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Infratemporal Approach
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gums. Early visual or image-guided identification of
the nerve should prevent this injury.
– Injury of V3, either planned or accidental, will lead to
both sensory (lower third of face, lower teeth, chin,
lip, auricle, and external auditory canal) and motor
(mastication weakness) deficits. Again, if preservation is preferred, early identification with image
guidance is recommended.
– Addition of a Caldwell-Luc approach adds the poten-
tial for injury to the infraorbital nerve at its foramina
inferior to the orbital rim. Dental paresthesias have
also been reported.
• Cosmetic
– Addition of the Denker’s approach often leads to
posterior retraction of the lateral nasal ala. Inadvertent injury to the nasolacrimal canal may lead
to epiphora.
25.6 Tips and Tricks
• A large maxillary antrostomy with removal of the mid-
dle and inferior turbinate (endoscopic medial maxillectomy) is critical for wide-field exposure of the PtPF and
access to the ITF.
• If access is difficult, a Denker’s or Caldwell-Luc ap-
pr
oach may be added for increased lateral exposure
and utilization of multiple instruments.
• The IMAX takes a random course through the ITF and
must be carefully followed laterally into the ITF. Isolating and controlling the artery lateral to the pathologic
process is critical for safe resection of tumor.
• The floor of the maxilla limits inferior access of the ITF.
Careful preoperative evaluation of CT and/or MR images is important to predict ability of access.
• The middle meningeal and carotid arteries are
immediately posterior and lateral to foramen ovale.
Understanding of this anatomy and the judicial use of
image guidance will help prevent vascular injury.
References
1. Brors D, Draf W. The treatment of inverted papilloma. Curr Opin
Otolaryngol Head Neck Surg 1999;7:33–38
2. Theodosopoulos PV, Guthikonda B, Brescia A, Keller JT, Zimmer LA.
Endoscopic approach to the infratemporal fossa: anatomic study.
Neurosurgery 2010;66(1):196–202, discussion 202–203
3. Zimmer LA, Hart C, Theodosopoulos PV. Endoscopic anatomy of
the petrous segment of the internal carotid artery. Am J Rhinol
Allergy 2009;23(2):192–196
265
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Chapter 26
6
traindications to Surgery
nd Complica
275
Conclusi
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26.1 Indications for an Expanded
Endonasal Approach 268
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26.2 Contraindications to an
Expanded Endonasal
Approach 268
26.3 Surgical Steps 268
26.4 Reconstruction 273
26.5 Discussion 274
26.6 Contraindications to Surgery
and Complications 275
26.7 Conclusion 276
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26 Nasopharyngectomy
Raewyn G. Campbell, Daniel M. Prevedello, Ricardo L. Carrau
Introduction
The most common malignant tumor of the nasopharynx
is nasopharyngeal carcinoma (NPC). Other epithelial
tumors involving the nasopharynx include melanoma
and those with glandular differentiation (e.g., adenoid
cystic carcinoma, adenocarcinoma, mucoepidermoid
carcinoma), as well as malignancies of mesenchymal
origin (e.g., rhabdomyosarcoma, melanoma, reticular cell
sarcoma and follicular dendritic cell sarcoma) or lymphoreticular origin (e.g., lymphoma, plasmacytoma).
Traditionally, the mainstay of treatment for primary
NPC is radiotherapy or concurrent chemoradiotherapy.
Overall, the recurrence rate after primary treatment of
NPC is around 10%.
rence rate for NPC is 19 to 56%, varying according to the
stage at presentation.
gional recurrence or persistence include re-irradiation
or surgery.
4 to 57%, again, depending on the stage.
tumors that persist or recur after radiation have demonstrated their resistance to this treatment modality and
are, therefore, less likely to respond to further radiotherapy, although the radiation modality is likely to influence outcomes (intensity modulated radiation therapy
vs. proton radiotherapy vs. stereotactic vs. brachytherapy). Regardless, surgical salvage for NPC has been shown
to
morbidity than re-irradiation.
salvage surgery for patients with nasopharyngeal tumors
have yielded a local control rate of 65% at 33 months.
thermore, 5-year overall and disease-free survival rates
of 75.1 and 58.1%, respectively, have also been reported
for endoscopic approaches to nasopharyngeal tumors.
Surgery is, however, the primary treatment modality for
malignancies with glandular or mesenchymal differentiation, such as adenoid cystic carcinoma, adenocarcinoma,
and sarcomas, as these tumors are traditionally resistant
to radiation, thus implying that the completeness of surgical resection is critical for any possibility of cure.
7
offer superior local control
4
More specifically, the 5-year recur-
5,6
Management options for locore-
Survival rates after re-irradiation vary from
2,4,11–14
and results in less
11,14–16
Reports addressing
1,2
8–10
It is felt that
2
Fur-
2,18,19
3
17
26.1 Indications for an Expanded
Endonasal Approach
• Locoregional recurrence or persistent NPC after chemo-
radiation treatment.
• Primary surgery for adenoid cystic carcinoma, adeno-
carcinoma, or traditionally radioresistant malignancies
(salivary or mesenchymal origin).
• Tumors that extend below the level of the soft palate
(Fig. 26.1d).
• Extensive orbital invasion.
26.3 Surgical Steps
26.3.1 Preoperative Assessment
All patients should undergo a thorough preoperative
assessment and, whenever possible, should be presented
at a multidisciplinary tumor board. Work-up should
include a confirmatory biopsy and imaging (contrastenhanced computed tomography angiography [CTA] scan,
magnetic resonance imaging [MRI] scan, and positron
emission tomography scan fused to a CT scan [PET/
CT scan]). Imaging should be performed according to
appropriate surgical navigation protocols. Consideration
for a carotid artery balloon occlusion test should be given
to any patient who has tumor abutting or involving the
ICA, and possible sacrifice or stenting of the ICA should
be discussed with the patient. Preoperative circulating
cell-free Epstein–Barr virus (EBV) DNA may predict the
chance of resection with negative margins in patients
with NPC and, therefore, may help to identify patients
who will benefit from adjuvant treatment.
DNA can also provide early detection of local and distant
recurrences postoperatively.
21
26.3.2 Preparation and Set-up
We recommend intraoperative electrophysiologic
monitoring for any patient with a tumor that is in
the proximity of, or in contact with, cranial nerves or
major neurovascular structures. Somatosensory evoked
potentials monitor early signs of cerebral compromise
due to ischemia, edema, hemorrhage, or contusion.
Electromyography is recommended for any resection that
may involve the posterior orbit, superior orbital fissure,
cavernous sinus (CN III–VI), hypoglossal canal (CN XII),
jugular foramen, or parapharyngeal space (CN IX–XI).
We prefer a two-surgeon, four-handed technique and
the use of image guidance/navigation system throughout
the procedure (e.g., Stryker Navigation). A 0-degree rodlens endoscope is used predominantly; however, we
also use the 30-, 45-, and, occasionally, 70-degree rodlens endoscopes also. To clean the lens of the endoscope
throughout the procedure, lens irrigation systems are
available; however, we prefer manual irrigation with
warm saline.
20
Plasma EBV
26.2 Contraindications to an
Expanded Endonasal Approach
• Tumors that extend posterior to, or surround, the inter-
nal carotid artery (ICA; Fig. 26.1a, b).
• Extensive involvement of the skull base and dura
(Fig. 26.1c).
268
26.3.3 Approach and Resection
The extent and location of the tumor, its relationship to
critical structures, and available tissues and techniques
for reconstruction dictate the exposure. Other factors to
consider are the patient’s age, comorbidities, and the skills
and experience of the surgical team. Margin status is an
important prognostic factor for local control and overall
survival after surgical salvage for recurrent NPC.
22–24
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Fig. 26.1 (a, b) Axial T1 MRI scans
with contrast of a nasopharyngeal
carcinoma not suitable for an
endoscopic resection due to the
tumor’s eff acement of the left internal
carotid artery (arrow). (c) Coronal
T1 MRI scan with contrast of the
same patient demonstrating dural
enhancement (white arrow) along the
middle cranial fossa dura. (d) Sagittal
MRI scan demonstrating tumor
extension (white arrows) below the
level of the soft palate (asterisk).
a
c d
b
The ability to achieve negative margins is dependent on
many factors: adequate exposure, tumor involvement of
critical structures, and T-stage.
Approaching the tumor via the natural air spaces of
the nasal cavity (i.e., transnasal corridor) is suitable for
a small lesion localized to the central nasopharynx. This
may include lateralization of the inferior turbinates.
A more extensive exposure will provide access to the
posterior and superior nasopharynx including the floor
of the sphenoid sinus. This approach involves resection
of the posterior inferior turbinates and a limited
posteroinferior septectomy to facilitate binarial access.
This approach can also be extended anterosuperiorly to
involve resection of the front face of the sphenoid sinus
and a complete sphenoidectomy. The approach can also
be extended inferiorly to remove the lower third of the
clivus and anterior arch of C1.
• The patient is positioned supine in the reverse Tren-
delenburg position with the head tilted to the left and
rotated to the right and neck slightly flexed.
• Perioperatively, all patients receive a fourth-generation
cephalosporin plus vancomycin, if they are methicillin-resistant Staphylococcus aureus positive.
• The nasal mucosa is prepared with topical 1:10,000
epinephrine-soaked pledgets which are left in place
during the positioning and draping of the patient.
• The pledgets are removed and the nasal mucosa is in-
jected with 1% lidocaine with 1:100,000 epinephrine,
including septum, axilla of the ipsilateral (to the tumor) middle turbinate, and the region of the sphenopalatine arteries (SPAs) bilaterally.
• If the torus tubarius is involved, then resection of the
medial cartilaginous eustachian tube (ET) is required.
*
For this resection, a mucoperiosteal incision on the
posterolateral nasal cavity wall is made vertically just
posterior to the inferior turbinate, over the ascending
process of the palatine bone and medial pterygoid plate.
This incision may be made more anteriorly as dictated
by the tumor extent. The dissection then continues
posteriorly in a submucoperiosteal plane exposing the
medial pterygoid plate. The torus is sharply transected
and soft tissue dissection continues until the tumor is
removed and histopathologic examinations (i.e., frozen
sections) are negative.
• We prefer a transpterygoid approach for any tumor
that extends lateral into the fossa of Rosenmüller. This
includes a medial maxillectomy and transposition of
the soft tissue contents of the medial pterygopalatine
fossa. This exposes the entire height of the pterygoid
process and permits excision of the medial pterygoid
plate and its base to the level of the foramen rotundum.
• The contralateral inferior turbinate is out-fractured us-
ing a Freer dissector.
• The ipsilateral middle turbinate is resected using
straight endoscopic scissors and straight through-biting Blakesley forceps. It is imperative to keep the skull
base in view when removing the middle turbinate to
avoid violating the skull base and creating a cerebrospinal fluid leak (Fig. 26.2). The mucosa from the turbinate is then harvested and stored in saline.
• The uncinate process is removed using back-biting
forceps, a ball-tipped seeker probe, and the microdebrider.
• The natural ostium of the maxillary sinus in then
identified and extended posteriorly using the straight
through-cutting forceps and microdebrider.
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• An ipsilateral complete anterior and posterior eth-
moidectomy is then undertaken using through-cutting
forceps (straight and 45 degree) and the microdebrider.
• The inferior third of the superior turbinate is resected
with straight through-biting/through-cutting Blakesley
forceps and the sphenoid ostium is identified bilaterally.
• As long as the roof of the nasopharynx, posterior sep-
tum, pterygopalatine fossa, sphenoid rostrum, and posterior choana are free of tumor, a nasoseptal flap
25
is
elevated. Another consideration is radiation necrosis,
which could also compromise the blood supply to the
flap. If there is any uncertainty, a Doppler probe may be
used intraoperatively to assess the viability of the pedicle. The flap is elevated on the contralateral side as the
internal maxillary artery is sacrificed on the ipsilateral
side during the approach.
• The nasoseptal flap may be stored in the maxillary si-
nus or may be placed along the lateral nasal wall, which
avoids significant congestion of the flap. To do this, a
suture is placed in the anterior aspect of the flap, which
is then attached to a hemostat. The hemostat hangs
from the nasal cavity and uses gravity to hold the flap
in place. The shaft of the endoscope will hold the flap
out of the way and prevent injury during the surgery. If
the flap is on the contralateral side, then instruments
must be inserted into the nasal cavity under direct vision to avoid injury.
• If a nasoseptal flap is not available, then a temporopa-
rietal fascia flap may be used for reconstruction. This
flap is introduced to the nasal cavity via a transpterygoid tunnel.
26
• After the posterior bony septectomy, a reverse septal
flap is then created to further protect the remnant septum and to minimize crusting postoperatively.
27
The inferior incision of the reverse flap is made approximately 5 mm above the remnant septum (Fig. 26.3). This
mucosa is then rotated to the contralateral side and
used as an inferiorly based flap covering the exposed
bone of the maxillary crest.
• This creates a complete posterior septectomy, thus pro-
viding a panoramic view of the nasopharynx, allowing
a more lateral access for instrumentation, and allowing
a two-surgeon, four-hand technique. Intraoperative
image guidance may be used to ensure the septectomy does not include the structural support of the nasal
septum (that portion inferior to the nasal bones and
resting over the premaxilla); thus avoiding a saddle
nose deformity.
• Silicone splints are cut to size and sutured to the sep-
tum to protect the reverse flap from inadvertent injury due to the passage of instruments throughout the
remainder of the procedure and to prevent synechiae.
This wound heals within 1 to 2 weeks.
27
• Bilateral wide sphenoidotomies are then created using
the Kerrison rongeurs and a drill. We prefer a highspeed drill and a 3 to 4 mm coarse or hybrid diamond
burr (e.g., Midas Rex Stylus Legend, Medtronic, or
Stryker Total Performance System). Removal of the
sphenoid floor will reduce the likelihood of posterior
choanal stenosis as many of these patients will have
failed radiotherapy and will be at increased risk.
• The sphenoid floor is then drilled down until it is flush
with the clivus.
• A medial maxillectomy is then undertaken extending
from the roof of the antrum/inferior orbital wall to the
nasal floor and from the nasolacrimal duct to the posterior wall of the antrum.
• Using back-biter forceps, straight through-cutting for-
ceps, and the microdebrider, the maxillary ostium is
opened maximally. Posteriorly, the dissection extends
to the level of the posterior wall of the maxillary sinus. Care must be taken when removing portions of
the perpendicular plate of the palatine bone during
this procedure as 38% of posterolateral nasal arteries
(branch of the SPA) run anterior to the posterior wall of
the maxillary sinus and brisk bleeding may be encoun-
28
tered.
Anteriorly, the dissection ends just posterior to
the nasolacrimal duct.
Fig. 26.2 Endoscopic view of scissors (white dashed arrow)
poised to remove the middle turbinate (asterisk: axilla of
middle turbinate) with the skull base in view (white arrow).
270
*
Fig. 26.3 Endoscopic view of the inferior incision of the
reverse fl ap made ~0.5 cm above the fl oor of the nose.
• The middle third of the ipsilateral inferior turbinate
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is removed. First, the inferior turbinate is medialized;
then, an incision is placed posterior to the level of the
nasolacrimal duct opening using angled scissors. The
remainder of the turbinectomy is completed using turbinectomy scissors or through-biting Blakesley forceps
and the microdebrider.
• The medial wall of the maxillary sinus is then removed to
the level of the floor of the nose using the microdebrider, through-cutting Blakesley forceps, and the drill. Prior
to this, a small flap of medially based mucosa is elevated
off the medial wall of the maxilla and floor of the nose to
be rotated over the exposed bone once the medial wall is
drilled flush with the floor of the nasal cavity (Fig. 26.4).
• The SPA may be identified immediately posterior to
the crista ethmoidalis, clipped, cauterized, divided, and
mobilized laterally.
• Following a medial maxillectomy, access to a tumor
that extends laterally (e.g., into the infratemporal fossa) may be limited by the anchored nasolacrimal duct.
If the tumor dictates that further lateral resection is
required, maneuvering instruments from the contralateral side via the posterior septectomy will increase
lateral access. If still further access is required laterally, then an endoscopic Denker’s approach (i.e., Sturman–Canfield approach) will permit instrumentation
to reach the infratemporal fossa. Removal of the anteromedial aspect of the maxilla/bone of the piriform
aperture also permits more lateral maneuverability for
instrumentation (Fig. 26.5).
• An endoscopic Denker’s approach begins with removal
of the remainder of the inferior turbinate. Next, a vertical incision is made over the anterior border of the piriform aperture, which is just anterior to the head of the
inferior turbinate (Fig. 26.6). This edge can be palpated
with a blunt instrument. The incision is extended down
through the periosteum to expose the anterior aspect of
the maxilla. The mucosa is then elevated in a subperiosteal plane using a Cottle elevator or Freer dissector.
Elevation continues laterally until the infraorbital nerve
is identified and elevated and thus preserved (Fig. 26.7).
Nasopharyngectomy
Fig. 26.4 Endoscopic view of a medially based fl ap made
prior to removing the medial wall of the maxillary sinus during
a medial maxillectomy.
• The anteromedial maxillary wall is removed using
the hi
gh-speed drill (Fig. 26.8). The bone surrounding
the nasolacrimal duct is drilled and the duct is divided sharply. A sharp transection obviates the need for
stenting. If it is possible to preserve the nasolacrimal
duct, then the dissection continues inferior to it using
back-biting rongeurs and the high-speed drill. However, a full Denker’s approach involves the removal of the
anteromedial aspect of the ascending process of the
maxilla and transection of the nasolacrimal duct.
• Removal of the piriform aperture and anterior maxillary
wall results in a single cavity comprising the maxillary,
ethmoid, and sphenoid sinuses and the nasal cavity and
a b
Fig. 26.5 Macroscopic view of a skull demonstrating the area of excision of the maxilla before (red dotted line) (a) and after
(b) a Denker’s approach.
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*
Fig. 26.6 Endoscopic view of a cadaveric left nasal cavity
demonstrating the inferior turbinate (curved white line), septum
(asterisk), middle turbinate (white arrow), and incision at the
piriform aperture for a Denker’s approach (dotted black line).
*
Fig. 26.7 Endoscopic view of a cadaveric dissection
demonstrating a right infraorbital nerve (asterisk) and anterior
wall of the maxilla (white arrow) during a Denker’s approach.
nasopharynx. This will provide a straight line-of-sight
extending to the lateral limits of the infratemporal fossa.
• The mucosa of the posterior wall of the maxillary si-
nus is elevated laterally off the bony wall and may be
preserved for later use during reconstruction if it is not
involved with tumor.
• The posterior wall of the maxillary sinus is then re-
moved using 1- to 2-mm Kerrison rongeurs, Hajek-Koeffler punch, or 45-degree through-biting Blakesley forceps. Dissection continues to a point just lateral to the
inferior orbital fissure.
• The internal maxillary artery and its branches can be
identified anterior to the nerves in the pterygopalatine
fossa and can be ligated to further improve access.
• To permit further lateralization of the contents of the
pterygopalatine fossa, the greater palatine nerve and
artery may be sacrificed or mobilized to permit complete removal of the pterygoid process (Fig. 26.9).
• The vidian nerve is then identified exiting its foramen.
T
he vidian foramen is then exposed and the neurovascular bundle is cauterized with bipolar cautery and then
sharply divided (Fig. 26.10). This allows even further lateralization of contents of the pterygopalatine fossa.
• Dissection may then continue laterally in a subperi-
osteal plane in the pterygopalatine fossa leaving the
soft-tissue contents contained in a sac between the
periosteum of the posterior wall of the maxilla and
the anterior aspect of the pterygoid process. Dissection
in a subperiosteal plane avoids bleeding from the pterygoid arterial and venous plexus. The entire height of
the pterygoid process, foramen rotundum, and maxillary division of the trigeminal nerve are then exposed.
• The vidian canal is then drilled circumferentially in an
anterior-to-posterior fashion toward the petrous ICA.
The vidian nerve crosses lateral to the ICA at the foramen lacerum, and progressive and careful drilling will
avoid inadvertent injury to the ICA.
• Drilling the bone between the vidian nerve and V2
ill lead toward the paraclival ICA, and following the
w
foramen rotundum will lead toward the trigeminal
ganglion. Drilling the inferior wall of the vidian canal,
the pterygoid process, and the medial pterygoid plate
will expose the superior aspect of the ET. The vidian
nerve and ET converge at the lower/fibrocartilaginous
portion of the foramen lacerum and the petroclival
transition of the ICA occupies the upper portion.
• The mandibular branch of the trigeminal nerve (V3) is
located inferior to V2 and anterior to the petrous ICA.
• Once the section of ICA at the foramen lacerum is
identified, bone over the inferior and lateral aspect
of the horizontal petrous ICA may be removed. It is
best to use a hybrid burr when drilling near the ICA
(coarse diamond) as it is less likely to cause injury
than a cutting burr and generates less heat than a
diamond burr, reducing the likelihood of thermal injury to the ICA and surrounding critical structures.
When drilling the carotid canal, the bone is drilled
until it is almost the thickness of an eggshell and
then removed using instruments such as a 1-mm
Kerrison rongeur or fractured off carefully using a
Cottle dissector.
• To obtain distal control of the ICA, the bone overlying
the par
aclival (vertical) ICA may be drilled thin and
removed. Dissection then carefully proceeds along the
ICA using surgical navigation and Doppler sonography
to confirm anatomic landmarks throughout.
• If tumor involves any segment of the ICA, then a tran-
scervical approach could be used in combination with
the expanded endonasal approach (EEA) to gain proximal control of the common, external, and internal carotid arteries. Furthermore, the ICA can be dissected
distally toward the skull base and parapharyngeal ICA
to mobilize away from tumor or to insert a barrier to
identify it and protect it during the EEA.
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*
*
*
Fig. 26.8 Endoscopic view of a cadaveric dissection after a
Denker’s approach and removal of the anteromedial wall of
the maxilla demonstrating the infraorbital nerve (white arrow)
and posterior wall of the maxillary sinus (asterisk).
*
Fig. 26.10 Endoscopic view of the left nasal cavity
demonstrating the vidian nerve (asterisk), V2 (dashed
hemicircle), pterygoid process (black arrow), and the
descending palatine artery (white arrow).
• Removal of the medial pterygoid plate will then expose
the medial third of the ET (Fig. 26.11). This section of
eustachian tube is removed to expose the entire fossa of Rosenmüller and any tumor within and beyond.
Removal of the ET will include removal of the levator
veli palatini and tensor veli palatini muscles.
• The anterior wall of the fossa of Rosenmüller is quite
adherent to the perichondrium of the torus tubarius
and will be removed with the cartilaginous ET.
2,17,29
Fig. 26.9 Endoscopic view of the left nasal cavity demonstrating
the greater/descending palatine artery (black arrow), ascending
process of the palatine bone (black asterisk), medial pterygoid
plate (white arrow), and the eustachian tube (white asterisk).
• Wherever possible, the lateral pterygoid plate is pre-
ser
ved as a landmark for the position of V3 (immediately posterolateral to its base/root) and to protect the
parapharyngeal ICA (posterolateral to V3) (Fig. 26.12).
• To expose the bony ET, the temporalis, medial ptery-
goid, and lateral pterygoid muscles may be displaced or
removed if involved with tumor.
• The posterior and superior aspects of the nasopharynx
are invested in dense fascial tissues and the attachments of the longus capitis muscles. To separate these
soft tissues from the underlying bone, a very sharp dissector and electrocautery are best.
• The tumor is removed en bloc, in layers or sections de-
pending on its size and relationship to critical structures.
• Intraoperative histologic specimens are sent from the
margins (
resection prior to commencing reconstruction.
frozen sections) to confirm the adequacy of
26.4 Reconstruction
Following a complete extirpation, reconstructive options
include a pedicled flap or a free mucosal or acellular
dermis graft. We strongly advocate a pedicled flap in
patients who have undergone radiotherapy or will receive
it postoperatively. A vascularized flap prompts better
and faster wound healing and resists radiation, and will
protect the ICA against exposure and subsequent blowout
from osteoradionecrosis of the surrounding bone. Our
first choice is to use a posterior pedicle nasoseptal flap
in combination with a reverse flap (Caicedo’s reverse
flap30); however, if the septal mucoperiosteum or its
blood supply are not available, our preferred alternative
would be a temporoparietal fascia flap.
A transdural defect is repaired using a multilayer
technique reconstructing the arachnoid layer with an inlay
graft of collagen matrix (e.g., Duragen; Integra LifeSciences
26,27
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Fig. 26.11 Macroscopic photograph of the skull base
demonstrating the relationship between the medial pterygoid
plate (white shaded area), eustachian tube (black line),
foramen ovale (white circle), foramen spinosum (green circle),
and the carotid canal (red circle).
Corp.,). This step is obviated if the resection was extradural
and there is no dural defect. Any dead space that may
impact the reach of the flap may be obliterated with free
fat grafts harvested from the abdomen or as a vascularized
flap rotated in from the buccal fat pad. The nasoseptal flap
is then laid over the defect ensuring enough overlap to
allow for contraction of the flap. We then lay a nonadherent
layer over the flap such as Nasopore (Stryker Corp), gelatin
sponges, or film. We then place expandable nasal sponge
packing, such as Merocel (Medtronic) superficial to the
absorbable material. If the patient required extensive
hemostasis throughout the operation, we will apply
thrombin-soaked gelatin granules (Floseal, Baxter
International) in the region of concern. We have not found
biologic glues to be of any added benefit and therefore do
not use them.
Packing remains in place for 5 to 7 days. Patients use a
saline nasal spray a minimum of three to four times daily
starting day 1 postoperatively. A high-volume, low-flow
saline irrigation three times daily is started upon removal
of the packing.
In patients with dural defects, a postoperative
noncontrasted CT scan is performed within 24 hours
to identify potential complications such as intracranial
hemorrhage or tension pneumocephalus. We also
recommend a contrasted MRI scan within 24 hours
postoperatively to review the completeness of the
resection. This MRI also serves to assess the positioning
of the flap and its vascularity. Nasal debridements are
performed weekly or biweekly for the first 4 to 6 weeks
postoperatively. Thereafter, clinic visits are tailored to the
patient’s needs.
In our clinical environment, postoperative monitoring
includes endoscopic assessment, clinical examination of
the neck, MRI, and PET/CT scanning.
31
A common protocol
would be to perform a PET/CT 3 months after completion
Fig. 26.12 Macroscopic photograph of the skull base
demonstrating the relationship between the lateral pterygoid
plate (blue shaded area), V3 (white circle: foramen ovale), and
the carotid canal (red circle). Green circle, foramen spinosum;
dotted line demonstrates the linear relationship between the
lateral pterygoid plate and the ICA.
of treatment and then at 1 and 2 years of follow-up. MRIs
are performed every 6 months for the first 2 years and then
yearly to complete 10 years of follow-up. The traditional
5-year follow-up may be inadequate in patients who have
received high doses of radiation, as tumor growth may
be slow and not follow the expected pattern. Imaging is
also performed more frequently if there is a questionable
finding. In addition, yearly chest X-rays are recommended
following the second year PET/CT. Circulating cell-free
EBV DNA is a useful molecular marker when monitoring
treatment response but only for those patients who had
positive EBV staining and markers.
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26.5 Discussion
Surgery for nasopharyngeal tumors is difficult due
to their location deep in the central skull base, at least
10 cm from the nasal vestibule, and their intimate
proximity to critical neurovascular structures. The
condition of the tissues in these patients is also challenging,
as many of these patients have failed prior chemoradiation
and thus show severe scarring, radionecrosis, poor
vascularity, and poor healing. Surgical planes and critical
structures may be difficult to delineate. In fact, many times
radionecrosis with secondary bacterial contamination or
infection and tumor seem clinically identical. Emerging
technologies are currently in development to aid in
this distinction and to improve in the early detection
of malignancies. Endoscopic ultrasound may be used
to distinguish malignant tumors from benign lesions
based on flow signals and velocity (rich flow signals
and high velocity are found in malignant tumors).
Advancements in image acquisition technologies include
electronic chromoendoscopy techniques such as narrowband imaging, i-scan, or flexible spectral imaging color
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