Your eye works a lot like a camera. Light rays focus through the lens on the retina, a layer of light-sensitive cells at the back of the eye. Similar to photographic film, the retina allows the image to be "seen" by the brain.

A cataract is complete or partial opacification of lens material (nucleus, cortex, or capsule). The loss of transparency may be so mild that vision is barely affected, or it can be so severe that no shapes or movements are seen--only light and dark. Eyeglasses or contact lenses can in some cases correct slight refractive errors caused by early cataracts, but they cannot sharpen your vision if a severe cataract is present.

Cataracts that occur in childten are different than cataracts which occur as an aging phenomenon in adults. As such they require a different evaluation, and different modalities of management, taking into consideration the different etiologies and the development of the visual system.In visually immature children, the age at onset and the degree of maturation of the visula system are additional considerations. The first six months of life are a period of critical visual development in infants. During this time, a clear focused retinal image is required to permit normal development of the visual system. If this is not present, either one or both eyes will not achieve it's fullpotential for viual acuity due to the development of irreversible deprivation amblyopia. The development of amblyopia continues to be a problem until maturity of the visual system is reached, roughly around the age of 8 years. Early diagnosis and prompt treatment are critical factors in determining the visual outcome in infants and children with cataracts.

There are many causes of congenital and childhood cataracts. Certain diseases, both metabolic and infectious, can cause the condition, and they can also be inherited in an autosomal dominant or recessive pattern. Cataracts can also be associated with specific genetic syndomes. However, in many cases, there is no identifiable cause.

A complete history and thorough eye exam can help establish the type and etiology of the cataract. In some cases laboratory testing and/or referrals to other specialists, such as genetists or rheumatologists, will be recommended. (See Tables I-III)

Treatment for cataract in infants and varies depending on the nature of each patient's condition. Surgery is usually recommended very early in life, but many factors affect this decision, including the infant's health and whether there is a cataract in one or both eyes. If only one eye is affected by cataract, the infant's visual system can develop abnormally, and, if left untreated, serious vision problems and even vision loss can result. Therefore, removal is usually recommended within the first 4-8 weeks of life. In bilateral cases, surgery may be able to be delayed, however often the more effected eye is done first, followed 2-3 weeks later by the other eye.

Surgery in infants requires general anesthesia and is done in an operating room under sterile conditions. An incision is made in the cornea or sclera of the eye, and an opening is created in the anterior capsule allowing the removal of the lens nucleus and cortex using a specially designed aspiration-cutting instrument. In young children a part of the posterior capsule will also be removed to help prevent further opacification, often called a "secondary membrane". Even with removal of the posterior capsule, in some cases further laser or surgical intervention will be required.

Post operatively, a child will require a combination of antibiotic, steroid and dilating drops for several weeks. Your surgeon will give you explicit instructions. A shield will also be used to protect the eye, for about a week.

Usually, strong eyeglasses or contact lenses are prescribed for infants after surgery who are aphakic (without a lens). For babies over 6months of age, an artificial intraocular lens (IOL) may be recommended instead to replace the eye's natural lens. The ophthalmologist can recommend which procedure and optical correction is best for your child. Many factors are involved in optical correction including focusing light on the retina, providing the ability to focus at both distance and near, protection from UV light, and the ability to change with a child's growth. Currently, there is no perfect method, and frequently a combination of intraocular lens or contact lens with glasses and a bifocal will be necessary.

After surgery, children must be followed closely, complications such as infection and retinal detachment are rare, but can be sight threatening when they occur. Glaucoma can occur at any time, and may require drops or further surgery, rates as high as 25% have been reported in eyes that have undergone cataract extraction. Strabismus (misalignment of the eyes) and amblyopia (weaker vision in one eye) are common in eyes that have cataracts, even once the lens has been removed. Occlusion therapy, such as patching, may be required until the child reaches visual maturity. The management of a child with cataracts requires a commitment from both the surgeon and the family, that extends from the timing of surgery to the lengthy rehabilition stage and beyond.

9/25/09