Skull Base Surgery of the Posterior Fossa

43

attempt to preserve the labyrinthine artery; however
partial vestibulopathy from a retained inferior
vestibular nerve can result in persistent unsteadi-
ness in some patients. For this reason, we recom-
mend cutting the inferior vestibular nerve medial
to the Scarpa’s ganglion, but not dissecting it at
the fundus of the IAC (Fig. 3.6).
Once the tumor is removed, the tumor bed is
irrigated and hemostasis is obtained. Papaverine-
soaked Gelfoam is placed along the cochlear
nerve to prevent vasospasm. Abdominal fat is
used to close the defect in the IAC. The retractor

is removed, and the temporal lobe is allowed to

re-expand. The craniotomy flap is replaced with

titanium mini-plates, the wound is closed with

absorbable sutures in layers, and a mastoid-type

pressure dressing is placed.

Surgical Technique: Translabyrinthine

Approach

For the translabyrinthine approach, the operating

room setup is identical to that for a standard mas-

toidectomy. The ipsilateral scalp is shaved four

fingerbreadths above and behind the postauricular

Fig. 3.4 The internal
auditory canal is
exposed and the facial
nerve is identified
adjacent to Bill’s bar.
The dura of the internal
auditory canal is opened
on its posterior surface
with a micro knife

Fig. 3.5 The arachnoid

surrounding the facial

nerve is divided with a

right-angle hook. The

facial nerve is separated

from the tumor from

medial to lateral. It is

important to identify the

vestibular-facial nerve

anastomoses and divide

them sharply, to avoid

traction injury to the

facial nerve

3 Middle Fossa and Translabyrinthine Approaches