الفهرس 
Anatomy of the ventricular systemOnly 14 pages are availabe for public view
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Abstract
Hydrocephalus is an imbalance of CSF formation and absorption of sufficient magnitude to produce a net accumulation of CSF within the cerebral ventricles.
Hypothetically, the condition may arise in three ways:
• Obstruction of CSF pathways
• CSF over secretion
• Impaired venous drainage
The incidence of infantile hydrocephalus is about 3 to 4 per 1000 live births, this does not reflect the incidence of acquired hydrocephalus. Adult hydrocephalus represents approximately 40% of the total cases of hydrocephalus.
The clinical diagnosis of infantile hydrocephalus is sometimes obvious at birth. In advanced cases there is enormously large head, small and frail body, significant craniofacial disproportion with expansion of the dome. The scalp is often shiny and glistening with distended and bulging veins. The anterior fontanelle is typically enlarged. Other signs of increased intra cranial pressure may be present.
It is apparent that CT scanning is the diagnostic procedure of choice for evaluating patients with known or suspected hydrocephalus. Also, cranial sonography is a very good diagnostic tool, especially in cases with opened anterior fontanelle.
Hydrocephalus should be treated if it is progressive even if it is asymptomatic, and it should be treated if it is symptomatic, even if the symptoms are subtle or atypical. Treatment is contraindicated if hydrocephalus is asymptomatic and non progressive.
Ventriculoperitoneal shunts are presently the mainstay of hydrocephalus treatment because of their ease of insersion and reliable long-term function. Other types of extracranial shunts as ventriculoatrial, ventriculopleural and lumboperitoneal shunts are usually reserved for circumstances in which ventriculoperitoneal shunts are contraindicated.
Despite their ability to control the symptoms and signs of hydrocephalus, the shunts are foreign bodies associated with several potential complications, some occur immediately, while other occur over the long term. Shunt obstruction and infection are the most common complications.
The recent studies revealed that nearly half of all shunt placements were for revision, and there are a low but real percentage of cases in which death and neurological impairment are related to shunt surgery. This clearly means that the shunt systems and the techniques in current use involve many problems that have yet to be solved.
Endoscopic third ventriculostomy is a procedure in which a tiny perforation is made in the floor of the third ventricle, thus allowing movement of the cerebrospinal fluid out of the blocked ventricle into the subarachnoid space. Because of high rate of shunt malfunction and the severity of some complications in cases of aqueduct stenosis, endoscopic third ventriculostomy must not be considered as an alternative treatment for these patients but as the first choice at least in a selected group.