Overview
How the Shunt Changes CSF Dynamics
Cerebrospinal fluid (CSF) is continuously produced within the ventricles, circulates through the ventricular system and subarachnoid space, and is then absorbed.
Cerebrospinal fluid (CSF) is continuously produced within the ventricles, circulates through the ventricular system and subarachnoid space, and is then absorbed. Hydrocephalus develops when CSF flow is blocked or absorption is inadequate. Ventricular enlargement then raises intracranial pressure and can injure brain tissue. A ventriculoperitoneal (VP) shunt provides an alternate drainage route. A catheter in a lateral ventricle carries CSF to a one-way pressure- or flow-regulating valve, and distal tubing delivers it to the peritoneal cavity for absorption. The valve limits, but does not eliminate, the risk of draining too much or too little CSF. The shunt treats the consequences of abnormal CSF dynamics; it does not cure the underlying hydrocephalus. The patient therefore remains dependent on the system and requires ongoing surveillance for obstruction, infection, overdrainage, hardware failure, and recurrence of hydrocephalus symptoms. A previously stable patient who develops a new compatible symptom is not simply experiencing a routine fluctuation in a chronic condition.
