Plastic surgery

PART IV

HEAD AND NECK

CHAPTER 40  RECONSTRUCTION OF THE ORAL CAVITY, PHARYNX, AND ESOPHAGUS

MATTHEW M. HANASONO

INTRODUCTION

The oral cavity, pharynx, and esophagus are responsible for the critical functions of speech, mastication, swallowing, and maintenance of the airway. Head and neck reconstruction aiming to restore or preserve these functions is performed after surgical ablation of malignant tumors, congenital and acquired benign conditions, and traumatic injuries. The purpose of this chapter is to highlight the reconstructive challenges associated with each of these anatomic regions.

ANATOMY

The oral cavity is bounded by the lips anteriorly and the base of the tongue and soft palate posteriorly. Subsites of the oral cavity include the floor of the mouth, oral tongue (anterior two-thirds of the tongue, up to the circumvallate papillae), buccal mucosa, hard palate, mandibular and maxillary alveolar ridges, and retromolar trigones. The oral tongue is a critical structure for speech articulation and manipulating food. The hypoglossal (XII) nerve innervates all the muscles of the tongue except for the palatoglossus, which is innervated by the vagus (X) nerve. The facial (VII) nerve, via the chorda tympani, and the lingual (V3) nerve are responsible for taste and sensation of the oral tongue, respectively. Squamous cell carcinomas arising from the mucosa are the most common type of cancer affecting the oral cavity (see Chapter 30). Salivary gland cancers, arising from the submandibular, sublingual, and minor salivary glands, are the next most common.

The pharynx is divided into the nasopharynx, oropharynx, and hypopharynx. The nasopharynx extends from the skull base to the level of the soft palate. Most cancers of the nasopharynx are treated with combined radiation and chemotherapy, and surgical defects in this region are rare. The oropharynx extends from the soft palate to the hyoid bone. The soft palate, tonsils, tonsillar pillars, base of the tongue, and pharyngeal walls at this level are all considered parts of the oropharynx. The soft palate prevents nasal regurgitation, while the base of tongue and pharyngeal walls, which contain constrictor muscles, play a critical role in deglutition. The hypopharynx extends from the hyoid bone to the cricopharyngeus muscle, which is the most important component of the upper esophageal sphincter. The piriform sinuses, postcricoid area, and posterior pharyngeal wall comprise the hypopharynx. The hypopharynx may be the site of primary cancers, again most commonly squamous cell carcinomas, or may be involved in laryngeal cancers, which are more common, by direct extension.

The esophagus begins distal to the cricopharyngeus muscle and ends at the gastroesophageal junction. It is a mucosa-lined tube surrounded by a submucosa that contains secretory glands, an inner circular and outer longitudinal layer of muscles that are responsible for peristalsis, and an outer adventitia but not a true serosa. The walls of the proximal third of the esophagus contain striated muscle and the walls of the distal third of the esophagus contain smooth muscle, while the walls of middle third contain a mix of the two types of muscle. Squamous cell carcinoma is the most common cancer affecting the proximal esophagus, while adenocarcinoma is the most common cancer of the distal esophagus.

ORAL CAVITY

Floor of Mouth Reconstruction

Small- or partial-thickness defects of the floor of mouth can be skin grafted or repaired with a facial artery musculomucosal (FAMM) flap. The FAMM flap is based on the facial artery and includes a portion of the buccinator muscle in addition to the buccal mucosa and is usually useful for small defects (2 to 3 cm) that enable primary closure of the donor site.1 This vascularized flap is useful for the coverage of exposed bone and to prevent tethering of the tongue that may occur as a result of graft contracture.

The pedicled pectoralis major myocutaneous (PMMC) flap or pectoralis major muscle flap covered by a skin graft can be also used for extensive floor of mouth as well as many other oral cavity reconstructions. These flaps are based on the thoracoacromial artery and can reliably reach as high as soft palate. The skin paddle of the PMMC flap is reliable when designed to include adequate cutaneous perforators.2 Limitations of the pedicled pectoralis major flap include limited reach, neck contracture due to fibrosis of the proximal muscle, and the potential for an unsightly bulge in the neck. Despite these drawbacks, the PMMC and pectoralis muscle flaps are still frequently used in patients who are poor free flap candidates, as an additional flap in conjunction with a free flap to reconstruct massive defects, or as a secondary option in the event of a free flap failure. Anatomic studies suggest that a PMMC flap skin paddle centered over the 4th intercostal space is optimal in terms of reliability and reach.

Free flaps are the preferred method of reconstruction of floor of mouth defects in patients who have acceptable medical/ surgical risk factors. In these cases, free flaps typically have a more robust blood supply and a better arc of rotation than pedicled flaps. In addition, free flaps can be harvested from a variety of areas enabling the surgeon to transfer tissues that more closely resemble the resected structures. For example, the radial forearm fasciocutaneous (RFF) free flap is useful for moderate to large floor of mouth defects since it is thin and pliable, thus preventing compromised speech or swallowing due to excess bulk or tethering of the tongue. The RFF is based on the radial artery and is rapidly harvested with a long pedicle, thereby facilitating head and neck reconstruction.Drawbacks of the RFF flap are decreased circulation to the hand, risk of tendon exposure due to incomplete skin graft take, radial nerve injury, and an unfavorable donor site appearance in some patients. A suprafascial harvest, in which the fascia investing the forearm muscles and tendons is spared, may decrease donor site morbidity without compromising flap viability.3

For floor of mouth resections that result in substantial submandibular dead space, slightly bulkier flaps, such as the anterolateral thigh (ALT) free flap, are useful. The ALT free flap is based on skin perforators arising from the descending branch of the lateral circumflex femoral artery and vein and is particularly useful in head and neck reconstruction because it can be transferred either as a fasciocutaneous flap or as a myocutaneous flap depending on the reconstructive needs. When harvested as a fasciocutaneous free flap, it is usually intermediate in thickness between the RFF flap and the vertical rectus abdominis myocutaneous (VRAM) flap. The VRAM flap is based on the deep inferior epigastric vessels and is too bulky in most patients with isolated floor of mouth defects. Although the bulk of the VRAM can be decreased by harvesting it as a fasciocutaneous flap based on the deep inferior epigastric perforatoring (DIEP) vessels, even without the rectus abdominis muscle the DIEP flap is often thicker than the ALT free flap.

Buccal Mucosa Reconstruction

The goal of reconstruction for defects involving the buccal mucosa is to prevent cicatricial trismus. Primary closure can be used for small defects, and split- or full-thickness grafts can be used for moderate ones. For defects involving the majority of the buccal mucosa, a thin, pliable fasciocutaneous free flap such as the RFF flap is indicated to prevent scar contracture from limiting mouth opening. The ALT flap may also be used in thin patients and may have the advantage of decreased donor site morbidity as compared with the RFF. Alternatively, the ALT free flap can be thinned considerably at the time of surgery, taking care not to injure the perforator blood supply and the subdermal vascular plexus of the flap, or can be reduced secondarily. Buccal mucosa resections that result in through-and-through cheek defects often require reconstruction with flaps that can either be folded on themselves, de-epithelializing a portion of the flap to allow wound closure at the flap margin, or allow harvest with dual skin paddles. ALT and VRAM free flaps, and less commonly the RFF, can be designed with more than one skin paddle, allowing separate reconstruction of the buccal mucosa and external cheek skin with a single flap.

Tongue Reconstruction

Partial tongue defects can be closed primarily or with full-thickness skin grafts to prevent graft contracture. If primary closure or a graft is likely to result in significant tongue tethering or an inability to effectively obliterate the oral cavity space due to the size of the defect, a flap is usually indicated for closure. In practical terms, flaps are commonly required for defects approaching half the tongue and larger. Additionally, a through-and-through defect communicating with the dissected neck is usually best addressed with a flap to decrease the risk of fistula. The goal is to allow the residual tongue to contact the premaxilla and palate for speech articulation, as well as to be able to sweep and clear the oral cavity, and move food and secretions from anterior to posterior.4

For hemiglossectomy defects, a thin, pliable flap is needed to preserve tongue mobility, although a small amount of bulk is needed to obliterate the oral cavity dead space with the mouth closed and not create a funnel for secretions to drain directly into the larynx. Here again, most surgeons prefer the RFF free flap oriented such that the distal end of the flap is used to reconstruct the anterior portion of the tongue (Figure 40.1). Adequate flap width is needed to prevent tethering the tip of the tongue to the floor of mouth and to recreate a sulcus. Bulkier free flaps or the PMMC flap can also be used in more extensive resections; however, these options typically have inferior results in terms of speech and swallowing.

The strategy for reconstruction following near-total and total glossectomy is different. In these cases, a bulkier flap is required to reconstruct the greater volume of resection, and flaps such as the VRAM and ALT are commonly used. Swallowing and speech outcomes are better when the flap can be made convex into the oral cavity.5,6 To do so, it is helpful to design the flap to be somewhat wider than the oral defect, at least 8 to 9 cm in most cases, anticipating some atrophy of the flap with time, particularly if postoperative radiation will be administered (Figure 40.2). Additionally, many surgeons believe that laryngeal suspension using permanent sutures between the hyoid bone and mandible helps prevent prolapse of the flap and improve functional results. If at all possible, concave reconstructions creating a trough-like area should be avoided since pooling of oral secretions is associated with aspiration. In any case, the patient should be counseled preoperatively about the possibility of unintelligible speech, inability to swallow, and chronic aspiration.

Although the complex motor function of the tongue cannot be restored with current reconstructive techniques, sensory re-innervation of free flaps is well documented.7 The RFF free flap can be made potentially sensate by coapting the lateral antebrachial cutaneous nerve to the stump of the lingual nerve using standard techniques. Similarly, the ALT and RAM free flaps can be made sensate by anastomosis of the lateral circumflex femoral and intercostal nerves, respectively, to the lingual nerve. Sensory recovery is variable and likely dependent on a number of factors, including postoperative radiation. Interestingly, low volume free flaps, such as the RFF, have been shown to recover some sensation spontaneously even if nerve repair is not performed. It remains unclear, however, whether the amount of sensibility typically recovered secondary to nerve repair actually translates into improved speech or swallowing.

Reconstruction of Other Oral Cavity Structures

Tumors involving the mandible are relatively common and usually necessitate an osseous or osteocutaneous flap for reconstruction (see Chapter 38). Simple mandibular resections that include the mandibular ramus or posterior mandibular body are usually reconstructed with osseous free flaps such as the fibula or iliac crest. In contrast, complex retromolar trigone resections that include the condyle-bearing portion of the mandible and adjacent soft tissue structures, such as the lateral pharyngeal wall or external skin, are commonly reconstructed with bulky soft tissue flaps and usually lead to satisfactory cosmetic and functional results.8 Resection of the anterior mandible requires osseous flaps in most cases to restore facial projection. In some cases, two free flaps or a combination of a free and pedicled flap is necessary for massive defects involving soft tissue and bone resection.

Similar to mandible reconstruction, the posterior maxillary alveolar ridge and/or hard palate can be reconstructed with osteocutaneous free flaps or soft tissue free flaps. In addition, these defects may be amenable to skin grafting of the maxillary sinus and reconstruction (see Chapter 39) using a prosthetic obturator if the orbital floor is intact. Anterior defects of the maxilla, similar to the mandible, require rigid reconstruction either with an osseous flap or an obturator to restore facial projection. The temporalis muscle flap is occasionally useful in small defects of the hard palate or maxillary sinus. The reach of the flap can be extended by transposing it beneath the zygoma (the zygoma is temporarily removed and then replaced after flap rotation).9

PHARYNX

Many oropharyngeal cancers are more radiosensitive than oral cancers and radiotherapy is increasingly used as primary treatment in an effort to decrease morbidity secondary to surgical resection. Nevertheless, surgical resection is still indicated for extensive tumors, such as those that involved both the oral cavity and the oropharynx, and for recurrent cancers. The goals of reconstruction for the oropharynx include restoring continuity to the aerodigestive tract and replacing the volume of the tongue base to maintain swallowing function without aspiration.

Defects of the tonsillar fossa and pharyngeal walls can be reconstructed with a skin graft or allowed to heal by secondary intention when they are small and superficial. Deep wounds, such as those that result in communication with the neck contents, usually require a flap for closure. These defects are typically closed with low volume flaps such as the RFF and ALT since care must be taken to avoid interference with the airway or swallowing. Isolated base of tongue defects can sometimes be closed primarily. Partial defects, including those occurring in continuity with a tonsillar or retromolar trigone resection, are best reconstructed with a thin- to moderate-thickness fasciocutaneous free flap. Reconstruction of tongue base defects occurring as part of a near-total or total glossectomy requires bulkier flaps as discussed in the Oral Cavity section.

Most tumors involving the hypopharynx, including both primary hypopharyngeal tumors and extensive laryngeal tumors, are malignant and are treated by laryngopharyngectomy. In such cases, reconstruction involves restoring a part or the entire circumference of the hypopharynx, sometimes extending to the cervical esophagus, thus restoring the continuity between the oral cavity and the distal esophagus for swallowing. Microvascular free flaps have largely replaced regional pedicled flaps, such as the PMMC flap, due to their lower fistula rates. Free flap options include the jejunal free flap and fasciocutaneous free flaps, such as the ALT and the RFF free flaps.

The jejunal free flap is supplied by vascular arcades arising from the superior mesenteric artery and vein. A suitable segment located 20 to 30 cm from the ligament of Treitz is selected and the flap is isolated on a single arcade. The length of the jejunal segment required for the reconstruction is based on the defect in the pharynx and a segment measuring 10 to 15 cm is usually required. The flap can be split along the antimesenteric border to increase the diameter so that it is of suitable diameter to match that of the oropharynx and is inset into the defect in an isoperistaltic manner. Care must be taken to avoid redundancy as this may result in regurgitation and dysphagia.10 Warm ischemic time should be limited to less than 2.5 hours to avoid ischemia reperfusion injury. Intestinal continuity is restored in the abdomen and the wound is closed in a standard fashion.

FIGURE 40.1. Radial forearm flap for the tongue defect. A. A left hemiglossectomy defect following removal of a squamous cell cancer. B. Reconstruction of the defect with a radial forearm fasciocutaneous (RFF) free flap. C. Appearance 9 months after surgery.

FIGURE 40.2. Anterolateral thigh flap for total glossectomy defect. A. Reconstruction of a total glossectomy defect with an anterolateral thigh (ALT) free flap. B. Postoperative appearance 12 months after surgery followed by radiation therapy. Note the significant amount of atrophy.

The ALT free flap is another option for hypopharyngeal reconstruction.11 To create a 3 cm diameter “tube,” a 9.4 cm wide flap is required, based on the formula, circumference = p x diameter.Compared with the RAM free flap or the DIEP flap, the ALT free flap is usually thinner in most patients and a wider skin paddle, needed for reconstruction of circumferential defects, can usually be obtained. The RFF free flap is also useful for hypopharyngeal reconstruction, particularly in partial circumference defects or in obese patients with excessive thigh thickness. Some hypopharyngeal resections may spare a significant amount of the pharynx, and, occasionally, small or benign tumors can be resected with preservation of the larynx. In such cases, small fasciocutaneous flaps, such as the RFF free flap, are best suited to restoring pharyngeal continuity as a “patch.” For intermediate-sized noncircumferential defects, such as those that spare the posterior pharyngeal wall, the jejunal free flap can be split along its antimesenteric border or an appropriately narrower ALT free flap can be used for reconstruction. In addition, the PMMC flap is useful in medically high-risk patients who have acquired defects of the anterior wall of the pharynx.

An advantage of the jejunal free flap is the avoidance of an additional suture line when reconstructing circumferential defects. The primary disadvantage of the jejunal free flap is the need for a laparotomy, which may result in postoperative ileus, and the risks of anastomotic leakage of the repaired small intestine as well as potential late bowel obstruction due to adhesion formation. The ALT free flap is associated with minimal donor site morbidity, but may be excessively thick and difficult to inset in obese patients. Both flaps are reliable with low rates of postoperative pharyngocutaneous fistula formation.

Combined radiation and chemotherapy are increasingly used as primary therapy even for advanced laryngeal cancers. Thus, surgical resections tend to most commonly be performed for recurrent cancers, increasing the difficulty of reconstruction and the risk of postoperative complications, such as fistula. In addition, previously irradiated neck skin tends to contract after skin flap elevation and may be at high risk for wound healing problems if closed under tension. Suture lines may be especially tight along the tracheal stoma when a distal tracheal resection has been performed. In addition to potential exposure of the major neck vessels, a wound dehiscence in the region of the tracheal stoma or pharyngeal closure can result in significant further morbidity.

Reconstruction of the anterior neck skin often requires a second flap, either another free flap or a pedicled flap. The PMMC flap or pectoralis major muscle flap covered by a skin graft is frequently used to reconstruct the peristomal neck skin. Unilateral or bilateral deltopectoral flaps can also be used for this application. An elegant solution is to use a single flap to reconstruct both the pharynx and the anterior neck skin. The ALT free flap can often be designed with two skin paddles based on independent cutaneous perforating blood vessels that join together proximally within the main vascular pedicle, thus requiring only a single set of arterial and venous anastomoses to complete the reconstruction (Figure 40.3).12 When more than one perforator is not available, the vastus lateralis muscle can be included with the ALT free flap and skin grafted to reconstruct the neck skin defect. Alternatively, the ALT free flap or other fasciocutaneous free flaps can be partially de-epithelialized, and a portion of the skin paddle can be used to reconstruct the neck skin defect.

Vocal rehabilitation following laryngopharyngectomy can be accomplished by a number of methods, including use of an electrolarynx device or a tracheoesophageal puncture (TEP) prosthesis. The TEP prosthesis is inserted into a surgically created hole between the common wall of the posterior trachea and the cervical esophagus. The preferred location of this hole is about 1 to 2 cm below the superior rim of the tracheal stoma. In some cases, this hole is placed through the reconstructive flap. The creation of the TEP can be performed at the time of reconstruction or in a delayed manner, following flap healing. A one-way valve is part of the TEP prosthesis and allows shunting of air from the trachea to the pharynx and mouth for phonation when the stoma is occluded.

FIGURE 40.3. ALT flap after laryngopharyngectomy. A. A circumferential hypopharyngeal defect following laryngopharyngectomy for recurrent laryngeal cancer. B. An ALT free flap harvested from the right thigh with two skin paddles based on separate cutaneous perforating blood vessels arising from the descending branch of the lateral circumflex femoral artery. C. Reconstruction of the hypopharynx by creating a fasciocutaneous tube with the ALT free flap. D. The neck skin is reconstructed with a separate skin paddle of the ALT free flap. E. Postoperative barium swallow study demonstrating patency of the reconstructed hypopharynx.

ESOPHAGUS

Cervical esophageal defects are usually reconstructed by the same methods as hypopharyngeal defects, using jejunal free flaps or tubed fasciocutaneous free flaps. For defects of the thoracic and the entire esophagus, a number of options exist. Nonmicrosurgical methods include the gastric pull-up and colonic interposition procedures.13 In the gastric pull-up procedure, the stomach is mobilized and anastomosed to the proximal esophagus or pharynx via a posterior (orthotopic) or anterior (heterotopic) route. The gastric pull-up is the preferred method of thoracic and cervicothoracic esophageal reconstruction in most institutions.

When used for esophageal reconstruction, the ascending portion of the colon is often preferred. It is divided from the cecum and the transverse colon then interposed in the isoperistaltic direction between the cervical esophagus/hypopharynx and the stomach, which is connected by an end-to-side anastomosis. The right and middle colic arteries are ligated and the colonic segment continues to receive its blood supply from the inferior mesenteric artery via the marginal artery within the mesocolon. The cecum is reconnected to the transverse colon by an end-to-end anastomosis. The viable length of the colonic interposition segment can be extended by distal revascularization of its cervical end, resulting in a “supercharged” colon.

When gastric pull-up or colonic interposition are not options due to disease, inadequate length, or prior failure, another option is the supercharged jejunal flap.14 The jejunum is divided proximally between the first and second branches of the superior mesenteric artery arising beyond the ligament of Treitz. The second and third branches arising from the superior mesenteric artery are divided while the fourth branch is left intact to supply the distal portion of the mobilized jejunal conduit. The distal jejunum is divided and the distal jejunal flap is anastomosed to the posterior wall of the stomach with a circular stapler. Jejunal continuity is also restored by a stapled anastomosis. The proximal segment of the jejunal flap is connected to the cervical esophagus or hypopharynx, and a microvascular anastomosis between the proximal jejunal mesenteric arcade and the internal mammary vessels or branches of the external carotid artery and internal jugular vein is performed. In rare cases, very long tubed fasciocutaneous flaps have also been used for thoracic esophageal reconstruction.

RECIPIENT VESSEL DISSECTION

In most cases of previously untreated disease, recipient blood vessels of adequate length, caliber, and flow for microvascular anastomoses are readily available in the head and neck. Most reconstructive surgeons prefer to perform end-to-end anastomoses to branches of the external carotid artery, such as the facial or superior thyroid arteries, and to branches of the internal jugular vein when these vessels are available. End-to-side anastomoses to the external carotid artery and/or internal jugular vein are also reasonable options. The external jugular vein is also frequently used as a recipient vein, although care must be taken to ensure that external compression, such as by tight tracheostomy ties, is avoided postoperatively. However, in cases of prior irradiation and/or neck dissection, adequate recipient blood vessels may have been ligated or thrombosed.15 In other cases, extensive scar tissue formation may render dissection of the carotid and jugular vessels so perilous due to the risk of irreparable rupture that dissection is best avoided. In these cases, it is important to dissect the recipient vessels prior to preparation of the free flap such that the length of the pedicle required can be reliably calculated.

The transverse cervical artery and vein are excellent alternatives to the external carotid artery and internal/external jugular vein systems. These vessels are usually preserved during neck dissections. The transverse cervical artery arises medially in the neck from the thyrocervical trunk, or occasionally from the subclavian artery directly. The transverse cervical vein drains into the external jugular vein or the subclavian vein. The omohyoid muscle is a surgical landmark for the transverse cervical artery and vein, which are deep to the muscle within the supraclavicular fatty tissue.

The cephalic vein can also be an excellent source of venous drainage in the head and neck microvascular surgery. Advantages of the cephalic vein are that it provides a long pedicle, lies outside the zone of radiation or prior surgery, and can be dilated to a generous diameter, which simplifies microvascular anastomosis. The proximal cephalic vein can be located in the deltopectoral groove and traced distally into the upper extremity where it travels adjacent to the lateral bicipital groove.

The use of the internal mammary vessels has not commonly been reported for head and neck surgery but is well known in breast reconstruction with autologous free tissue transfer. The internal mammary vessels are usually located by removing the second or third costal cartilage after dividing the overlying pectoralis muscle.

The thoracoacromial artery and vein have also been described as potential recipient vessels in head and neck reconstruction. The thoracoacromial artery arises from the axillary artery and divides into acromial, deltoid, clavicular, and pectoral branches. Use of the pectoral branch of the thoracoacromial trunk for end-to-end anastomoses obviously prevents the use of the pedicled PMMC or pectoralis major muscle flap as a secondary flap for reconstruction.

References

1.  Pribaz J, Stephens W, Crespo L, et al. A new intraoral flap: facial artery musculomucosal (FAMM) flap. Plast Reconstr Surg. 1992;90:421-429.

2.  Rikumaru H, Kiyokawa K, Inoue Y, et al. Three-dimensional anatomical vascular distribution in the pectoralis major myocutaneous flap. Plast Reconstr Surg. 2005;115:1342-1352.

3.  Lutz BS, Wei FC, Chang SC, et al. Donor site morbidity after suprafascial elevation of the radial forearm flap: a prospective study in 95 consecutive cases. Plast Reconstr Surg. 1999;103:132-137.

4.  Chepeha DB, Teknos TN, Sharogorodsky J, et al. Rectangle tongue template for reconstruction of the hemiglossectomy defect. Arch Otolaryngol Head Neck Surg. 2008;134:993-998.

5.  Yu P. Reinnervated anterolateral thigh flap for tongue reconstruction. Head Neck. 2004;26:1038-1044.

6.  Kimata Y, Sakuraba M, Hishinuma S, et al. Analysis of the relations between the shape of the reconstructed tongue and postoperative functions after subtotal or total glossectomy. Laryngoscope. 2003;113: 905-909.

7.  Kimata Y, Uchiyama K, Ebihara S, et al. Comparison of innervated and noninnervated free flaps in oral reconstruction. Plast Reconstr Surg. 1999;104:1307-1313.

8.  Hanasono MM, Zevallos JP, Skoracki RJ, et al. A prospective analysis of bony versus soft-tissue reconstruction for posterior mandibular defects. Plast Reconstr Surg. 2010;125:1413-1421.

9.  Hanasono MM, Utley DS, Goode RL. The temporalis muscle flap for reconstruction after head and neck oncologic surgery. Laryngoscope. 2001;110:1719-1725.

10.  Disa JJ, Pusic AL, Hidalgo DA, et al. Microvascular reconstruction of the hypopharynx: defect classification, treatment algorithm, and functional outcome based on 165 consecutive cases. Plast Reconstr Surg. 2003;111:652-660.

11.  Yu P, Hanasono MM, Skoracki RJ, et al. Pharyngoesophageal reconstruction with the anterolateral thigh flap after total laryngopharyngectomy. Cancer. 2010;116:1718-1724.

12.  Yu P. One-stage reconstruction of complex pharyngoesophageal, tracheal, and anterior neck defects. Plast Reconstr Surg. 2005;116:949-956.

13.  Chen HC, Tang YB. Microsurgical reconstruction of the esophagus. Semin Surg Oncol. 2000;19:235-245.

14.  Ascioti AJ, Hofstetter WL, Miller MJ, et al. Long-segment, supercharged, pedicled jejunal flap for total esophageal reconstruction. J Thorac Cardiovasc Surg. 2005;130:1391-1398.

15.  Hanasono MM, Barnea Y, Skoracki RJ. Microvascular surgery in the previously operated and irradiated neck. Microsurgery. 2009;29:1-7.