Squint & Orthoptics
What is squint?
Squint is misalignment of the eyes such that the right and left eyes are pointed in different directions. Though it is a common condition among younger populations, affecting 2 to 4 percent of children, it may also appear later in life.
The misalignment may be permanent or it may be temporary, occurring occasionally. The deviation may be in any direction: inward, outward, upward or downward. If the child is not treated at the appropriate time, a condition called amblyopia occurs, which eventually leads to permanent loss of vision. Squint may be caused by any of the following:
- Weakened muscles or abnormal nerve impulses to the eye muscles
- Blurred or poor vision due to cataract, corneal scars, glaucoma, refractive errors, optic nerve disease, retinal disease, tumors of the eye etc.,
- Pathology inside the eye, such as cataract
Signs and Symptoms
The primary sign of squint is an eye that is not straight. Sometimes, a youngster will squint or close one eye in bright sunlight. Faulty depth perception may be present. Some children turn their faces or tilt their heads in a specific direction in order to use their eyes together. The child sometimes experiences double vision or confusion.
Parents often get the false impression that a child may "outgrow" the problem. If a child's two eyes are pointed in different directions, examination by an ophthalmologist is necessary to determine the cause and to begin treatment.
The goals of treatment are to preserve vision, straighten the eyes and to restore binocular vision. Treatment of squint depends on the exact cause of the misaligned eyes. It can be directed towards unbalanced muscles or other conditions which are causing the eyes to point in two different directions. After a complete eye examination, including a detailed study of the inner parts of the eye, an ophthalmologist can recommend appropriate optical, medical or surgical therapy.
Non-surgical treatment - spectacles
Some squints are caused by refractive errors. In such cases, squint can be corrected by prescribing proper spectacles.
Most patients require surgical correction. Surgery is done under general anaesthesia in children and under local anaesthesia in cooperating adults. To undergo general anaesthesia the child should be free from acute illness. Parents should inform the doctor if the child is having any systemic problems such as cardiac disease or epilepsy.
- Routine investigations before surgery include a blood test and an X-ray of the chest.
- Surgery is done either on both eyes simultaneously or on one at a time. Surgery is done on eye muscles situated outside the eyeball. The surgery is done on the white portion of the eyeball. The eyeball is not opened.
- The principle of surgery is to weaken the stronger muscle and strengthen the weaker muscle. Either one or several muscles may be operated upon, depending on the type and severity of squint.
- Eye is bandaged for one day after surgery.
- After surgery, eye drops are to be used for one month.
- Oral medication is not required except in a few cases.
- Hospital stay is only for two days
- First follow-up visit will be one month after surgery.
- If amblyopia is present frequent follow-up appointments for a longer duration are required.
- It is unnecessary to restrain the normal activities of the child.
Treatment does not stop with surgery. Glasses may have to be continued to maintain clarity of vision. Patching therapy may be needed to be continued for some time after the surgery.