Strabismus and lazy eye
All of the muscles in each eye must be coordinated by the brain for binocular vision to function
Squint
Strabismus is a visible misalignment of the eyes, with one eye turning in, out, up, down or at an oblique angle. Strabismus misalignment of the eyes can occur in some or all directions of gaze and can result in diplopia (double vision) or amylopia (lazy eye).
Early diagnosis of strabismus is essential in preventing irreversible vision loss later in life. Strabismus treatment aims to improve the alignment of the eyes and to correct the resulting vision loss (amblyopia). Amblyopia is regarded clinically as a 2-line difference from best corrected visual acuity in a structurally healthy eye.
Strabismus is one of the most common eye conditions affecting up to 5% of the Australian population. Prisms are used to measure the degree of the strabismus and double vision.
With normal vision, both eyes aim at the same spot. The brain then combines the two pictures into a single, three-dimensional image. This three-dimensional image gives us depth perception.
Good vision develops during childhood when both eyes have normal alignment. Strabismus may cause reduced vision, or amblyopia, in the misaligned eye.
Strabismic amblyopia occurs in approximately half of the children who have strabismus.
Amblyopia can be treated by patching or blurring the stronger eye to strengthen and improve vision in the weaker eye. If treatment is delayed, amblyopia may become permanent. The earlier amblyopia is treated, the better the result for vision. Family history can be relevant.
If one eye becomes favoured it can become dominant and suppress the effect of the other eye vision integrating in the brain .To stop confusion, the brain will sometimes ignore part of the image from one eye.
What are the signs and symptoms
Common signs can include closing one eye, clumsiness, an unusual head position,misaligned eyes , double or blurred vision and difficulty reading.
It is normal for a baby’s eyes to look misaligned for short periods of time up to the age of four months but full assesment is required.
Strabismus is especially common among children with disorders that may affect the brain, such as:
Cerebral palsy
Down syndrome
Hydrocephalus
Brain tumors
Prematurity
Treatment aims to improve the alignment of the eyes and to bring back, or protect, normal vision. Treatment can include glasses,prisms,patching or blurring of one eye, eye drops, eye muscle surgery or botulinum toxin which can alter effects of eye muscles and eye exercises.
Genetics and family history are relevant. If you or your spouse has strabismus, your children have a greater risk of developing strabismus as well.