Step-by-step approach to the suprasellar region. The sellar bone has been removed to expose the sellar dura. The tuberculum sella has also been removed, exposing the underlying superior intercavernous sinus. The dura of the prechiasmatic sulcus has been exposed up to its anterior limit, which is formed by the dural fold corresponding to the limbus of the sphenoid. Note that bone removal has not yet extended to the level of the paraclinoidal internal carotid artery (ICA) and optic canal. (Image courtesy of JC Fernandez-Miranda)