A cistern is an expansion of the subarachnoid space that enables additional areas of storage and cushioning of the cerebrospinal fluid.
Cistern means “box” in Latin and structurall us characterized by an expansion of the subarachnoid space created by the separation of the archnoid and pia mater. The arachnoid membrane lines the inner surface of the dura mater. By contrast, the pia mater adheres to the central nervous system. When the two separate the accumulation of cerebrospinal fluid between them creates a cistern.
The major cistern include;
ambient cistern also known as the cistern of the great cerebral vein
quadrigeminal plate cistern