E, The lower layer of tela has been opened to expose the massa intermedia, posterior commissure, and the floor of the third ventricle. The ependyma covering the anterior septal vein has been opened so that a short segment of the vein can be mobilized. The possibility of damaging the thalamostriate vein is reduced by allowing the choroid plexus to remain attached to the thalamus and the upper surface of the vein. F, The interforniceal approach is completed by incising the fornix longitudinally in the midline. Each half of the body of the fornix has been retracted laterally to expose the internal cerebral veins, medial posterior choroidal arteries, and the layer of tela choroidea that attaches to the striae medullaris thalami. G, The tela has been opened to expose the floor of the third ventricle and the massa intermedia. H, The view has been directed posteriorly toward the aqueduct and the posterior and habenular commissures. The pineal recess extends into the base of the pineal between the habenular and posterior commissures. The pineal gland extends backward from the pineal recess. (Images courtesy of AL Rhoton, Jr.)