The Classical Pathways of Occipital Lobe Epileptic Propagation Revised in the Light of White Matter Dissection

Figure 3

(a) Basal view of the right hemisphere showing the ventral portion of the ILF (vILF) with its double originating branches from the fusiform gyrus (Fu) and superficial lingual gyrus (Li). The bundle connects these two posterior basal regions to the parahippocampal gyrus (PHG). (b) Basal view of a right hemisphere after the removal of the dILF and vILF. The lingual-amygdala bundle (Li-Am/green) is completely exposed and its relationship with the ventricle and the sagittal stratum of Sachs (SSS) cranially is demonstrated. The Li-Am connects the lingual gyrus (Li) in an arch shaped bundle, which follows the wall of the lateral ventricle and at the level of the tip of the temporal horn turns medial to terminate in the inferolateral portion of the amygdala (Am). (c) Inferolateral view of a right hemisphere with the optic radiation (OR) completely exposed. The temporal loop of Meyer (MeL) is prominent anteriorly with respect to the other fibres. The optic radiation fibres run within the internal layer of the sagittal stratum of Sachs (SSS), inferior and lateral to the lateral ventricle, and turn medially to end at the level of the primary visual cortex (V1). The arcuate fasciculus (AF) and the internal capsule (IC) can be considered as superficial and deep landmarks, respectively. AF: arcuate fasciculus; BS: brain stem; HB: hippocampus body; HH: hippocampus head; OP: occipital pole; Ta: tapetal fibres; TP: temporal pole; Un: uncus.

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