Abstract
Surgery for petroclival region tumors is one of the most difficult surgeries because the tumors are located in the deep midline area and furthermore, they are often situated in both the supra- and the infratentorial areas. We have used the posterior transpetrosal approach (PTA) or the lateral suboccipital approach (LSA), depending on the location of the main mass in each case. However, we now use the LSA more frequently after experiencing a certain amount of cases. This is because when using this approach the anatomy of the intraoperative view can be easily understood and it requires less time to expose the tumor. The LSA for petroclival tumor surgery means the infratentorial lateral supracerebellar approach, and the transtentorial approach can be added from the inferior side, if necessary. The main obstacles for the approach include the superior petrosal veins. Surgeons should know well the anatomy of the veins. In the case of the PTA, the superior petrosal veins are not a big problem but the vein of Labbe, temporal bridging veins, bridging veins to the tentorial edge and tentorial sinuses are obstacles. Herein, we describe the basic procedures and techniques of the LSA and the PTA and then, we explain the surgical anatomy of the deep venous system near the tentorial edge and the methods for dealing with the veins, especially the superior petrosal vein.
