Where it is
Two lateral ventricles in the hemispheres, the third ventricle in the midline between the thalami, and the fourth ventricle in front of the cerebellum, connected by the cerebral aqueduct.
What it does
The choroid plexus produces about 500 mL of cerebrospinal fluid (CSF) per day. CSF cushions the brain, removes waste and is reabsorbed into the venous system.
Clinical relevance
- Blocked CSF flow causes hydrocephalus: in infants an enlarging head and bulging fontanel; in adults signs of increased ICP.
- A ventriculoperitoneal (VP) shunt drains excess CSF into the abdomen.
- External ventricular drains monitor ICP and drain CSF.
Nursing focus
- For infants with a shunt, measure head circumference and report irritability, vomiting or a bulging fontanel (shunt malfunction).