Prepontine cistern

Anatomical space in the brain

The prepontine cistern is a cerebrospinal fluid-filled space located in the brain, specifically situated anterior to the pons and posterior to the clivus. It is part of the subarachnoid space, which is the area between the arachnoid mater and the pia mater, two of the three membranes that cover the central nervous system.

Anatomy

Diagram showing the prepontine cistern (labeled as "Interpeduncular cistern" in the image) and surrounding structures.

The prepontine cistern is bordered anteriorly by the clivus, a bony part of the skull base, and posteriorly by the pons, a major structure of the brainstem. Laterally, it is bounded by the petrous part of the temporal bone. Superiorly, it is continuous with the interpeduncular cistern, and inferiorly, it communicates with the pontomedullary cistern.

Within the prepontine cistern, several important neurovascular structures are located. These include the basilar artery, which is a major blood vessel supplying the brain, and the abducens nerve (cranial nerve VI), which is responsible for lateral eye movement. The prepontine cistern also contains the trigeminal nerve (cranial nerve V) as it exits the brainstem.

Function

The primary function of the prepontine cistern, like other cisterns in the brain, is to act as a reservoir for cerebrospinal fluid (CSF). This fluid serves several critical roles, including cushioning the brain, maintaining intracranial pressure, and removing metabolic waste. The prepontine cistern allows for the free flow of CSF between different parts of the subarachnoid space, facilitating the circulation of this vital fluid.

Clinical significance

Illustration of the brainstem, showing the location of the prepontine cistern in relation to the pons.

The prepontine cistern is of clinical importance due to its proximity to critical neurovascular structures. Pathological conditions affecting this area can lead to significant neurological deficits. For instance, aneurysms of the basilar artery can compress adjacent cranial nerves, leading to symptoms such as diplopia (double vision) or facial pain.

Additionally, tumors or cysts in the prepontine cistern can cause compression of the brainstem or cranial nerves, resulting in a variety of neurological symptoms. Imaging studies, such as MRI or CT scans, are often used to evaluate the prepontine cistern when such conditions are suspected.

Related pages

• Cistern (neuroanatomy)
• Basilar artery
• Pons
• Cerebrospinal fluid
• Subarachnoid space