Squint is also known as strabismus. The eye is turned in a different direction to the other. This inclination of the eye appears because of an incorrect balance of the eye muscles, which can be traced to various different causes. A lot of people think that in most of the cases children are affected by squint, but there are also older patients with squint. At Clinica London our Paediatric Ophthalmic Surgeons look after children and adults with squints (strabismus).
Types of strabismus
Exotropia: This is where one eye diverges compared with the other, and can be associated with poor vision in one eye, or worsening of a childhood divergent squint. In these childhood exotropias, control of the squint can become more difficult with age, and surgery as an adult is possible.
Esotropia: This is where one eye converges relative to the other. It can be a long-standing childhood squint or acquired in adulthood. In both cases, treatment is usually possible.
Consecutive strabismus: This is where an eye drifts out again after strabismus surgery as a child. As the patient gets older, especially if one eye is amblyopic (lazy) and does not fix, then the eye cannot always stay in the position it was placed. So the eye subsequently slowly drifts out.
Restrictive strabismus: This is where one muscle or more does not move effectively as it is scarred or enlarged. For instance, after trauma when it is entrapped in a small orbital fracture, has a direct scar, where there is enlarged muscles in thyroid eye disease or after some ENT surgery including orbital decompression.
Nerve palsy: This is 3rd, 4th or 6th nerve palsy which can give a combination of squint, double vision (either vertical or horizontal) and eyelid ptosis or small compensatory head posture.
Myopathy: This is where the muscles are weak and hardly move. They often have both eyelids drooping (ptosis) so the emphasis is mainly on the eyelid surgery as they rarely get double vision.