Venous Drainage of the Medial Temporal Region. E, Inferior view of another basal vein. The striate segment of the basal vein is formed by the union of the deep MCV, anterior cerebral, inferior striate, and olfactory veins on the lower surface of the anterior perforated substance and ends at the junction with the peduncular vein. The anterior peduncular segment begins at the junction with the peduncular vein. The posterior peduncular segment begins where the inferior ventricular vein joins the basal vein. The inferior ventricular vein drains the roof and lateral wall of the temporal horn. Thalamic veins drain into the proximal part of the posterior half of the basal vein. The posterior longitudinal hippocampal vein runs in the posterior part of the hippocampal sulcus, and receives the transverse hippocampal veins that drain the posterior body and tail of the hippocampus. In this specimen, the posterior longitudinal hippocampal vein drains into the internal cerebral vein. The calcarine vein drains the anterior part of the lingual gyrus and cuneus, runs anteromedially in the anterior calcarine sulcus, and enters the quadrigeminal cistern to drain into the vein of Galen-basal vein junction. F, Basal view of the striate and anterior peduncular segments of the basal vein. The orientation is the same as in part E. The part of the amygdala below the level of the optic tract has been removed. The carotid and crural cisterns have been opened to expose the striate and anterior peduncular segments of the basal vein. The anterior and deep medial cerebral veins meet to form the striate segment of the basal vein. In this specimen, the anterior cerebral vein is larger than the deep MCV. The inferior striate veins have no appreciable cisternal segment between the point of emergence from the anterior perforated substance and the point of entry into the anterior and deep medial cerebral veins. The anterior segment of the uncus is drained by an uncal cortical vein and, in this case, the anterior uncal vein empties into the striate segment. The anterior peduncular segment, also called the anterior basal anastomotic vein, begins where the peduncular vein joins the basal vein, and communicates the striate segment with the posterior peduncular segment, which starts at the junction with the inferior ventricular vein. In this specimen, the amygdalar vein, which courses on the ventricular surface of the amygdaloid nucleus, drains into the anterior basal anastomotic vein. The anterior peduncular segment (anterior basal anastomotic vein) is positioned between the peduncular and inferior ventricular veins. The posterior peduncular segment extends from its junction with the inferior ventricular vein to the mesencephalic segment (posterior basal anastomotic vein). G, Inferior view of the roof of another right temporal horn. The junctional point between the inferior ventricular vein and the peduncular segment marks the transition between the anterior and middle segments of the MTR, and corresponds to the cisternal level of the inferior choroidal point and the junction of the crural and ambient cisterns. Several large subependymal veins draining the roof and lateral wall of the temporal horn join to form the inferior ventricular vein. In this case, the amygdalar vein drains separately from the inferior ventricular vein into the anterior basal anastomotic vein. (Images courtesy of AL Rhoton, Jr.)