The venous blood is drained from the brain by small cerebral veins, which are devoid of muscular coat and valves. Venous drainage of Cranium do not accompany the cerebral arteries.
this drainage system lie in the piamater and subarachnoid space. the ascending cerebral veins drain the convex and medial faces of the hemisphere and open into the dorsal longitudinal (some into the transverse) sinus of the dura mater. The descending cerebral veins drain the ventral part of the convex face of the hemisphere and open in to the vena rhinalis posterior.
The basal cerebral veins from the trunk, the rhinalis posterior joins the dorsal petrosal sinus.
The deep cerebral veins draining the basal ganglia and choroid plexuses join to form the great cerebral vein, which passes upwards and backward behind the splenium of corpus callosum and is continued, as the straight sinus, which joins the dorsal longitudinal sinus.
The dorsal cerebellar veins drain into the occipital and dorsal petrosal sinuses.
The ventral cerebellar veins go to form the basilar plexus.
The veins from pons and medulla join the basilar plexus and the occipital and dorsal petrosal sinus.
