*4.3.2 Endoscopic-assisted posterior view of the petrous rhomboid to the condyle, medial aspect of the jugular foramen*

The IPS leads to finding the location of the medial aspect of the jugular bulb and jugular foramen. To visualize below the IAC, the endoscopic assisted visualization is necessary (**Figure 6**). The posterior view of the petrous rhomboid can provide exposure to the medial jugular complex up to the level of the hypoglossal canal (HGC). The location of the HGC indicates the same level of the condyle. The bone around the condyle is cancellous and can be easily drilled. When the posterior fossa dura is opened, the glossopharyngeal, vagal, and accessory nerves are seen. In the case of tumors originating from the bone, such as chordoma and chondrosarcoma, the tumor provides the surgical corridor by itself. The medial aspect of the jugular bulb is the deepest lesion because of the sigmoid sinus and jugular vein. This route is one of the choices of how to reach the medial jugular lesion.
