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Posterior Pedicle Lateral Nasal Wall Flap:
New Reconstructive Technique for Large Defects of the Skull Base
Carlos M Rivera-Serrano, MD1
Luis H. Bassagaisteguy, MD 2
Gustavo Hadad, MD 2
Ricardo L Carrau, MD 3
Dan Kelly, MD 4
Daniel M. Prevedello, MD 5
Juan Fernandez-Miranda, MD 6
Amin B Kassam, MD 7
1Department of Otolaryngology-Head and Neck Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA
2 Department of Otolaryngology-Head & Neck Surgery, Medical School of Ciudad de Rosario,
Provincia de Santa Fe, Republica Argentina
3Department of Otolaryngology-Head & Neck Surgery The Ohio State University, Columbus, OH
4 Brain Tumor Institute, Department of Neurosurgery
John Wayne Cancer Institute, Santa, Monica, CA
5Department of Neurosurgery, The Ohio State University, Columbus, OH
6Department of Neurological Surgery,
University of Pittsburgh Medical Center, Pittsburgh, PA
7Department of Neurosurgery, University of Ottawa, Ottawa, CA
Financial Disclosure: -No funding support was required for the completion of this manuscript. -None of the authors have financial interests in companies or other entities that have an interest in the information in the contribution.
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Conflict of Interest: None
-This material has never been published and is not currently under evaluation in any other peer-reviewed publication. This material has not been presented.
Key words: Endoscopic approach, reconstruction, nasal, endonasal, skull base surgery, CSF leaks, reconstructive flap, pedicle flap, lateral wall of the nose
Corresponding author: Ricardo L. Carrau, M.D., F.A.C.S. Professor Department of Otolaryngology-Head & Neck Surgery The Ohio State University Medical Center 915 Olentangy River Road Suite 4000 Columbus, OH 43212 [email protected] [email protected]
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Abstract Background: Indications for expanded endoscopic approaches continue to grow, resulting in
larger and more complex skull base defects. Reconstructive developments, however, have lagged
our extirpative capabilities. As the complexity of clinical scenarios continues to escalate,
challenging our current reconstructive strategies, we are compelled to develop alternative
techniques to prevent CSF leaks and protect neurovascular structures.
Objectives: In this article we demonstrate the anatomical basis for a new posterior pedicled flap
from the lateral wall of the nose (Carrau-Hadad or C-H flap) for the reconstruction of median
skull base defects, and present our early clinical experience.
Methods: Using a cadaveric model we designed a posterior pedicle flap comprising the nasal
inferolateral wall mucoperiosteum. We applied this information clinically, to reconstruct
transmural skull base defects.
Results: In our cadaveric model, we harvested and transposed C-H flaps into various defects of
the planum sphenoidale, sella turcica, clivus and nasopharynx. Then, we used the C-H flap in
four patients, successfully reconstructing their clival (n=3) and sellar (n=1) surgical defects. All
patients healed uneventfully.
Conclusions: Our anatomical study and early clinical experience support the use of the posterior
pedicle lateral nasal wall flap to reconstruct large cranial base defects resulting from endoscopic
skull base surgery in properly selected patients.
Level of Evidence: 2B
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INTRODUCTION:
A favorable outcome is expected following the endoscopic reconstruction of small
defects of the skull base, regardless of which technique or tissue is used; therefore, vascularized
flaps do not appear to be essential for the reconstruction of limited defects.1 In contrast, the use
of vascularized flaps for the reconstruction of large skull base defects, regardless of the surgical
approach (open or endoscopic) seems to be advantageous. Some have obtained adequate results
with the use of free tissue grafts such as fat, acellular dermis or fascia lata. Free grafts still are an
important part of our armamentarium (specially when a pedicle flap is not available). However,
vascularized flaps lead to faster and more reliable healing; thus, they are associated with a lower
risk of postoperative CSF leaks and their associated complications.2-9
Skull base defects resulting from expanded endonasal approaches (EEA) can be
extremely challenging to reconstruct due to their complexity and extent. Development of
reconstructive strategies have lagged that of extirpative techniques; thus, presenting a major
hurdle toward standardization and popularization of EEA.2-5 During the last five years, various
endonasal pedicled flaps have been developed, including the Hadad-Bassagasteguy nasoseptal
flap, and middle and inferior turbinate pedicled flaps.6-8 These flaps represent important
advancements that helped to decrease the incidence of postoperative CSF leaks to less than 5%.10
Availability, versatility and reliability have propelled the rapid popularization of the
Hadad-Bassagasteguy nasoseptal flap; however, tumor extension or prior surgery, involving the
nasal septum, rostrum of the sphenoid sinus or pterygopalatine fossa, may preclude its use. In
addition, the extent of the defect may require the use of multiple flaps, or a hybrid technique
combining vascularized flaps and free tissue grafts.2-5 Hence, current reconstructive algorithms
demand alternative reconstructive strategies.
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Following the patterns of nasal blood supply (“vascular tree”) one can design other
potential pedicled vascular flaps. We have benefited from the work of others, who have
characterized the vascular anatomy of the lateral nasal wall.11-17 Blood supply of the postero-
lateral nasal wall mainly originates from the sphenopalatine artery, a terminal branch of the
internal maxillary artery.11-14 The inferior turbinate, however, has a dual anterior and posterior
blood supply; although, its main blood supply arises posteriorly from the posterolateral nasal
artery (a branch of the sphenopalatine artery). 6, 13-15 We have taken advantage of this anatomical
attribute that serves as the foundation of our new reconstructive technique. In this article, we
describe an innovative pedicled flap comprising the mucoperiosteum of the infero-lateral wall
and floor of the nasal cavity, the Carrau-Hadad (C-H) flap, based posteriorly on branches of the
sphenopalatine artery. We demonstrate its anatomical basis using a cadaveric model and further
establish its feasibility with our early clinical experience.
MATERIALS AND METHODS
Our anatomical dissections were, completed at the Medical School of Rosario (Province
of Santa Fe, Argentina) and were reproduced at the Minimally Invasive Neurosurgery Center
(MINC) anatomy labs at the University of Pittsburgh Medical Center (approved by the
Committee for Oversight of Research Involving the Dead or CORID). Three fresh and five
preserved cadaveric specimens were used to design, harvest and transpose several modifications
of the C-H flap into various defects of the median skull base (see following description). To
better evaluate the vascular anatomy, we injected the specimens with colored silicone, using red
for the arterial system and blue for the venous system.18 Anatomic details and technical
variations revealed by the cadaveric model provided us with enough confidence to use the C-H
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flap clinically. Therefore, we used the C-H flap to reconstruct four patients, who required EEAs
at the John Wayne Cancer Institute (Santa Monica, CA) and the Instituto de Diagnostico y
Cirugia: Cabeza y Cuello, Nariz y Senos Faciales, Base Anterior de Craneo (Rosario, Argentina);
and, whose clinical presentation prohibited the use of the Hadad-Bassagasteguy nasoseptal flap
(HBF). Pertinent clinical data was reviewed retrospectively (IRB exemption granted).
Surgical Technique
Endonasal incisions can be made with a unipolar electrocautery fitted with an extended,
insulated needle tip (Valleylab, Boulder, Colorado) or a Colorado tip (Stryker Corporation,
Kalamazoo, MI). However, any sharp instrument may be adequate. Anteriorly, the
mucoperiosteum is incised along the anterior border of the ascending maxillary process, starting
at a level that corresponds to the most caudal aspect of the nasal bones and extending inferiorly
to the level of the head of the inferior turbinate (Figures 1 and 2). A second vertically oriented
incision is made along the posterior aspect of the lacrimal bone, starting at a level that is superior
to the anterior insertion (“axilla”) of the middle turbinate, and extending inferiorly to a level near
the upper aspect of the inferior turbinate. A third incision connects the most superior aspect of
the first two incisions.
According to the needs of each case, the anterior incision may extend further inferiorly
along the lateral nasal wall, just anterior to the inferior turbinate, and continue over the floor of
the nasal cavity to harvest a wider flap (Figures 1 and 2D). At its most infero-medial level, it
joins another incision (oriented in the sagittal plane), which extends posteriorly to a point that is
at the level of the sphenopalatine foramen (in the coronal plane; Figures 1, 2D). As previously
mentioned, this latter incision can be placed at the lateral nasal wall or carried medially over the
floor of the nose, to harvest a wider flap. The incision over the lacrimal bone (antero-posterior)
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joins a sagittal incision that extends posteriorly, over the superior aspect of the inferior turbinate,
to reach the sphenopalatine foramen. Some of the mucosa of the maxillary sinus fontanelle can
be incorporated into this incision to widen the surface area of the flap. Alternatively, this incision
can be part of a wide maxillary antrostomy. Resection of the middle turbinate greatly facilitates
the visualization and harvest of the flap, but is not mandatory. Another horizontal incision
crosses the floor of the nose at the level of the sphenopalatine foramen (in the coronal plane) to
connect the superior and inferior sagittal incisions, (Figures 1).
The head of the inferior turbinate is incised vertically and the incision is extended to
intersect the most anterior incision. This incision at the head of the turbinate is critical to harvest
the meatal aspect of the inferior turbinate mucoperiosteum (Figure 2E). The mucoperiosteum is
dissected with a Cottle or Freer periosteal elevator (Figure 2B), continuing its dissection along
the medial (nasal) aspect of the inferior turbinate bone. The bone may be sequentially removed
with true-cut and Kerrison rongeurs or any other preferred instrument (Figure 3A); and the
mucoperiosteum of the lateral (meatal) side is elevated, until it curves laterally at the level of the
opening of the nasolacrimal duct (Figures 3B and C). The opening of the nasolacrimal duct and
Hasner’s valve is preserved by incising around its periphery; thus, preserving it in situ (Figures
3D-F).
The mucoperiosteum is elevated further posteriorly along the lateral nasal wall (inferior
meatus and fontanelle) and the remaining floor of the nose component. (Figure 4). Special care
should be taken at the most posterior aspect of the flap, as the branches of the sphenopalatine
artery, especially the postero-lateral nasal artery, should be identified and preserved (Figure 4A).
Once elevated, the flap may be rotated posteriorly or superiorly with a pivot point at the
sphenopalatine foramen, or preserving a wider base that extends to the inferolateral nasal wall to
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the junction of the hard and soft palates (Fig 5). Due to its pivot point, its pedicle may needs to
be freed from the sphenopalatine foramen. This facilitates a rotation of up to 1800 from its
original position.
A temporary bolster using nasal packing helps to fixate the flap. As long as the pedicle is
free, its rotation does not cause significant retraction of the flap away from the defect. However,
a wider pedicle (extended to the floor of the nose) produces more torque and retraction. The C-H
flap dimensions were adequate to reconstruct the expanse from nasopharynx to planum
sphenoidale (antero-posterior), and from orbital apex to orbital apex or ICA canal to ICA canal
(latero-lateral).
RESULTS
In the cadaveric model, all C-H flaps were harvested using the previously described
technique and modifications, and were uneventfully transposed into a myriad of defects of the
median skull base. The PLNA and its inferior turbinate branch were routinely identified and
preserved during the harvesting of the flap. The C-H flap appeared to be adequate to reconstruct
defects of the planum sphenoidale, sella, clivus and nasopharynx. The only challenge was a
tendency for the inferior turbinate portion of the flap to return to its original shape.
Clinically, C-H flaps were used for the reconstruction of four patients whose presentation
prohibited the use of the Hadad-Bassagaisteguy nasoseptal flap. Three patients underwent a
trans-clival resection for recurrent clival chordomas that had been previously treated with
surgery and radiotherapy. One patient underwent an expanded endonasal resection for a recurrent
pituitary extrasellar adenoma that produced a large CSF leak. Harvesting of the flaps proceeded
in a fashion similar to our experience in the anatomical laboratory. All flaps appeared viable after
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harvesting, without discoloration or congestion. All four surgical defects were successfully
reconstructed with C-H flaps, which were transposed in place and fixated with a multilayer
bolster using gelatin sponges, tissue sealant, and strip-gauze or sponge packing (removed five
days after surgery). No perioperative lumbar spinal drain was used in any of the patients.
Postoperative viability and uneventful healing of the C-H flaps and nasal cavity were monitored
during the postoperative follow up visits. All patients required daily nasal toilette that included
self-administered saline lavages and moisturizing sprays; and, weekly or bi-weekly office
debridement for 6-8 weeks postoperatively. However, all four patients healed uneventfully with
no CSF leak or any other postoperative complication (Figure 6).
DISCUSSION
During the past two decades, we have witnessed the evolution of endoscopic endonasal
approaches, from trans-sphenoidal surgery for sellar lesions to expanded endonasal approaches
(EEA) for a variety of pathologies located along the ventral skull base.2-5 Their use to manage
skull base lesions has increased exponentially. Reconstructive developments, however, have
lagged our extirpative capabilities, and increasingly complex clinical scenarios continue to
challenge current reconstructive strategies.
Reconstructive objectives after resection of the skull base include protection of critical
neurovascular structures and separation of the cranial cavity from the sinonasal tract2-4; therefore,
decreasing the risk of postoperative cerebrospinal fluid (CSF) leaks and ascending bacterial
infections.1 An hermetic separation of cranial cavity and sinonasal tract also protects major
vessels against desiccation and infection that could lead to a vascular blow-out or
pseudoaneurysm.
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It has been demonstrated that repair of small CSF fistulas is successful in over 95% of
cases, independent of which biological tissue or surgical technique is used.1 Some have obtained
good results with the use of free grafting for the reconstruction of defects after endoscopic skull
base surgery. However, others have reported that the incidence of postoperative CSF leaks
increases significantly when free grafting techniques are used to reconstruct large cranial base
defects.2, 5, 8, 10
Pedicled mucosal and fascial flaps provide the most reliable, reproducible and optimal
reconstruction of large skull base defects. Reconstruction of skull base surgery defects using
vascularized tissue is associated with a significantly lower incidence of postoperative CSF leaks.
In our experience, the HBF posterior pedicle nasoseptal flap lead to a dramatic improvement in
our postoperative CSF leaks rate, currently less than 5%.4, 8, 10 However, the HBF is frequently
not available in patients who have undergone previous posterior septectomy or wide
sphenoidotomies, which compromise its pedicle; or when the donor site (nasoseptal mucosa) is
infiltrated by tumor. As a result, alternative endonasal reconstructive flaps have been developed;
however, these are yet not sufficient to provide an encompassing solution to the increasing size
and complexity of the defects, and the variability of clinical situations.6, 7, 19-23 Free grafting
remains as a viable alternative, however, as previously mentioned vascularized tissue alternatives
seem superior alternatives. Various extranasal pedicled flaps can also be used for the
reconstruction of large defects of the anterior skull base, such as the transfrontal pericranial
flap19, 20, the transpterygoid temporoparietal fascia flap7, the palatal flap21, the facial artery
buccinator flap (FAB)22, and the occipital galeopericranial flap24. These offer reconstructive
alternatives in select patients, but they may be technically challenging and are associated to some
donor site morbidity. Furthermore, in some patients, these flaps may not be available due to
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compromise of their pedicle or donor site by tumor or prior surgery. A posterior pedicle inferior
turbinate flap has been previously described for reconstruction of clival and sellar defects.6, 25 In
contrast to the posterior pedicle inferior turbinate flap, the C-H flap incorporates the mucosa
anterior to the middle turbinate, extending beyond the lateral wall to the mucosa covering the
nasal bones, as well as the mucoperiosteum of the inferior nasal lateral wall, inferior meatus and
nasal floor. This results in a flap with a potential surface area that is three times the surface area
of that of the inferior turbinate flap, and a superior reach.
The ideal candidate for the C-H flap is a patient with a large surgical defect resulting
from a transplanum, transsellar, transclival or middle cranial fossa EEA, in whom the Hadad-
Bassagaisteguy nasoseptal flap is not available. Contraindications to the C-H flap include the
need to sacrifice its mucosal surface, pedicle or proximal blood supply to achieve oncologic
margins, and prior surgery or embolization of its main blood supply. . Prior high dose
radiotherapy or chemoradiotherapy should be taken into consideration; however, the lateral nasal
wall is not within the usual radiation fields of tumors originating or extending to the clivus, sella
or planum sphenoidale. In the rare instance where the flap has been irradiated we anticipate a
tolerance similar to the nasoseptal flap.
Harvesting of the C-H flap is not difficult assuming that the surgeon has experience with
endonasal endoscopic surgery. However, meticulous attention to its technical harvesting is
paramount for a favorable outcome. The absence of the posterior nasal septum greatly facilitates
the harvesting process, as it provides more working space. We expect that this scenario will not
be uncommon as the lack of nasal septum (compromised HBF donor site) is one of the
indications for C-H flap.
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Based on our early clinical experience with the C-H flap and our acquaintance with other
endonasal flaps, we expect minimal morbidity in the vast majority of the patients. Initial
morbidity is mostly associated to temporary, albeit significant, nasal crusting, which lasts until
re-mucosalization of the donor site is complete. It has been our observation that mucosalization
of the donor site progresses more rapidly than that of the nasoseptal flap. It does require,
however, nasal toilette and endoscopic debridement (every 1-2weeks for about 6 weeks). We
have not encountered problems with lacrimal outflow despite harvesting mucosa very close to
the opening of the nasolacrimal duct in the inferior meatus
CONCLUSION
Our anatomical cadaveric dissections and early clinical experience support the use of the
posterior pedicle lateral nasal wall and floor flap for vascularized reconstruction of large ventral
cranial base defects in select patients.
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REFERENCES:
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2. Kassam A, Carrau R, Snyderman C, Gardner P, Mintz A. Evolution of reconstructive
techniques following endoscopic expanded endonasal approaches. Neurosurg Focus, 2005. 19(1): p. E8.
3. Bhatki AM, Carrau RL, Snyderman CH, Prevedello DM, Gardner PA, Kassam AB. Endonasal Surgery of the Ventral Skull Base- Endoscopic Trans-cranial Surgery. OralMaxillofac Surg Clin North Am. 201 Feb; 22(1): 157-68.
4. Lund VJ, Stammberger H, Nicolai P, Castelnuovo P, Beham A, Bernal-Sprekelsen M,
Braun H, Cappabianca P, Carrau RL et al. European Position paper on endoscopic management of tumours of the nose paranasal sinuses and skull base. Rhinology. 2010 Jun 1; 48(2):1001-144.
5. Ong YK, Solares CA, Carrau RL, Snyderman CH. New Developments in transnasal
endoscopic surgery for malignancies of the sinonasal tract and adjacent skull base. Curr Opin Otolaryngol Head Neck Surg. 2010 Apr;18(2):107-13.
6. Fortes F, Carrau R, Snyderman C, Prevedello D, Vescan A, Mintz A, Gardner P, Kassam
A. The posterior pedicle inferior turbinate flap: a new vascularized flap for skull base reconstruction. Laryngoscope, 2007. 117(8): p. 1329-32.
7. Fortes F, Carrau R, Snyderman C, Kassam A, Prevedello D, Vescan A, Mintz A, Gardner
P. Transpterygoid transposition of a temporoparietal fascia flap: a new method for skull base reconstruction after endoscopic expanded endonasal approaches. Laryngoscope, 2007. 117(6): p. 970-6.
8. Hadad G, Bassagasteguy L, Carrau R, Mataza J, Kassam A, Snyderman C, Mintz A. A
novel reconstructive technique after endoscopic expanded endonasal approaches: vascular pedicle nasoseptal flap. Laryngoscope, 2006. 116(10): p. 1882-6.
9. Yoshioka N, Rhoton AL Jr., Vascular anatomy of the anteriorly based pericranial flap.
Neurosurgery. 2005 Jul;57(1 Suppl):11-6; discussion 11-6. 10. Zanation A, Carrau R, Snyderman C, Germanwala A, Gardner P, Prevedello D, Kassam A.
Nasoseptal flap reconstruction of high flow intraoperative cerebral spinal fluid leaks during endoscopic skull base surgery. Am J Rhinol Allergy. 2009; 23(5):518-21.
11. 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): p. 236-9
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12. Lee HY, Kim HU, Kim SS, Son EJ, Kim JW, Cho NH, Kim KS, Lee JG, Chung IH, Yoon
JH. Surgical anatomy of the sphenopalatine artery in lateral nasal wall. Laryngoscope, 2002. 112(10): p. 1813-8.
13. Hadar T, Ophir D, Yaniv E, Berger G. Inferior turbinate arterial supply: histologic
analysis and clinical implications. J Otolaryngol, 2005. 34(1): p. 46-50. 14. Padgham, N. and R. Vaughan-Jones, Cadaver studies of the anatomy of arterial supply to
the inferior turbinates. J R Soc Med, 1991. 84(12): p. 728-30. 15. Murakami, C.S., J.D. Kriet, and A.P. Ierokomos, Nasal reconstruction using the inferior
turbinate mucosal flap. Arch Facial Plast Surg, 1999. 1(2): p. 97-100. 16. Penna, V., H. Bannasch, and G.B. Stark, The turbinate flap for oronasal fistula closure.
Ann Plast Surg, 2007. 59(6): p. 679-81. 17. Friedman, M., H. Ibrahim, and V. Ramakrishnan, Inferior turbinate flap for repair of nasal
septal perforation. Laryngoscope, 2003. 113(8): p. 1425-8. 18. Sanan A, Abdel Aziz KM, Janjua RM, van Loveren HR, Keller JT. Colored silicone
injection for use in neurosurgical dissections: anatomic technical note. Neurosurgery, 1999. 45(5): p. 1267-71; discussion 1271-4.
19. Zanation AM, Snyderman CH, Carrau RL, Kassam AB, Gardner PA, Prevedello DM.
Minimally invasive endoscopic pericranial flap: a new method for endonasal skull base reconstruction. Laryngoscope, 2009. 119(1): p. 13-8.
20. Patel MR, Shah RN, Snyderman CH, Carrau RL, Germanwala AV, Kassam AB, Zanation
AM. Pericranial flap for endoscopic anterior skull-base reconstruction: clinical outcomes and radioanatomic analysis of preoperative planning. Neurosurgery. 2010 Mar; 66(3): 506-12.
21. Oliver C, Hackman T, Carrau R, Snyderman C, Kassam A, Prevedello D, Gardner P.
Palatal Flap Modifications Allow Pedicled Reconstruction of the Skull Base. Laryngoscope, 2008.
22. Rivera-Serrano CM, Oliver CL, Sok J, Prevedello DM, Gardner P, Snyderman CH,
Kassam AB, Carrau RL. Pedicled Facial Buccinator (FAB) Flap: A New Flap for Reconstruction of Skull Base Defects. Laryngoscope. 2010 Jul 7. [Epub ahead of print
23. Prevedello D, Barges-Coll J, Fernandez-Miranda J, Morera V, Jacobson D, Madhok R,
Zanation A, Snyderman C, Gardner P, Kassam A, Carrau R. Middle turbinate flap for skull base reconstruction: cadaveric feasibility study. Laryngoscope. 2009 Nov; 119(11): 2094-8
24. Rivera-Serrano CM, Oliver C, Prevedello D, Gardner P, Snyderman C, Kassam A, Carrau
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RL. Pedicled Facial Buccinator (FAB) flap: a new flap for reconstruction of skull base defects. Laryngoscope. 2010;120 Suppl 4:S23
25. Harvey RJ, Sheahan PO, Schlosser RJ. Inferior turbinate pedicle flap for endoscopic skull base defect repair. Am J Rhinol Allergy. 2009
FIGURES:
Figure 1. Incisions for the C-H flap.
Dashed lines represent the incisions. Ant-Sup incision (large black arrow) = Antero-superior
incision. Ant-Inf incision = Antero-inferior incision. IT = Inferior Turbinate. MT = Middle
turbinate. ST = Superior turbinate. Small curved black arrows = blood supply of the flap. White
arrow = Nasolacrimal duct opening. Dashed black (circles) line and small black arrow = an
incision can be made at the nasal floor to increase the arc of rotation of the flap. Please note that
the antero-inferior incision is directed laterally (from the head of the inferior turbinate) towards
the meatal side of the inferior turbinate / nasolacrimal duct opening (correlate with figure 2), in
order to incorporate the lateral-inferior nasal mucosal wall of the inferior meatus. The medial
aspect of the inferior turbinate is not incised.
Figure 2. Harvesting of the C-H flap from left side.
A. Incisions. Gray arrow = stump of middle turbinate. B. Incision (white arrow) at the head of
the inferior turbinate. C. Incision and elevation of the flap from the ascending process of the
maxilla (apm). F = flap. Nv = nasal vestibule. D. Dashed line = Extension of the incision across
the nasal floor. Small white arrow = Direction of the sagitally oriented incision along the floor of
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the nasal cavity, just lateral to the nasal septum (which extends posteriorly to a point that is at the
level of the sphenopalatine foramen in the coronal plane). E. Harvesting of the meatal aspect of
the inferior turbinate mucoperiosteum (black arrow). F. Elevation of the most anterior aspect of
the flap (dashed line represent incisions – correlate with figure 1 and 2a).
Figure 3. Harvesting of the C-H flap from left side.
A. Residual inferior turbinate bone is removed with Kerrison rongeurs. B. The mucosa of the
lateral aspect of the middle turbinate is elevated until it turns laterally towards the opening of the
nasolacrimal duct. Gray arrow = residual bone of inferior turbinate. White asterisk = mucosa
from the meatal side of the middle turbinate is reflected laterally. White arrow = approximate
location of the opening of the nasolacrimal duct in the middle meatus. C. Scissors are used to
cut the meatal mucosa towards the opening of the nasolacrimal duct. D. White arrow points the
nasolacrimal duct opening. Dashed line = incision line towards the nasal floor (just inferior to the
nasolacrimal duct opening). E. Incision is carried down towards the nasal floor / nasal septum
in the coronal plane. F. The the mucoperiosteum is elevated from the middle meatus and
reflected medially. White arrow = nasolacrimal duct opening.
Figure 4. Harvesting of the C-H flap from left side.
The nasal septum has been removed in this specimen. A. The mucoperiosteum is further elevated
posteriorly along the lateral nasal wall and the floor of the nasal cavity. Branches of the
sphenopalatine artery (black arrowhead) should be identified and preserved. B. Lateral (wall)
aspect of the flap completely elevated. White arrow = nasal choana. C. Nasal floor component
of the flap completely elevated. Dashed line represents the sagittally oriented incision along the
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floor of the nasal cavity (correlate with Figure 2D). D. Harvested flap. Black asterisk = nasal
floor component of the flap.
Figure 5. Transposition of the C-H flap.
A. Surgical defect. Gray arrow = clival defect. White arrow = residual nasal septum. Black
asterisk = Left inferior turbinate. White asterisk = Sphenoid sinus. B and C. The flap is
approximated to the defect. D. Flap completely covering the sphenoid sinus and clival
defect
Figure 6. Postoperative MRI.
Sagittal T1 weighted contrasted MRI demonstrating the vascularized C-H flap (arrows)
combined with a free abdominal fat graft (arrowheads) to reconstruct a clival defect.