© 2002 by the American Society for Dermatologic Surgery, Inc. • Published by Blackwell Publishing, Inc.ISSN: 1076-0512/02/$15.00/0 • Dermatol Surg 2002;28:190–194

This new feature will emphasize innovative and better ways to perform dermatologic surgery procedures. This ar-ticle should be based on some evidence-based literature, but may describe the author’s experience with a particularprocedure without being a typical clinical research article. The editor will consider ideas for topics.

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Nasalis Myocutaneous Island Pedicle Flap with Bilevel Undermining for Repair of Lateral Nasal Defects

Diamondis J. Papadopoulos, MD,* David B. Pharis, MD,* Girish S. Munavalli, MD, MHS,* Filippo Trinei, MD,

‡

and Anastassios G. Hantzakos, MD

§

Departments of

*

Dermatology and

‡

Plastic Surgery, Emory University School of Medicine, Atlanta, Georgia, and

§

Department of Otolaryngology, Head and Neck Surgery, University of Athens Medical School, Athens, Greece

background.

The superiorly based nasalis myocutaneous is-land pedicle flap with bilevel undermining is a recently de-scribed bipedicled flap used for repair of nasal tip and supratipdefects. This flap was used for the repair of small to medium-size defects of the nasal tip and supratip regions.

objective.

To describe a single-pedicled modification of thisflap for the reconstruction of lateral nasal defects at or abovethe alar groove.

methods.

With the use of diagrams and fresh cadaver dissec-tion, we demonstrate the method of preparing, raising, andplacement of this new flap. We further elucidate in an illustra-

tive way the efficacy of bilevel undermining as it is used forachieving greater flap mobility. Finally, we show representativecases with pre- and postoperative results.

results.

We describe the senior author’s 4-year experience inthe development of this flap.

conclusion.

The nasalis myocutaneous island pedicle flapwith bilevel undermining, a new method for repair of lateralnasal defects at or above the alar groove, yields excellent func-tional and cosmetic results. Bilevel undermining is a new andvaluable method of achieving greater tissue mobility in muscle-based flaps.

THE RECONSTRUCTION of nasal defects has beena challenge to surgeons since antiquity due to the com-plex subtleties of this midfacial structure. Myocutane-ous flaps are an important part of the cutaneous sur-geon’s repair options. In 1983 Rybka

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described alaterally based myocutaneous island pedicle flap forthe reconstruction of lateral supratip nasal defects thatwas based on the nasalis muscle. Of the 47 patientsstudied, the maximum defect size was 1.25 cm for sin-gle flap reconstruction, with six patients having un-dergone bilateral island pedicle flaps for defect sizesup to 2 cm.

In 1987 Constantine

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used a similar reconstructiveflap for defects with a maximum diameter of 1.5 cm.

These flaps were again laterally based and largely de-pendent on branches of the angular artery that sup-plies the nasalis muscle. In a series of 24 patients, mostunderwent dermabrasion to correct surface irregulari-ties resulting from the sebaceous character of the nose.

In 1990 Wee et al.

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described refinements of the na-salis myocutaneous flap for reconstruction of lateral su-pratip defects. The refinements consisted of Z-plasty,early dermabrasion, and placement of a bolster. Selectedpatients underwent dermabrasion at 6–8 weeks after theprocedure in order to improve the final cosmetic result.These flaps were again laterally based and were usedfor the surgical repair of defects ranging up to 1.5 cm.

Over the past 5 years the senior author has devel-oped a superiorly based nasalis myocutaneous islandpedicle flap with bilevel undermining for the recon-struction of nasal tip and supratip defects.

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The basicsof this newly described bipedicled flap can be easilyadapted to a single-pedicled approach in order to re-pair lateral nasal defects at or above the alar groove.We feel that bilevel undermining of myocutaneous flapsbased on the nasalis muscle provide for important inno-

D.J. Papadopoulos, MD, D.B. Pharis, MD, G.S. Munavalli, MD,MHS, F. Trinei, MD, and A.G. Hantzakos, MD have indicated no sig-nificant interest with commercial supporters.Address correspondence and reprint requests to: Diamondis J. Papa-dopoulos, MD, Emory University School of Medicine, Emory Clinic, Pe-rimeter Office, 875 Johnson Ferry Rd., Suite 300, Atlanta, GA 30342.

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vations in the reconstruction of nasal defects. We wishto describe the technique in raising, preparing, and plac-ing the superiorly based nasalis myocutaneous islandpedicle flap with bilevel undermining for repair of lat-eral nasal defects.

Regional Anatomy

This flap is a superiorly based myocutaneous flap and,as such, is a compound flap composed of muscle, fas-cia, subcutaneous fat, and skin. The skin of this flap issupported by the arterial supply to the nasalis muscle(the nasalis artery) and through the musculocutaneousperforators that pass obliquely through the epimysiumand directly into the subcutaneous fat (Figure 1). Themuscular support for this flap is the nasalis muscle,which consists of a transverse and an alar segment. Thetransverse segment arises lateral to the pyriform aper-ture, with its fibers passing superiorly and medially,merging on the dorsum of the nose to form a thin apo-

neurosis, which is attached to the corresponding mus-cle of the opposite side. This aponeurosis joins andforms a broader fusion with the aponeurosis of theprocerus muscle. The alar segment of the nasalis mus-cle arises above the connective tissue layer of the nasalala, as well as the minor cartilage. This segment at-taches to the deep surface of the skin at the nasolabialgroove and wraps around the inferior and lateral as-pects of the nasal ala. This alar part, along with the leva-tor labia superioris alaeque nasi muscle is responsiblefor nasal dilation, which occurs during inspiration (Fig-ure 1).

Surgical Technique

The flap is designed slightly smaller than the defect, byapproximately 10–15% (Figure 2). Skin incisions aremade down to the nasalis muscle and nasalis aponeuro-sis. Subsequently the superficial component of bilevel un-dermining is performed at the lateral incision of theflap. This is carried out between the subcutaneous fatlayer and the nasalis muscle (Figure 3). The extent ofthis initial undermining largely depends on the size ofthe flap that will be mobilized and can be carried lat-erally to the nasofacial transitional plane. After thisthe nasalis muscle is transected down to cartilage atthe medial flap margin. The deep component of bilevelundermining is then carried out between the undersur-face of the nasalis muscle and the periosteum or peri-chondrium of the dorsum and sidewall of the nose(Figure 4). Careful trimming of the distal edge of themuscle is performed to minimize bunching of the mus-cle inferiorly after flap placement. The skin at the base

Figure 1. Depiction of the musculocutaneous unit and distributionof the nasalis muscle.

Figure 2. A) Depiction of the lateral nasal defect and initial designof the flap. B) Fresh cadaver dissection demonstrating the lateralnasal defect and design of the flap.

Figure 3. A) Depiction of the superficial plane of bilevel undermin-ing between skin and muscle. B) Fresh cadaver dissection demon-strating the superficial plane of bilevel undermining with visiblemuscular support.

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of the triangular flap is then brought inferiorly and su-tured to the most distal segment of the defect with askin suture placed in a horizontal mattress or verticalmattress fashion, taking great care to approximate skinedges accurately. Subsequent suturing is performed us-ing skin sutures, with superficial bites of skin takenand with great care not to place suture through the un-derlying muscular pedicle. If there is redundant tissueprotrusion laterally or medially, this can be excised tocorrection and sutured meticulously so as to avoid in-version and depression of the sutured edges (Figure 5).Sutures are usually left in place for 5–7 days before re-moval. Figures 6–8 illustrate three lateral nasal defectsand the corresponding postoperative results in threerepresentative patients.

Discussion

The repair of nasal defects presents the cutaneous sur-geon with some of the most difficult challenges in der-matologic surgery. Because primary closure is rarely asatisfactory option, lateral nasal defects have tradition-ally been repaired with laterally based island pedicle ad-vancement flaps, and rhombic and bilobed transpositionflaps. Due to limitations encountered using the abovementioned flaps, we sought to investigate the utility of a

single pedicled modification of the superiorly based na-salis myocutaneous island pedicle flap with bilevel un-dermining, previously described for repair of nasal tipand supratip defects,

4

for repair of lateral nasal defects.The first report of a musculocutaneous flap is at-

tributed to Tansini

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in 1906. He describes the impor-tance of axial circulation to flaps, the musculocutane-ous perforators in compound flaps, and the latissimusdorsi musculocutaneous units. Since that time the con-cept of musculocutaneous flaps has been further eluci-dated elegantly by Orticochea

6

in 1972, by McCraw etal.

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in 1976, and impressively by Mathes and Nahai

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in1981. Over the past 25 years, these authors and manyothers have applied their experience and understandingin categorizing and surgically implementing the con-cept that skin can be sustained by its underlying musclethrough axial, as well as fascial cutaneous vessels. Theapplications of the experience gained by these authorsin the evolution of these flaps were predominantly usedin the surgical reconstructive approach of large truncaldeformities.

In 1988 Hagan and Walker

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described their experi-ence with the nasolabial musculocutaneous flap. In thatstudy they performed 20 of these flaps successfully. Theirflaps were in large part inferiorly based and in a con-comitant six cadaver investigation of the arterial sup-ply to the midface using blue or yellow latex prepara-tion injected into the facial artery, they found a relativepaucity of musculocutaneous vessels in the area of thenasalis and superiorly to it. In 1991 Wetzel and Mathes

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performed an elegant study that specifically looked at thearterial anatomy of the face with analysis of vascularterritories and perforating cutaneous vessels. In theirstudy they used selective ink injections, dissection andmeasurement of latex hardened perforators, and radio-

Figure 5. A) Depiction of the flap sutured in place. B) Fresh ca-daver demonstration of the flap sutured in place.

Figure 4. A) Depiction of both the superficial and deep plane ofbilevel undermining that has been achieved between subcutane-ous fat and nasalis muscle and the submuscular plane. B) Fresh ca-daver dissection demonstrating both the superficial and deepplane of bilevel undermining that has been achieved betweensubcutaneous fat and nasalis muscle and the submuscular plane.

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graphic examination of transverse sections of bariuminjected into cadaver specimens to define 11 vascularterritories of the face that showed three distinct pat-terns. Of these three, the central facial areas exhibiteda small densely populated musculocutaneous perforat-ing arterial system that emanated from a deep plexusformed by the facial and the supratrochlear arteriesand terminated in the subdermal plexus.

In 1980 Field

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described his experience with theuse of a subcutaneous bipedicled island flap for the re-pair of predominantly nonnasal defects. His descrip-tion of the plane of undermining used to affect repair ofthe defects depicted clearly demonstrates a strictly sub-cutaneous approach. The senior author’s clinical expe-rience with the use of the superiorly based nasalis myo-cutaneous island pedicle flap with bilevel underminingover the past 5 years has lead us to the conclusion thatthis flap is exceptional as a single-staged procedure inthe correction of difficult nasal tip and supratip defects.Less than 25% of these flaps need dermabrasion at 6–8weeks. The newly introduced method of bilevel under-mining is a critical component in the raising of this flap.

Undermining is carried out in two planes: subcutane-ous (between the subcutaneous fat and nasalis musclelateral to the flap) and submuscular (beneath the nasa-lis muscle and beneath the flap). This allows one tosuspend the island of skin on a distinct muscular slingthat allows for additional mobility and concomitantlyensures proper arterial supply to the cutaneous island.This type of undermining probably also prevents per-manent upward lift of the nasal tip in younger patientsthat is commonly seen in other nasal repairs due to thesecondary motion of the flap.

A simple, single-pedicled modification of the supe-riorly based nasalis myocutaneous island pedicle flapwith bilevel undermining provides a useful alternativein the repair of lateral nasal defects at or above thealar groove. The relative ease and rapidity of perform-ing this flap demonstrate the utility of the new conceptof bilevel undermining. The vascular support to the skinfrom the underlying muscular perforators ensures a richblood supply to the flap. As in the repair of nasal tip de-fects, the improved mobility provided by the singlemuscular sling prevents the upward lift of the nasal ala

Figure 7. A) Lateral nasal defect after tumor removal. B) Lateral view at the 12-week follow-up. Lateral nasal defect after tumor removal.C) Frontal view at the 12-week follow-up.

Figure 6. A) Lateral nasal defect after tumor removal. B) Lateral view at 8 weeks. C) Follow-up frontal view at the 8-week follow-up.

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postoperatively since there is very little secondary mo-tion of this flap. Extreme care and exact surgical tech-nique, in particular as it pertains to the bilevel under-mining, must be used in order to achieve maximummobility. Proper sizing of the flap (i.e., relative undersizing) is important in avoiding the trapdoor phenom-enon. Meticulous hemostasis and suturing technique,with the use of everting mattress-type sutures, is veryimportant at the inferior-most edge of this flap, as wellas when suturing at or near the alar groove for dog-ear correction in order to ensure the functional integ-rity of the ala. In our experience, patients with defectsat or below the alar groove may benefit from a morelateral placement of the flap. The lateral location pro-vides for slightly more secondary motion than the su-periorly based flap and may result in enough alar liftto prevent malfunction of the internal nasal valve inthese patients.

In conclusion, we feel the nasalis myocutaneous is-land pedicle flap with bilevel undermining is a usefulclosure option for lateral nasal defects. In addition, itis our assertion that bilevel undermining of myocuta-neous flaps adds another dimension to the reconstruc-tion of difficult anatomic facial defects. Our hope isthat through continued anatomic studies we will fur-ther define this new concept of tissue movement and

in so doing will open a new chapter in the use of myo-cutaneous flaps for facial reconstruction.

References

1. Rybka FJ. Reconstruction of the nasal tip using nasalis myocutane-ous sliding flaps. Plast Reconstr Surg 1983;71:40–44.

2. Constantine VS. Nasalis myocutaneous sliding flap: repair of nasalsupra-tip defects. J Dermatol Surg Oncol 1991;17:439–44.

3. Wee SS, Hruza GJ, Mustoe TA. Refinements of the nasalis myocu-taneous flap. Ann Plast Surg 1990;25:271.

4. Papadopoulos DJ, Trinci FA. Superiorly based nasalis myocutane-ous island pedicle flap with bilevel undermining for nasal tip andsupratip reconstruction. Dermatol Surg 1999;25:530–36.

5. Tansini L. Fopra it mio nuovo processo di amputazione delta mam-mella (coverage of the anterior chest wall following mastectomy).Jazz Med Ital 1906;57:141.

6. Orticochea M. The musculo-cutaneous flap method: an immediateand heroic substitute for the method of delay. Br J Plast Surg 1972;25:106–10.

7. McCraw JB, Dibbell DG, Carraway JH. Clinical definition of inde-pendent myocutaneous vascular territories. Plast Reconstr Surg1977;60:341–52.

8. Mathes SJ, Nahai F. Classification of the vascular anatomy of mus-cles: experimental and clinical correlation. Plast Reconstr Surg1981;67:177–87.

9. Hagan WE, Walker LB. The nasolabial musculocutaneous flap: clin-ical and anatomical correlations. Laryngoscope 1988;98:341–6.

10. Whetzel TP, Mathes SJ. Arterial anatomy of the face: an analysis ofvascular territories and perforating cutaneous vessels. Plast Recon-str Surg 1992;89:591–603.

11. Field LM. The subcutaneously bipedicled island flap. J DermatolSurg Oncol 1980;6:454–60.

Figure 8. A) Lateral nasal defect after tumor removal. B) Lateral view at the 6-week follow-up. C) Frontal view at the 6-week follow-up.