What is squint and how can it be treated?

Mr Nadeem Ali MA MB BHChir MRCOphth FRCSEd(Ophth) is a Consultant at Moorfields Eye Hospital specialising in adult squint surgery. He helps patients from across the UK and from around the world with squint, strabismus, lazy eye and double vision.


Squint (or ‘strabismus’) is a medical condition affecting the eyes. When a person has a squint, one of their eyes does not point in the right direction.  For example, the squinting eye could be turned inwards towards the nose, or outwards, or even upwards or downwards. The squint may be there all the time, or only some of the time.

The person may be able to control the squint or may have no control over it at all. It is also possible for it to affect only one eye, or switch between the two eyes.

Often a squint occurs in a lazy eye - which is an eye with poor vision from childhood, however squints can also occur in healthy eyes with good vision. They can come on in childhood, or appear in adult life. 

There are many different types of squint, which have different terms according to how they present. Some of the most common are ‘extropia’ (where the eye turns outwards) and ‘esotropia’ (where the eye turns inwards).


Some squints are really too small to be noticed by other people, and treating them may not always be the best thing to do. However, for those who find their squint to be affecting their daily life there are a number of treatment options available.



For a small number of people, the squint can be helped by glasses alone. This is normally the case for people who are long-sighted in whom glasses relax their eyes and allow the eyes to go straight.



Botulinum toxin injections (botox)

Not many people know that long before Botox was used for cosmetic purposes, it was used for treating squint. By injecting botulinum toxin into one of the eye muscles, you can cause a change in the position of the eye. This can lead to an improvement in a squint. The injection is done with the patient awake, sitting in a chair, with local anaesthetic drops and takes only a few minutes. The problem with botulinum toxin for treating squint is that it is not a permanent treatment. The effect only lasts about 3-4 months and then the treatment has to be repeated, again and again. It is a good treatment for people who can’t undergo surgery for whatever reason, but for most people who want a long-term solution, surgery is a better option (see below).


Eye exercise

Many patients ask about eye exercises to cure squint. There are several websites and some doctors that claim that you can cure squints by following a plan of exercises for your eye muscles. It is safe to say that eye exercises probably don’t do any harm, however there is very little evidence to show that they provide effective treatment. There are one or two exceptions to this, where exercises do make a difference, but most people will find exercises don’t really improve their squint.



During squint surgery, one or more of the eye muscles are altered via the white membranes on the surface of the eye. Muscles can be repositioned forwards, backwards, shortened or moved to a different point of attachment on the eyeball, and once in their new position are stitched in place (using dissolvable sutures) until firmly reattached.


Most operations can be done in less than an hour under a general anaesthetic, however local anaesthetic can also be an option.


If you fulfil the following criteria you are eligible to have squint surgery:

  • You have a squint that affects your daily life. 

  • Your squint is large enough to be noticeable. 

  • Your eye tissues are healthy enough to undergo surgery.

Previous surgery does not affect your eligibility to have further surgery, and age is not an influencing factor.

Squint surgery is one of the safest types of eye surgery, largely because it doesn’t involve entering the eyeball at all, so the risk to the important structures inside the eye is very low. However, it is advisable to discuss any risks that may apply to your personal circumstances with your surgeon before undergoing the surgery.

Post-surgery, the eye will normally take around 2 months to recover and reach its desirable position.



Nadeem Ali is a Consultant Adult Squint Surgeon at the world famous Moorfields Eye Hospital in London, and one of just a few surgeons in the world who are 100% focused on squint surgery in adults. Patients come to his private clinic from across the UK and the globe to benefit from his specialist expertise.


At Moorfields Eye Hospital Mr Ali is in charge of the continuous audit for squint surgery - monitoring the safety of all squint operations performed in the Trust. He also runs outreach clinics at St George’s Hospital and is proud to have received an NHS Hero award for patient care. 

Mr Ali trains Fellows from the UK and abroad at advanced level in squint surgery, and is in charge of the Ophthalmology course for medical students at St George’s Medical School, University of London, where he is an Honorary Senior Lecturer.

To make an enquiry regarding Mr Ali's private squint correction service at the Moorfields Eye Hospital, use the following contact details:

Email: info@londonsquintclinic.com
Telephone: 0207 566 2604

Or Visit www.londonsquintclinic.com to learn more.