Strabismus or heterotopia commonly known as squint eyes is a condition of the eye wherein both eyes are misaligned. While it is a condition that is fairly common among children, it also occurs among adults.

Types of Squint

There are different types of conditions. But these can be broadly classified into three.

  1. Esotropias and Exotropias – Esotropias is when one of the eyes turns in towards the nose while the other focuses on a point ahead. If one eye turns outwards when the other is focused ahead; the type of squint is called Exotropias
  2. Hypertropias and Hypotropias – When one eye is placed higher than the other, then the condition is called Hypertropias whilst, if one eye is placed lower, it is known as Hypotropias.
  3. Paralytic Squints – When poor blood supply causes damage to nerves connecting eye muscles, it results in partial eye movements and squint.

Risk factors

Risk factors for Strabismus/Squint includes low birth weight, smoking throughout pregnancy, prematurity, cicatricial retinopathy of prematurity, anisometropia, hyperopia, and inheritance.


  1. Congenital Squints: The causes of this type of squint are not completely known. In these cases, the child suffers from squint either from birth or develops it within the first 6 months of growth. Most of the time, congenital squints feature eyes that are turned inward.
  2. Refractive Errors: Short sight, long sight, and astigmatism are refractive errors. In the case of astigmatism, the cornea of the eyes becomes oval-shaped rather than round. Due to this, if a child tries to see clearly by focusing too much, there is a chance an eye might turn. It usually happens with children older than two years.
  3. Other Causes: A squint might also develop in children suffering from cerebral palsy, Noonan syndrome, hydrocephalus, and brain injury.


Symptoms include double vision, eye strain, depth perception loss, inability to read comfortably, fatigue setting in quickly while reading and unstable vision.


Routine checkups must be conducted to detect any eye problems in children. If a child is suspected to have squints he should be examined by an orthoptist (a person who specialized in dealing with children’s squints and amblyopia). If it is a necessity, the child will be referred to an ophthalmologist for detailed treatment.


Judicious patching and special glasses should be tried first in the case of constant squinting. If there is no improvement, vision therapy or eye surgery needs to be considered. Intermittent squinting on the other hand might be a symptom of developing binocular vision. Hence there are chances that the brain will help in retaining the normal functioning of the eyes.

Preventive Measures

  1. Inheritance is a major cause of squint. So it is ideal to avoid marriages between blood relations.
  2. Practice convergence exercises that help in improving eye movements and coordination.
  3. Contact and exposure to bright light should be avoided
  4. Make routine eye checkups and treat all eye defects as soon as possible

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