The anterolateral transpetrosal approach to the clivus and the pons. Preoperative embolisation of the inferior petrosal sinus.

Resection of skull base tumors is a real challenge in the field of neurosurgery. Anterior petrosectomy gives one of the best approaches to reach the clivus and the pons while avoiding cerebral retractions which are responsable for postoperative complications. Using a subtemporal extradural or an infratemporal preauricular route, the anterolateral transpetrosal approaches produce a resection of the anterior pyramidal bone around the petrous carotid artery. These approaches offer a direct view of the posterior fossa dura between the two petrosal sinuses, to give access to the petroclival area. However, exposure of the intradural structures in the foramen magnum area is always restricted because of the inferior petrosal sinus. Its peroperative hemostasis is always truly challenging on account of its size and encasement within a wide petrooccipital suture. The goal of the preoperative embolisation of the inferior petrosal sinus, whenever possible, is to allow its peroperative section without haemorrhage for a wider exposure along the lower clivus.