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= Childhood cataract = From Wikipedia, the free encyclopedia

Childhood cataract is cataract that occurs at birth or in childhood. It may be congenital or acquired. The use of the category “acquired” or “juvenile” is ambiguous in that it can refer to the time of onset or cause of the disease. An acquired or juvenile cataract can indicate one that develops spontaneously due to an external factor (i.e. a mutation in a gene) regardless of time of onset. However, it can also refer to onset that takes place after infancy regardless of cause.

Diagnosis
It is vital that the diagnosis of a cataract is made as early as possible in order to prevent abnormal development of visual acuity.

Prior to the diagnosis of childhood cataract, the physician must acquire both a detailed family history and a detailed medical history. The family history must include a prenatal history; and information regarding maternal drug use and a birth history must be provided.

Newborns are required to take a physical and vision examination 72 hours after delivery. The same examination is due for an update when the newborn is 6-8 weeks old. During the vision examination the newborns are subject to a test on their responses to different appearances and movements. To test for the presence of a cataract, the baby is given the red reflex test.

The development of a cataract may not occur until later in the child’s life; therefore, it is important that routine eye examinations are conducted on a yearly basis.

Epidemiology
Childhood cataracts affect around 200,000 children worldwide. The incidence of childhood cataract occurs in every 1-15 per 10,000 children. The incidence of acquiring a cataract in developed countries is only 1-3/10,000 births whereas the prevalence in developing countries is significantly higher due to risk of and exposure to other diseases and external factors.

Etiology
There is a multitude of underlying causes of childhood cataracts in the industrial world. Most cases of childhood cataracts are idiopathic. Other possible causes include, but are not limited to: trauma to the eye, diabetes, use of steroids, radiation therapy, and complications from other eye diseases or treatment of other childhood diseases.

Developed countries are unable to identify the fundamental cause of childhood cataracts in all unilateral cases and 50% of bilateral cases. Within the 50% of bilateral cases, roughly 20% pertain to individuals with a family history of an autosomal dominant cataract. The remaining 30% of bilateral cases is caused by a genetic abnormality (i.e. chromosomal) in conjunction with other ocular disorders.

Numerous studies have been conducted in developing countries that link infants diagnosed with an infantile cataract with a pregnant mother who had contracted rubella.

Treatment
The procedure for performing a cataract surgery on a child differs greatly from one conducted on an adult. The surgery requires the use of a general anaesthetic and is conducted using one of two commonly practiced procedures: Lensectomy or Extra-capsular Cataract Extraction (ECCE).

Difficulties in surgical correction of childhood cataracts are more pronounced in developing countries. This is due to the fact that they lack access to the proper medical equipment and the expertise required to perform surgery on a paediatric cataract. For example would be that children have not developed a hard lens nucleus, thus extra precision and care must be exercised when performing the surgery.