[Submental island flap: a review of the literature]

Preservation of the Nerve to the Mylohyoid Muscle During Submental Island Flaps: An Anatomic Feasibility Study for Facial Nerve Reanimation Procedures

The submental island flap is an axial pattern pedicle flap widely used in head and neck surgery because of its ease and success. Indications of the submental island flap range from reconstruction for the malignant tumor resection to loss of temporal bone and facial skin due to trauma. Whereas, intraoperative facial nerve injury is not uncommon. We verified whether it was possible to localize the nerve to the mylohyoid muscle and reanimate the facial nerve during submental island flap procedures by preserving the mylohyoid muscle using human fresh cadaveric specimens. Six cadaveric heads were dissected and the position of the nerve to the mylohyoid muscle identified to the mylohyoid triangle documented. We identified the nerve to the mylohyoid muscle on all sides within the mylohyoid triangle and were able to separate the nerve from the submental island flap completely. Our results suggest that facial nerve reanimation using the nerve to the mylohyoid muscle can be used while reconstructing with a submental island flap in cases of intraoperative facial nerve injury.

Comprehensive Review of the Submental Flap in Head and Neck and Facial Reconstruction: What Plastic Surgeons Need to Know

ABSTRACT

Since its first introduction by Martin and colleagues (1993) and with further revisions by Sterne et al (1996), the submental artery flap (SMAF) has proven to be an effective, reliable, safe, and valuable option in head, neck, and facial reconstructive surgeries. The SMAF utilizes a long pedicle based on the submental artery, a branch of the facial artery, which provides good reach to the lower two-thirds of the face with excellent cosmetic outcomes. It also maintains a good skin color match for facial and cervical defects with a mostly hidden donor site scar (in the majority of cases the donor site can be primarily closed after raising the flap). Although the use of the SMAF is associated with high patient and surgeon satisfaction along with low rates of complications, disadvantages including flap thickness and the hair-bearing nature of the submental skin, which may be problematic for coverage of orofacial defects, especially in male patients. Although it has been almost 30 years since its introduction, and the SMAF has been successfully used in over 500 reported cases of pediatric and adult patients, a comprehensive review of the different aspects of the SMAF is lacking in the medical literature.

Alternatives to free flap surgery for maxillofacial reconstruction: focus on the submental island flap and the pectoralis major myocutaneous flap

Background

Microvascular tissue transfer (MTT) has been established as the gold standard in oral- and maxillofacial reconstruction. However, free flap surgery may be critical in multimorbid elderly patients and after surgery or radiotherapy, which aggravate microsurgery. This study evaluates indications and outcome of the submental island flap (SMIF) and the pectoralis major myocutaneous flap (PMMF) as alternatives to the free radial forearm flap (RFF).

Methods

This retrospective study included 134 patients who had undergone resection and reconstruction with SMIF, PMMF, or RFF at our department between 2005 and 2020. The level of comorbidity was measured with the Age-adjusted Charlson comorbidity index (ACCI). Primary outcome variables were flap success, complications, wound dehiscence, surgery duration, as well as time at the ICU and the ward (hospitalization). Chi-square tests, t-tests, and ANOVA were performed for statistics.

Results

24 SMIFs, 52 RFFs, and 58 PMMFs were included in this study. The flap types did not significantly differ in terms of flap success, complications, and healing disorders. The SMIF presented a success rate of 95.8% and was significantly more often used in elderly patients (mean age = 70.2 years; p < 0.001) with increased comorbidities than the PMMF (p < 0.01) and RFF (p < 0.001). SMIF reconstruction reduced surgery duration (p < 0.001) and time at the ICU (p = 0.009) and the ward (p < 0.001) more than PMMF and RFF reconstructions. PMMF reconstruction was successful in 91.4% of patients and was more frequently used after head and neck surgery (p < 0.001) and radiotherapy (p < 0.001) than SMIF and RFF reconstructions. Patients undergoing PMMF reconstruction more frequently required segmental jaw resection and had presented with advanced tumor stages (both p < 0.001). Nicotine and alcohol abuse was more frequent in the RFF and PMMF groups (both p < 0.001) than in the SMIF group.

Conclusions

The pedicled SMIF represents a valuable reconstructive option for elderly patients with increased comorbidity because of the shorter duration of surgery and hospitalization. On the other hand, the PMMF serves as a solid backup solution after head and neck surgery or radiotherapy. The rates of flap success, complications, and healing disorders of both pedicled flaps are comparable to those of free flap reconstruction.

Submental flap practice patterns and perceived outcomes: A survey of 212 AHNS surgeons

OBJECTIVES

To describe American Head and Neck Society (AHNS) surgeon submental flap (SMF) practice patterns and to evaluate variables associated with SMF complications.

METHODS

The design is a cross-sectional study. An online survey was distributed to 782 AHNS surgeons between 11/11/16 and 12/31/16. Surgeon demographics, training, practice patterns and techniques were characterized and evaluated for associations with frequency of SMF complications.

RESULTS

Among 212 AHNS surgeons, 108 (50.9%) reported performing SMFs, of whom 86 provided complete responses. Most surgeons who performed the SMF routinely reconstructed oral cavity defects with the flap (86.1%, n = 74). Thirty-seven surgeons (43.0%) experienced "very few" complications with the SMF. Surgeons who practiced in the United States versus internationally (p = 0.003), performed more total career SMFs (p = 0.02), and routinely reconstructed parotid and oropharyngeal defects (p = 0.04 and p < 0.001) with SMFs were more frequently perceived to have "very few" complications. SMF surgeons reported more perceived complications with the SMF compared to pectoralis major (p = 0.001) and radial forearm free flaps (p = 0.01). However, similar perceived complications were reported between all three flaps when surgeons performed >30 SMF. Among 94 surgeons not performing SMFs, 71.3% had interest in a SMF training course.

CONCLUSIONS

Practice patterns of surgeons performing SMFs are diverse, although most use the flap for oral cavity reconstruction. While 43% of surgeons performing the SMF reported "very few" complications, overall complication rates with the SMF were higher compared to other flaps, potentially due to limited experience with the SMF. Increased training opportunities in SMF harvest and inset are indicated.

Otolaryngology resident experience with supraclavicular, submental and other regional flaps in the United States

OBJECTIVE

Despite the resurgence in regional flap use, otolaryngology resident regional flap experience has been incompletely studied. We sought to characterize United States (US) otolaryngology resident exposure to, and perceptions of, supraclavicular flaps (SCFs), submental flaps (SMFs), and other regional flaps.

METHODS

An online survey was disseminated every two weeks to 106 US otolaryngology residency program directors for distribution to residents within their programs between August and October 2016. 121 surveys were returned of which 106 were sufficiently completed and eligible for data analysis.

RESULTS

Among residents with adequate responses, 52 were postgraduate year (PGY) 1-3 (junior) residents and 54 were PGY 4-7 (senior) residents. Senior residents participated in more pectoralis major flaps (mean: 8.1, 95%-CI: 6.5-9.8) compared to SCFs (mean: 1.5, 95%-CI: 1.0-2.0, p < 0.001) and SMFs (mean: 0.7; 95%-CI: 0.4-1.0, p < 0.001). Among senior residents exposed to SCFs, SMFs and pectoralis flaps, more individuals judged pectoralis major flaps as successful or very successful (96.2%, 95%-CI: 91.1-100%), compared to SCFs (64.3%, 95%-CI: 46.5-82.0%; p < 0.001) and SMFs (63.2%, 95%-CI: 41.5-84.8%; p = 0.001).

CONCLUSIONS

Senior otolaryngology residents were exposed to fewer SCFs and SMFs compared to pectoralis major flaps. Resident perception that SCFs and SMFs were not as successful as pectoralis major flaps should be investigated further.

Single-stage reconstruction of large defect of oral commissure and lips by submental artery island flap

Large defect of the lip and buccal mucosa created due to wide resection of the cancer is difficult to reconstruct and always a challenge. Such defects are complex as there is loss of outer skin, muscle, soft tissue, and inner mucosal lining. We report the use of submental artery island flap (SAIF) in the reconstruction of a large defect of oral commissure and buccal mucosa in a 70-year-old female with the diagnosis of verrucous carcinoma. The final outcome was optimal in terms of cosmetic and functional results. We obtained good lip seal without any problem in speech and swallowing. SAIF is an excellent alternative option for reconstruction of large complex defects of lips and oral commissure. It has a reliable vascular supply and provides a thin and pliable tissue for reconstruction in such critical area of face.

[Anatomic study of the submental artery relationships for submental flap raising]

INTRODUCTION

Submental flap is useful for intra-oral reconstructions and reconstructions of the lower two thirds of the face. Dissection is delicate because of a difficult exposure under the lower rim of the mandible, numerous collateral arterial branches and the proximity of the marginal branch of the facial nerve. The aim of our work was to propose anatomical landmarks in order to facilitate the submental flap raising.

MATERIAL AND METHOD

Ten bodies preserved in Biomet liquid were dissected bilaterally. The anatomic relationships between the marginal branch of the facial nerve and the mandible, the relationships of the submental artery, the amount and the location of its collateral branches were measured by means of a caliper.

RESULTS

The highest marginal branch observed was located 0.5 cm above the mandibular lower rim, while the lower one was located 0.6cm below this rim. The mean length measured between the facial artery at its crossing over the mandibular rim at the level of the pre-angular notch and the origin of the submental artery was 1.5cm. The average number of collateral branches was 3.6.

DISCUSSION

A skin incision made directly under the mandibular lower rim, as mentioned by some authors, may endanger the mandibular marginal branch of the facial nerve. Three positions of the submental artery in relation to the sub-maxillary gland are reported. The collateral branches are intended for gland, muscle, skin and bone. It is necessary to pay particular attention to the sub-lingual artery, an artery of big diameter that arises at 2.8cm on average from its origin and plunges towards the mouth's floor. It must not be followed at risk of clamping the thin pedicle destined to the digastric muscle. It is important to preserve the fat tissue around the submental pedicle in order to avoid venous congestion of the flap.