85increased CSF pressure as suggested by imaging
findings (e.g., dilated ventricles, empty sella,
dilated optic nerves). Finally, the route for tumor
resection should be adequate to reconstruct the
skull base, thus avoiding the morbidity of a sec-
ond approach.
The authors favor reconstruction of skull base
defects using pedicled vascular flaps, multilayer
reconstruction techniques, and the aforemen-
tioned principles, especially for central skull base
defects. However, multiple options are available
to reconstruct the skull base bone and dura and
can be divided in free grafts, synthetic/heterolo-
gous materials, and vascularized flaps.
Free autografts imply the harvesting of tissue
from a donor site that is then transferred and
implanted in a recipient site. They lack their own
vascularization as there is no attachment to the
donor site; therefore, they require a well-
vascularized recipient bed to optimize the take of
the graft. Commonly used free autografts include
the following: free mucoperiosteal/ mucoperi-
chondrial autograft, autologous fascia lata graft,
free fat autograft, free cartilage autograft, and
free bone autograft. The synthetic and heterolo-
gous materials most commonly used are collagen
matrix and acellular dermal matrix processed
from banked human cadaver skin [ 45 ].
There are numerous vascularized flaps that
can be used to reconstruct the ventral skull base,
and they are divided into intranasal or local and
extranasal or regional. The main intranasal flaps
that are suitable for reconstruction of petroclival
defects include the nasoseptal flap, the posteri-
orly based lateral nasal wall flap, and the inferior
turbinate flap. The main extranasal flaps are the
temporoparietal fascia flap and the pericranial
flap. Lumbar drain is not used routinely, but may
be considered in large posterior fossa dural
defects [ 45 ].
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