Inferior Perspective of Dissected Temporal Lobe. Extensive temporal lobe dissection has permitted visualization of the optic radiations from their origin at the lateral geniculate nucleus (LGN) to near their termination in the primary visual cortex.  Meyer's loop projects anteriorly from LGN into the temporal lobe parenchyma inferolateral to the atrium of the lateral ventricle.  The atrium is an important landmark to consider when performing intraventricular surgery given the close proximity of the optic radiations. The optic tract is seen coursing from its origin at the optic chiasm, along the lateral edge of the infundibulum of the hypothalamus, then along the lateral edge of the crus cerebri, to terminate in the lateral geniculate nucleus. (Image courtesy of AL Rhoton, Jr.)