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124 Section II: Intracranial Procedures

Figure 13.6 Incision through the skin and temporalis fascia and muscle.
The biopsy tract is being removed with the mass. In this case, the mass had
invaded the temporalis fascia so it could not be preserved.

A Figure 13.8 A pneumatic drill is used to make a circumferential incision in
the skull. Continuous irrigation during drilling will help dissipate the heat
from the bone and surrounding tissues.

Since local recurrence is a significant concern with both malig-
nant and benign tumors, a 1–2 cm safety margin of bone beyond
the mass is planned to reduce local recurrence [2,3,19]. This mar-
gin should be identified and marked based on planning from
advanced imaging. It is important that imaging is consulted for
this approach as the mass may have a more substantial internal
component than what is externally visible. If skull excision is
based on the visible mass, there is an increased risk of disruption
of the mass during drilling with subsequent incomplete margins.
A pneumatic drill and burr is then used to make a circumferen-
B tial incision into the skull. Alternatively, the CUSA NXT 35 kHz
Neuro Tip (Integra LifeSciences Corporation, Plainsboro, NJ) can
been used to cut through the skull, thereby avoiding the bone dust
that could seed the area with tumor cells (Figure 13.7). Bone thick-
ness should be determined on the preoperative CT and can vary
significantly. Saline irrigation over the burr and bone is used to
minimize heat conduction and necrosis (Figure 13.8). When using
a drill and burr, the incision is continued until the inner periosteum
can be palpated as soft circumferentially and a curette or rongeur
can be used to complete the incision. Following circumferential
incision, the bone segment should be moveable and should be
removed carefully as it can be closely associated with or adherent to
the dura or sinuses. A damp cotton‐tipped applicator, curette, or
Freer periosteal elevator can be useful to gently separate the bone
segment from the dura (Video 13.2). Any minor bleeding encoun-
tered can be addressed with a hemostatic sponge, bipolar electroco-
Figure 13.7 (A) Resection of the skull mass with the bone‐cutting CUSA agulation with lavage or gentle pressure. The resected segment
NXT 35 kHz Neuro Tip (black arrow). White arrow points to cut through should then be evaluated to ensure that an adequate margin has
the mid‐sagittal crest of the skull. (B) White arrows outline the cutting line been achieved in all directions and further bone removed as
caudal to the mass. Using this method, no bone dust is produced. necessary with rongeurs. Gentle irrigation of the site is performed