The lateral ventricles are paired CSF-filled spaces in the cerebrum and part of the ventricular system of the brain. They are larger than the third or fourth ventricles, but can be asymmetrical. Each has five divisions, including three horns that project into the lobe after which they are named:
- anterior/frontal horn
- inferior/temporal horn
- posterior/occipital horn
- bilaterally well developed in only 12% of subjects
- may be absent, poorly developed, asymmetrical
CSF is produced in the choroid plexus located along the lateral walls of the lateral ventricles related to the choroid fissure and exits along the interventricular foramen (of Monro) into the third ventricle. The central part of the lateral ventricle is called the cella media. The posterior confluence of the occipital and temporal horns is called the trigone or atrium of the ventricles.
- coarctation of frontal horn or body
- aplasia or hypoplasia of posterior horn
- asymmetry of lateral ventricle
- cavum septum pellucidum
- cavum septum pellucidum et vergae
- cavum veli interpositi
The volume of the lateral ventricles is known to increase with age due to cerebral involution. They may also be enlarged in a number of neurological conditions (e.g. schizophrenia and bipolar disorder) or pathologically enlarged as part of hydrocephalus.