A novel technique for cheek mucosa defect reconstruction using a pedicled buccal fat pad and buccinator myomucosal island flap

Introduction 

When approaching buccal mucosa defects involving the cheek mucosa, the goals of the reconstructive surgeon must include preserving the mouth opening, avoiding trismus, restoring the internal lining, and considering the aesthetic outcome. Fasciocutaneous free flaps, locoregional pedicled flaps, and local flaps can be used to reconstruct cheek mucosa defects following tumors resection, depending on the size and site of the defect.1

Although microsurgical free flaps are currently the first choice for reconstructing several head and neck defects, buccal mucosa resections smaller than 8–10cm can easily be restored using a local or locoregional flap, reducing donor site morbidity and the lengths of surgery and hospitalization. However, the use of locoregional flaps, such as a temporalis myocutaneous pedicled flap2 or pedicled temporoparietal fascial flap,3 is limited by postoperative contracture, which can limit mouth opening or even lead to trismus. Local flaps have several advantages,4 but if the defect exceeds 5–6cm, they cannot provide an adequate amount of tissue for the reconstruction.

This paper presents a novel technique for reconstructing moderate-sized cheek mucosal defects that uses two local flaps: a pedicled buccal fat pad and a buccinator myomucosal island flap.

Case report and surgical technique 

We present a 55-year-old woman (Fig. 1) with a squamous cell carcinoma of the anterior left cheek. On clinical examination, the tumor measured about 6×4cm, with invasion limited to the cheek mucosa and oral commissure (Fig. 2). Preoperative computed tomography (CT) confirmed the clinical findings and excluded the presence of lymph node metastasis (the patient was staged as T2 N0 M0). During surgery, a selective neck dissection was performed, taking care to preserve the facial artery. In our experience, preserving the facial vein is not necessary because buccinator flap congestion does not occur when it is not preserved due to the very rich submucosal venous plexus and the limited amount of muscle tissue taken.

View Large Image Download to PowerPoint

Figure 1. Pre-operative picture of the patient.

View Large Image Download to PowerPoint

Figure 2. Pre-operative intraoral picture of the lesion.

The tumor resection involved the anterior cheek mucosa and part of the oral commissure (Fig. 3). After identifying the orifice of Stenon’s duct in the cheek, an incision was made about 0.5cm inferior to it as the superior margin of the flap, which involved healthy mucosa (Fig. 4). The facial artery was followed inferiorly and laterally during the dissection with the aid of a Doppler probe and dissected from the surrounding structures. The flap was then transposed anteriorly to fill the anterior part of the defect. A buccal fat pad pedicled flap was harvested and transposed posteriorly to the buccinator flap to reconstruct the posterior part of the defect (Fig. 5).

View Large Image Download to PowerPoint

Figure 3. Intra-operative picture of the defect following tumor resection.

View Large Image Download to PowerPoint

Figure 4. Intra-operative picture of the design of the buccinator myomucosal island flap.

View Large Image Download to PowerPoint

Figure 5. Intra-operative picture of the harvested flaps: the buccinator myomucosal island flap is transposed anteriorly, and the buccal fat pad flap is placed in the posterior part of the defect.

No complications took place and the patient was discharged from the hospital 4 days after the procedure. On follow-up for 8 months, no infection or resorption of the buccal fat pad was observed. No retraction of the transposed flaps developed and no trismus or limitation of the mouth opening occurred. The aesthetic results were excellent, without visible scars, skin retraction, or cheek depression (Fig. 6), and the internal lining was restored, with complete re-epithelization of the flap tissues (Fig. 7).

View Large Image Download to PowerPoint

Figure 6. Post-operative picture of the patient 8 months after surgery: no scars, neither retraction or depression on the cheek area occurred.

View Large Image Download to PowerPoint

Figure 7. Post-operative intraoral picture of the reconstructed cheek mucosa: all the surface has undergone re-epithelization with a complete restore of the internal oral lining and no limitation of mouth opening.

Discussion 

Progress in microsurgery, especially the introduction of the radial forearm fasciocutaneous free flap and anterolateral thigh perforator flap, has encouraged reconstructive surgeons to use such techniques to reconstruct various head and neck defects. However, the donor site morbidity and longer surgery and hospitalization may limit their application in patients with poor general health. Moreover, if the defect is limited to the mucosa and is smaller than 8–10cm, it can be reconstructed adequately using local or locoregional flaps.

Contracture, with the consequent restricted mouth opening, limits using some of the most popular locoregional flaps, such as the temporalis myocutaneous pedicled flap and pedicled temporoparietal fascia flap. The nasogenial flap5 has been widely applied to reconstruct oral defects, especially in oncology, because its rotation and overturning can be used to fill various defects.

Despite its versatility in reconstructing the oral cavity, nasogenial flaps have certain disadvantages as the tissues differ markedly from the resected tissues, causing scars on the face and limiting the ultimate aesthetic result. In addition, the donor site can heal with scar retraction, which can alter the facial harmony, even if the residual scarring is concealed in the nasogenial sulcus. Furthermore when the resulting tension is directed from the apex toward the internal canthus of the eye, ectropion may occur.

Local flaps allow the rapid reconstruction of several mucosal defects, with good results and minimal morbidity; however, if the defect exceeds 5–6cm, the use of a single local flap, such as a lingual flap, contralateral cheek flap, or pedicled buccal fat pad, may lead to retraction with a poorer aesthetic outcome and limited mouth opening.

The buccinator myomucosal island flap (BUMIF), introduced by Carstens et al.6 in 1999, is a useful, versatile technique for correcting defects in any part of the oral cavity, with good results and modest morbidity.7 The buccinator muscle has a rich vascular supply that can be used for flap harvesting. In 1999, Zhao et al.8 described two different buccinator myomucosal island flaps: one is based superiorly, supplied by the anterior buccal branches of the distal facial artery, and the second is a posteriorly based flap supplied by the buccal artery and the posterior buccal branch of the facial artery. Although this vascular anatomy requires preservation of the facial artery, oncological radicality is not compromised, but is guaranteed by a more meticulous neck dissection.

The buccal fat pad has been used as the donor site for flaps vascularized by branches of the internal maxillary, superficial temporal, and small branches of the facial arteries. These flaps offer several advantages such as intraoral harvest, easy, relatively fast surgery, low morbidity, and the capability to undergo re-epithelization within a few weeks. The main limitation of these flaps is that they can be used for certain defects only, principally for the posterior oral cavity due to their relative low mobility.9, 10

Approaching anterior cheek mucosa reconstruction, when the facial artery can be preserved during tumor resection, advancing the buccinator myomucosal island flap to the anterior part of the defect, near the oral commissure, allows easy restoration of the mucosa, with optimal results, avoiding retraction and contracture. Furthermore, the resected mucosa is replaced with similar tissue, optimizing the final outcome. The facial artery is easily identified and preserved with the help of a Doppler probe, while the submucosal plexus provides adequate venous drainage, even if the facial vein is sacrificed during the neck dissection.

The posterior part of the defect and the donor site can be reconstructed using the buccal fat pad, as the limitations of its application are avoided with the posterior placement of the flap and the limited amount of tissue harvested (Fig. 8).

View Large Image Download to PowerPoint

Figure 8. Picture that shows the surgical technique: the buccinator myomucosal island flap is pinstriped, buccal fat pad is pointed. The facial artery is showed entering the flap.

This new reconstructive technique can easily be used for reconstructing moderate-sized cheek defects, achieving optimal results: the internal mucosal lining is restored in few weeks without any retraction, contracture, or scars on the face limiting the aesthetic outcome and mouth opening.

Conflict of interest statement 

None declared.