Squint surgery

What is a squint?

A squint is a condition in which one eye is out of alignment i.e. one eye looks straight ahead whilst the other eye turns inwards, outwards, up or down. Squints may be constant (apparent at all times) or intermittent (only apparent at certain times). The majority of squints appear in the first three years of life, but occasionally a squint may develop later.

How does a squint affect eyesight?

Children DO NOT grow out of true squints. It is therefore essential they are
examined by an eye specialist to assess the squint and the eyesight. When a squint is present in childhood the child may stop using the squinting eye. This may lead to poor sight in that eye. This is commonly called a “lazy eye.”

Before surgery


After surgery


“Many thanks for the successful operation on Zac, it’s a fantastic improvement and we can tell how much it has helped him. He can see what he’s doing now. Kind regards Richard, Clare and Zac”

Ingoing Squint From Birth

An ingoing squint that develops before 6 months may be congenital esotropia. It may be associated with one eye moving above the other (dissociated vertical deviation) and wobbly eyes (latent nystagmus).

Evidence suggests that surgery should be performed between 12 and 24 months of age in order to attempt to develop 3 dimensional (3D) vision. This may be botulinum toxin injection with or without conventional squint surgery. Often 2-3 operations are required particularly with early surgery. Upgoing squint surgery may be needed.

Risks Of Squint Surgery

In squint surgery a muscle that moves the eye needs to have its function altered. This means moving it to another position or shortening it to strengthen it. The needle is placed into the sclera which is a thin layer of the eye.

80% of operations need to be performed only once. There is a chance of undercorrection and overcorrection in 20% of cases and repeat surgery may be necessary.
The eyes will be red for 3 months and drops will be necessary for 1 month.

Uncommon problems

  • The muscle may not stick to the eye and a repeat operation may have to be performed very soon afterwards.
  • A 1 in 6,000 chance of the needle going into the eye. Poor vision may result due to infection but not always.
  • An allergy to stitches may occur which will result in small areas of inflammation.


We wanted to ensure that our 8 year old daughter received the best possible care for her squint and we certainly received this from Mr Reddy and his team at Moorfields. From our first visit we were put at ease by the kindness and professionalism of Mr Reddy. Our daughter eventually needed squint surgery which went extremely well – we are now 4 weeks post surgery and her 3D vision has been restored, eyes are perfectly aligned and recovery has been minimal. We are delighted with the results and would wholeheartedly recommend Mr Reddy and team.