Extradural approach to the upper clivus. The bone covering the sellar, parasellar, clival and paraclival regions has been removed. The sellar dura is being elevated to expose the dorsum sella and the base of the posterior clinoids. This extradural approach to the upper clivus, while sufficient in selected cases, provides limited access and poor visualization of the posterior clinoids. (Image courtesy of JC Fernandez-Miranda)