The brain consists of elaborate, interconnected fluid-filled cavities called ventricles.
They are filled withcerebrospinal fluid (CSF)produced by the choroid plexus.
The third ventricle makes up the central part of the brain and facilitates communication between other ventricles.
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The roof is made up of the choroid plexus where CSF is produced by ependymal cells.
Location
The third ventricle is a midline structure.
It is found between the cerebral hemispheres.
The third ventricle is situated between the right and the left thalamus.
Ventriculomegaly can be a benign finding, particularly in isolated cases.
Colloid Cysts
Colloid cysts are benign, slow-growing lesions of the third ventricle.
They can present as incidental findings on imaging or with symptoms of obstructive hydrocephalus.
The causes of colloid cysts are unknown, but they seem to run in families.
Researchers have pointed to a potential association between familial colloid cysts and congenital inguinal hernia.
Schizophrenia
One study found that people withschizophreniaand their healthy siblings have larger third ventricles.
The findings suggest that there could be related genetic defects that produce a susceptibility to the mental health condition.
Function
The third ventricle is the main site for CSF production.
Tests
Ventriculomegaly can be detected through prenatal tests or after the baby is born.
2006;117(5):e928-e931.
2000;157(3):416-421. doi:10.1176/appi.ajp.157.3.416
American Association of Neurological Surgeons.Adult-onset hydrocephalus.
