Suboccipital Infratentorial Perspective of the Pineal Region. The cerebrovascular contents of the pineal region and ambient cistern are demonstrated. The superior colliculus, inferior colliculus and pineal gland are visible at center of image.  Coursing through the ambient cistern are the basal vein of Rosenthal, superior cerebellar artery, trochlear nerve, and posterior cerebral artery.  The tentorium prevents visualization of the full course of the posterior cerebral artery along the occipital lobe.  The internal cerebral vein, seen at top of image, courses superiorly (out of view of this image) within the roof of the third ventricle. The cerebral vein of Galen is also obscured from view by the tentorial dura. (Image courtesy of AL Rhoton, Jr.)