Under normal circumstances, both the eyes should be perfectly aligned and should move together, in every direction of gaze. No matter in which direction we look, both eyes should move together to fixate on the object of our interest.

If this harmony of movement is disturbed and the eyes lose their coordination, then the condition is known as squint or strabismus.

Squints can occur due to various reasons and two people with squints that look exactly the same, may have widely different underlying disorders that has led to the development of the squint. For this reason, two people with similar looking squints, may need completely different treatments. A patient with squint may therefore, need multiple visits to the strabismologist to accurately determine the cause of the squint and to plan treatment.

Should we worry if a newborn seems to have a slight squint sometimes?

A newborn infant’s eyes may seem to wander occasionally. This is usually normal and the eyes become aligned by three months of age. If there is any doubt about the alignment of the eyes after three months of age, it is necessary to take the child for a full checkup.

One should not wait for three months, but should go to an ophthalmologist immediately:

If the child has a history of prematurity

If there is history of neonatal infection or difficult birth

If there is a white shiny reflex in the eye

If the squint is large angled and constant

If there is a family history of high refractive errors.

Do all squints need surgery?

As mentioned earlier, squints can occur due to various different reasons, and each patient’s treatment is different and aimed at treating the underlying cause of the squint.

If the squint is due to a misalignment of the muscles, then surgery is usually required to restore the balance. However, squint can occur due to refractive errors or other causes where surgery is not required.

These two children both have similar looking squints: 

The first child’s squint was corrected surgically but the second child only needed accurate glasses for her squint to be corrected.

Can glasses be used to correct squint?

As mentioned above, correct glasses may be all that is required to correct a squint.

If a child has high plus power (hypermetropia), the effort made to see clearly often precipitates a convergent squint.

This is known as refractive accommodative esotropia and is not at all uncommon.

Although bifocals and progressive lenses are commonly used to correct difficulty in near vision in patients above 40, sometimes, children may need to be prescribed bifocal or progressive lenses for the correction of squint. 

Although bifocals and progressive lenses are commonly used to correct difficulty in near vision in patients above 40, sometimes, children may need to be prescribed bifocal or progressive lenses for the correction of squint.

Is squint surgery purely cosmetic? Can squint lead to visual problems?

Although the first thing noticeable about a person with squint is the cosmetic defect, squint is far from being a purely cosmetic problem.

When the two eyes work together, they focus on a single object and the brain fuses the two similar images from the two eyes into one three-dimensional image. If the two eyes are not synchronized, the brain is faced with two dissimilar inputs from the two eyes. This leads to confusion and double vision. To combat this problem, the brain shuts off the image from the squinting eye and this can lead to permanent fall of vision of the squinting eye. Squint surgery, if performed early, aims at combating this problem to try to restore binocular single vision.

Is it true that squint may be due to an underlying systemic condition?

Squint may sometimes be the outward manifestation of serious neurological conditions. If the nerve supplying an eye muscle is paralysed due to any reason, a sudden onset squint may occur. This is why ophthalmologists sometimes refer patients with squint for a thorough neurological checkup.

Long standing uncontrolled diabetes leads to various eye problems. One such problem is a sudden onset squint due to ischaemic nerve damage. Various other systemic illnesses like myasthenia gravis may also lead to squint which is variable in nature.

Closed head injury following road traffic accidents may lead to damage to the VI cranial nerve leading to a squint.

In all situation where the squint is due to a systemic condition or due to trauma, it is necessary to treat the underlying cause first. Some of these squints will resolve with time and treatment of the cause.