Navigating the Skull Base



   The petro-occipital fissure can be used to locate structures at the skull base in the following manner. A line is drawn through the petro-occipital fissure that can be extended anteriorly through the foramen lacerum, the pterygoid canal, and the pterygopalatine fossa. The line is extended posteriorly to the jugular foramen and then directed medially through the hypoglossal canal. This is illustrated to the left for left-sided structures.