Axial perspective of the supratentorial ventricular system and surrounding anatomy. The left side of the image demonstrates the lentiform nuclei (putamen and globus pallidus) separated from the thalamus by the posterior limb of the internal capsule. The lateral ventricles are bordered medially by the fornices, ribbon-like, C-shaped curvilinear fiber bundles that parallel the lateral ventricles in close proximity to the choroid plexus. Anteriorly, the frontal horns of the lateral ventricles are separated by a thin glial membrane termed the septum pellucidum. The head of the caudate nucleus forms a prominent and characteristic bulge in the ventrolateral wall of the frontal horn (Image courtesy of AL Rhoton, Jr.)