hotline no. 0124 4834505

Request a Call-back

Fill in the following details and we will call back:

Feedback

Squint

Introduction

A squint is a condition where the eyes point in different directions.

One eye may turn inwards, outwards, upwards or downwards while the other eye looks forward. The medical name for a squint is strabismus.

Squints can also cause:

  • - Blurred vision
  • - Double vision
  • - Lazy eye (amblyopia) – when the brain starts to ignore signals coming from the eye with the squint

       

Symptoms

The most obvious sign of a squint is eyes that look in different directions. Most often, one eye turns inwards (convergent squint) or outwards (divergent squint). In rare cases, it may turn up or down (vertical squint). They can either be apparent at all times (constant), or only be apparent at certain times (intermittent). Minor squints are not always obvious.

Causes

The exact cause of a squint is not always known. In most cases, babies are born with a squint or develop one because of a problem with their vision. If a baby is born with the condition, it is called a congenital squint. Squints that develop later are called acquired squints.

Refractive errors

Acquired squints are sometimes caused by the eye's inability to focus light that passes through the lens. This is known as a refractive error. Types of refractive errors include:

  • - Short-sightedness (Myopia) – a sight problem that affects your ability to see distant objects
  • - Long-sightedness (Hyperopia) – a sight problem that affects your ability to see close-up objects
  • - Astigmatism – where the cornea at the front of the eye is unevenly curved, which causes blurred vision

Other causes

Although most squints are congenital or caused by refractive errors, in rare cases they are the result of:

  • - Childhood illnesses, for example viral infections such as measles, although it is possible these illnesses simply accelerate a squint that would have developed anyway
  • Some genetic conditions, such as Down's syndrome
  • - Hydrocephalus, which is caused by a build-up of fluid in the brain
  • - Other eye problems, such as abnormal development of the muscles that move the eye, or a problem with the retina (the layer of light-sensitive nerve cells at the back of the eye).

Risk factors

Some things may increase the risk of having a squint, which may include:

  • - Having a family history of squints, lazy eye (amblyopia) or needing glasses
  • - Having a condition that affects the nervous system, such as cerebral palsy
  • - Being born early (prematurely) or with a low birth weight

Tests and diagnostics

Sight tests

Different tests can be used to help diagnose a squint and assess the level of vision. These will vary according to your age, but may include:

  • - Looking at a light
  • - Matching letters and pictures
  • - Reading a letter chart
  • - Looking at visual targets at different distances, first with one eye covered and then the other

Other tests may also be needed to determine whether glasses are needed. Retina and optic nerve examination to make sure there are no other problems. In most cases, eye drops will be used to widen the pupils before the eyes are examined. This will make it easier for the ophthalmologist to study the back of the eyes.

Treatment

Treatments available for squints include:

  • - Glasses are one of the most common treatments for squints. They can be used to correct the vision problems (refractive errors) that may be causing the squint, such as:
    • - short-sightedness (myopia)
    • - Long-sightedness (Hyperopia)
    • - An unevenly curved cornea (astigmatism)
  • - Eye exercises - In some cases, it may be possible to treat a squint using special eye exercises that help the eyes work together.
  • - Botulinum toxin injections - It can be injected into one of the muscles that move the eye. The injection temporarily weakens the injected muscle, allowing the eyes to realign. The effects of botulinum toxin usually last around three months. After this time, the eyes may stay in position or they may go back out of alignment and require further treatment.
  • - Corrective surgery - If treatment doesn't work, surgery may be recommended. Surgery can be used to:
    • - Improve the alignment of the eyes (and therefore their appearance)
    • - Help the eyes work together