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cta Otorrinolaringol Esp. 2014;65(4):242---248

www.elsevier.es/otorrino

RIGINAL ARTICLE

edicle Flaps Based on the Sphenopalatine Artery:natomical and Surgical Study�

uan R. Gras-Cabrerizo,a,∗ Juan R. Gras-Albert,b Irene Monjas-Canovas,b

lena García-Garrigós,c Joan R. Montserrat-Gili,a Francisco Sánchez del Campo,d

atarzyna Kolanczak,a Humbert Massegur-Solencha

Servicio de Otorrinolaringología, Hospital de la Santa Creu i Sant Pau, Universidad Autónoma de Barcelona, Barcelona, SpainServicio de Otorrinolaringología, Hospital General Universitario, Universidad Miguel Hernández, Alicante, SpainServicio de Radiología, Hospital General Universitario, Universidad Miguel Hernández, Alicante, SpainUnidad de Anatomía y Embriología Humana, Universidad Miguel Hernández, Alicante, Spain

eceived 13 December 2013; accepted 1 February 2014

KEYWORDSPedicle flaps;Sphenopalatineartery;Skull base;Endoscopic surgery

AbstractIntroduction: Local pedicle flaps based on the sphenopalatine artery make it possible to recon-struct large defects of the skull base (SB).Material and methods: From January 2008 to January 2013, 64 lesions with involvement of SBwere analysed. These lesions were treated using endoscopic endonasal approach and requireda pedicle flap based on the sphenopalatine artery. In addition, measurements and flexibility ofthe flaps were examined in 4 cadaveric nasal cavities.Results: Surgical group. Sixty-four nasoseptal flaps (NSF) were used, in 4 cases associated witha middle turbinate flap (MTF), and in 1 case supplemented with an inferior turbinate flap(ITF). Five cerebrospinal fluid fistulas (8%) were noted. Among patients with initial lesions, 7%presented an anosmia. Cadaveric group. The length of the NSF varied between 5.2 cm and 7.7 cmand the width ranged from 3 cm to 4.5 cm. The ITF provided an anterior---posterior distancebetween 4.2 cm and 5 cm, with a width between 1.2 cm and 2.8 cm. The mean length of MTFsvaried between 3.5 cm and 4.2 cm, with a width between 1.4 cm and 1.9 cm.Conclusion: The most versatile local flap for the reconstruction of skull base defects is the NSF,

and flaps pedicled to the posterolateral nasal artery offer an excellent alternative. © 2013 Elsevier Espana, S.L.U. All rights reserved.

� Please cite this article as: Gras-Cabrerizo JR, Gras-Albert JR, Monjas-Canovas I, García-Garrigós E, Montserrat-Gili JR, Sánchez delampo F, et al. Colgajos pediculados procedentes de la arteria esfenopalatina: estudio anatómico y quirúrgico. Acta Otorrinolaringol Esp.014;65:242---248.∗ Corresponding author.

E-mail address: jgras@santpau.cat (J.R. Gras-Cabrerizo).

173-5735/© 2013 Elsevier Espana, S.L.U. All rights reserved.

Pedicle Flaps Based on the Sphenopalatine Artery 243

PALABRAS CLAVEColgajos pediculados;Arteriaesfenopalatina;Base del cráneo;Cirugía endoscópica

Colgajos pediculados procedentes de la arteria esfenopalatina: estudio anatómico yquirúrgico

ResumenIntroducción: Los colgajos locales pediculados a la arteria esfenopalatina permiten reconstruiramplios defectos de la base del cráneo (BC).Material y métodos: De enero de 2008 a enero de 2013 se analizaron 64 lesiones con afectaciónde la BC intervenidos con un abordaje endonasal endoscópico que requirieron una reconstruc-ción con colgajos locales pediculados a la arteria esfenopalatina.

Adicionalmente se estudiaron cuatro fosas nasales correspondientes a dos cabezas de cadáverdonde se analizaron endoscópicamente las medidas y la flexibilidad de cada uno de los colgajos.Resultados: Grupo quirúrgico. Se emplearon 64 colgajos nasoseptales (CNS), en cuatro casosasociados a un colgajo cornete medio (CCM) y en un caso complementado con un colgajo delcornete inferior (CCI). Se evidenciaron 5 fístulas postquirúrgicas (8%). Un 7% de los pacientescon lesiones iniciales presentaron una anosmia definitiva.

Disección anatómica. La longitud del CNS varió entre 5,2 cm y 7,7 cm oscilando la anchuraentre 3 cm y 4,5 cm. El CCI presentó una distancia anteroposterior entre 4,2 cm y 5 cm yuna anchura entre 1,2 cm y 2,8 cm. La longitud media del CCM varió entre 3,5 cm y 4,2 cmcon una anchura entre 1,4 cm y 1,9 cm.Conclusión: El CNS es el colgajo local que presenta una mejor versatilidad en el sellado delos defectos craneales, siendo los colgajos pediculados a la arteria nasal posterolateral unaexcelente alternativa.© 2013 Elsevier Espana, S.L.U. Todos los derechos reservados.

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Introduction

The aim of reconstructive surgery of the skull base (SB) is toseal the surgical defect and separate the nasosinusal areafrom the cranial cavity, thus preventing the presence ofcerebrospinal fluid fistulas (CBF) and possible intracranialcomplications. The use of autologous, or heterologous freegrafts obtains excellent results in the repair of the major-ity of small cranial defects, in general under 1 cm.1---3 Forlarge defects, in patients who have had repeated surgery orpatients previously treated with radiation, the vascularised,local or regional flaps, provide vital tissue volume of greaterquality enabling more reliable reconstructions by minimis-ing scarring problems and tissue necrosis. Local endonasalflaps were previously used in different areas of the maxilo-facial region, such as in the repair of septal perforations,oronasal fistulas, in choanal atresia or reconstruction of thenasal pyramid.4---7 Its application in SB reconstruction is rela-tively recent, the flap designed by Hadad and Bassagasteguybeing the most popular at present. This NSF has been deci-sive for the advance and extension of these reconstructivetechniques.8,9 At present they seal extensive defects with apost surgical fistula percentage under 5%.3,10,11

The aim of this study is to describe our experience in SBreconstruction using local vascularised flaps, and study thecharacteristics of the main flaps from different branches ofthe sphenopalatine artery (SA) in corpses.

Material and Methods

From January 2008 to January 2013 a total of 93 lesionsaffecting SBs, which underwent surgery using endoscopic

nami

ndonasal approach (EEA) were diagnosed in our Skullase Unit. Patients who were not treated by pedicle flapeconstruction and patients diagnosed with a CBF fistulaere excluded from the study. 64 lesions were studied

n total with analysis of distribution by age and gen-er, anatomopathological diagnosis, type of surgery used,ifferent flaps used in reconstruction, and post surgicalomplications. Minimum patient follow-up was 6 months.

In addition, an anatomical study was made in four cadav-ric nasal cavities which had been prepared and preservedccording to the Thiel technique and with their blood ves-els perfused with latex, dextrin, and lead tetroxide.12,13

computerised tomography was carried out on the para-asal sinuses of two specimens using a 10 crown Somatomensation 10® (Siemens) multidetector tomography.

The cavity and SA were then identified and an NSF,8 aTF14 and an ITF15,16 were designed in each nasal cavity.he length, extent and the flexibility of each one was ana-

ysed by endoscopy. A malleable graduated dilator was usedor the different measurements. The NSF length was cal-ulated from the head of the inferior turbinate and fromhe nasal-limen nasi vestibule to the external third of thehoanal arch. The length from the head of the middleurbinate and the inferior turbinate up to its insertion inhe upper palatine apophasis was measured. To measureSF width the largest extension between the superior inci-ion, made approximately 1 cm inferior to the nasal cavityoof, and the inferior incision located in the alveolar ridgeas considered. In the middle nasal turbinate and inferiorasal turbinate the greatest distance between the superiornd inferior margin of the two was considered. A second

easurement was made in the ITF, increasing the inferior

ncision up to half of the nasal cavity floor. Finally, data were

244 J.R. Gras-Cabrerizo et al.

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igure 1 Nasoseptal flap and septal posterior right flap. The 2: posterior artery flap.

onfirmed by cutting the flaps from their vascular pediclend carrying out the same measures extranasally (Fig. 1).

esults

urgical Group

he mean age of the patients at diagnosis was 53, withges ranged between 16 and 81. 59% of patients (38/64)ere women and 41% (26/64) men. The different patholo-ies included 48 pituitary gland adenomas, 5 chordomas,

craniopharyglomas, 4 meningoceles, 2 basilar impressionsnd one meningioma. 33% (21/64) involved revision surgery.n 93% of interventions a transellar transsphenoidal approachas carried out (60/64), a transellar approach being used

n 5 cases, extending to the clivus, in 4 cases extended tohe planum sphenoidale and in 5 cases associated with aranspterygoid transmaxillary approach.

In 3 cases an extended transnasal approach was used2 transodontoid and one transclival approach). In 1 patient

transsphenoid approach was used to access the lateral wallf the sphenoid sinuses.

64 NSF were used. In four cases these were associatedith a MTF and in one case complemented with an ITF. In0 patients (16%) the flap was directly applied onto the surgi-al defect and in the other cases grafts of fascia lata and/orbdominal fat were applied prior to this.

5 postsurgical fistulas (8%) were detected. In the patients an NSF was used in reconstruction and in allases lumbar drain was used immediately after surgery. Thestulas presented in 3 macroadenomas operated on using

ransellar transsephenoid approach, in one craniopharyn-ioama treated by transplanum transsphenoidal approachnd one meningocele of the lateral sphenoid recess treatedy sphenoid approach.

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ary branches can be seen in the thickness of the septal mucous.

One patient underwent review surgery after presentingn epistaxis following the removal of the nasal packing. Thisas successful and flap visibility was not altered.

7% (3/43) of patients with initial lesions presented withnosinia. The 3 patients were operated on for an ACTH-roducing adenoma. Olfactory alterations in the reoperatedatients were not considered.

adaveric Group (Figs. 2---5)

he sphenopalatine cavity and its terminal branches weredentified in the four nasal cavities: the posterior septalrtery (PSA) and the posterior lateral nasal artery (PLNA).17

n 3 cases a common trunk was identified and in one nasalavity SPA division was performed in the pterygopalatineossa.

The results of the length and width of each flap are shownn Table 1.

xtension of the Reconstruction With the Differentlaps

he NSF area covered the whole area between the upperhird and medial planum sphenoidale clivus, includinghe sellar area. It could be applied separately throughout theribiform plate area, in the ethmoidal groove and envelopinghe whole clival area.

The MTF extended to the sellar region, the tuberculumellae region, the supper third of the clivus and covered thethmoidal groove region.

The extended ITF covered the whole area of the clivus

p to the sella turcica depression.

Table 2 shows the viability of each flap according to oururgical experience and the findings from anatomical dissec-ion.

Pedicle Flaps Based on the Sphenopalatine Artery 245

CM

CE

ANPLANPL

ASP

ASP

Figure 2 Endoscopic and computerised tomography view of terminal branches of the sphenopalatine artery in the left nasal fossa.ANPL: posterior lateral nasal artery; ASP: posterior septal artery; CE: ethmoid crest; CM: middle turbinate.

Accessory

ANPLMiddle

Inferior

Inferior

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ANPL

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Figure 3 Endoscopic and computerised tomography view

Discussion

Free grafts have been widely used as the option of choicein reconstructive head and neck surgery but their lowerreliability and quality resulted in their being progressively

itpo

Table 1 Vascularised Flaps: Length and Width Measurements.

NSF L1---L2 × A cm

Fossa 1 6.1---7.0 × 4.0

Fossa 2 6.2---7.1 × 3.1

Fossa 3 5.2---6.0 × 3.0

Fossa 4 6.4---7.7 × 4.5

A: width; A1: width including inferior meatus and fossa floor; L: lengtCCI: inferior turbinate flap; CCM: middle turbinate flap; NSF: nasosept

erminal branches of the left posterior lateral nasal artery.

eplaced by vascularised local or regional flaps. At present,

n large SB defects this has become the reconstructiveechnique of choice. In one recent meta analysis a lowerercentage of CBF (6.7%) fistulas were present in patientsperated on for large dural effects with vascularised flaps,

CCM L × A cm CCI L × A---A1 cm

4.0 × 1.5 4.2 × 1.3---2.43.5 × 1.4 4.6 × 1.3---2.54.2 × 1.9 5.0 × 1.4---2.83.6 × 1.5 4.7 × 1.2---2.2

h; L1: length to inferior turbinate flap; L2: length to limen nasi;al flaps.

246 J.R. Gras-Cabrerizo et al.

CM

ANPL

CCI

S CI

Figure 4 Lower turbinate with its vascularisation from the posterior lateral nasal artery in the left nasal fossa. The inferiorturbinate flat is observed, including inferior meatus dissection and fossa floor. ANPL: posterior lateral nasal artery; CCI: inferiorturbinate flap; CI: inferior turbinate; CM: middle turbinate; S: septum.

Nasoseptal

Middle turbinate

Inferiorturbinate

SP

AEP

NPL

Inferior

Middle

Accessory

Figure 5 Endoscopic view of the 3 pedicle flaps to the leftsphenopalatine artery. AEP: sphenopalatine artery; inferior:ip

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Table 2 Versatility of Each Vascularised Flaps.

Defect NSF CCM CCI

Selar YES YES NOPlanum sphenoidale YES YESa NOEthmoidal groove YES YES NOCribiform YES NO NOClivus YES YESb YES

CCI: inferior turbinate flap; CCM: middle turbinate flap; NSF:nasoseptal flaps.

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nferior turbinal artery; middle: middle turbinal artery; NPL:osterolateral nasal artery; SP: posterior septal artery.

ompared with the reconstruction with free grafts (15.6%).3

uccess of pedicle flaps requires appropriate anatomicalnowledge of vascularisation. The flaps dependent upon ter-

inal branches of PEA, PLNA and PSA are the most widely

sed endonasal flaps. Oscar Hirsch was the first one to use septal flap to endonasally close a postoperative CBF fis-ula in 1952.18 Notwithstanding, these first rotation flaps

1atb

a Tuberculum sellae area.b Upper third of the clivus.

ere simple, the vascular pedicle was not identified andhe flap rotated around a pivot with random vascularisation.adad and Bassagasteguy succeeded in popularising this flap

n the AEE context, with a detailed description of its design,otation and vascularisation.8

asoseptal Flap

he nasoseptal flap is the pedicle flap with the greatest ver-atility in SB reconstruction. In our study the flap lengthanged between 5.2 cm and 6.4 cm increasing to 7.7 cm whenhe anterior incision extended to the limen nasi. Pinheiro-eto et al.19 demonstrated a similar length, ranging between.8 cm and 8.6 cm between the anterior and posterior flapimit.

Shah RN et al.20 found a mean length of 6.22 cm in21

0 adults studied and Shin JM et al. a length of 7.7 cm

nd 7.4 cm in two patients analysed. In our dissectionhe NSF width ranged between 3 cm and 4.5 cm. It shoulde noted that it is possible to increase its amplitude by

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Pedicle Flaps Based on the Sphenopalatine Artery

increasing the inferior incision further than the maxil-lary crest, including the mucous membrane of the nasalfosse floor. In our anatomical study this technique was notcompleted. These dimensions lead to the longitudinal recon-struction of the anterior SB defect, of the sphenoid sinusesand the clivus in separate approaches. It is also possible tocover a wide defect extending from the posterior wall ofthe frontal sinus to the anterior wall of the sphenoid sinusor of the planum sphenoidale, the mean distance of whichis 42 cm and 5.44 cm respectively.19,20

Any anterior SB defect may therefore be transversallyreconstructed. Batra PS et al.22 demonstrated a meaninterorbitary distance in an anatomical study on level ofthe anterior and posterior ethmoid arteries of 2.35 cm and1.91 cm respectively, whilst Waitzman AA et al.23 discov-ered a mean distance between both medial orbitary wallsof 2.7 cm and 2.9 cm, in radiological analysis, including33 patients between 16 and 17 years of age.

Notwithstanding, if a major defect is to be reconstructed,which includes the whole anterior SB and the clivus, it maynot be sufficient owing to the fact that the distance rangesbetween 9.82 cm and 11.92 cm.19 In these cases it is advis-able to design a bilateral NSF, or complete it with otherpedicle flaps or with free flaps.

Other alternatives must be found when the NSF is con-sidered excessive or when it is not possible to use it, suchas in previously operated patients with extensive septalresections, or when the lesions to be treated include septalmucosa.

Turbinate Flaps

Pedicle flaps based on the PLNA are a good alternative toNSF. The PLNA descends vertically over the vertical apoph-ysis of the palatine, irrigates the lateral wall regions ofthe nasal fossa and joins up with the anterior and posteriorbranches of the ethmoid arteries. It presents two terminalbranches, one for the middle turbinate and the other for theinferior turbinate. In 15% of cases the inferior turbinate mayreceive supplementary irrigation from the palatine arterybranches of the descending palatine artery and those comingpreviously from the angular artery.24,25

The ITF presents an excellent anteroposterior distance,between 4.2 cm and 5 cm, its width being its main limitation,which ranges between 1.2 cm and 1.4 cm according to ourresults.

Amit M et al.16 obtained similar results with a meanlength and width of 4.8 cm and 1.8 cm respectively in11 corpses analysed. However, Harvey RJ et al.26 obtaineda similar length (5.4 cm), but with greater width (2.2 cm).This greater extension may be explained by the inferior flapincision, which can be increased by extending its dissectionto the inferior meatus and/or fossa floor. In our study wesucceeded in duplicating the flap width using this technique(Fig. 4).

This is an ideal flap for sealing defects in the clivus areaFortes FS et al.15 used ITF successfully in 3 patients to recon-

struct the clival area and in one patient with a sellar defect.Harvey RJ et al.26 demonstrated that it is the best flap forposterior SB defects but that it only covers 2/3 of the ante-rior cranial fossa.

247

In our experience, its limited rotation angle only reliablynables the reconstruction of defects in the clival area, dueo the tension from extension to the sellar and suprasellaegion.

The MTF is pediculed to the middle turbinate arterymerging in the majority of PLNA cases through thephenopalatine cavity. In 12% of cases this may occur inhe most distal section of the PLNA, adjacent to the inferiorurbinate tail.

The mean length of the middle turbinate ranges between cm and 4.7 cm with maximum width of 1.5 cm.14,27

In our series MTF length was similar, with a superioridth between 1.4 cm and 1.9 cm, due to the design of the

ame which uses both the medial surface and lateral sur-ace mucous. Prevedello DM et al.14 confirmed these findingsescribing a mean extension of 2.8 cm in the 12 flaps ana-ysed. In this study they demonstrated that the MTF canover sellar defects in 83% of cases and up to 100% ofefects which affect the planum sphenoidale or the eth-oidal groove.This flap presents the most technical difficulties, due to

natomical variations of the turbinate and fixture instabil-ty, which together with the presence of a thin and friableucous turbinate, hinders its subperiostic dissection. Sim-

larly to the ITF it has less flexibility compared with theSF. In our experience the MTF can separately cover sellarefects of the tuberculum sellae area, defects of the upperhird of the clivus and defects in the ethmoidal groove area.t can probably also reach the suprasellar area, but in ourissection we were not able to reliably reconstruct this area.

In our institution we always used the MTF as an additionalap in AEE reconstruction and never as the only flap.

The morbidity of these pedicle flaps depends on theiresign and size, with more frequent morbidity when therere crusts. In most cases this is related to septal mucousegeneration time used in the NSF, with mean time at

months.28 The design of these flaps, NSF and MTF, maylter the olfactory function.28,29 De Almeida JR et al.28 found

diminished sense of smell in 7.9% of patients and anosmian 1.6%. 7% (3/43) of our patients who had been operatedn for initial lesions presented anosmia.

onclusion

edicle flaps based on the SPA offer an excellent reconstruc-ive option in SB defects. The NSF is the most versatile withedicle flaps being used as a good alternative to PLNA whenSF cannot be used.

onflict of Interests

he authors have no conflict of interests to declare.

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