(See also Cataract in adults.)
Congenital cataracts have many causes. They may be inherited (multiple genetic or chromosomal disorders), related to disorders of metabolism (such as galactosemia), or caused by infections contracted while in the womb (such as rubella) or by another disease of the mother during pregnancy.
Congenital cataracts may affect only one or both eyes. They may not be noticed unless a complete eye examination is done at birth. As with other cataracts, the clouding of the lens sometimes blocks vision. Infants with cataracts should always be evaluated by a medical doctor who specializes in the evaluation and treatment of all types of eye disorders (ophthalmologist).
Some cataracts cover only part of the lens (partial cataracts), and cloudiness begins during the first 10 years of life. Vision is better in eyes that have partial cataracts.
If necessary, ophthalmologists remove the whole lens containing the cataract through a small incision in the eye. Sometimes, like in adult cataract surgery, doctors implant a plastic or silicone lens (intraocular lens) at the same time. However, for many infants, doctors wait until the child is older, usually about age 2 years, to implant the lens. Until then, the child wears a hard contact lens to correct vision.
After a cataract is removed from one eye, the quality of the image in the treated eye is still poorer than that of the other eye (assuming the other eye is normal). Because the better eye is preferred, the brain suppresses the poorer-quality image, and amblyopia (decrease in vision that occurs because the brain ignores the image received from an eye) develops. If doctors cannot correct the vision sufficiently in the surgically treated eye, they often force the child to use the treated eye by putting a patch over the better eye (patching) or using eye drops to blur the vision in the better eye. Patching or using eye drops in the better eye helps the treated eye develop normal sight.
After cataracts are removed from both eyes, children who had image quality that was similar in both eyes more frequently develop equal vision in both eyes.
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
Children's Eye Foundation of AAPOS: Practical information about prevention, detection, research, and education to protect the vision of children