Suboccipital Transtentorial Perspective of the Pineal Region. The cerebrovascular contents of the pineal region are demonstrated. The basal vein of Rosenthal, superior cerebellar artery, trochlear nerve, and posterior cerebral artery all course within the ambient cistern. The internal cerebral vein courses superiorly out of view within the roof of the third ventricle (not shown). The cerebral vein of Galen is obscured from view by the tentorial dura. (Image courtesy of AL Rhoton, Jr.)