Condition

Squint (strabismus)

A squint, also know as strabismus, is a condition where both eyes don’t point in the same direction at the same time. It’s more common in children than adults, and causes in children tend to be different too.

What is a squint (strabismus)?

Strabismus, also known as a squint, is a condition where both eyes don’t point in the same direction at the same time. It’s more common in children than adults, and the causes in children tend to be different too. Doctors use the word squint to describe strabismus, but the word is also used by the public to describe narrowing the eyes to see better or in bright light.

What are the symptoms of a squint?

A squint can cause a range of symptoms, including:

  • Double vision
  • Headaches
  • Eye strain
  • Holding your head in an uncomfortable position
  • Blurred vision
  • Problems with depth perception.

What causes a squint in children?

  • A family history of the condition2
  • Uncorrected longsightedness (hyperopia), which can cause severe eye strain, forcing eyes to cross over and face in opposing directions
  • Eye disease, such as congenital cataracts
  • Some neurological or developmental disorders, including Down Syndrome, which has been closely linked to increased risk of developing strabismus.

What causes a squint in adults?

  • A re-emergence of childhood strabismus
  • Graves’ disease, which is an autoimmune condition that can affect the muscles around your eyes
  • Neurological damage, such as that caused by a stroke, brain tumour or traumatic injury to the brain
  • Some circulatory and systemic diseases, like diabetes, high blood pressure and multiple sclerosis

What are the different types of squint?

Illustrated medical infographic titled “Squint Eye (Strabismus)” showing four common types of eye misalignment. The image presents pairs of eyes demonstrating: Esotropia (eye turns inward), Exotropia (eye turns outward), Hypertropia (eye turns upward), and Hypotropia (eye turns downward). Each condition is labeled with its name and a brief description, with the misaligned eye position clearly illustrated for comparison. Gray background with realistic drawings of eyes and eyelids.

Esotropia/convergent squint

With esotropia, one or both eyes turn inwards towards your nose, which can make you look cross-eyed.

Exotropia/divergent squint

In exotropia, one or both eyes turn outwards, towards your ears.

Hypertropia

With hypertropia, one eye is pointed upwards, towards your forehead.

Hypotropia

In hypotropia, one eye points downwards, towards your chin.

Intermittent squint

As you may have guessed, an intermittent squint comes and goes. Many people find that they get worse when they are stressed or tired.

Consecutive squint

This is the name given to a squint that develops following a previous squint surgery. The most common type is a divergent squint in adults following surgery for a convergent squint in childhood.

How is a squint treated?

The most common treatment for a squint is squint surgery (strabismus surgery). The operation works by adjusting the position or strength of one or more eye muscles to improve eye alignment, helping the eyes work together more effectively and reducing symptoms such as double vision or blurred vision.

If you have a squint that is left untreated, it could result in permanent vision problems including blurred or double vision, a lazy eye and problems with depth perception that make everyday movement and judgement less safe. For example, you may not be able to correctly judge how far apart steps are to safely move up and down stairs, or how close a travelling car is.

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