Left lateral view of cerebrum. The principal blood supply to the cerebrum is via branches of the anterior and middle cerebral arteries. In this perspective, branches of the middle cerebral artery emerge from the Sylvian or lateral fissure and radiate onto the surface of the lobes of the cerebrum. Venous return here is via a superficial cortical venous system that involves anastomotic connections between the superficial middle cerebral vein, the vein of Trolard (superior anastomotic vein), and vein of Labbe (inferior anastomotic vein). The superficial middle cerebral vein is located in the lateral fissure. It is connected to the superior sagittal sinus, located in the superior margin of the falx cerebri, by the vein of Trolard, which usually courses in the post-central sulcus. It is also connected to the transverse sinus by the vein of Labbe. There is much variability in these interconnections, from a balanced  network, to independent drainage, to dominance of one channel at the expanse of the others. Frontal and parietal veins, draining respective lobes, empty into the superior sagittal sinus. Seen also here are lacunae laterales, lateral expansions of the sinus into which project arachnoid villi. The transverse sinus continues laterally as the sigmoid sinus, which ends in the jugular bulb at the jugular foramen. The petrous bone has been drilled to expose the bony labyrinth and the semicircular canals. The tympanic portion of the facial nerve can be seen inferior to the lateral semicircular canal. (Image courtesy of M Nunez)