Below is a short list of known complications that can lead to hydrocephalus requiring shunting. Diagnoses Description Incidence Congenital hydrocephalus A wide range of genetic abnormalities that could lead to hydrocephalus at birth. 0.04–0.08% Tumor A number of different tumors can lead to CSF blockage if they are located in certain areas. Some of these areas include the lateral or third ventricles, the posterior fossa, and intraspinal tumors. The tumors may be malignant or benign. Unknown Post-haemorrhagic hydrocephalus Bleeding into the ventricles of the brain, especially in infancy, can lead to blockage of CSF drainage and cause hydrocephalus. Spina bifida Specifically spina bifida myelomeningocele can cause the development of hydrocephalus because the cerebellum will block the flow of CSF in a development of Chiari Malformation II. .125% Congenital aqueductal stenosis A genetic disorder which can cause deformations of the nervous system. The defect is commonly associated with mental retardation, abducted thumbs and spastic paraplegia. .003% Craniosynostosis Craniosynostosis occurs when the sutures of the skull close too early. The result of multiple sutures fusing before the brain stops growing is an increase in ICP leading to hydrocephalus. 0.05% Post-meningitic hydrocephalus The inflammation and scarring caused by meningitis can inhibit CSF absorption. Dandy–Walker syndrome Patients usually present with a cystic deformity of the fourth ventricle, hypoplasia of the cerebellar vermis, and an enlarged posterior fossa. The condition is a genetically heritable disease. 0.003% Arachnoid cyst A defect caused when CSF forms a collection that is trapped in the arachnoid membranes. The resulting cyst can then block the normal flow of CSF from the brain resulting in hydrocephalus as well as other defects. The most common locations for an arachnoid cyst are the middle fossa and the posterior fossa. The most common symptoms are nausea and vertigo. 0.05% Idiopathic intracranial hypertension A rare neurological disorder affecting approximately 1 in 100,000 people, most of whom are women of child-bearing age. IIH results in a raised intracranial pressure and can lead to permanent loss of vision. Normal pressure hydrocephalus, also known as Hakim-Adams syndrome Excess cerebrospinal fluid (CSF) occurs in the ventricles, and with normal or slightly elevated cerebrospinal fluid pressure
Cerebral shunt
Lumbar–peritoneal shunt
Cardiac shunt
Sano shunt
Cerebrospinal fluid diversion
Ventriculotomy 
Ventriculostomy
Atriocaval shunt