Skull Base Surgery of the Posterior Fossa

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tumor origin determined the direction of the
seventh to eighth nerve displacement [ 18 ]. They
used transpetrosal or translabyrinthine
approaches to reach the tumors anterior to the
7–8 nerve complex, but we have been able to
resect these using the retrosigmoid approach
complemented by intradural drilling of the petro-
sal bone, which facilitates hearing preservation.
Over recent years, the surgical approach of
choice has shifted from a transpetrosal or trans-
labyrinthine approach to the retrosigmoid

approach. This has been driven by improved out-

comes and hearing preservation with the retrosig-

moid approach. When Thomas and King reported

a series of CPA tumors and separated out the

petrous face meningiomas from the petroclival

tumors, they also observed the clinical syndromes

described above [ 17 ]. They used a retrosigmoid

approach for the posterior petrous tumors but

required the more invasive translabyrinthine or

transcochlear approach to the midpetrosal tumors.

They used a middle fossa transtentorial approach

Fig. 8.5 Small PPFM. Preoperative axial T1 post-contrast MRI showing the tumor in the region of the vestibular
aperture

S.T. Magill et al.