If someone has a squint (strabismus), their eyes don't align properly when looking at an object.


If someone has a squint (strabismus), their eyes don't align properly when looking at an object. This may happen all the time or it may come and go. The eyes don’t look in the same direction and the pictures taken by the eyes can't be merged into one image in the brain. There are many causes. It’s important to diagnose this condition at an early stage in order to take the required measures.


Concomitant squint

  • Mostly occurs in children
  • Angle of deviation (squint angle) is the same in all directions

Latent squint

  • “Hidden” squint, “wall eye”
  • No deviation from the normal visual axis, hardly recognisable
  • Appears when tired, stressed, drinking alcohol
  • Blurred vision, possibly double vision

Paralytic squint

  • Caused by paralysis of the eye muscle; classified according to the deviation of the visual axis:
    • Convergent squint (eye turns inwards)
    • Divergent squint (eye turns outwards)
    • Hypertropia (eye turns upwards)
    • Cyclotropia (rotational strabismus)
  • Double vision (can cause dizziness and nausea)

Causes and treatment


Further treatment by your doctor / in hospital

Concomitant squinting is usually identified during the first months of life. Without treatment, 90% of children who squint will have poor eyesight for life (amblyopia).

Possible tests
  • Eye test (if possible)
  • Measurement of angle of deviation
  • Cover-uncover test
  • Neurological examination
Possible therapies

Early treatment prevents permanent long-term damage

  • Spectacles to correct poor eyesight
  • Temporary covering of healthy eye (eye occlusion patch)
  • Operation to correct misalignment
  • Vision training (orthoptics)

What can I do myself?

  • Careful observation of child

When to see a doctor?

Take note of the following in yourself/your child:

  • Angle of head
  • Sensitivity to light, tearful eyes
  • Screwing up the eyes, cloudy cornea
  • Inept movements, uncoordinated grasping
  • Headaches, concentration difficulties
  • Vision problems (e.g. blurred, double vision)
  • Misaligned eyes

Further information

Swiss Society of Ophthalmology (Schweizerische Ophthalmologische Gesellschaft)


squint, squinting, squint-eyed, strabism, strabismus, heterotropia, heterophoria, cross-eyed

Exclusion of liability

CSS offers no guarantee for the accuracy and completeness of the information. The information published is no substitute for professional advice from a doctor or pharmacist.