Frontal Section at the Level of the Optic Chasm

 Frontal Section at the Level of the Optic Chasm

A section through the anterior wall of the third ventricle shows parts of the dien-cephalon and telencephalon. Ventrally lies the fiber plate of the decussation of the optic nerve, the optic chasm (D8). A rostral excavation of the third ventricle, the preop-tic recess (D9), is seen above it. The globuspallidus (CD5) appears laterally to the inter-nal capsule. All other structures belong to the telencephalon: the two lateral ven-tricles (D10) and the septum pellucidum (D11) enclosing the cave of the septum pel-lucidum (D12), the caudate nucleus (D13),the putamen (CD14), and at the base, the ol-factory area (D15) (anterior perforated sub-stance). The corpus callosum (D16) and the anterior commissure (D17) connect the twohemispheres. Other fiber systems shown in the section are the fornix (D18) and the lateral olfactory stria (D19).


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