Functional Neck DissectionA

Description of Operative TechniqueBocca, MD; Oreste Pignataro, MD; Clarence T. Sasaki, MD

Ettore

\s=b\ The operative technique involved in functional neck dissection is described to clarify its stepwise execution. Recent interest in functional preservation demands therapeutic techniques that are oncologically reliable but not mutilating. The functional neck dissection seems to be a reasonable alternative to radical radiotherapy and a preferred alternative to traditional neck dissection in the control of regional metastasis when disease in the neck is either occult or still confined to mobile lymph nodes.

routine, radical removal of struc by nodal disease remained largely unchallenged forThetures uninvolved

(Arch Otolaryngol 106:524-527, 1980)

neck dissection, first described by Crile1 in 1906, is a destructive procedure designed to remove tumor-bearing lymph nodes of the neck. In an attempt to remove the lymphatics as completely as possi ble, traditional neck dissection in cluded removal of the submaxillary salivary gland, internal jugular vein, greater auricular and spinal accessory nerves, as well as digastric, stylohyoid, and sternomastoid muscles.

Radical widely'

for publication Oct 16, 1979. From the Otorhinolaryngology Clinic, Univerof Milan, Milan, Italy (Drs Bocca and Pignasity taro), and the Section of Otolaryngology, Department of Surgery, Yale University School of Medicine, New Haven, Conn (Dr Sasaki). Reprint requests to Department of Surgery, 333 Cedar St, New Haven, CT 06510 (Dr Sasa-

Accepted

ki).

despite the anatomic and func tional deformities it produced. In 1953, Pietrantoni,2 a strong advo cate of bilateral elective neck dissec tion, recommended sparing the spinal accessory nerves and at least one internal jugular vein. This break with surgical tradition was first limited to elective neck dissections, but was later extended to therapeutic dissections when lymph nodes were enlarged but still mobile. On the basis of the anatomic and surgical contributions of Suarez,1 Boc ca,4 in 1966, modified the traditional neck dissection, radically revising those concepts historically identified with the surgical treatment of region al metastasis. A staunch opponent of conservative nodal stripping, Bocca5 indicated the complete effectiveness of his surgical technique, which he described in the Semon Lecture to the Royal Society of Medicine in 1975. He called this technique the functional neck dissection, a procedure that made no concession to oncologie radicality and that was based on sound anatomic and surgical concepts. The anatomic basis for functional neck dissection has been described in great detail by others and therefore will not be repeated. The purpose ofyears,

clarify the operative technique concerning the procedure, which originated with Boc ca in Europe and which promises to become a preferred alternative to theclassical neck dissection or radical radiotherapy when regional metasta sis is either strongly suspected or con fined within palpable lymph nodes of the neck.OPERATIVE TECHNIQUEThe total operative time for a unilateral neck dissection varies from one to two hours. 1. In bilateral neck dissection, a superi orly based apron flap is preferred, whereas a hockey-stick skin incision may be used when neck dissection is unilateral. 2. By raising skin flaps that include the platysma muscle, generous exposure of the cervical structures is obtained (Fig 1). Care is taken to preserve the greater auricular and marginal mandibular nerves. The point at which the greater auricular nerve emerges from behind the sternomastoid muscle (Erb's point) is an important land mark (arrow in Fig 1) because it indicates the superior extent of the supraclavicular dissection to be accomplished later. The external jugular vein is temporarily pre served along its entire course, as is the superficial cervical fascia enveloping the sternomastoid muscle. 3. The external jugular vein is ligated and divided superiorly (Fig 2). The superfi cial cervical fascia is now cut along the posterior border of the sternomastoid mus-

this communication is to

Downloaded from www.archoto.com at Washington University - St Louis, on July 5, 2010

ele. By forward retraction on the cut edge of the fascia, the sternomastoid is "un wrapped." Minor bleeding from the muscle belly is controlled by electrocoagulation. The divided external jugular vein will now form the apex of the supraclavicular fossa dissection to which it remains attached. 4. Attention is now turned to the superior limit of the operative field. The superficial cervical fascia is cut along the lower border of the submaxillary fossa against the lateral surface of the submaxil lary gland, preserving the marginal man dibular nerve (Fig 3). By downward retrac tion on this fascia, nodal tissue may be freed from the submaxillary gland and lower pole of the parotid. 5. By upward retraction of the mandibu lar angle and posterior retraction of the sternomastoid muscle superiorly, fascia is stripped from the digastric and stylohyoid muscles, exposing the spinal accessory nerve as it crosses the lateral cervical space to enter the sternomastoid muscle (Fig 4). To free the accessory nerve, tissue overly-

ing it is incised longitudinally along its direction. Potential node-bearing tissue and fascia surrounding the nerve is metic ulously dissected from the nerve trunk and slipped under it. This dissection, best accomplished with a needle-tipped electrocautery, is carried medially to the levator scapulae muscle, which forms the deep ormedial extent of this dissection. Dissection with the electrocautery needle minimizes bleeding and facilitates identification of the accessory nerve. With the electrocau tery turned to a low setting, injury to the nerve has never occurred. The occipital artery, in close approximation to the acces sory nerve, should be avoided if possible. Inadvertent injury to this artery causes unnecessary bleeding that may obscure identification of the nerve. Anterior and medial to the accessory nerve, care should be taken to identify and avoid injuring the internal jugular vein at this level. 6. The superficial cervical fascia is now dissected from the posterior border of the sternomastoid muscle (Fig 5). Retracting

this muscle anteriorly will expose the direc tion of the accessory nerve as it enters the trapezius muscle, posteroinferiorly. Dissec tion of the supraclavicular fossa is carried superiorly only as far as Erb's point, to protect this portion of the accessorynerve.

7. The supraclavicular tissue, limited posteriorly by the trapezius muscle and inferiorly by the clavicle, is dissected medially up to the brachial plexus of nerves that rests on the prevertebral muscles. The phrenic nerve and thoracic duct are care fully preserved as the contents of the supraclavicular fossa, including the exter nal jugular vein, are delivered anteriorly under the belly of the sternomastoid mus cle (Fig 5). 8. Superiorly in the neck, meticulous dis section of potential node-bearing tissue is carefully accomplished from around the thyro-lingual-facial venous trunk (Fig 6, black arrow). Inspection of the space

medial to the sary to avoid

venous

trifurcation is

neces venous

missing disease. The

Fig 1 Skin flaps are raised deep to platysma muscle. Care must be taken to avoid injury to greater auricular (GA) and marginal mandibular (MM) nerves. External jugular vein (EJ) and superfi cial cervical fascia overlying sternomastoid muscle (SM) are temporarily preserved. Note position of Erb's point (arrowhead).

cervical fascia is cut along posterior border of sternomastoid muscle and, with No. 15 blade, is dissected anteriorly as muscle is "unwrapped." External jugular vein is divided superiorly and left attached to contents of supraclavicular fossa.

Fig 2.Superficial

Downloaded from www.archoto.com at Washington University - St Louis, on July 5, 2010

trifurcation may be resected if nodes medial to this venous trunk are suspected to contain metastatic tumor. 9. The specimen, now freed superiorly, posteriorly, and inferiorly, remains at tached to the internal jugular vein and carotid artery (Fig 6). Final dissection from these large vessels is easily accom plished, resulting in complete removal of

all

aspect of the neck (Fig 7).

lymph-bearing tissues from the lateralCOMMENT

Otorhinolaryngology Clinic of Milan, Italy, in 1975. Of 403 patients with laryngeal cancer treated by tradi

According Bocca,5 the effective ness of functional neck dissection is favorably compared to traditional neck dissection in a report from theto

tional neck dissection, 70% of those with NO disease survived five years, whereas 44% of those with Nl-2 dis ease (mobile nodes) survived five years. On the other hand, of 367

Fig 3.Superficial cervical fascia is dissected from medial sur face of sternomastoid muscle. This fascia is now cut along lower border of submaxillary fossa against lateral surface of submaxil lary gland, protecting marginal mandibular nerve. Potential lymph-bearing tissue is dissected from submaxillary salivary gland (SG) and lower pole of parotid gland (PG).

nerve is identified by strong upward retraction on mandible and posterosuperior retraction of sterno mastoid muscle. Tissue overlying nerve is incised along its direction. As nerve is freed, surrounding fascia and soft tissue is passed anteriorly beneath nerve trunk. A good deal of importance is placed on meticulous dissection around this nerve, such that the deep margin of this compartment is cleaned to the levator scapulae muscle. Occipital artery, passing in close proximity to accessory nerve, should be avoided. Care must be taken to identify internal jugular vein, located anterior to accessory

Fig 4.Spinal accessory

nerve.

Fig 5.Superficial cervical fascia is now dissected from posterior border of sternomastoid muscle. Contents of supraclavicular fossa are dissected from trapezius muscle posteriorly, across clavicle inferiorly, and deep to, but not including, brachial plexus (BP) overlying prevertebral muscles. This dissected block of tissue, marked superiorly by Erb's point, is delivered anteriorly deep to sternomastoid muscle. As this dissection proceeds anteriorly, care must be taken to preserve the phrenic nerve andthoracic duct low in the neck.

Downloaded from www.archoto.com at Washington University - St Louis, on July 5, 2010

Fig 6.Careful dissection of fascia from internal jugular vein (IJ) and carotid artery (CA) is accomplished, paying specific attention to thyro-lingual-facial venous trifurcation high in neck. This trifurcation is either divided and included in neck specimen, or space behind it is carefully inspected for possible nodal disease(black arrow).

Fig 7.Completed neck dissection should now have preserved marginal mandibular (MM) and greater auricular (GA) nerves, internal jugular vein (IJ), carotid artery (CA), vagus and sympa thetic nerves, as well as phrenic nerve and brachial plexus (BP). Sternomastoid (SM) and omohyoid (OH) muscles remain intact.

patients treated by functional neck dissection, 89% of patients with NO disease and 48% of patients with Nl-2

tal

disease survived five years. No pa tient received adjuvant radiotherapy. Such a favorable comparison would indicate, therefore, that functional neck dissection fulfilled the require ments of oncologie safety while avoid ing unnecessary mutilation. It should be apparent that function al neck dissection has nothing in com mon with the mere stripping of lymph nodes. Rather, it is a complete dissec tion of the lateral cervical space, ana tomically confined by a fasciai enve lope, and itself containing the major cervical lymphatics.5 The preservation of major nerves, vessels, and muscle does not appear to compromise onco logie safety. Functional preservation of the neck presents undeniable

anesthesia. 2. Bilateral dissection may be per formed simultaneously without dan ger of abrupt venous congestion intra-

pain, limitations of neck and limb motion, and widespread cutaneous

cranially. 3. It provides a reasonable alterna tive to radical radiotherapy of the neck, when the preferred treatment of the primary tumor is surgical. Thus, the untoward biologic consequences of radiation are avoided entirely, with out resorting to the mutilation of tra

contraindication to functional neck dissection. However, previous radia tion to the neck is not considered a contraindication to this procedure. It is hoped that the essential points of this technique have been adequate ly described at a time when increasing interest in functional preservation is both demanded by the patient and required by the physician.This study was supported by a grant to Dr Sasaki from the International Union Against Cancer.

advantages:

1. It avoids unjustified conse quences of the traditional neck dissec

ditional neck dissection. 4. When the preferred treatment of the primary tumor requires combined surgery and radiation, functional neck dissection may alter the decision for neck irradiation in patients with NO disease. Indeed, it may alter the man ner in which adjuvant radiation is delivered in patients with Nl-2 disease.

References1. Crile G: Excision of cancer of the head and neck. JAMA 47:1780-1786, 1906. 2. Pietrantoni L: Il problema chirurgico delle metastasi linfoghiandolari del cancro della laringe. Arch Ital Otol, suppl 14, 1953. 3. Suarez O: El problema de las metastasis linfaticas y alejadas del cancer de laringe e hipofaringe. Rev Otorrinolaryngol Santiago 23:83-99, 1963. 4. Bocca E: Supraglottic laryngectomy and functional neck dissection. J Laryngol 80:831-838, 1966. 5. Bocca E: Critical analysis of the techniques and value of neck dissection. Arch Ital Otol Rinol Laryngol 4:151-158, 1976.

tion, including dropped shoulder,

skel-

opinion that N3 disease (fixed nodes) represents an absoluteour

It is

Downloaded from www.archoto.com at Washington University - St Louis, on July 5, 2010