eye coordination, visual processing, and eye movements.

Patching therapy

Patching therapy involves covering the 'good' eye with an eye patch to force the brain to use the misaligned eye, which can help improve visual acuity in the weaker eye.

Prism glasses

Special glasses with prism lenses can be used to redirect the light and help improve eye alignment.


In some cases, surgery may be recommended to correct the alignment of the eyes. This may involve tightening or loosening the muscles that control eye movement.

The most appropriate treatment option for strabismus will depend on the type, severity, and underlying cause of the condition.

It's important to consult with an optometrist or ophthalmologist or a specialist in strabismus to determine the best course of treatment for each individual case. Early diagnosis and treatment of strabismus can help prevent vision problems and other complications.

"The prevalence of strabismus is between 2% and 5% of the general population". 

Living with Strabismus

Most people lead full and independent lives while living with strabismus. There are of course challenges to living with strabismus, though there are steps that can be taken to manage the condition, minimise its impact and improve quality of life.

Here are some tips for living with strabismus:

Seek treatment

If you have strabismus, it's important to see an optometrist, ophthalmologist or a specialist in strabismus for a comprehensive eye examination and appropriate treatment. Early diagnosis and treatment can help prevent vision problems and other complications.

Wear corrective lenses

If you have a refractive error which means you are short-sighted (nearsighted), long-sighted (farsighted), or have astigmatism, wearing corrective lenses can help improve vision and eye alignment.

Practice good eye health

Maintaining good eye health is important for people with strabismus. This includes getting regular eye exams, protecting your eyes from injury, and avoiding activities that can strain the eyes.

Use assistive technology

Assistive technology, including screen magnifiers, screen readers and accessible book readers and text-to-speech software, can help you navigate your daily life. These tools can make it easier to read, write, study and use technology.

Whatever your experience is with computers, Dolphin assistive technology can help. 

Develop coping strategies

Living with strabismus can be challenging - especially if it affects self-esteem or social interactions. Developing coping strategies such as positive self-talk, relaxation techniques, and seeking support from family and friends can help.

Avoid triggers

Some people with strabismus may experience symptoms such as eye strain, double vision, or fatigue in certain situations. Avoiding triggers such as bright lights or reading in dimly lit areas can help reduce these symptoms.

Consider vision therapy

Vision therapy is a type of eye exercise program that can help improve eye coordination, visual processing, and eye movements. It may be recommended by your optometrist or specialist in strabismus.

Help educate others

It's important to educate others about strabismus to help reduce stigma and promote understanding. Letting people know about the condition and its effects can help foster empathy and support.

Living with strabismus may require some adjustments and accommodations, but with appropriate treatment and support, most people with strabismus lead full and fulfilling lives.


Where to find more information about Strabismus

RNIB Logo-1

Royal National Institute for Blind People 

RNIB provides information, advice and support for people with strabismus and other visual impairments and sight loss conditions.  

Visit RNIB >

NHS Logo

NHS Website

To find out more about Strabismus and learn when and how to get treatment in the UK, visit the NHS Health website. 

NHS Squint >

AOA logo

American Optometric Association (AOA)

The leading authority representing more than 48,000 doctors of optometry, optometric professionals and optometry students.

Visit AOA website >

Dolphin Computer Access Logo

How Dolphin assistive technology can help you live with Strabismus

How Dolphin makes a difference

Dolphin Computer Access Logo Hi res-1

If you are blind or partially sighted, Dolphin assistive technology helps you maintain your independence. We have developed specialist software, specifically for people experiencing sight loss.

For over 35 years, we have made a difference to the lives of millions of people who are blind or partially sighted.

Dolphin software includes screen magnification and screen reading technology, book reading apps and easy to use computer programs. These work to help people with sight loss to work or study, to complete tasks independently at home, to access the internet and read all the information on a computer screen.

Assistive Tech for Home

About SuperNova

Dolphin SuperNova Logo

SuperNova is a range of assistive technology for people who are blind or partially sighted. SuperNova provides exceptional magnification, screen reading and braille support and enables you to explore your computer screen. 

Choose the edition that suits your vision:

  • SuperNova Magnifier
  • SuperNova Magnifier & Speech
  • SuperNova Magnifier & Screen Reader
  • SuperNova Enterprise

SuperNova Information

Find out more about Dolphin Computer Access

Subscribe to newsletters

If you would like to find out more about the Dolphin assistive technology available for people who are blind or partially sighted, or how Dolphin technology can help people with neurodiversity including dyslexia, sign up for Dolphin newsletters.

We usually send out an email each month, with up to date information on accessibility and how Dolphin assistive tech helps people in different situations - including education, work and at home. These emails also highlight the events we attend each month, and the webinars which can help you find out more about Dolphin assistive tech. 

Join our mailing list