Pontine cistern

The pontine cistern (or prepontine cistern ) is a subarachnoid cistern situated ventrally/anteriorly to the pons.   It contains the basilar artery.  Each lateral aperture opens into the pontine cistern just posterior to the cranial nerve VIII.  

Anatomy
The pontine cistern is situated ventrally/anteriorly to the pons, in the interval between ventral aspect of the pons, and the clivus. 

Contents
The cistern contains the origin of the abducens nerve (CN VI), the basilar artery and the origin of the basilar artery and of its branches, and the anterior inferior cerebellar artery, and superior cerebellar artery.

Relations
It is continuous inferiorly with the subarachnoid space of the spinal canal, posterolaterally with the cerebellopontine cistern of either side, and rostrally/anteriorly with the interpeduncular cistern.