SURGICAL ANATOMY AND EMBRYOLOGY
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SURGICAL ANATOMY OF
THE NECK Grant W. Carlson, MD
FASCIAE OF THE NECK
Knowledge of the fascial layers of the neck is mandatory to extirpate cancer and treat infections of the head and neck. The fasciae surround muscles, vessels, and viscera, forming defined surgical planes and fascial envelopes. Metastatic squamous cell cancer of the head and neck follows predictable patterns, and these fascial planes enable resection with preservation of many vital structures. The fasciae of the neck were described in detail by Coller and Yglesia 4 and by Grodinsky and Holyoke. 8 The superficial fascia of the neck is composed of the platysma muscle, loose connective tissue, fat, and small unnamed nerves and blood vessels. The platysma is a voluntary muscle that is innervated by the cervical branch of the facial nerve (Fig. 1). It has varying degrees of development among individuals. It covers the major portion of the anterolateral surface of the neck, extending from the upper thorax and shoulder to the mandible. It covers the upper portion of the pectoralis major and deltoid muscles and blends with the muscles of facial expression as it passes over the mandible. The anterior borders are in close approximation below the chin but are more laterally placed at the level of the clavicle. The muscle may be included in elevating skin flaps to improve vascularity. Superficial lymphatic channels lie above the muscle, and removal would require skin excision. The cutaneous nerves of the neck and the external and anterior
From Emory University School of Medicine; and the Veterans Affairs Medical Center, Atlanta, Georgia
SURGICAL CLINICS OF NORTH AMERICA VOLUME 73 • NUMBER 4· AUGUST 1993
Figure 1. The platysma muscle forms the superficial fascia of the neck.
jugular veins lie between the platysma and the deep cervical fascia. The deep cervical fascia consists of areolar tissue that supports the muscles, vessels, and viscera of the neck. In certain areas it forms well-defined fibrous sheets called the investing layer, the pretracheallayer, and the prevertebrallayer (Fig. 2). The investing layer of the deep cervical fascia arises from the ligament nuchae and the spines of the cervical vertebrae and courses forward to completely surround the neck. It is attached to the external occipital protuberance, mastoid process, and zygoma. The investing layer envelops the trapezius and sternocleidomastoid (SCM) muscles and the parotid and submaxillary glands. At the anterior border of the SCM muscle, it contributes to the anterolateral wall of the carotid sheath and continues as a single layer to the midline. The pretracheal layer splits into an anterior portion that envelops the sternohyoid and sternothyroid muscles, and a posterior layer that envelops the thyroid gland, forming the false capsule of the gland. Below, it extends into the thorax and blends with the fibrous pericardium. Laterally, it blends with the carotid sheath and with the investing layer beneath the SCM. The carotid sheath contains the common and internal carotid arteries, internal jugular vein, and the vagus nerve. The nerve lies between and beneath the vessels. The deep cervical group of lymph
SURGICAL ANATOMY OF THE NECK
Sternocleidomastoid Muscle ~~i--=COiM--- Pretracheal
Layer Investing Layer
. .~,.... Trapezius Muscle
Figure 2. The deep cervical fascia is composed of the investing, pretracheal, and prevertebral layers.
nodes is found along the internal jugular vein within the sheath. Removal of the nodes can be facilitated by removal of the internal jugular vein as described in a classic radical neck dissection. Careful fascial dissection can remove the nodes without vein sacrifice in a procedure called a modified neck dissection. The prevertebral or deep layer encircles the muscles attached to the vertebral column: splenius capitis, levator scapulae, and the anterior, middle, and posterior scalene muscles. The deep cervical lymphatics are embedded in the loose connective tissue between investing and deep layers of the deep cervical fascia. TRIANGLES OF THE NECK
The SCM divides the neck into two large triangles: anterior and posterior (Fig. 3). It is attached to the lateral surface of the mastoid and the superior nuchal line of the occipital bone. Inferiorly it divides into two heads inserting on the clavicle and the sternum. At the anterior margin of the SCM, thickened fascia attaches to the angle of the mandible forming an angular band called Charpy's band. This band must be released to expose the tail of parotid and carotid vessels. The anterior triangle is formed by the anterior edge of the SCM, the midline of the neck from the manubrium to the symphysis of the mandible, and the inferior margin of the mandible. It is composed of four smaller triangles: submental, submaxillary, carotid, and muscularo (Fig. 3).
Figure 3. The sternocleidomastoid muscle divides the neck into anterior and posterior triangles. The anterior triangle is composed of four smaller triangles.
The submental triangle is bounded laterally by the anterior belly of the digastric muscle, inferiorly by the hyoid bone, and medially by the midline of the neck. The floor is composed of the mylohyoid muscle. Within the triangle is the terminal portion of the submental artery and a few submental lymph nodes. These nodes drain the anterior part of the tongue, floor of mouth, and the gingiva. The submaxillary triangle is formed by the anterior and posterior bellies of the digastric muscles and the inferior border of the mandible. This area has the most complicated anatomy in the neck and has clinical importance in treating tumors of the submandibular gland as well as metastatic disease from the anterior tongue and floor of mouth. 19 The roof is formed by the skin and the platysma muscle. The floor is composed largely of the mylohyoid muscle and a small amount by the hyoglossus muscle and the middle constrictor of the pharynx. The carotid triangle is formed by the anterior border of the SCM muscle, inferiorly by the superior belly of the omohyoid muscle, and superiorly by the greater cornu of the hyoid bone and the posterior belly of the digastric muscle. The floor is formed anteriorly by the thyrohyoid muscle and posteriorly by the middle and inferior constrictors of the pharynx. Passing superficial within the triangle are tributaries of the common facial vein, greater auricular nerve, and the cervical branch of
SURGICAL ANATOMY OF THE NECK
the facial nerve. The superior thyroid, occipital, and ascending pharyngeal branches of the external carotid artery arise within the triangle. The muscular triangle lies below the hyoid bone. It is formed anteriorly by the midline of the neck, superiorly by the superior belly of the omohyoid muscle, and inferiorly by the anterior border of the SCM muscle. The floor is composed of the sternohyoid and the sternothyroid muscles. Beneath the floor lies the thyroid gland, larynx, trachea, and esophagus. The anterior jugular veins course beneath the platysma muscle on either side of the midline. Just above the suprasternal notch, the veins unite, and then pass laterally beneath the SCM to drain into the external jugular vein. The SCM and trapezius muscles attach on a continuous line extending from the external occipital protuberance along the superior nuchal line to the mastoid process. The proximity of the attachments forms the apex of the posterior triangle. The anterior and posterior boundaries are these two muscles, and the base is the middle third of the clavicle. The floor is formed by the splenius capitis, the levator scapulae, and the scalenus medius muscles covered by prevertebral fascia. The roof is formed by the overlying skin; the platysma muscle is present only in the anterior part. Its absence makes it difficult to develop skin flaps in the posterior neck. The triangle contains the third part of the subclavian artery, the transverse cervical artery, the suprascapular artery, and the occipital artery. The external jugular vein courses obliquely through the triangle to drain into the subclavian vein. Difficulty arises in dissection of the most inferior portion of the triangle, where troublesome bleeding may be encountered. The inferior belly of the omohyoid muscle serves as an important landmark. No important structure other than the external jugular vein is found until the muscle is divided. The spinal accessory nerve is the most important structure found in the posterior triangle. It exits the jugular foramen, crossing ventral to the internal jugular vein and deep to the posterior belly of the digastric muscle. It lies deep to the SCM and divides within the muscle to supply it, and it continues through the lateral neck on the levator scapulae muscle to innervate the trapezius muscle. The nerve can be identified as it enters the deep surface of the SCM approximately 4 cm below the mastoid. It can also be found at Erb's point, just superior to where the greater auricular nerve surfaces from behind the SCM (Fig. 4). The nerve enters the deep surface of the trapezius approximately two fingerbreadths superior to the clavicle.
The submaxillary gland and associated lymph nodes fill the triangle overlapping the digastric muscles and extending upward deep to the mandiblel l (Fig. 5). Differentiating gland from lymph nodes can be difficult. The gland sends a prolongation of tissue with the submaxillary or Wharton's duct under the mylohyoid muscle (Fig. 6). The duct opens into the mouth on the side of the frenulum of the tongue. Superficial to
Figure 4. Erb's point is an important landmark in the posterior triangle.
FaCiaIV.( ~~~;::Mir\ Facial a.
Figure 5. The contents of the submaxillary triangle are illustrated just deep to the platysma muscle.
SURGICAL ANATOMY OF THE NECK
....;.--- Stylohyoid m.
Posterior BellY Digastric m: / \\1'
Figure 6. The superficial portion of the submaxillary salivary gland has been removed to reveal structures deep within the triangle.
the gland, the facial vein crosses the submaxillary triangle to reach the anterior border of the mandible. The facial artery enters the triangle under the posterior belly of the digastric and stylohyoid muscles. It ascends to emerge above or through the upper border of the gland. The marginal mandibular branch of the facial nerve courses through the triangle beneath the platysma muscle. It is the only important structure encountered above the digastric muscle in a submaxillary dissection. The course of the nerve is variable and it frequently has multiple branches. Dingman and Grabb 6 found the nerve to be above the anterior ramus of the mandible in 81 % of their cadaver dissections. In the author's experience, the nerve loops below the mandible to a varying degree in most patients. Skandalakis et aP9, 20 reported that in 50% of the cases, the mandibular branch is above the mandibular border, therefore outside of the submaxillary triangle. It courses over the facial vessels as it travels upward to supply the depressor anguli oris and the depressor labii inferioris muscles. To prevent injury during neck dissection, the facial vessels are divided below the nerve and used to retract the nerve above the mandible. Lymph nodes are present about the vessels, and the nerve may need to be sacrificed to facilitate removal. Injury to the nerve can result in facial asymmetry and occasional drooling. The hypoglossal nerve descends between the internal jugular vein and the internal carotid artery, giving branches to the thyrohyoid and geniohyoid muscles, and supplies the superior limb of the ansa cervicalis, which supplies the infrahyoid strap muscles. It enters the triangle deep to the posterior belly of the digastric. It lies on the surface of the hyoglossus muscle and courses deep to the mylohyoid muscle to supply motor function to the tongue.
The lingual nerve, a branch of the mandibular nerve, is found under the border of the mandible on the hyoglossus muscle above the hypoglossal nerve. It is attached to the submaxillary gland by the submaxillary ganglion and courses deep to the mylohyoid muscle to provide sensation to the anterior tongue and floor of mouth (Fig. 7).
The lymphatic system of the head and neck was elegantly described by Rouviere18 in 1938. One third of the lymph nodes in the body are concentrated in the head and neck region. Detailed knowledge of the cervical lymphatics is necessary to diagnose and treat cancer of the head and neck. The superficial lymphatics course in the subcutaneous tissue intimately associated with the skin and superficial fascia. They perforate the superficial layer of the deep cervical fascia to communicate with the deep cervical nodes. These superficial nodes are frequently involved in cervical metastases, especially during the late stages, but are of little significance from the surgical standpoint. Superficial lymphatics involved with cancer cannot be removed without resection of large areas of skin, and their involvement implies a dismal prognosis. At the junction of the head and neck are groups of nodes named for their location: occipital, retroauricular, parotid, submandibular, submental, and retropharyngeal nodes (Fig. 8). These groups of nodes form a cervical ring that is the first-echelon drainage for the scalp, the face, and the mucous membrane of the upper aero digestive tract. Involvement of
Figure 7. The entire submaxillary gland is removed to demonstrate the floor of the triangle.
SURGICAL ANATOMY OF THE NECK
Figure 8. The deep cervical lymphatics are named for their location. The most important groups course along the internal jugular vein and the spinal accessory nerve.
a particular nodal group provides a clue as to the location of the primary lesion as depicted. The lymph nodes in the posterior cervical triangle course along the spinal accessory nerve. The upper nodes in this group are in the anterior neck, where there is a coalescence of nodes from both the upper jugular and spinal accessory group. These nodes drain the nose and upper extent of the aerodigestive tract. The spinal accessory nodes are infrequently involved in metastases from the oral cavity, but preservation may be impossible because of their proximity to the anterior jugular chain. Small nodes course along the transverse cervical vessels, communicating with both the spinal accessory and jugular chains. They receive drainage from the skin of the lateral neck and chest. The nodes in this group are more frequently involved by metastatic carcinoma from below the claviclebreast, lung, kidney, stomach, or lower gastrointestinal tract-than from the neck itself.1 The lymphatics of the anterior triangle course along the internal jugular vein. They are embedded in the fascia of the carotid sheath, and the majority lie on the anterolateral aspect of the vein. In the upper neck are found the jugulodigastric nodes, which are below the posterior belly of the digastric muscle behind the angle of the mandible. This important surgical area is a frequent site of cervical metastases. The spinal accessory
nerve must frequently be sacrificed to adequately remove metastatic nodes in this area. The middle jugular nodes are found where the omohyoid muscle crosses the carotid sheath. These drain the middle part of the aerodigestive tract and thyroid. The inferior nodes are below the omohyoid and drain the thyroid, esophagus, and trachea. Treatment of metastatic cancer in the neck was first described by Crile3 in 1906. Martin et al13 standardized the radical neck dissection in a review in 1951. They described the systematic removal of the SCM muscle, internal jugular vein, and spinal accessory nerve. They believed that removal of the spinal accessory nerve was mandatory to adequately remove the cervical lymphatics. Since then, modifications of the radical neck dissection have been attempted by Bocca/ Jesse,I° and others to preserve these structures without compromising cancer control. Advantages include preservation of shoulder function, protection of the internal carotid artery, better aesthetic contour, and the ability to perform simultaneous bilateral procedures.
Because for all practical purposes the neck does not exist in the embryo, a discussion about the embryogenesis of the neck is impossible. The embryologic history of this region is the isolated history of each of the organs that are contained in this area and, specifically, the embryogenesis of the pharyngeal apparatus and its derivatives, such as the thyroid, parathyroid, thymus, and so on. Pouches, clefts, and arches appear and disappear; the esophagus and vessels are elongated, whereas other embryologic entities, such as the diaphragm, descend. Early in the sixth week, solid epithelial buds of ectodermal origin form the wall of the primitive mouth and invaginate into the surrounding mesenchyme. To start, a groove appears that later becomes a tunnel. The future parotid gland is formed in the blind end of the tunnel by proliferation, budding length, and extensive branching. The end of the solid ducts forms the secretory acini. The mesenchyme is responsible for the genesis of the capsule and the connective parotid tissue. Later, in fetal life, the solid epithelial buds and acini become hollow. All the salivary glands have a similar embryogenesis. The facial nerve and the parotid ductules begin a very close association early in the fetal period, practically embracing each other in such a way that the description of McKenzie15 is very characteristic and beautiful: "a creeper weaving itself into the meshes of a trellis-work fence." The parotid gland is the most common site for salivary neoplasms, accounting for 80% of the total. The majority of these tumors are benign, but precise knowledge of the anatomy is necessary to avoid facial nerve injury during parotidectomy. The parotid gland is an irregular, wedgeshaped organ that envelops the posterior border of the ascending ramus of the mandible (Fig. 9). On its superficial surface it extends medially to cover a portion of the masseter muscle. The body of the gland fills the
SURGICAL ANATOMY OF THE NECK
Figure 9. The parotid gland covers the ascending ramus of the mandible.
space between the mandible and the surface bounded by the external auditory meatus and the mastoid process. Deep to the ascending ramus, the gland extends forward to a variable degree, lying in contact with the medial pterygoid muscle. Just below the condylar neck, above the attachment of the medial pterygoid to the bone, the gland extends between the two. In the region of the condyle, the gland lies between the capsule of the temporomandibular joint and the external acoustic meatus. Laterally, at the junction of the mastoid process and the SCM muscle, the gland lies directly on the posterior belly of the digastric muscle, the styloid process, and the stylohyoid muscle. These structures separate the gland from the internal carotid artery, internal jugular vein, and cranial nerves IX to XII. Practically, these anatomic entities form the parotid bed, which is related to the so-called deep lobe of the parotid gland. Several important anatomic entities may be remembered with the mnemonic VANS, where V = internal jugular vein (one Vein); A = external and internal carotid arteries (two Arteries); N = the last four cranial Nerves (IX, X, XI, XII): glossopharyngeal nerve, vagus nerve, spinal accessory nerve, and hypoglossal nerve; and S = Styloid process plus three muscles: styloglossus, styloglossues pharyngeus, and styloglossus hyoid. As for the topographic anatomy of these structures, remember: Vein = deep in the floor of the parotid bed; Artery = anterior to the vein; Nerves are the glossopharyngeal = related to the S muscles, vagus = between internal carotid artery and jugular vein, spinal accessory = superficial to the carotid sheath but proceeding downward behind the posterior belly of the digastric muscle, and hypoglossal = same course as the spinal accessory. Remember also that the posterior belly of the digastric muscle is an excellent anatomic landmark, because behind it the following anatomic
entities may be found: the carotid arteries, the jugular vein, cranial nerves (X, XI, XII), and the sympathetic chain. Stenson's duct passes from the anterolateral edge of the gland, over the masseter muscle. At the anterior margin of the muscle, it turns medially to pierce the buccinator muscle and it enters the oral cavity at the level of the upper second molar tooth. An accessory gland is occasionally found along the course of the duct (Fig. 9). It follows a line drawn from the floor of the external auditory meatus to just above the commissure of the lips. These are important landmarks in evaluating facial lacerations with possible duct injury. There is no natural plane between the gland and the overlying skin. Surgical exposure requires raising the cheek flap in the subcutaneous plane just beneath the hair follicles. The gland is fixed by fibrous attachments to the external acoustic meatus, the mastoid process, and the fibrous sheath of the SCM. These must be released to mobilize the gland, facilitating exposure of the facial nerve. One of the fascial attachments is the stylomandibular ligament. It passes deep to the gland from the styloid process to the posterior border of the ascending ramus just above the angle, separating the parotid from the submandibular gland. Together with the mandibular ramus, it forms a tunnel through which a process of the gland can extend into the parapharyngeal space (Fig. 10). Occasionally, tumors can develop in the process, resulting in swelling in the facial and lateral pharyngeal area rather than externally. The facial nerve is intimately associated with the gland. It emerges from the skull through the stylomastoid foramen immediately posterior to the base of the styloid process and anterior to the attachment of the digastric muscle (Fig. 11). The main trunk of the facial nerve is always
Figure 10. Deep lobe parotid tumors may extend into the parapharyngeal space and present in the mouth.
SURGICAL ANATOMY OF THE NECK
Figure 11. The facial nerve has considerable variation in the distribution of peripheral branches. It has a constant location anterior to the attachment of the digastric muscle as it exits the stylomastoid foramen.
located in the triangle that is formed by the mastoid, the angle of the mandible, and the cartilaginous ear canal, with a location medial to the mastoid, almost at a point between the mandible and the cartilaginous ear canal. Before entering the gland, the nerve has three branches: (1) to the posterior auricular muscle; (2) to the posterior belly of the digastric muscle; and (3) to the stylohyoid muscle. The nerve enters the posterior surface of the gland about 1 em after exiting the skull. It is superficial to the external carotid artery and the posterior facial vein. The nerve branches into an upper temporofacial division that takes a vertical course and a lower cervicofacial division that is a transverse continuation of the main trunk. The point of branching is called the pes anserinus. From the pes, the nerve divides into five branches: temporal, zygomatic, buccal, mandibular, and cervical. The temporal and zygomatic branches share
the motor supply of the orbicularis oculi, and the temporal branch alone supplies the forehead musculature. The cervical branch supplies the platysma, and the remaining buccal and mandibular branches share the supply of the remaining facial muscles. The primary division is constant, but there is considerable variation in the origins, interrelations, and specific distribution of the peripheral branches (Fig. 11). The pattern of branching is particularly variable, and rami often communicate between branches, sometimes within the gland, but more often in front of its anterior border.5 The presence of these communicating rami explains the occurrence of unexpected mild paralysis following division of a branch. The facial nerve runs within the substance of the gland, but remember that within the gland the facial nerve is superficial, the veins are deeper, and the arterial branches are deepest. Traditionally, the path of the nerve has been used to separate the parotid into superficial and deep lobes, but there are no true facial planes separating the two. In 1956, two very important but very controversial papers appeared in the literature about the unilobar formation 21 and the bilobar formationS of the parotid gland. Dr. John E. Skandalakis (personal communication) notes that he has seen both types in the laboratory, but they were not very well defined or separated. Tumors generally develop superficial or deep to the plane of the nerve, thus the distinction of superficial and deep lobe tumors. Occasionally, a tumor will arise in the plane of the nerve, separating the branches. Parotidectomy requires precise identification of the facial nerve. The main trunk is constantly found between the base of the styloid process and the mastoid process. The tail of the parotid must be separated from the SCM muscle. Lateral traction of the muscle exposes the digastric muscle, which is followed to its insertion on the mastoid tip. The nerve lies between the insertion of the muscle and the styloid process (see Fig. 11). In difficult cases, the nerve can be found by removing the mastoid tip with an osteotome. This exposes the nerve in the descending portion of the facial canal as it exits through the stylomastoid foramen. If the tumor mass overlies the main nerve trunk, an optional approach would be to identify the posterior facial vein as it enters the gland. The marginal mandibular nerve can be seen crossing superficial to this vein, and can be followed to the main trunk. The external carotid artery enters the inferior surface of the gland and divides into the maxillary and superficial temporal arteries at the junction between the middle and upper third of the gland. The superficial temporal gives off the transverse facial artery to supply the face before continuing upward to emerge from the upper border of the gland. The maxillary artery passes forward and slightly upward behind the condylar neck in the part of the gland lying deep to it. The artery emerges from the gland and passes into the infratemporal fossa. The venous drainage of the area is variable, but the superficial temporal vein generally enters the superior surface and receives the internal maxillary vein to become the posterior facial vein. Within the gland, it divides into a posterior branch that joins the posterior auricular vein to form the external jugular vein and an anterior branch that emerges from
SURGICAL ANATOMY OF THE NECK
the gland to join the common facial vein. The facial nerve is superficial to the vessels, the artery is deep, and the veins lie between them. Knowledge of the lymphatics of the parotid is important in evaluating skin cancers of the head. Preauricular lymph nodes in the superficial fascia drain the temporal scalp, upper face, and anterior pinna. Lymph nodes within the parotid substance drain the gland, nasopharynx, palate, middle ear, and external auditory meatus. These lymphatics drain into the internal jugular and spinal accessory nodes. The greater auricular nerve emerges from the posterior border of the SCM muscle at Erb's point (Fig. 4). It crosses the midportion of the muscle approximately 6.5 cm beneath the external auditory meatus. 16 It travels parallel and superior to the external jugular vein to supply sensation to the ear and preauricular region. It passes on the surface of the parotid gland, and it can be preserved unless invaded by tumor by retracting it posteriorly. If the nerve must be sacrificed, it is preserved in saline for use as a possible nerve graft. Loss of the branches to the ear can cause disturbing numbness of the lobule, making it difficult to wear earrings, and sometimes causing frostbite in the winter. The auriculotemporal nerve is a branch of the mandibular division of the trigeminal nerve. It traverses the upper part of the parotid gland and emerges from the superior surface with the superficial temporal vessels. It carries sensory fibers from the trigeminal and secretory fibers from the glossopharyngeal nerve via the otic ganglion. Frey's syndrome is a localized sweating and flushing during the mastication of food. It is a common disorder that occurs in 35% to 60% of patients after parotidectomy with a facial nerve dissection?' 9 The syndrome usually will present several months after surgery and have varying degrees of severity. It may result from aberrant regeneration of nerve fibers from postganglionic secretomotor parasympathetic innervation to the parotid gland occurring through the severed axon sheaths of the postganglionic sympathetic fibers that supply the sweat glands of the skin. The majority of affected patients do not seek treatment.
(1) Knowledge of the enveloping fascial layers of the neck enables preservation of many vital structures during extirpation of metastatic cancer. (2) The submaxillary triangle contains the most intricate anatomy in the neck. The marginal mandibular nerve coursing over the facial vessels is the only important structure superficial to the digastric muscles. The lingual and hypoglossal nerves are found on the floor of the triangle and course under the mylohyoid muscle to enter the mouth. (3) Precise identification of the facial nerve is necessary to perform a parotidectomy. The tail of the parotid must be mobilized off the sternocleidomastoid muscle to expose the insertion of the digastric muscle on the mastoid process. The nerve is found just medial to this insertion.
References 1. Beahrs OH: Surgical anatomy and technique of radical neck dissection. Surg Clin North Am 57:663, 1977 2. Bocca E, Pignataro 0: A conservation technique in radical neck dissection. Ann Otol 76:975, 1967 3. Crile G: Excision of cancer of the head and neck. JAMA 47:1780,1906 4. Coller FA, Yglesias S: The relations of the spread of infection to fascial planes in the neck and thorax. Surgery 1:323,1937 5. Davis RA, Anson BJ, Budinger JM, Kurth LE: Surgical anatomy of the facial nerve and parotid gland based upon a study of 350 cervicofacial halves. Surg Gynecol Obstet 102:385, 1956 6. Dingman RO, Grabb WC: Surgical anatomy of the mandibular ramus of the facial nerve based on dissection of 100 facial halves. Plast Reconstr Surg 29:266,1962 7. Gordon AB, Fiddian RV: Frey's syndrome after parotid surgery. Am J Surg 132:54, 1976 8. Grodinsky M, Holyoke EA: The fasciae and fascial spaces of the head and neck and adjacent regions. American Journal of Anatomy 63:367,1938 9. Hays LL, Novack AJ, Worsham JC: The Frey syndrome: A simple, effective treatment. Otolaryngol Head Neck Surg 90:419,1982 10. Jesse RH, Ballantyne AJ, Larson D: Radical or modified neck dissection. A therapeutic dilemma. Am J Surg 136:516, 1978 11. Johns ME, Kaplan MJ. Surgical therapy of tumors of the salivary glands. In Thawley SE, Panje WR (eds): Comprehensive Management of Head and Neck Tumors. Philadelphia, WB Saunders, 1987, p 1104 12. Lindberg R: Distribution of cervical lymph node metastases from squamous cell carcinoma of the upper respiratory and digestive tracts. Cancer 29:1446,1972 13. Martin H, et al: Neck dissection. Cancer 4:441, 1951 14. McKenzie J: The parotid gland in relation to the facial nerve. J Anat 82:183, 1948 15. McKenzie J: The first arch syndrome. Dev Med Child NeuroI8:56, 1966 16. McKinney P, Katrana DJ: Prevention of injury to the great auricular nerve during rhytidectomy. Plast Reconstr Surg 66:675, 1980 17. Patey DH, Ranger I: Some points in the surgical anatomy of the parotid gland. Br J Surg 45:250, 1958 18. Rouviere H: Anatomy of the Human Lymphatic System. Ann Arbor, Edwards Brothers, 1938 19. Skandalakis JE, Gray SW, Rowe JS Jr: Surgical anatomy of the submandibular triangle. Am Surg 45:590,1979 20. Skandalakis JE, Gray SW, Rowe JS Jr: The neck. In Anatomical Complications in General Surgery. New York, McGraw-Hill, 1983, pp 3-17 21. Winsten J, Ward GE: The parotid gland: An anatomic study. Surgery 40:585, 1956
Address reprint requests to Grant W. Carlson, MD Winship Cancer Center Emory University 1327 Clifton Road, NE Atlanta, GA 30322