Squint (Strabismus): Causes,
Symptoms & Best Treatment Options
Under normal conditions, both our eyes work in perfect coordination, aligning in the same direction to focus on a single object. This alignment allows the brain to merge the visual input from both eyes into one clear image.
However, in some children, right from birth, this coordination is disrupted. Their eyes fail to align, leading to a condition known as squint or strabismus. When the brain receives different images from each eye, it may suppress the input from the weaker eye to avoid confusion. But if the brain starts processing both sets of images simultaneously, it can result in double vision.
Though squint commonly affects children, it can also develop later in life due to trauma, injury to the eye, or other underlying health conditions. If left untreated, it may lead to permanent vision problems.
What is a Squint?
A squint, also known as strabismus or crossed eyes, is a condition where the eyes are misaligned. Instead of pointing in the same direction, one eye may turn inward, outward, upward, or downward, disrupting normal binocular vision.
This misalignment typically results from poor control over the eye muscles due to faulty signals from the brain. Despite being concerning, squint is usually treatable, and in many cases, it can be corrected completely with proper intervention.
Types of Squint
Based on the direction in which the affected eye turns, squint can be classified into several types:
- Esotropia: Inward turning of the eye
- Exotropia: Outward turning of the eye
- Hypertropia: Upward deviation of the eye
- Hypotropia: Downward deviation of the eye

What Causes a Squint?
While many cases of squint are congenital (present from birth), it can also result from various other causes:
- Congenital Developmental Issues
Improper development of eye muscles, nerves, or brain areas responsible for vision during pregnancy can cause misalignment in newborns. - Genetic Factors
Family history of strabismus increases the likelihood of developing it in early childhood. - Eye Injuries or Trauma
Any damage to the brain, optic nerves, or retina due to an accident can lead to a squint. - Refractive Errors
Vision problems like nearsightedness (myopia), farsightedness (hyperopia), or astigmatism may contribute to strabismus. - Viral Infections
Certain infections such as measles, meningitis, or viral fever may affect the neurological system and contribute to this condition. - Other Medical Conditions
Neurological disorders, brain tumors, stroke, diabetes, and cerebral palsy can also increase the risk of developing a squint.
Symptoms of Squint
The most prominent sign of a squint is the inability of both eyes to focus on the same object. Other symptoms may include:
- Blurred or reduced vision
- Double vision (diplopia)
- Poor depth perception
- Eye strain or headaches
These symptoms may be persistent or may appear more prominently when the individual is tired or unwell.
Diagnosis of Squint
To accurately diagnose squint, the following tests are typically used:
- Corneal Light Reflex Test: Assesses eye alignment and determines the type and extent of squint.
- Visual Acuity Test: Measures the clarity of vision to check if it’s affected by the misalignment.
- Neurological Examination: If additional symptoms are present, brain and nerve tests (like MRI or CT scans) may be conducted to find any underlying neurological cause.

Treatment Options
Early detection greatly improves the chances of successful treatment. While treatment can be initiated at any age, intervention before the age of six is often the most effective.
Here are some common approaches:
1. Eye Exercises (Vision Therapy)
Special eye exercises help strengthen the eye muscles and improve coordination. These can be done using special devices in clinics (like a synoptophore) or at home.
Pencil Push-Up Exercise – A simple and effective method:
- Hold a pencil at arm’s length between the eyes.
- Slowly bring it towards the nose, maintaining a single image.
- Stop when the image splits and repeat.
- Perform these 20 times daily for up to 12 weeks.
2. Glasses or Contact Lenses
If squint is caused by a refractive error, corrective lenses can be very effective. In minor cases, prism lenses may also be recommended to help align the eyes.
3. Eye Patching
Covering the stronger eye with a patch encourages the weaker eye to function better, thereby improving vision in the affected eye.
4. Botulinum Toxin Injections (Botox)
Botox can be injected into the eye muscles to temporarily weaken them, helping realign the eyes. This is especially useful when the underlying cause is uncertain or surgery isn’t an option.
5. Surgery
When non-surgical treatments fail, surgical intervention may be needed to adjust the muscles controlling the eye. Surgery can restore alignment and improve binocular vision. Sometimes, surgery on both eyes is required for best results.
Risks of Not Treating Squint
If left untreated, squint can lead to a condition called amblyopia or “lazy eye,” where the brain suppresses the vision from one eye. Over time, this can cause permanent vision loss in the affected eye.
Even after successful treatment in childhood, squint can reappear in adulthood, potentially causing double vision due to the brain’s inability to ignore either eye’s input at that stage.
In severe cases, untreated squint can eventually lead to total loss of vision in the misaligned eye.
Conclusion
Squint is more than just a cosmetic concern, it’s a serious visual condition that can impair vision and quality of life if not addressed promptly. Fortunately, with timely diagnosis and the right treatment approach, full recovery is often possible. If you or your child is showing signs of a squint, consult an eye specialist without delay.