Step-by-step approach to the suprasellar region. The dural opening has been extended to the planum sphenoidale to expose the medial fronto-orbital gyrus, gyrus rectus, olfactory tract, and interhemispheric fissure. The optic chiasm is now fully identified. The dura of the medial wall of the optic canal has been carefully removed to provide access to the intracanalicular portion of the optic nerve. (Image courtesy of JC Fernandez-Miranda)