ORIGINAL ARTICLE
The nasal floor pedicled flap: a novel technique for use in skull base reconstruction Pedram Daraei, BS1 , Nelson M. Oyesiku, MD, PhD, FACS2 and Zara M. Patel, MD3
Background: Skull base reconstruction can be accomplished using various donor sites. Vascularized tissue, commonly the nasoseptal flap, is the most effective option for large defects or high flow leaks. In cases where the septum cannot be used, a mucoperiosteal flap from the nasal floor, pedicled from the sphenopalatine artery, is a viable option without reported outcomes. The aim of this work was to describe this flap and to report successful outcomes in a cohort of patients. Methods: Retrospective chart review of patients seen by the senior author from 2011 to 2013 requiring skull base reconstruction for defects with cerebrospinal fluid leak. Results: A total of 108 patients underwent endoscopic skull base reconstruction. Ten patients had reconstruction with use of a pedicled nasal floor flap. Mean age was 53.3 years. Defects involved the ethmoid roof in 5 patients, sellar floor in 2, clivus in 2, and planum sphenoidale in 1. Reasons why the septal flap could not be used were intentional sacrifice due to disease involvement, sacrifice for proper exposure, or previous septal perforation. Mean length of follow-
O
ver the last decade, endoscopic approaches to the skull base have increased exponentially, exposing areas previously very difficult to access. Increased endoscopic experience, along with the development of better endoscopic instrumentation, has lead to increased maneuverability, giving the surgeon the ability to precisely harvest intranasal tissue for reconstruction of the ante-
1 Emory University School of Medicine, Atlanta, GA; 2 Department of Neurosurgery, Emory University, Atlanta, GA; 3 Department of Otolaryngology–Head and Neck Surgery, Emory University, Atlanta, GA
Correspondence to: Zara M. Patel, MD, Department of Otolaryngology– Head and Neck Surgery, 550 Peachtree St. NE, Medical Office Tower, 11th Floor, Atlanta, GA 30308; e-mail: [email protected] Potential conflict of interest: None provided. Presented orally at the Spring Meeting of the American Rhinological Society (ARS) at the Combined Otolaryngological Spring Meetings (COSM) on May 17, 2014, Las Vegas, NV. Received: 14 April 2014; Revised: 27 May 2014; Accepted: 10 June 2014 DOI: 10.1002/alr.21369 View this article online at wileyonlinelibrary.com.
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up was 10.2 (range, 4 to 25) months. No patient developed cerebrospinal fluid leaks postoperatively. Conclusion: Nasal floor pedicled flaps are an effective alternative to nasoseptal flaps for reconstruction of the skull base, and have not been previously described in the literature. Outcomes are promising in our small cohort of patients. If the septum must be sacrificed, aention should be paid to the nasal floor, which provides a large mucoperiosteal flap that can be consistently exposed and elevated C 2014 ARS-AAOA, LLC. by the experienced surgeon.
Key Words: skull base reconstruction; nasal reconstruction; reconstructive techniques; cerebrospinal fluid leak; nasal floor; vascularized flap; pedicled flap How to Cite this Article: Daraei P, Oyesiku NM, Patel ZM. The nasal floor pedicled flap: a novel technique for use in skull base reconstruction. Int Forum Allergy Rhinol. 2014;4:937–943.
rior skull base. The nasoseptal flap, also known as the Hadad-Bassagasteguy flap, based off of the posterior septal branches of the sphenopalatine artery, has become the workhorse of reconstruction in skull base reconstruction due to its robust, consistent blood supply as well as its strength, length, and pliability.1 Use of this flap has decreased rates of recurrent cerebrospinal fluid (CSF) leak after reconstruction to under 5%.1, 2 Unfortunately, either due to involvement by tumor pathology or other reasons such as prior septal perforation, the nasoseptal flap is not always available for use. Other methods exist for the reconstruction of skull base defects, including the use of synthetic materials, free grafts, and vascularized flaps. Some of the documented vascularized flaps include pericranial flaps, tunneled temporoparietal flaps, inferior turbinate flaps, middle turbinate flaps, anterior lateral nasal wall flaps, palatal flaps, occipital flaps, and buccinators flaps, among others.3 The nasal floor surface is covered by a large, flat, mucoperiosteal layer, which, although thinner than the typical nasoseptal flap, has otherwise similar qualities of length
Daraei et al.
FIGURE 1. Sketch of nasal floor flap blood supply.
FIGURE 2. Large septal perforation.
and pliability. The nasal floor free graft for use in reconstruction of the skull base has been described in a cadaveric model as well as in 2 patients.3 Rotational nasal floor flaps have long been described in rhinology and facial plastics literature for reconstruction of the nasal cavity itself,4–6 as well as for maxillectomy defects.5 However, a pedicled nasal floor flap for use in the reconstruction of the skull base has not been documented in the literature. The nasal floor flap relies on the integrity of the posteroinferior aspect of the nasal septum, and if this region is uninvolved with disease, the nasal floor can also be harvested as a vascularized flap, pedicled off the septal branches of the sphenopalatine artery as they come across the sphenoid rostrum. The nasal floor receives blood supply from the anastomoses between the sphenopalatine, the greater palatine, and the descending palatine and the superior labial arteries.7–9 It is likely due to this rich anastomotic network that it can remain healthy and vascularized when isolated to just 1 supply source. In cases where skull base reconstruc-
tion is necessary, and the nasal septum cannot be harvested, the nasal floor flap can serve as a similar, vascularized alternative. The aim of this study is to describe the nasal floor flap in the reconstruction of skull base defects and to report the experience and outcomes using this flap in a cohort of patients at this institution.
Patients and methods A retrospective chart-review study design was employed. Patients who were seen in the Rhinology division at Emory University from October 2011 to July 2013 for CSF leaks or any skull base tumor whose resection would cause an intraoperative CSF leak, and who subsequently underwent skull base reconstruction by the senior author (Z.M.P.), were included. The charts were then reviewed for type of skull base reconstruction, and patients who had reconstruction with anything other than a pedicled nasal floor flap were excluded. For each patient we recorded age and gender,
International Forum of Allergy & Rhinology, Vol. 4, No. 11, November 2014
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Nasal floor pedicled flap for skull base reconstruction
FIGURE 3. Extruded foreign material (polymethylmethacrylate) from prior pituitary surgery at an outside hospital, extending from sella into sphenoid sinus.
FIGURE 4. Demarcating superior border of pedicle.
diagnosis, reason why the septum was not useable, anatomic region of defect, whether or not there was a postoperative CSF leak, length of follow-up, and all adverse events. The Institutional Review Board at Emory University School of Medicine approved this study.
Surgical technique Intraoperatively, at times the primary pathology was addressed first, leaving behind a skull base defect requiring reconstruction, and other times the flap was raised first if we knew we would need it at the end of the resection. If the commonly used nasoseptal flap could not be used, and the use of a free graft was not optimal based on either size of the defect or high flow of CSF, attention was then focused onto the nasal floor flap (Figs. 1 to 3). A Colorado tip Bovie is used to delineate the pedicle from the lateral nasal wall inferiorly at the level of the choana and superiorly just below the sphenoid ostium, after the location of the
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sphenoid os is noted and opened with a Freer (Fig. 4). The lower incision is extended inferiorly to delineate the posterior border of the nasal floor flap just anterior to the junction between the hard and soft palate (Fig. 5). The upper incision is then taken along the medial floor, including whatever small amount of septal mucosa that may be left for use, and brought all the way anteriorly, just behind the mucocutaneous junction of the nasal skin (Fig. 6). An anterior border is then created just posterior to the mucocutaneous junction of the nasal skin. For the lateral border, an incision is made along the lateral-most aspect of the nasal floor, and can be taken along the lateral wall up to Hasner’s valve without disrupting the outflow of the nasolacrimal duct. This is continued posteriorly to meet the posterior incision of the flap (Fig. 7). The flap is then elevated using a Cottle elevator, and a suction Freer (Figs. 8A and B). At this point, if the case is just beginning, the flap can be tucked away in the nasopharynx for safekeeping while the surgeon addresses other pathology
Daraei et al.
FIGURE 5. Demarcating posterior border of flap, just anterior to the hard and soft palate junction.
FIGURE 6. Medial border including small amount of remnant septum.
FIGURE 7. Lateral border, seen here beneath the inferior turbinate, but can be brought up along the lateral nasal wall as well.
within the nasal cavity, sinuses, or skull base. If the defect is in the clivus, the maxillary sinus can be opened to store the flap while operating in the nasopharynx. Subsequently, the nasal floor flap can be retrieved and rotated on its
pedicle to reconstruct a given defect (Figs. 9A and B). We then use fibrin sealant overlying the flap to help keep it in position along with thrombin-soaked Gelfoam. Nasopore is then also placed to help bolster the flap in position.
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Nasal floor pedicled flap for skull base reconstruction
FIGURE 8. (A) Cottle elevation of flap at anterior border. (B) Continuing elevation with the Cottle at the posterior nasal floor.
FIGURE 9. (A) Close up view of flap unfurled over sellar defect. (B) Flap rotated into sphenoid to cover sellar defect.
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Daraei et al.
Results From October 2011 to July 2013, 108 patients underwent endoscopic skull base reconstruction. Ten patients had reconstruction with use of a pedicled nasal floor flap: 6 male and 4 female. Mean age at the time of intervention was 53.3 years, ranging from 35 to 77 years. Of the 10 patients, 2 had inverted papilloma involving dura, 2 had squamous cell carcinoma (SCC), 2 had pituitary adenomas, and 1 each with meningioma, melanoma, adenoid cystic carcinoma, and craniopharyngioma. Defects created by the disease involved the ethmoid roof in 5 patients, sellar floor in 2, clivus in 2, and planum sphenoidale in 1. The mean length of follow-up was 10.2 (range, 4 to 25) months. In each of the 10 patients, the septal flap could not be used for the following reasons: 5 patients required intentional sacrifice of the nasal septum due to disease involvement, 3 patients had a large septal perforation from a previous resection, 1 with a septal perforation due to cocaine abuse, and 1 required septal sacrifice for proper exposure. Of the 10 patients who underwent reconstruction of the skull base with the pedicled nasal floor flap, none experienced intraoperative adverse events. Postoperatively, none of the 10 patients developed cerebrospinal fluid leaks or intracranial adverse events (Table 1). No patient suffered complications of anesthesia. One patient had a myocardial infarction postoperatively without
sequelae on follow-up. Another patient developed diabetes insipidus postoperatively that resolved within 2 months. One patient developed expected right vision loss after external beam radiation therapy for local disease control.
Discussion Traditionally, the nasoseptal flap has been used for reconstruction of high-flow CSF leaks or large dural defects located at the anterior and middle skull base. Multiple studies have shown the reliability and effectiveness of the nasoseptal flap in repairing CSF leaks, making it the most commonly used method for reconstruction of the skull base. However, in cases where the septum cannot be used, the nasal floor provides a large, pliable mucosal flap, similar in quality to the nasoseptal flap. Tissue flaps from the nasal floor have been previously used in the reconstruction of septal perforations.10–12 However, to date, our study detailing the use of the nasal floor flap for skull base reconstruction is the first of its kind. The flap relies on arterial supply downstream of the sphenopalatine pedicle. The borders of the nasal floor flap include the mucocutaneous border of the nasal cavity anteriorly, the posterior edge of the hard palate posteriorly, the lateral nasal wall just inferior to the opening of the nasolacrimal duct laterally, and the confluence of the nasal septum and the nasal floor medially. If necessary, the flap
TABLE 1. Patient characteristics and outcomes Patient Age (years) Gender
Diagnosis
Reason why the septum was not useable
Location of skull base defect
Postoperative Intracranial CSF leak (Y/N) adverse
Other adverse events
events
Length of follow-up (months)
1
45
M
Inverted papilloma
Majority involved in tumor
Ethmoid roof
N
None
None
25
2
62
M
Inverted papilloma
Majority involved in tumor
Ethmoid roof
N
None
MI, no sequelae
14
3
56
M
SCC
Majority involved in tumor
Ethmoid roof
N
None
None
6
4
77
F
SCC
Majority involved in tumor
Ethmoid roof
N
None
None
4
5
35
M
Meningioma
Large portion of septum resected on prior approach at OSH
Planum sphenoidale
N
None
None
12
6
50
F
Pituitary adenoma
Large septal perforation from prior pituitary tumor resection at OSH
Sellar floor
N
None
None
6
7
63
F
Pituitary adenoma
Large septal perforation from prior pituitary tumor resection at OSH
Sellar floor
N
None
DI, resolved within 2 months
6
8
54
M
Melanoma
Majority involved in tumor
Ethmoid roof
N
None
Right visual loss after RT
8
9
52
M
Adenoid cystic carcinoma
Large septal perforation from prior cocaine use
Clivus
N
None
None
6
10
39
F
Craniopharyngioma
Septum taken for exposure during resection of tumor
Clivus
N
None
None
15
CSF = cerebrospinal fluid; DI = diabetes insipidus; MI = myocardial infarction; OSH = outside hospital; RT = radiation therapy; SCC = squamous cell carcinoma.
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can be extended laterally to include a portion of the inferior turbinate. However, care must be taken to avoid damage to the nasolacrimal duct that nests in the inferior meatus. Once exposed and elevated, the nasal floor flap can be rotated on its pedicle, which lies superomedially, to be placed on the skull base defect. Postoperatively, patients are asked to spray nasal saline mist for the first 2 weeks and thereafter to irrigate regularly with saline solution. Follow-up visits should include evaluation for recurrence of disease, resolution of CSF rhinorrhea, proper healing of the skull base defect, and remucosalization of the nasal floor flap site. Remucosalization, in this limited experience, actually occurs faster at the nasal floor than along the nasal septum, and most patients are completely healed at the harvest site 1 month out from surgery. In this study, 100% of patients who underwent skull base reconstruction using the nasal floor flap had resolution of CSF leaks postoperatively at a mean follow-up of 10.2 (range, 4 to 25) months. These results are comparable to the established results seen with the use of the nasoseptal flap. A limitation of this study includes the number of patients in this cohort. This is simply an initial report on a cohort of patients undergoing skull base reconstruction using the nasal floor flap, and given the fact that this technique is novel and only used when more established
options are unavailable or not optimal, small numbers were expected.
Conclusion The pedicled nasal floor flap is a useful and effective alternative to the nasoseptal flap for skull base reconstruction when the nasoseptal flap is unavailable. Based off of the sphenopalatine artery, the nasal floor flap gives the surgeon a reliable mucoperiosteal vascularized flap that is sustainable and can conform to almost anywhere along the anterior and middle skull base to repair cerebrospinal fluid leaks and dural defects. This study demonstrated that the flap is effective in repairing CSF leaks in 100% of our patients at a mean follow-up of 10.2 months. These results are comparable to long-term results seen when the nasoseptal flap is used to repair CSF leaks, giving the skull base surgeon an increased repertoire of vascularized flaps for repair of CSF leaks and the ability to improve outcomes in skull base reconstruction.
Acknowledgment The senior author (Z.M.P.) acknowledges Dr. Peter H. Hwang, who originally demonstrated to her the harvesting of the nasal floor mucosa as a free graft, which was the basis for developing the nasal floor pedicled flap.
References 1.
2.
3.
4.
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Hadad G, Bassagasteguy L, Carrau RL, et al. A novel reconstructive technique after endoscopic expanded endonasal approaches: vascular pedicle nasoseptal flap. Laryngoscope. 2006;116:1882–1886. Kassam AB, Thomas A, Carrau RL, et al. Endoscopic reconstruction of the cranial base using a pedicled nasoseptal flap. Neurosurgery. 2008;63(1 Suppl 1): ONS44-ONS52. Patel MR, Taylor RJ, Hackman TG, et al. Beyond the nasoseptal flap: outcomes and pearls with secondary flaps in endoscopic endonasal skull base reconstruction. Laryngoscope. 2014;124:846–852. Karlan MS, Ossof RH, Sisson GA. A compendium of intranasal flaps. Laryngoscope. 1982;92:774–782.
5.
6.
7.
8.
Rotenberg B, Sowerby L. The floor-of-nose flap for reconstruction of endoscopic maxillectomy defects. Laryngoscope. 2010;120:1795– 1797. Presutti L, Ciufelli MA, Marchioni D, Villari D, Marchetti A, Mattioli F. Nasal septal perforations: our surgical technique. Otolaryngol Head Neck Surg. 2007;136:369–372. Stucker FJ, de Souza C, Kenyon GS, Lian TS, Draf W, Schick B, eds. Rhinology and Facial Plastic Surgery. Berlin: Springer; 2009. Stewart M, Selesnick S. Differential Diagnosis in Otolaryngology: Head and Neck Surgery. New York: Thieme; 2010.
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9.
Hansen JT. Netter’s Clinical Anatomy. 2nd ed. Philadelphia, PA: Saunders-Elsevier; 2010. 10. Suh, JD, Ramakrishnan VR, DeConde AS. Nasal floor free mucosal graft for skull base reconstruction and cerebrospinal fluid leak repair. Ann Otol Rhinol Laryngol. 2012;121:91–95. 11. Teymoortash A, Hoch S, Eivazi B, Werner JA. Experiences with a new surgical technique for closure of large perforations of the nasal septum in 55 patients. Am J Rhinol Allergy. 2011;25:193–197. 12. Teymoortash A, Werner JA. Repair of nasal septal perforation using a simple unilateral inferior meatal mucosal flap. J Plast Reconstr Aesthet Surg. 2009;62:1261-1264.
The nasal floor pedicled flap: a novel technique for use in skull base reconstruction Pedram Daraei, BS1 , Nelson M. Oyesiku, MD, PhD, FACS2 and Zara M. Patel, MD3
Background: Skull base reconstruction can be accomplished using various donor sites. Vascularized tissue, commonly the nasoseptal flap, is the most effective option for large defects or high flow leaks. In cases where the septum cannot be used, a mucoperiosteal flap from the nasal floor, pedicled from the sphenopalatine artery, is a viable option without reported outcomes. The aim of this work was to describe this flap and to report successful outcomes in a cohort of patients. Methods: Retrospective chart review of patients seen by the senior author from 2011 to 2013 requiring skull base reconstruction for defects with cerebrospinal fluid leak. Results: A total of 108 patients underwent endoscopic skull base reconstruction. Ten patients had reconstruction with use of a pedicled nasal floor flap. Mean age was 53.3 years. Defects involved the ethmoid roof in 5 patients, sellar floor in 2, clivus in 2, and planum sphenoidale in 1. Reasons why the septal flap could not be used were intentional sacrifice due to disease involvement, sacrifice for proper exposure, or previous septal perforation. Mean length of follow-
O
ver the last decade, endoscopic approaches to the skull base have increased exponentially, exposing areas previously very difficult to access. Increased endoscopic experience, along with the development of better endoscopic instrumentation, has lead to increased maneuverability, giving the surgeon the ability to precisely harvest intranasal tissue for reconstruction of the ante-
1 Emory University School of Medicine, Atlanta, GA; 2 Department of Neurosurgery, Emory University, Atlanta, GA; 3 Department of Otolaryngology–Head and Neck Surgery, Emory University, Atlanta, GA
Correspondence to: Zara M. Patel, MD, Department of Otolaryngology– Head and Neck Surgery, 550 Peachtree St. NE, Medical Office Tower, 11th Floor, Atlanta, GA 30308; e-mail: [email protected] Potential conflict of interest: None provided. Presented orally at the Spring Meeting of the American Rhinological Society (ARS) at the Combined Otolaryngological Spring Meetings (COSM) on May 17, 2014, Las Vegas, NV. Received: 14 April 2014; Revised: 27 May 2014; Accepted: 10 June 2014 DOI: 10.1002/alr.21369 View this article online at wileyonlinelibrary.com.
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up was 10.2 (range, 4 to 25) months. No patient developed cerebrospinal fluid leaks postoperatively. Conclusion: Nasal floor pedicled flaps are an effective alternative to nasoseptal flaps for reconstruction of the skull base, and have not been previously described in the literature. Outcomes are promising in our small cohort of patients. If the septum must be sacrificed, aention should be paid to the nasal floor, which provides a large mucoperiosteal flap that can be consistently exposed and elevated C 2014 ARS-AAOA, LLC. by the experienced surgeon.
Key Words: skull base reconstruction; nasal reconstruction; reconstructive techniques; cerebrospinal fluid leak; nasal floor; vascularized flap; pedicled flap How to Cite this Article: Daraei P, Oyesiku NM, Patel ZM. The nasal floor pedicled flap: a novel technique for use in skull base reconstruction. Int Forum Allergy Rhinol. 2014;4:937–943.
rior skull base. The nasoseptal flap, also known as the Hadad-Bassagasteguy flap, based off of the posterior septal branches of the sphenopalatine artery, has become the workhorse of reconstruction in skull base reconstruction due to its robust, consistent blood supply as well as its strength, length, and pliability.1 Use of this flap has decreased rates of recurrent cerebrospinal fluid (CSF) leak after reconstruction to under 5%.1, 2 Unfortunately, either due to involvement by tumor pathology or other reasons such as prior septal perforation, the nasoseptal flap is not always available for use. Other methods exist for the reconstruction of skull base defects, including the use of synthetic materials, free grafts, and vascularized flaps. Some of the documented vascularized flaps include pericranial flaps, tunneled temporoparietal flaps, inferior turbinate flaps, middle turbinate flaps, anterior lateral nasal wall flaps, palatal flaps, occipital flaps, and buccinators flaps, among others.3 The nasal floor surface is covered by a large, flat, mucoperiosteal layer, which, although thinner than the typical nasoseptal flap, has otherwise similar qualities of length
Daraei et al.
FIGURE 1. Sketch of nasal floor flap blood supply.
FIGURE 2. Large septal perforation.
and pliability. The nasal floor free graft for use in reconstruction of the skull base has been described in a cadaveric model as well as in 2 patients.3 Rotational nasal floor flaps have long been described in rhinology and facial plastics literature for reconstruction of the nasal cavity itself,4–6 as well as for maxillectomy defects.5 However, a pedicled nasal floor flap for use in the reconstruction of the skull base has not been documented in the literature. The nasal floor flap relies on the integrity of the posteroinferior aspect of the nasal septum, and if this region is uninvolved with disease, the nasal floor can also be harvested as a vascularized flap, pedicled off the septal branches of the sphenopalatine artery as they come across the sphenoid rostrum. The nasal floor receives blood supply from the anastomoses between the sphenopalatine, the greater palatine, and the descending palatine and the superior labial arteries.7–9 It is likely due to this rich anastomotic network that it can remain healthy and vascularized when isolated to just 1 supply source. In cases where skull base reconstruc-
tion is necessary, and the nasal septum cannot be harvested, the nasal floor flap can serve as a similar, vascularized alternative. The aim of this study is to describe the nasal floor flap in the reconstruction of skull base defects and to report the experience and outcomes using this flap in a cohort of patients at this institution.
Patients and methods A retrospective chart-review study design was employed. Patients who were seen in the Rhinology division at Emory University from October 2011 to July 2013 for CSF leaks or any skull base tumor whose resection would cause an intraoperative CSF leak, and who subsequently underwent skull base reconstruction by the senior author (Z.M.P.), were included. The charts were then reviewed for type of skull base reconstruction, and patients who had reconstruction with anything other than a pedicled nasal floor flap were excluded. For each patient we recorded age and gender,
International Forum of Allergy & Rhinology, Vol. 4, No. 11, November 2014
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Nasal floor pedicled flap for skull base reconstruction
FIGURE 3. Extruded foreign material (polymethylmethacrylate) from prior pituitary surgery at an outside hospital, extending from sella into sphenoid sinus.
FIGURE 4. Demarcating superior border of pedicle.
diagnosis, reason why the septum was not useable, anatomic region of defect, whether or not there was a postoperative CSF leak, length of follow-up, and all adverse events. The Institutional Review Board at Emory University School of Medicine approved this study.
Surgical technique Intraoperatively, at times the primary pathology was addressed first, leaving behind a skull base defect requiring reconstruction, and other times the flap was raised first if we knew we would need it at the end of the resection. If the commonly used nasoseptal flap could not be used, and the use of a free graft was not optimal based on either size of the defect or high flow of CSF, attention was then focused onto the nasal floor flap (Figs. 1 to 3). A Colorado tip Bovie is used to delineate the pedicle from the lateral nasal wall inferiorly at the level of the choana and superiorly just below the sphenoid ostium, after the location of the
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sphenoid os is noted and opened with a Freer (Fig. 4). The lower incision is extended inferiorly to delineate the posterior border of the nasal floor flap just anterior to the junction between the hard and soft palate (Fig. 5). The upper incision is then taken along the medial floor, including whatever small amount of septal mucosa that may be left for use, and brought all the way anteriorly, just behind the mucocutaneous junction of the nasal skin (Fig. 6). An anterior border is then created just posterior to the mucocutaneous junction of the nasal skin. For the lateral border, an incision is made along the lateral-most aspect of the nasal floor, and can be taken along the lateral wall up to Hasner’s valve without disrupting the outflow of the nasolacrimal duct. This is continued posteriorly to meet the posterior incision of the flap (Fig. 7). The flap is then elevated using a Cottle elevator, and a suction Freer (Figs. 8A and B). At this point, if the case is just beginning, the flap can be tucked away in the nasopharynx for safekeeping while the surgeon addresses other pathology
Daraei et al.
FIGURE 5. Demarcating posterior border of flap, just anterior to the hard and soft palate junction.
FIGURE 6. Medial border including small amount of remnant septum.
FIGURE 7. Lateral border, seen here beneath the inferior turbinate, but can be brought up along the lateral nasal wall as well.
within the nasal cavity, sinuses, or skull base. If the defect is in the clivus, the maxillary sinus can be opened to store the flap while operating in the nasopharynx. Subsequently, the nasal floor flap can be retrieved and rotated on its
pedicle to reconstruct a given defect (Figs. 9A and B). We then use fibrin sealant overlying the flap to help keep it in position along with thrombin-soaked Gelfoam. Nasopore is then also placed to help bolster the flap in position.
International Forum of Allergy & Rhinology, Vol. 4, No. 11, November 2014
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Nasal floor pedicled flap for skull base reconstruction
FIGURE 8. (A) Cottle elevation of flap at anterior border. (B) Continuing elevation with the Cottle at the posterior nasal floor.
FIGURE 9. (A) Close up view of flap unfurled over sellar defect. (B) Flap rotated into sphenoid to cover sellar defect.
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Daraei et al.
Results From October 2011 to July 2013, 108 patients underwent endoscopic skull base reconstruction. Ten patients had reconstruction with use of a pedicled nasal floor flap: 6 male and 4 female. Mean age at the time of intervention was 53.3 years, ranging from 35 to 77 years. Of the 10 patients, 2 had inverted papilloma involving dura, 2 had squamous cell carcinoma (SCC), 2 had pituitary adenomas, and 1 each with meningioma, melanoma, adenoid cystic carcinoma, and craniopharyngioma. Defects created by the disease involved the ethmoid roof in 5 patients, sellar floor in 2, clivus in 2, and planum sphenoidale in 1. The mean length of follow-up was 10.2 (range, 4 to 25) months. In each of the 10 patients, the septal flap could not be used for the following reasons: 5 patients required intentional sacrifice of the nasal septum due to disease involvement, 3 patients had a large septal perforation from a previous resection, 1 with a septal perforation due to cocaine abuse, and 1 required septal sacrifice for proper exposure. Of the 10 patients who underwent reconstruction of the skull base with the pedicled nasal floor flap, none experienced intraoperative adverse events. Postoperatively, none of the 10 patients developed cerebrospinal fluid leaks or intracranial adverse events (Table 1). No patient suffered complications of anesthesia. One patient had a myocardial infarction postoperatively without
sequelae on follow-up. Another patient developed diabetes insipidus postoperatively that resolved within 2 months. One patient developed expected right vision loss after external beam radiation therapy for local disease control.
Discussion Traditionally, the nasoseptal flap has been used for reconstruction of high-flow CSF leaks or large dural defects located at the anterior and middle skull base. Multiple studies have shown the reliability and effectiveness of the nasoseptal flap in repairing CSF leaks, making it the most commonly used method for reconstruction of the skull base. However, in cases where the septum cannot be used, the nasal floor provides a large, pliable mucosal flap, similar in quality to the nasoseptal flap. Tissue flaps from the nasal floor have been previously used in the reconstruction of septal perforations.10–12 However, to date, our study detailing the use of the nasal floor flap for skull base reconstruction is the first of its kind. The flap relies on arterial supply downstream of the sphenopalatine pedicle. The borders of the nasal floor flap include the mucocutaneous border of the nasal cavity anteriorly, the posterior edge of the hard palate posteriorly, the lateral nasal wall just inferior to the opening of the nasolacrimal duct laterally, and the confluence of the nasal septum and the nasal floor medially. If necessary, the flap
TABLE 1. Patient characteristics and outcomes Patient Age (years) Gender
Diagnosis
Reason why the septum was not useable
Location of skull base defect
Postoperative Intracranial CSF leak (Y/N) adverse
Other adverse events
events
Length of follow-up (months)
1
45
M
Inverted papilloma
Majority involved in tumor
Ethmoid roof
N
None
None
25
2
62
M
Inverted papilloma
Majority involved in tumor
Ethmoid roof
N
None
MI, no sequelae
14
3
56
M
SCC
Majority involved in tumor
Ethmoid roof
N
None
None
6
4
77
F
SCC
Majority involved in tumor
Ethmoid roof
N
None
None
4
5
35
M
Meningioma
Large portion of septum resected on prior approach at OSH
Planum sphenoidale
N
None
None
12
6
50
F
Pituitary adenoma
Large septal perforation from prior pituitary tumor resection at OSH
Sellar floor
N
None
None
6
7
63
F
Pituitary adenoma
Large septal perforation from prior pituitary tumor resection at OSH
Sellar floor
N
None
DI, resolved within 2 months
6
8
54
M
Melanoma
Majority involved in tumor
Ethmoid roof
N
None
Right visual loss after RT
8
9
52
M
Adenoid cystic carcinoma
Large septal perforation from prior cocaine use
Clivus
N
None
None
6
10
39
F
Craniopharyngioma
Septum taken for exposure during resection of tumor
Clivus
N
None
None
15
CSF = cerebrospinal fluid; DI = diabetes insipidus; MI = myocardial infarction; OSH = outside hospital; RT = radiation therapy; SCC = squamous cell carcinoma.
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Nasal floor pedicled flap for skull base reconstruction
can be extended laterally to include a portion of the inferior turbinate. However, care must be taken to avoid damage to the nasolacrimal duct that nests in the inferior meatus. Once exposed and elevated, the nasal floor flap can be rotated on its pedicle, which lies superomedially, to be placed on the skull base defect. Postoperatively, patients are asked to spray nasal saline mist for the first 2 weeks and thereafter to irrigate regularly with saline solution. Follow-up visits should include evaluation for recurrence of disease, resolution of CSF rhinorrhea, proper healing of the skull base defect, and remucosalization of the nasal floor flap site. Remucosalization, in this limited experience, actually occurs faster at the nasal floor than along the nasal septum, and most patients are completely healed at the harvest site 1 month out from surgery. In this study, 100% of patients who underwent skull base reconstruction using the nasal floor flap had resolution of CSF leaks postoperatively at a mean follow-up of 10.2 (range, 4 to 25) months. These results are comparable to the established results seen with the use of the nasoseptal flap. A limitation of this study includes the number of patients in this cohort. This is simply an initial report on a cohort of patients undergoing skull base reconstruction using the nasal floor flap, and given the fact that this technique is novel and only used when more established
options are unavailable or not optimal, small numbers were expected.
Conclusion The pedicled nasal floor flap is a useful and effective alternative to the nasoseptal flap for skull base reconstruction when the nasoseptal flap is unavailable. Based off of the sphenopalatine artery, the nasal floor flap gives the surgeon a reliable mucoperiosteal vascularized flap that is sustainable and can conform to almost anywhere along the anterior and middle skull base to repair cerebrospinal fluid leaks and dural defects. This study demonstrated that the flap is effective in repairing CSF leaks in 100% of our patients at a mean follow-up of 10.2 months. These results are comparable to long-term results seen when the nasoseptal flap is used to repair CSF leaks, giving the skull base surgeon an increased repertoire of vascularized flaps for repair of CSF leaks and the ability to improve outcomes in skull base reconstruction.
Acknowledgment The senior author (Z.M.P.) acknowledges Dr. Peter H. Hwang, who originally demonstrated to her the harvesting of the nasal floor mucosa as a free graft, which was the basis for developing the nasal floor pedicled flap.
References 1.
2.
3.
4.
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Hadad G, Bassagasteguy L, Carrau RL, et al. A novel reconstructive technique after endoscopic expanded endonasal approaches: vascular pedicle nasoseptal flap. Laryngoscope. 2006;116:1882–1886. Kassam AB, Thomas A, Carrau RL, et al. Endoscopic reconstruction of the cranial base using a pedicled nasoseptal flap. Neurosurgery. 2008;63(1 Suppl 1): ONS44-ONS52. Patel MR, Taylor RJ, Hackman TG, et al. Beyond the nasoseptal flap: outcomes and pearls with secondary flaps in endoscopic endonasal skull base reconstruction. Laryngoscope. 2014;124:846–852. Karlan MS, Ossof RH, Sisson GA. A compendium of intranasal flaps. Laryngoscope. 1982;92:774–782.
5.
6.
7.
8.
Rotenberg B, Sowerby L. The floor-of-nose flap for reconstruction of endoscopic maxillectomy defects. Laryngoscope. 2010;120:1795– 1797. Presutti L, Ciufelli MA, Marchioni D, Villari D, Marchetti A, Mattioli F. Nasal septal perforations: our surgical technique. Otolaryngol Head Neck Surg. 2007;136:369–372. Stucker FJ, de Souza C, Kenyon GS, Lian TS, Draf W, Schick B, eds. Rhinology and Facial Plastic Surgery. Berlin: Springer; 2009. Stewart M, Selesnick S. Differential Diagnosis in Otolaryngology: Head and Neck Surgery. New York: Thieme; 2010.
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9.
Hansen JT. Netter’s Clinical Anatomy. 2nd ed. Philadelphia, PA: Saunders-Elsevier; 2010. 10. Suh, JD, Ramakrishnan VR, DeConde AS. Nasal floor free mucosal graft for skull base reconstruction and cerebrospinal fluid leak repair. Ann Otol Rhinol Laryngol. 2012;121:91–95. 11. Teymoortash A, Hoch S, Eivazi B, Werner JA. Experiences with a new surgical technique for closure of large perforations of the nasal septum in 55 patients. Am J Rhinol Allergy. 2011;25:193–197. 12. Teymoortash A, Werner JA. Repair of nasal septal perforation using a simple unilateral inferior meatal mucosal flap. J Plast Reconstr Aesthet Surg. 2009;62:1261-1264.
