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Chapter 36
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36.1 Indications 386
Anterior and Posterior
Pedicle Lateral Nasal
Wall Flaps
36.2 Surgical Steps 386
36.3 Complications 387
36.4 Tips and Tricks 388
Anterior and Posterior Pedicle Lateral Nasal Wall Flaps
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36 Anterior and Posterior Pedicle Lateral Nasal Wall Flaps
Carlos M. Rivera-Serrano, Ricardo L. Carrau
Introduction
In this chapter, the authors describe the indications and
surgical technique to harvest lateral nasal wall pedicle
flaps for endoscopic skull base reconstruction. Important
anatomic landmarks, technical nuances, and surgical
instrumentation are described. In addition, technical tips
and tricks, as well as avoidance of possible complications
in the surgical technique, are emphasized. Clinical
cases and images obtained from cadaveric specimens
are shown to illustrate clinical correlation and facilitate
understanding of the harvesting process.
36.1 Indications
• A successful reconstruction of small skull base defects
seems to be independent of which technique or tissues
are used.
variety of free grafts; however, vascularized flaps promote faster, more reliable healing, thus decreasing complications resulting from a persistent communication
between the sinonasal tract and the cranial cavity.
• Rapid and broad expansion of surgical indications,
diverse clinical scenarios, and increased size and
complexity of surgical defects have triggered the development of new techniques for reconstruction. Various
pedicled flaps have been described for endoscopic skull
base reconstruction within the last decade including
the posterior nasoseptal flap (NSF),
ferior turbinate (IT) pedicled flaps,
terior pedicled lateral nasal wall flaps,
buccinator (FAB) flap,
transpterygoid temporoparietal fascia flap, occipital
galeopericranial flap,
• Skull base surgeons must be versatile regarding dif-
ferent techniques for the approach, resection, and reconstruction. Familiarity with diverse reconstructive
techniques is important, as not all flaps are always
available. The donor site may be compromised during
the approach or extirpative phases of the surgery, by
prior surgery or radiation therapy or may be involved
by tumor. In addition, the defect’s size may require
multiple flaps or combination of techniques.
• In general, reconstruction with the anterior and posteri-
or pedicle lateral nasal wall flaps should be considered
when encountering large cranial base defects and the
use of the NSF is not viable, and the defect appears too
large to be reconstructed with a middle or IT flap. The
advantage of the anterior pedicle lateral nasal wall flap7
and the posterior pedicle nasal wall flap
and hence their name, is that these flaps incorporate
mucosa of lateral nasal wall in addition to the turbinate
itself. These two flaps are not merely slightly extended
IT flaps. Their names denote the fundamental concept
and principle of harvesting as much of the lateral nasal
wall as needed and as possible, even including the nasal
floor mucoperiosteum (extended lateral nasal wall flap).
• More specifically, the posterior pedicle lateral wall flap
is favored in cases where the ipsilateral nasopalatine
artery is available and the defect is posterior to the
1
Large surgical defects can be repaired using a
1,2
3,4
middle5 and in-
6
anterior and pos-
7,8
9
transfrontal pericranial flap,
10
and others.
facial artery
11
8
over an IT flap,
cribriform plate (i.e., planum sphenoidale, sella, and
clivus). The anterior pedicle lateral wall flap is favored
in cases of defects of the anterior two-thirds of anterior
cranial base, or to complement a “short” NSF.
• In brief, the IT and lateral nasal wall receive dual blood
12–14
The posterior blood supply of the IT is main-
y.
suppl
ly a terminal branch of the posterolateral nasal artery
(branch of the sphenopalatine artery).
supply originate from the angular artery,
ethmoidal artery, and other intranasal vessels.
2
The anterior
2,15,16
anterior
14
36.2 Surgical Steps
Incisions may be made with a monopolar electrocautery
fitted with an extended, insulated, needle tip
(Arthroscopic electrode; Valley Laboratory, Boulder,
CO) or an extended Colorado tip (Stryker Corporation,
Kalamazoo, MI). Alternatively, the mucoperiosteum
can be incised with a Cottle elevator or any other sharp
instrument of preference.
36.2.1 Common Incision for Both
Lateral Nasal Wall Flaps
The anterior and posterior lateral nasal wall flaps
share some common incisions and therefore there are
similarities in the harvesting technique of these flaps.
The common incisions are the anteroinferior, superior,
and posterior incisions (Figs. 36.1, 36.4). In the posterior
pedicle lateral wall flap, an anteroinferior incision is also
made, whereas in the anterior pedicle lateral wall flap this
tissue is preserved, as it will be the pedicle of the flap.
On the other hand, in the anterior pedicle lateral wall
flap, a posterior incision is made (area of sphenopalatine
vessels), whereas in the posterior pedicle lateral wall flap
this area is preserved as its pedicle.
The superior incision starts somewhat vertically
and follows the posterior aspect of the lacrimal bone
(i.e., unguis) or nasomaxillary line, just anterior to the
uncinate process. This incision is then curved posteriorly
at the superior aspect of the inferior turbinate, continuing
posteriorly along the superior aspect of the turbinate
until reaching the sphenopalatine area. Posterior to the
uncinate process, the incision can migrate cephalad
to incorporate the fontanelle of the maxillary sinus.
Alternatively, a maxillary antrostomy can be made to
facilitate the previously described incision. Resection
of the middle turbinate is not necessary, but it greatly
facilitates the incisions and harvesting process. At the
most posterior aspect of this incision, the sphenopalatine
foramen and some of its arteries will be encountered.
The anteroinferior incision starts at the caudal edge of
the nasal bones and then travels inferiorly and posteriorly
toward the head of the inferior turbinate. Once it reaches
the lowest point of the head of the inferior turbinate, it
curves laterally to travel in a posterior direction (sagittal
direction), now in the inferior meatus, until reaching
the nasolacrimal duct opening (Fig. 36.2). The orifice
of the nasolacrimal duct is preserved by continuing
386
Ant-Inf
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incision
Superior
incision
Inferior incision
MT
IT
Anterior and Posterior Pedicle Lateral Nasal Wall Flaps
Fig. 36.1 Anterior pedicle lateral
nasal wall fl ap. Representation of the
right lateral nasal wall demonstrating
the incisions needed to harvest the
anterior pedicle lateral nasal wall fl ap.
The three common incisions with
the posterior pedicle lateral nasal
wall fl ap are depicted. These are the
anteroinferior, superior, and inferior
(in magenta intermittent lines). The
unique incision in this fl ap is the
posterior incision (pointed with an
arrow). The curved arrows point the
pedicle/vascular fl ow of the fl ap.
Please note that the anteroinferior
ST
Posterior
incision
incision is directed laterally (from
the head of the inferior turbinate)
toward the metal side of the inferior
turbinate/nasolacrimal duct opening
(correlate with Fig. 36.2), to
incorporate the lateral–inferior nasal
mucosal wall of the middle meatus.
This part of the incision is shown
with a lighter color. For additional
clarifi cation, the medial aspect of the
inferior turbinate is not incised. The
white arrow points to the orifi ce of the
nasolacrimal duct (the anteroinferior
incision needs to be curved around
the orifi ce of the nasolacrimal duct).
The small black arrow points toward
the extension of the fl ap on the nasal
fl oor. IT, inferior turbinate; MT, middle
turbinate; ST, superior turbinate.
the incision in the most medial/cephalic aspect to the
orifice. After sparing the opening of the duct, the incision
continues inferiorly on the lateral wall of the inferior
meatus, eventually reaching the nasal floor. The incision
can potentially continue medially (across the nasal floor;
coronal plane) until reaching the septum. Alternatively, the
incision can go straight down from the axilla of the middle
turbinate to incorporate additional meatal mucosa and
nasal floor into the flap (Fig. 36.3); however, the mucosa
around the lacrimal duct should be preserved, with the
disadvantage of having to create a perforation (“button
hole”) to elevate the flap off the duct opening. Frequently,
a small incision needs to be carried slightly into the first
few millimeters of the turbinate (head) itself, to facilitate
later turbinate “unfolding” and bone removal (Fig. 36.2).
The inferior incision connects the most inferior (or
inferomedial if the incision is extended to the nasal floor)
aspect of the anteroinferior incision and the most inferior
(or inferomedial) aspect of the posterior incision in the
anterior pedicle lateral wall flap, or the most inferior (or
inferomedial) aspect of the anteroinferior incision and
pedicle of the posterior pedicle lateral wall flap.
36.2.2 Additional Incisions
Anterior pedicle lateral wall flap: a posterior incision is
made at the back end of the inferior turbinate/lateral
nasal wall (and nasal floor if included in the flap) in
the area of the sphenopalatine vessels, connecting the
superior and inferior incisions (Fig. 36.1). Control of the
sphenopalatine artery requires cauterization or clipping
of its anterior and inferior branches. A monopolar suction
cautery, endoscopic bipolar, or clip applier can be used
for this purpose.
Posterior pedicle lateral wall flap: an anterosuperior
incision is made to connect the superior and anteroinferior
incisions as high as possible in the area of the nasal
bones (Fig. 36.4). In this flap, the posterior incision is
omitted; however, the most medial aspect (nasal floor)
of this incision can still be made to facilitate rotation/
transposition of the flap.
36.2.3 Flap Elevation and Additional
Technical Details
It is useful to “greenstick” fracture the inferior turbinate
medially, so that it remains perpendicular to the lateral
nasal wall, as this facilitates the visualization and elevation
of the meatal mucoperiosteum. The mucosa of the medial
and lateral (meatal) aspects of the inferior turbinate is
elevated with a Cottle elevator, and the residual turbinate
bone is removed with rongeurs, through-cutting
instruments, or other instrument of preference.
The mucoperiosteum of the lateral aspect of the inferior
turbinate (meatal side) is elevated until it joins the lateral
nasal wall at the level of the opening of the nasolacrimal
duct. The lateral nasal wall (middle fontanelle) and
inferior meatus mucoperiosteum are then elevated
posteriorly toward the palatine bone (Fig. 36.3).
387
Anterior and Posterior Pedicle Lateral Nasal Wall Flaps
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a
c
Fig. 36.2 Anterior pedicled lateral nasal wall fl ap. (a) Anteroinferior incision = red intermittent line. Superior incision = white
intermittent line. Note how the most inferior aspect of the anteroinferior incision is continued (curved white arrow) on the meatal
side to incorporate the lateral–inferior nasal mucosal wall of the middle meatus. (b) The turbinate bone has been removed with
Kerrison rongeurs (not shown), and the incision is continued on the metal side toward the nasolacrimal duct opening (smaller red
intermittent line). If the turbinate head hangs lower than the nasal wall, an incision over the head of the inferior turbinate is made
and connected to the main anteroinferior incision. This additional incision should be extended as inferiorly as possible to facilitate
later turbinate “unfolding” and bone removal; this area is pointed with an elevator. Otherwise, the turbinate mucoperiosteum will not
unfold, thus retaining the shape of the turbinate. (c) The incision shown in (b) is completed with endoscopic scissors. (d) The incision
(red intermittent line) is curved around the opening of the lacrimal duct (white arrow) and then continued inferiorly. Alternatively,
the incision can go straight down from the axilla of the middle turbinate to incorporate additional meatal mucosa and nasal fl oor
into the fl ap; however, the mucosa around the nasolacrimal duct should be preserved, with the potential disadvantage of creating
a perforation (“button hole”) in the fl ap.
b
d
Finally, the nasal floor mucosa is elevated (Fig. 36.3).
As with the posterior pedicle inferior turbinate flap, the
mucoperiosteum of the turbinate tends to retain the
shape of the turbinate. It is useful to stretch and flatten
the turbinate using a bimanual technique as the flap is
transposed.
In terms of the posterior pedicle lateral wall flap,
special attention should be taken at the most posterior
aspect of the flap, as branches of the sphenopalatine
artery, especially the posterolateral nasal artery, should
be preserved. Once elevated, the flap may be transposed
with a pivot point at the sphenopalatine foramen (Fig.
36.4), or alternatively preserving a wider pedicle along
the nasal floor. However, a wider pedicle produces
more torque and retraction. Due to its pivot point, its
pedicle may need to be freed from the sphenopalatine
foramen. This will facilitate a greater degree of rotation/
transposition.
388
In terms of the anterior pedicle lateral wall flap, its paddle
can be transposed superiorly and posteriorly. Its pivot
point will be the superior aspect of the ascending process
of the maxilla/upper aspect of the nasal bones (Fig. 36.1).
36.3 Complications
• Transient morbidity is similar to one produced by the
harvesting of other nasal mucosal flaps, including post-
operative epistaxis and nasal crusting. In the anterior
pedicle lateral wall flap, particular attention should be
paid to clip or cauterize branches of the sphenopala-
tine artery. Nasal crusting should resolve with time un-
til remucosalization occurs. Appropriate postoperative
care should include measures to enhance nasal mois-
ture (e.g., nasal sprays). A series of postoperative out-
patient visits may be needed for office debridements.
Anterior and Posterior Pedicle Lateral Nasal Wall Flaps
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a
b
dc
e
Fig. 36.3 Anterior pedicled lateral nasal wall fl ap. (a) Intermitted red line = continuation of the anteroinferior incision into the lateral
nasal wall (inferior meatus) and then into the nasal fl oor. (b) The inferior (sagittal) incision (black intermitted arrow) is made along
the nasal fl oor and joins the anteroinferior incision (red intermittent line). (c) The fl ap is elevated posteriorly. The intermitted red line
represents the location of the anteroinferior incision, which is extending into the nasal fl oor. (d) The fl ap is further elevated all the
way to the area of the sphenopalatine vessels. The red intermittent line represents the anteroinferior incision. Note how this incision
curves fi rst into the meatal side and then around the opening of the lacrimal duct (white arrow), fi nally continuing inferiorly into
the nasal fl oor. The green intermittent line represents an alternative incision that goes straight down from the axilla of the middle
turbinate to incorporate additional meatal mucosa and nasal fl oor into the fl ap; however, the mucosa around the lacrimal duct should
be preserved, with the potential disadvantage of creating a perforation (“button hole”) in the fl ap. (e) The fl ap is almost completely
elevated. The black arrow points at the pedicle. (f) The fl ap is transposed superiorly into the anterior cranial base. In the fi gure, a wide
septectomy was performed. The black arrow represents the superior aspect of the nasal septum at the skull base.
f
389
Anterior and Posterior Pedicle Lateral Nasal Wall Flaps
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Ant-Sup
incision
Superior
incision
MT
Ant-Inf
incision
Nasal floor
component
Inferior incision
IT
Fig. 36.4 Posterior pedicle lateral
nasal wall fl ap. Representation of the
right lateral nasal wall demonstrating
the incisions needed to harvest the
posterior pedicle lateral nasal wall
fl ap. The three common incisions
with the posterior pedicle lateral
nasal wall fl ap are depicted. These
are the anteroinferior, superior, and
inferior (in magenta intermittent
lines). The unique incision in this
fl ap is the anterosuperior incision
(pointed with an arrow). The small
curved arrows point the pedicle/
vascular fl ow of the fl ap. Please note
that the anteroinferior incision is
directed laterally (from the head of
ST
the inferior turbinate) toward the
metal side of the inferior turbinate/
nasolacrimal duct opening (correlate
with Fig. 36.2), to incorporate the
lateral–inferior nasal mucosal wall of
the middle meatus. This part of the
incision is shown in a lighter color.
For additional clarifi cation, the medial
aspect of the inferior turbinate is not
incised. The white arrow points to the
opening of the nasolacrimal duct on
the meatal side (the anteroinferior
incision needs to be curved around
the opening of the lacrimal duct).
The small gray arrow points toward
the extension of the fl ap on the nasal
fl oor. IT, inferior turbinate; MT, middle
turbinate; ST, superior turbinate.
Dashed black (circles) line and small
black arrow: an incision can be made
at the nasal fl oor to increase the arc of
rotation of the fl ap.
• A potential unique complication from the harvesting of
these flaps is injury to the orifice of the nasolacrimal
duct. Stenosis may occur if the mucosa around the duct
opening is not preserved or handled with care. However, this is a theoretical complication, as we have not
seen it in practice.
36.4 Tips and Tricks
• Nasal decongestion with nasal pledgets soaked with a
1:10000 epinephrine solution and/or selective injections of lidocaine 0.5 to 1.0% with 1:50,000–200,000
epinephrine into the proposed incisions sites will help
to decrease bleeding and improve visualization.
• Incisions made with a monopolar electrocautery fitted
with an extended, insulated, needle tip (Arthroscopic
electrode, Valley Laboratory, Boulder, CO), or an extended Colorado tip (Stryker Corporation, Kalamazoo,
MI) will also decrease operative bleeding. We have not
seen problems or flap losses from the use of electrocautery or epinephrine in clinical practice.
• The incisions can be made in any order; however, it is
generally easier to make the lower incisions first, to
minimize the downstream pooling of blood that may
intermittently obscure the surgical field.
390
• Carrying the incisions down to bone with a single pass
greatly facilitates the speed of harvesting.
• As with any intranasal flaps, it is easier to elevate the
flaps from their beds using an anterior to posterior
motion.
• Make sure that the incision over the head of the inferior
turbinate is extended as low as possible in cases where
the most inferior aspect of the head of the turbinate
hangs lower than the nasal wall; otherwise, the turbinate mucoperiosteum will not unfold, thus retaining
the shape of the turbinate. Note how in Figs. 36.2 and
36.3 the head of the inferior turbinate is flush with the
lateral nasal wall.
• “Greenstick” fracturing the turbinate helps to visu-
alize that part of the flap in the area of the inferior
meatus; however, it may be easier to first dissect the
mucoperiosteum from the turbinate bone as much
as possible while the bone is fixed to the nasal wall,
then in- fracture its bone, and then remove the bone
fragments.
• A temporary bolster using some type of nasal packing
w
ill help to fixate the flaps and avoid the tendency of
the inferior turbinate portion of the flap to maintain
its original/anatomic shape, and therefore maintain the
turbinate “unfolded.”
Anterior and Posterior Pedicle Lateral Nasal Wall Flaps
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• Resection of the middle turbinate is not necessary,
but it greatly facilitates the incisions and harvesting
process.
• As previously stated, part of the fontanelle can
be incorporated into the flap, thus increasing the
flap width.
References
1. Hegazy HM, Carrau RL, Snyderman CH, Kassam A, Zweig J. Trans-
nasal endoscopic repair of cerebrospinal fluid rhinorrhea: a
meta-analysis. Laryngoscope 2000;110(7):1166–1172
2. Fortes FS, Carrau RL, Snyderman CH, et al. The posterior pedicle
inferior turbinate flap: a new vascularized flap for skull base
reconstruction. Laryngoscope 2007;117(8):1329–1332
3. Hadad G, Bassagasteguy L, Carrau RL, et al. A novel reconstructive
technique after endoscopic expanded endonasal approaches: vascular pedicle nasoseptal flap. Laryngoscope 2006;116(10):1882–
1886
4. Rivera-Serrano CM, Snyderman CH, Gardner P, et al. Nasosep-
tal “rescue” flap: a novel modification of the nasoseptal flap
technique for pituitary surgery. Laryngoscope 2011;121(5):
990–993
5. Prevedello DM, Barges-Coll J, Fernandez-Miranda JC, et al. Middle
turbinate flap for skull base reconstruction: cadaveric feasibility
study. Laryngoscope 2009;119(11):2094–2098
6. Harvey RJ, Sheahan PO, Schlosser RJ. Inferior turbinate pedicle
flap for endoscopic skull base defect repair. Am J Rhinol Allergy
2009;23(5):522–526
7. Hadad G, Rivera-Serrano CM, Bassagaisteguy LH, et al. Anterior pedicle lateral nasal wall flap: a novel technique for the
reconstruction of anterior skull base defects. Laryngoscope
2011;121(8):1606–1610
8. Rivera-Serrano CM, Bassagaisteguy LH, Hadad G, et al. Posterior pedicle lateral nasal wall flap: new reconstructive technique for large defects of the skull base. Am J Rhinol Allergy
2011;25(6):e212–e216
9. Rivera-Serrano CM, Oliver C, Prevedello D, et al. Pedicled Facial
Buccinator (FAB) flap: a new flap for reconstruction of skull base
defects. Laryngoscope 2010;120(Suppl 4):S234
10. Rivera-Serrano CM, Snyderman CH, Carrau RL, Durmaz A, Gardner
PA. Transparapharyngeal and transpterygoid transposition of a
pedicled occipital galeopericranial flap: a new flap for skull base
reconstruction. Laryngoscope 2011;121(5):914–922
11. Oliver CL, Hackman TG, Carrau RL, et al. Palatal flap modifications
allow pedicled reconstruction of the skull base. Laryngoscope
2008;118(12):2102–2106
12. Babin E, Moreau S, de Rugy MG, Delmas P, Valdazo A, Bequignon A.
Anatomic variations of the arteries of the nasal fossa. Otolaryngol
Head Neck Surg 2003;128(2):236–239
13. Lee HY, Kim H-U, Kim SS, et al. Surgical anatomy of the
sphenopalatine artery in lateral nasal wall. Laryngoscope
2002;112(10):1813–1818
14. Padgham N, Vaughan-Jones R. Cadaver studies of the anatomy of arterial supply to the inferior turbinates. J R Soc Med
1991;84(12):728–730
15. Murakami CS, Kriet JD, Ierokomos AP. Nasal reconstruction using the inferior turbinate mucosal flap. Arch Facial Plast Surg
1999;1(2):97–100
16. Penna V, Bannasch H, Stark GB. The turbinate flap for oronasal
fistula closure. Ann Plast Surg 2007;59(6):679–681
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Chapter 37
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37.1 Anatomy of the Frontal and
Temporal Scalp 394
Pericranial and
Temporoparietal
Fascia Flaps
37.2 Transfrontal Pericranial Flap 394
37.3 Transpterygoid
Temporoparietal Fascia Flap 397
37.4 Discussion 400
Pericranial and Temporoparietal Fascia Flaps
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37 Pericranial and Temporoparietal Fascia Flaps
Raewyn G. Campbell, Hafi z Patwa, Bradley A. Otto, Daniel M. Prevedello, Ricardo L. Carrau
Introduction
It has been well established that vascularized flaps are
the best reconstructive options in preventing postoperative cerebrospinal fluid (CSF) leak in patients with large
skull base defects, high intracranial pressure (>30 cm
H20), widely dissected arachnoid cisterns, and extensive
removal of dura. While intranasal flaps, specifically, the
posteriorly based nasoseptal flap has become the workhorse flap in endoscopic skull base reconstructions, there
are still occasions where extranasal pedicled flaps are
needed for reconstruction.
Extranasal pedicled flaps may be used in situations
where the vascular supply to the nasoseptal flap, or other
local regional intranasal flaps, has been compromised or
when multiple flaps are needed for the reconstruction.
Other potential circumstances when these flaps may be
necessary include neoplastic involvement of intranasal
tissue that would otherwise be used as a flap or previous
use of flaps (e.g., recurrent tumor). In this chapter, we describe two extranasal pedicled flaps: the transpterygoid
temporoparietal fascia (TPF) flap and the transfrontal
pericranial flap. Indications, contraindications, and surgical technique will be discussed in detail.
1
37.1 Anatomy of the Frontal
and Temporal Scalp
Elevation of the pericranial and temporoparietal flaps
requires a thorough understanding of the anatomy of the
scalp. The scalp is divided into five layers. From superficial
to deep, these layers comprise the following:
• Skin.
• Subcutaneous layer.
• Aponeurotic layer includes the galea and frontalis mus-
cle anteriorly, the occipitalis muscle posteriorly, and
the TPF laterally.
• Subaponeurotic layer comprises of loose areolar tissue.
• The periosteal layer on the frontal scalp is contiguous
with the superficial layer of the deep temporalis fascia,
which overlies the temporalis muscle.
Pericranium is a surgical term defined as a combination of
the periosteal and the subaponeurotic layers (i.e., areolar
tissue).
37.2 Transfrontal Pericranial
Flap
The transfrontal pericranial flap is a regional pedicled
flap comprising the ipsilateral anterior pericranium,
which is pedicled on the ipsilateral supraorbital (and
sometimes the supratrochlear) neurovascular bundle.
This flap has been used extensively in skull base reconstruction after anterior craniofacial resection (usually
using both sides of the frontal pericranium and their
corresponding neurovascular pedicle) with excellent
outcomes.
2–4
37.2.1 Indications
When considering defects after endoscopic skull base
surgery, this flap is most useful to reconstruct large anterior skull base defects when intranasal pedicled flaps
are not available or when multiple flaps are required (i.e.,
to cover defects extending from the frontal sinus to the
clivus and from orbit to orbit).
5
37.2.2 Contraindications
Careful consideration should be given to any patient who
has undergone prior open cranial surgery, particularly via
a subfrontal approach, a brow lift, or any patient who has
suffered orbital rim fractures.
37.2.3 Anatomy
A transfrontal pericranial flap is based on the supraorbital
and supratrochlear neurovascular bundles, and therefore,
the frontal pericranium can be harvested as two separate flaps. The supratrochlear and supraorbital nerves
are cutaneous branches of the ophthalmic division of
the trigeminal nerve. The supratrochlear nerve supplies
the midline forehead to the hairline and the supraorbital
nerve supplies the forehead and scalp extending back to
the vertex.
are branches of the ophthalmic artery, which branches
from the supraclinoid segment of the internal carotid artery as it emerges from the roof of the cavernous sinus.
The supratrochlear artery emerges through the frontal
notch or foramen as part of the neurovascular pedicle.
The supratrochlear notch (or foramen), which is medial
to the supraorbital notch (or foramen), which lies approximately 22.2 mm from the midline.
A supraorbital notch (as opposed to a foramen) is most
common, being present in approximately 70% of cadaveric specimens. Conversely, a foramen is found in approximately 30% of specimens.
frontalis muscular layer providing branches that supply
the pericranium.
injury to the neurovascular pedicle during the elevation of
the pericranial flap, the frontalis muscle layer should not
be separated from the pericranium closer than 10 mm of
the orbital rim.
arteries anastomose with each other and with the superficial temporal artery, a terminal branch of the external
carotid artery, thereby forming anastomoses between the
internal and external carotid arterial systems.
37.2.4 Surgical Steps
1. The nasal cavity is decongested with cottonoids im-
6
The supratrochlear and supraorbital arteries
7
7
The arteries ascend in the galea
2
It is important to remember that to avoid
2
Both the supraorbital and supratrochlear
8
pregnated with a solution of 1:10,000 epinephrine.
This aids with hemostasis throughout the surgery.
At the beginning of surgery, the lateral nasal wall is
infiltrated with a solution of lidocaine 0.5 to 1% with
epinephrine 1:100,000.
6
394
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