The anatomical features and surgical usage of the submental artery

Transcription

1 Surg Radiol Anat (2005) 27: DOI /s ORIGINAL ARTICLE Yelda Atamaz Pinar Æ Figen Govsa Æ Okan Bilge The anatomical features and surgical usage of the submental artery Received: 8 March 2004 / Accepted: 7 September 2004 / Published online: 8 July 2005 Ó Springer-Verlag 2005 Abstract The skin characteristics make the submental region an available flap site for facial and intraoral reconstructions. For this reason, the anatomy of the submental region and the submental artery (SA) has gained in importance recently. The SA branches out from the facial artery at the level of superior edge of the submandibular gland. The SA runs anteromedially below the mandible and superficial to the mylohyoid muscle. It gives off some perforating branches to the overlying platysma and underlying mylohyoid muscle during its course. The terminal branches continue toward the midline, crossing the anterior belly of digastric muscle either superficially or deep, and end at the mental region in general. Some perforating arteries from the terminal branches supply the anterior belly of digastric muscle. This study aimed to describe the anatomical features of the SA and its branches to help in the preparation of submental arterial flaps. Keywords Submental artery Æ Flap Æ Submental region Æ Anatomy Introduction Reconstruction of complex facial defects is frequently challenging. The flap should be thin and pliable with good facial color match. The skin of the submental area has these important characteristics. Recently and independently, the submental island flap was developed and applied clinically in France [2, 13]. Martin et al. Y. Atamaz Pinar Æ F. Govsa Æ O. Bilge Department of Anatomy, Faculty of Medicine, Ege University, Izmır, Turkey F. Govsa (&) Ege U niversitesi Tıp Faku ltesi Anatomi Anabilim Dalı, TR Izmir, Turkey govsa@med.ege.edu.tr Tel.: Fax: described the submental island flap supplied by the submental vessels and presented clinical applications. The flap has been used for the reconstruction of facial defects by many surgeons [10, 13, 19]. The submental artery (SA) is the largest branch of the facial artery (FA) in the neck. The FA climbs superiorly leaning against the posterior face of the submandibular gland and gives off the SA behind or at the superior edge of the gland [19]. The SA runs anteromedially below the mandible and then runs superficial to the mylohyoid muscle to reach the chin. It gives off some branches to the submandibular gland and also perforating branches to the platysma and mylohyoid muscles [23]. One of the perforating branches of the mylohyoid muscle is larger than the others and it runs deep. This artery connects with the arterial circulation of the tongue and the floor of the mouth [15]. The terminal branches of the SA continue toward the midline and give off some perforating branches while crossing the anterior belly of the digastric muscle either superficially or deep [6]. The terminal branches curve to the chin and some of them join the arterial circulation of the lips via labiomental arteries or the inferior labial artery [20]. The submental region, including the digastric and submental triangles, is an ideal donor site for reconstruction of facial and intraoral defects. The skin of this region is thin and has a good facial color match. On the other hand, submentalbased flaps can have a long vascular pedicle to use in nasal and forehead reconstructions if the FA is included [5, 6, 7, 10, 11, 13, 14, 15]. Materials and methods The main aim of this study was to determine the anatomical features of the SA and blood supply to the submental region. For these purposes, we have discussed our anatomical findings in the surgical usage of the SA. We have therefore conducted a complementary anatomical study on the vascular pattern to improve the reliability of the study.

2 202 Twenty-five male human cadavers (between 40 and 60 years of age) were dissected bilaterally in the laboratory of the Anatomy Department of the Medical Faculty of Ege University. The cadavers were fixed in 10% formalin solution. After the skin dissection of the carotid triangle, the platysma muscle was released from the edge of the mandible with careful preservation of the FA and vein. The platysma was moved medially preserving its perforating arteries. The submandibular gland was pulled forward and the FA was exposed. Red-colored liquid latex was injected into the SA at the branching point. After the injection, the perforating branches and the termination of the SA were defined. While determining these findings, we took the studies of Martin et al. [13, 14], Faltaous and Yetman [6], Piehslinger et al. [18], Bavitz et al. [1] and Curran et al. [3] into consideration. The caliber of the SA at the bifurcation and the largest perforating branch to the mylohyoid muscle were measured with a digital caliper (0.02 mm Shock&Proof). Results The submandibular and submental triangles were dissected bilaterally in the 25 cadavers and in total there were 50 SAs. The external diameter of the SA varied between 0.82 and 2.80 mm (min max) with a mean of 1.80±0.46 mm on the left side, and between 1.02 and 2.72 mm (min max) with a mean of 1.88±0.48 mm on the right side. It was observed that the SA supplied the overlying platysma, the skin and the underlying mylohyoid muscle with its thin perforating branches. The SA gave off one to four anterior perforators that pierced the platysma. The platysma was moved, so that the SA was totally exposed. It was seen that it gave off four to six thin branches to the submandibular gland and two or three thin branches to the submandibular lymph nodes. All these structures were moved inferolaterally and the trace of SA over the mylohyoid muscle was observed. Although some terminal branches near the midline entered the anterior belly of the digastric muscle, some branches crossed the midline and anastomosed with the terminal branches of the opposite SA. In 10 samples (20%), one large terminal branch passed to the skin and anastomosed with the labiomental arteries or inferior labial arteries to join the labial arterial circulation. Only in one sample (2%), on the right side, did the SA curve posterior and inferior to the hyoid bone beneath the anterior belly of the digastric muscle and anastomose with a branch of the superior thyroid artery. The terminal branches of SA ran superficial to the anterior belly of the digastric muscle in 44% of cases (11 left, 11 right), while in the remaining 56% (14 left, 14 right) they ran deep (Figs. 1, 2, 3). A large branch of the SA perforating the mylohyoid muscle was found in 30 of the 50 dissections (60%). In the submandibular triangle, the SA gave off a large Fig. 1 The terminal branch of the submental artery (SA, arrow) curves to the chin and anastomoses with the labiomental or inferior labial arteries to join the labial arterial circulation. md, digastric muscle; vl, vertical labiomental artery; af, facial artery perforating branch which coursed deep to the floor of the mouth and anastomosed with the sublingual vessels. In all the cases, this large perforating artery originated from the proximal part of the SA, near the posterior belly of the digastric muscle or its tendon. The diameter of this large perforating artery varied between 0.50 and Fig. 2 A large branch of the SA (arrow) perforating the mylohyoid muscle. The terminal branches of the SA run superficial to the anterior belly of the digastric muscle. mm, mylohyoid muscle; md, digastric muscle; as, submental artery

3 203 Fig. 3 The terminal branches of the SA (arrow) run superficial to the anterior belly of the digastric muscle. md, digastric muscle; bm, basis mandibulae; af, facial artery 2.32 mm (min max) with a mean of 1.25±0.58 mm on the left, and between 0.42 and 2.42 mm (min max) with a mean of 1.48±0.65 mm on the right side. The SA became thinner after the branching of the large perforating artery. In the other 30 samples, a few thin perforating branches (looking like a dry tree) were observed, not just one main perforating branch (Fig. 4). Discussion The ideal flaps for resurfacing should be thin and reliable and have a good color match [13]. The flap should also be able to be dissected easily and have a large arc of rotation with minimal donor site morbidity [2, 8, 15]. Arc of rotation allows for reconstruction of anterior and lateral floor of mouth, buccal mucosa, retromolar trigon, glabellar region, and skin of the lower third of the cheek and parotid region [3, 10, 11, 13, 16, 17]. The submental area has many of these characteristics and has been used by several authors for facial and intraoral reconstructions. It is suitable for various reconstructive problems of head and neck because the flap has a long vascular pedicle once it is fully mobilized (Fig. 5) [4, 10, 19, 20, 22]. It would make an excellent flap for both Fig. 4 The terminal branches of the SA (arrow) run deep to the anterior belly of the digastric muscle, looking like a dry tree. md, digastric muscle; bm, basis mandibulae; gl, submandibular gland upper and lower lip reconstructions. It can also be very useful in nasal reconstruction and it may be a good alternative for the forehead flap. The donor site scar is concealed by the mandibular margin [7]. The type of flap can be selected (cutaneous, musculofacial or composite) depending on the clinical situation [3, 6, 14, 21]. The skin territories of the single-pedicled submental island flap are as large as 7 cm 15 cm [11]. The FA and SA provide the blood supply to the upper medial aspect of the neck. The anatomy of the platysma has been well described by Hurwitz et al. [8]. In their study, the SA provided direct cutaneous branching in 22 of 24 samples [8]. In the remaining two samples, the SA was not present and the lingual artery gave the cutaneous blood supply to this region. After giving off the submental branch, the FA wound around the inferior border of the mandible and at the anterior edge of the masseter entered the face. At this point, the FA sent relatively small and short vessels to the undersurface of the platysma [8]. The myocutaneous platysma flap derived its arterial blood supply predominantly from the submental branch of the FA [19]. Later, the myocutaneous platysma flap was advanced and used in intraoral

4 204 Fig. 5 The flap includes the anterior belly of the digastric muscle. (The terminal branches of the SA run deep to the anterior belly of the digastric muscle.) md, digastric muscle; sa, submental artery and facial reconstructions. The advantages of this flap are: the proximity to the surgical area, and the fact that the skin island pedicled by platysma muscle is easily harvested and transplanted to the defect. To observe the blood flow at the flaps, angiographic studies were advised [1, 5, 12, 18]. In 1997, Curran et al. [3] described the use of a new island flap based on the SA, which is ideal for the reconstruction of lower facial defects. The SA may pass deep to, through or above the anterior belly of the digastric muscle and it ends subcutaneously near the midline. The flap can be safely raised to include skin across the midline. In the surgical technique of the SA island flap, the length of the skin paddle can be designed between the two facial arteries. Dissection on the nonpedicled side is above the level of this muscle. On the pedicled side, the flap includes the anterior belly of the digastric muscle. First, the ipsilateral digastric muscle is raised, and then the dissection proceeds laterally on the surface of the submandibular gland until the FA is found [3, 22]. Demir et al. [5] used the submental island flap for beard and mustache reconstruction in male patients in addition to their applications of the flap. Hair-bearing scalp flaps have been used most often; however, the quality of the flap differs from that of the normal face. The mask-face appearance is an unacceptable result of these methods. On the basis of their clinical experiences and literature, Demir et al. suggested that the submental island flap surpasses other flaps in the reconstruction of the mustache or beard in male patients [5]. Merten et al. [15] described the submental region and the arteries and mentioned the diameter of the SA as mm. They used the SA island flap as an intraoral flap, external auditory canal flap and commissural flap. The chief benefit of this flap is undoubtedly the excellent cosmetic match with the facial skin and the well-hidden donor scar. Sterne et al. [19] also used the submental island flap in the intraoral and preauricular regions. Daya et al. used the submental island flap and the nasolabial flap for patients with defects of the lip and perioral region [4]. Large upper lip defects are traditionally treated with bilateral lip advancement flaps or Karapandzic flaps that borrow lateral cheek tissue. When lip defects include the columella, cheek, and/or perialar tissues, these flaps and traditional Abbe flaps may be inadequate. Kriet et al. [12] developed extended Abbe flaps for this reason. They designed Abbe flaps as extended to the submental region in some patients. Since the cutaneous vascular territory of the inferior labial artery and the anastomoses with the SA were important in the Abbe flap design, they demonstrated these structures by dissections in three fresh cadavers [12]. There is a similar condition in the study of Janssen and Thimsen [9]. They extended the SA island flap to the lower lip, and with a rotation they used this flap for esophagocutaneous fistula. The importance of the anastomoses between the SA and the inferior labial artery can be seen with the help of these studies [9]. Kitazawa et al. also showed that the bipedicled submental island flap was ideal for the reconstruction of the upper lip [11]. According to many textbooks of anatomy, the primary blood supply to the mandibular lingual gingiva and the floor of the mouth is derived from the sublingual branch of the lingual artery. However, today it is thought that these regions are also supplied by both the SA and the sublingual arteries. Bavitz et al. showed that in 60% of cases the SA had a large perforating branch which pierced the mylohyoid muscle [1]. In 93.2% of these cases, the diameter of the perforating branch was greater than the diameter of the SA. The perforating branch was 37 mm posterior to the menton. Ligation by compression of the SA at a point here may be considered. In the study by Bavitz et al., the sublingual artery was small in cases where a large perforating artery was observed [1]. In the study by Piehslinger et al., in three of the 15 heads it was observed that the sublingual artery originated from the SA bilaterally [18]. According to these studies, as the SA is a major arterial source to the floor of the mouth, standard hemorrhage control procedures require alteration. In particular, during implant surgery hemorrhage in the submandibular area can be stopped by applying broad pressure to the lower medial border of the mandible or by bimanual digital compression on the side where the FA crosses and the SA originates. However, anastomoses may indicate the need for ligation of both the facial and lingual arteries. The amount of blood from these arteries may accumulate in the submandibular space to compromise the airway. A

5 205 sign of impending distress is a protruding tongue. The tongue and epiglottis may be forced into the pharynx and larynx, closing off the trachea [1, 2, 7, 18]. In our study, the SA ran superficial to the anterior belly of the digastric muscle in 44% of cases (11 left, 11 right) while in the remaining 56% (14 left, 14 right) it ran deep. Faltaous and Yetman reported that in 70% of cases the submental vessels ran deep to the anterior belly of the digastric muscle, which should be included in the flap to prevent failure. In the remaining 30%, it ran superficial to the SA [3, 6]. In our study, the external diameter of the SA varied between 0.82 and 2.80 mm (min max) with a mean of 1.80±0.46 mm on the left side, and between 1.02 and 2.72 mm (min max) with a mean of 1.88±0.48 mm on the right side. Martin et al. [14] and Sterne et al. [19] gave this value as 2 mm (average), it was 2 3 mm (average) according to Bru e et al. [2] and was between 1.0 and 1.5 mm according to Faltaous and Yetman [6] and Merten et al. [15]. In all the samples in our study, the SA originated from the FA. Martin et al. [14] observed that in one of his 56 dissections the SA originated from the external carotid artery. Hurwitz et al. [8] did not observe the SA in two of their 24 samples. The SA predominantly provided the arterial blood supply to the superiorly based design of the myocutaneous platysma flap. In the study by Hurwitz, this region was supplied by the sublingual artery in two cases [8]. The submental island flap has potentially a very useful role in facial reconstruction. Its ease of access and shorter operative time needed for elevation are obvious advantages over free tissue transfer. Potential disadvantages of the flap include damage to the marginal mandibular nerve. There are a few limitations which preclude its use in certain situations, for example the thickness of the flap and the hairy skin in males. If the regions provided by the SA are determined in detail (such as the length, width and extension) the characteristics of the flap originating from the submandibular region can be better planned and also postoperative loss of the flap will be reduced. References 1. Bavitz JB, Harn SD, Homze EJ (1994) Arterial supply to the floor of the mouth and lingual gingiva. Oral Surg Oral Med Oral Pathol 77: Bru e E, Bey E, Cariou JL (2000) L arte re faciale. Rappel embryologique, anatomie descriptive et fonctionnelle d apres une revue de la litterature. Ann Chir Plast Esthet 45: Curran AJ, Neligan P, Gullane PJ (1997) Submental artery island flap. Laryngoscope 107: Daya M, Mahomya O, Madaree A (2001) Multistaged reconstruction of the oral commissures and upper and lower lip with an island submental flap and a nasolabial flap. Plast Reconstr Surg 108: Demir Z, Kurtay A, Şahin U, Velidedeog lu H, C elebiog lu S (2003) Hair-bearing submental artery island flap for reconstruction of mustache and beard. Plast Reconstr Surg 112: Faltaous AA, Yetman RJ (1996) The submental artery flap: an anatomic study. Plast Reconstr Surg 97: Flanagan D (2003) Important arterial supply of the mandible control of an arterial hemorrhage, and report of a hemorrhagic incident. J Oral Implantol 29: Hurwitz DJ, Rabson JA, Futrell JW (1983) The anatomic basis for the platysma skin flap. Plast Reconstr Surg 72: Janssen DA, Thimsen DA (1997) The extended submental island lip flap: an alternative for esophageal repair. Plast Reconstr Surg 102: Kim JT, Kim SK, Koshima I, Moriguchi T (2002) An anatomic study and clinical applications of the reversed submental perforator-based island flap. Plast Reconstr Surg 109: Kitazawa T, Harashina T, Taira H, Takamatsu A (1999) Bipedicled submental island flap for upper lip reconstruction. Ann Plast Surg 42: Kriet JD, Cupp CL, Sherris DA, Murakami CS (1995) The extended Abbe flap. Laryngoscope 105: Martin D, Baudet J, Mondie JM, Peri G (1990) A propos du lambeau cutane sous-mental en ilot. Protocole operatoire. Persperctives D utilisation. Ann Chir Plast Esthet 35: Martin D, Pascal JF, Baudet J, Mondie JM, Farhat JB, Athoum A, Gaillard PL, Peri G (1993) The submental island flap: a new donor site. Anatomy and clinical applications as a free or pedicled flap. Plast Reconstr Surg 92: Merten SL, Jiang RP, Caminer D (2002) The submental artery island flap for head and neck reconstruction. ANZ J Surg 72: O zc elik T, Aksoy S, Go kler A (1997) Platysma myocutaneous flap: use for intraoral reconstruction. Otolaryngol Head Neck Surg 116: Papadopoulos ON, Gamatsi IE (1993) Platysma myocutaneous flap for intraoral and surface reconstruction. Ann Plast Surg 31: Piehslinger E, Choueki A, Choueki-Guttenbrunner K, Lembacher H (1991) Arterial supply of the oral mucosa. Acta Anat 142: Sterne GD, Januszkiewicz JS, Hall PN, Bardsley AF (1996) The submental island flap. Br J Plast Surg 49: Uehara M, Helman JI, Lillie JH, Brooks SL (2001) Blood supply to the platysma muscle flap: an anatomic study with clinical correlation. J Oral Maxillofac Surg 59: Vural E, Suen JY (2000) The submental island flap in head and neck reconstruction. Head Neck 22: Yılmaz M, Menderes A, Barutçu A (1997) Submental artery island flap for reconstruction of the lower and mid face. Ann Plast Surg 39: Williams PL (1995). Gray s anatomy, 38th edn. International student edition. Churchill Livingstone, London, pp