Cavum veli interpositi

Anatomical space in the brain

The cavum veli interpositi is a potential space within the brain that is located between the layers of the pia mater and the arachnoid mater. It is situated in the midline of the brain, above the third ventricle and below the corpus callosum. This space is part of the subarachnoid space and is filled with cerebrospinal fluid (CSF).

Anatomy

The cavum veli interpositi is formed by the separation of the layers of the velum interpositum, a thin membrane that is part of the meninges. The velum interpositum is located between the fornix and the thalamus, and it contains the internal cerebral veins and the choroid plexus of the third ventricle.

Cavum veli interpositi in a brain MRI

The cavum veli interpositi is bordered superiorly by the fornix, inferiorly by the thalamus, and laterally by the choroid plexus. It communicates with the third ventricle and the quadrigeminal cistern, allowing the flow of cerebrospinal fluid.

Development

The cavum veli interpositi is present during fetal development and is usually obliterated by the time of birth. However, in some individuals, it may persist into adulthood. When it persists, it is typically asymptomatic and is often discovered incidentally during neuroimaging studies.

Clinical Significance

While the cavum veli interpositi is generally of no clinical significance, its presence can sometimes be mistaken for a cyst or other pathological condition on imaging studies. It is important for clinicians to recognize this anatomical variant to avoid unnecessary interventions.

In rare cases, an enlarged cavum veli interpositi may be associated with other congenital anomalies or may contribute to hydrocephalus if it obstructs the normal flow of cerebrospinal fluid.

Related pages

• Cavum septi pellucidi
• Cavum vergae
• Third ventricle
• Cerebrospinal fluid
• Meninges