Down Syndrome and the Eyes
Down syndrome occurs when a person had an extra copy of all or part of chromosome 21. This gives a person three copies of the chromosome rather than the usual two copies. Down syndrome is also called Trisomy 21. The extra copy of chromosome 21 leads to certain physical changes in children with Down syndrome.
Down syndrome occurs in approximately 1 in every 800 births. It is one of the most common chromosomal conditions that occurs in children. Children with Down syndrome are at an increased risk for eye conditions, most of which can be treated.
Common eye conditions found in children with Down syndrome include:
- Refractive errors (need for glasses) – Children with Down syndrome are more likely to need glasses than other children. This may be due to myopia (nearsightedness), hyperopia (farsightedness), and/or astigmatism. Refractive error may develop early in life or later on.
- Strabismus/misaligned eyes – Between 20% and 60% of individuals with Down syndrome have strabismus. Strabismus may be treated with glasses, patching and/or eye muscle surgery.
- Blepharitis (eyelid inflammation) – Children with Down syndrome have a higher rate of inflammation of the eyelids that can cause redness at the edge of the lids and crusting around the lashes. Treatment usually includes eyelid hygiene (warm compresses and eyelid cleaning).
- Tearing – Excessive tears or watering of the eyes may occur because the drainage system of the eye is blocked or narrow. In some patients, this may require surgical intervention.
- Cataracts – Children with Down syndrome have an increased risk of being born with cataracts or developing cataracts later in life. The cataracts may progress slowly. If cataracts are present, they should be monitored regularly. Some cataracts may require surgical treatment.
- Nystagmus – This is an involuntary “back-and-forth” movement or shaking of the eyes. It occurs in a higher percentage of children with Down syndrome. This usually does not affect vision, but some children may need to be treated if they turn their heads a large amount while focusing to slow down the shaking.
- Keratoconus – This is a cone-shaped distortion of the cornea (the front, clear window of the eye), which occurs more frequently in patients with Down syndrome. Keratoconus is usually diagnosed around puberty and should be monitored regularly. Blurred vision, corneal thinning or cloudiness of the cornea may result from keratoconus. Keratoconus is worsened by eye rubbing. Therefore, eye rubbing should be avoided.
- Glaucoma – There is an increased risk of infantile glaucoma (elevated pressure within the eye).
The American Academy of Pediatrics recommends that children with Down syndrome have an eye exam by 6 months of age.