A, Posterosuperior view of the ventricles with the upper part of the cerebral hemisphere removed. The right occipital lobe and the adjacent tentorium have been removed to expose the upper surface of the cerebellum. Anterior caudate and anterior septal veins drain the walls of the frontal horn and empty into the anterior end of the internal cerebral vein. The posterior caudate veins drain the lateral wall of the body of the ventricle. B, Enlarged view. The internal cerebral and basal veins converge on the vein of Galen. The lateral atrial vein crosses the pulvinar and empties into the internal cerebral vein. The anterior calcarine vein drains the depths of the calcarine sulcus and joins the vein of Galen near its junction with the basal vein. The calcarine sulcus forms a prominence, the calcar avis, in the medial wall of the atrium. The posterior end of the hippocampus is located at the anterior edge of the calcar avis. The veins exiting the ventricle pass through the margins of the choroidal fissure located between the fornix and thalamus. C, The section of the left cerebrum has been extended forward into the temporal horn and hippocampus. The inferior ventricular vein drains the roof of the temporal horn and passes through the choroidal fissure to empty into the basal vein. The lateral atrial vein crosses the posterior surface of the pulvinar to empty into the internal cerebral vein. Only the stump of the basal vein remains. D, Enlarged view of the inferior ventricular vein passing through the choroidal fissure located between the fimbria and lower surface of the pulvinar, to join the basal vein. The deep end of the collateral sulcus, located on the lateral margin of the parahippocampal gyrus, forms a prominence, the collateral eminence, in the floor of the temporal horn lateral to the hippocampus. (Images courtesy of AL Rhoton, Jr.)