Cavum septum pellucidum

Cavum septum pellucidum (CSP) describes a septum pellucidum that has a separation between its two leaflets (septal laminae). This cavity contains cerebrospinal fluid (CSF) that filters from the ventricles through the septal laminae .

CSP is bounded anteriorly by the genu of the corpus callosum; superiorly by the body of the corpus callosum; posteriorly by the anterior limb and pillars of the fornix; inferiorly by the anterior commissure and the rostrum of the corpus callosum; and laterally by the leaflets of the septum pellucidum .

The most common type of CSP is noncommunicating, that is, it does not connect to the brain's ventricular system. Because of this lack of communication, the erstwhile term for CSP, the "fifth ventricle," is not anatomically correct and its use has fallen out of favor in recent years.

CSP is present in 100% of fetuses, but over 85% of them fuse by 3–6 months of age . It has been loosely associated with schizophrenia, post-traumatic stress disorder, and chronic brain trauma .



References in movies

 * In Rocky V, Rocky Balboa is notified he has Cavum septum pellucidum.