Definition:

Congenital hydrocephalus (HYC) is a common birth defect in the circulation of the cerebrospinal fluid (CSF). It is characterized by ventricular dilatation. Although commonly considered a single disorder, hydrocephalus is a collection of a heterogeneous complex and multifactorial disorders. It may occur alone (non-syndromic) or as part of a syndrome with other anomalies. Almost 50% of all cases of hydrocephalus are congenital and these are usually associated with adverse neurological outcome. It is probably the consequence of abnormal brain development. Genetic factors are involved in the pathogenesis of this disease. Molecular genetic studies have revealed that the responsible gene for X-linked human congenital hydrocephalus is encoding for L1CAM. Although the recurrence risk for congenital hydrocephalus excluding X-linked hydrocephalus is low, recently, a few genes for autosomal recessive congenital hydrocephalus have been identified. Besides genetic factors, many other factors influence the development of congenital hydrocephalus, such as congenital malformations, intracerebral hemorrhage, maternal alcohol use, infection, and X-ray radiation during pregnancy.