Posterior Fossa Cisterns
Last Updated: March 25, 2020
The subarachnoid space, situated between the pia mater and the outer arachnoid membrane, expands at the base of the brain, around the brainstem, and in the tentorial incisura to form compartments filled with cerebrospinal fluid. Numerous trabeculae, septa, and membranes cross the space between the pia mater and the outer arachnoid membrane to divide the subarachnoid space into smaller compartments called cisterns. All of the cranial nerves and majo...