Some babies are born with or acquire opaque areas in the lens, a normally transparent structure that helps the eye focus light and form images. These defects, known as cataracts, may affect either one eye (unilateral) or both eyes (bilateral). Detected early in infancy, most cataracts can be surgically corrected without lasting visual impairments. Screening for them is therefore routine during well-baby medical checkups. Although most children with cataracts are otherwise healthy, this condition may, in rare instances, signal a serious but treatable underlying disease.
WHAT CAUSES CATARACTS?
A wide array of conditions can precipitate cataracts, but generally they belong to either of two categories: congenital or acquired. Cataracts can be acquired as a result of an eye injury or as a side effect to treatment with certain drugs or radiation. Childhood diseases such as rheumatoid arthritis can also be associated with cataracts. Children who have these kinds of cataracts tend to have better long-term visual function than infants born with the defect.
Congenital cataracts, which emerge before the first birthday, often run in families. Certain other hereditary visual disorders such as glaucoma (in which abnormal pressure builds up in the eye) can give rise to cataracts.
Inherited metabolic diseases also may promote cataract formation. In addition to diabetes, inborn deficiencies of enzymes needed to break down the sugar found in milk (lactose) can lead to accumulation of another sugar called galactitol, which clouds the lens. These metabolic deficiencies are very rare.
For reasons not as yet thoroughly understood, cataracts also are more likely in babies with Down's syndrome or other chromosomal disorders. Finally, premature infants—especially those exposed to either infections in the womb or serious injury during birth—seem to be more prone to cataract formation than full-term babies.
WHEN SHOULD I SUSPECT CATARACTS?
Precise recognition of cataracts is a matter best left in the hands of an experienced physician. One or both eyes may look cloudy, with the opacities taking the shape of oil droplets or snowflakes.
Other signs are more indirect. Cataracts cause blurred and double vision, which can make body movements clumsy and delay achievement of certain developmental milestones.
IS MEDICAL ATTENTION NECESSARY?
Yes. Cataracts usually can be corrected, provided that they are detected and repaired early. Then, with the right corrective contact lenses and other optical therapies, the child should be able to see normally.
Left untreated, however, cataracts in both eyes can touch off squinting or jerky eye movements that rob the infant of the visual stimulation needed for normal development. Eyesight can become permanently damaged in such cases.
HOW CAN THE PEDIATRICIAN TELL THAT MY CHILD HAS CATARACTS?
To screen for cataracts, physicians test a special visual reflex in the first six weeks of life. Using the hand-held instrument called an ophthalmoscope, they aim a gentle red light beam across the pupil of each eye and look for a special visual response. Absence of the so-called red-light reflex helps the physicians to diagnose cataracts. If cataracts are found, pediatricians usually refer the patient to an eye specialist (ophthalmologist) for further evaluation and treatment.
Children with metabolic or genetic disorders that make them more vulnerable to the development of cataracts should have regular eye checkups. Many pediatricians can perform such checkups in their offices.
WHAT TREATMENTS ARE AVAILABLE?
Because most cataracts tend to progress and expand, surgical removal usually is recommended soon after they are detected. The present standard of care includes surgical correction of a unilateral cataract as early as one or two months of age. Current operative techniques usually are successful, producing little if any scarring and doing away with the need for second operations. No procedure is without side effects, however. For instance, one or two of every ten patients undergoing surgical repair of congenital cataracts go on to suffer glaucoma.
Postoperative therapy involves using extended- or daily-wear contact lenses or special glasses. If only one eye has cataracts, the better eye is covered (patched) for progressively longer periods each day. This measure is necessary to strengthen the affected eye and prevent further visual impairment.
Thanks to soft and gas-permeable lenses, contacts can be easily fitted, even to an infant's tiny eyes. In some cases, more conservative therapies may be appropriate. For some partial cataracts, eye drops that dilate the pupil, together with patching of the better eye, do the trick.
GETTING HELP
Call your doctor if:
• Either one or both of a baby's eyes seem cloudy or lacking in clarity, especially if the baby was premature or there is a history of cataracts in your family
• You suspect that focusing and other visual skills are lacking or slow to develop
