Introduction to surgery of the neck

1. Surgical Anatomy and Oncological Discussion of
the Neck
Dr Shaurya Pratap Singh

2. Surface Anatomy of the Neck

3. Surface Anatomy of the Neck

5. Approximate Locations of Neck Structures
 A. Vessels
 1. Common carotid artery: on line from upper border of sternal end of clavicle to point midway between mastoid
process and angle of mandible
 2. Subclavian artery: indicated by arch with medial end at sternoclavicular joint and lateral end at middle of clavicle
 3. Carotid sinus: pressure near carotid bifurcation can stimulate baroreceptors to elicit vagal reflex that will slow
heartbeat and lower blood pressure, causing fainting
 4. Internal jugular vein: follows same line as internal/common carotid artery
 B. Nerves
 1. Vagus: same line as internal jugular vein and internal/common carotid artery
 2. Accessory: passes under SCM 3.75 cm (1.5 in) below tip of mastoid; emerges from posterior border of that
muscle at junction of upper and middle 2/3; passes obliquely downward and backward across posterior triangle to
pass under anterior border of trapezius 5 cm (2 in) above clavicle.
 3. Phrenic: begins at level of middle of lamina of thyroid cartilage; its caudal course is indicated by line down
middle of SCM, parallel to direction of muscle.
 C. Thyroid gland
 Upper pole contacts lower portion of lamina of thyroid cartilage, inferolateral to prominence; lower pole may reach
level of 5th or 6th tracheal ring; isthmus crosses tracheal rings 2–3.

6. Cervical Triangles and Fascia
 Anterior triangle
 1. Boundaries
 a. Midline
 b. SCM muscle
 c. Body of mandible
 2. Subdivisions
 a. Submandibular triangle: body of mandible, anterior and posterior bellies of digastric
muscle
 b. Submental triangle: anterior belly of digastric muscle, body of hyoid bone, midline
 c. Carotid triangle: posterior belly of digastric muscle, superior belly of omohyoid
muscle, SCM muscle
 d. Muscular triangle: SCM muscle, superior belly of omohyoid muscle, midline

7.  Posterior triangle
 1. Boundaries
 a. SCM muscle
 b. Trapezius muscle
 c. Clavicle
 2. Subdivisions
 a. Occipital triangle: SCM muscle, trapezius muscle, inferior belly of omohyoid
 b. Omoclavicular (subclavian) triangle: SCM muscle, inferior belly of omohyoid muscle,
clavicle.
Cervical Triangles and Fascia

8. Cervical Triangles and Fascia

9. Cervical Triangles and Fascia

10. Skin and Superficial Fascia
 Skin of neck: fibres of dermis (so-called “Langer’s lines”) run in transverse direction; incisions
made accordingly.
 Superficial fascia of neck: loose areolar connective tissue containing platysma muscle, superficial
blood vessels, cutaneous nerves, and superficial lymph nodes.
 1. Platysma muscle
 a. Origin: investing fascia covering pectoralis major and deltoid muscles
 b. Insertion: inferior border of mandible and skin of lower face, decussating with facial muscles
 c. Action: draws corners of mouth down; aids in depression of mandible
 d. Innervation: cervical branch of facial nerve (cranial nerve [CN] VII); emerges from parotid
gland near angle of mandible
 2. Superficial vessels and cutaneous nerves found primarily beneath platysma

11.  A. Superficial layer of deep cervical fascia
 1. Completely encircles neck
 a. Covers anterior and posterior triangles
 b. Splits to enclose SCM and trapezius muscles
 2. Attachments
 a. Posteriorly: external occipital protuberance, ligamentum nuchae, spine of C7
 b. Superiorly: superior nuchal line, mastoid process, mandible; invests parotid
and submandibular glands
 c. Inferiorly: clavicle, manubrium of sternum, acromion, and spine of scapula
 B. Infrahyoid fascia
 1. Investing fascia of infrahyoid muscles (omohyoid, sternohyoid, sternothyroid,
thyrohyoid)
 2. Consists of 2 layers
 a. Superficial encloses omohyoid and sternohyoid muscles
 b. Deep invests sternothyroid and thyrohyoid muscles
Deep Cervical Fascia

12.  C. Visceral fascia
 1. Encloses viscera of neck: larynx, trachea, thyroid, pharynx, and esophagus
 2. 2 subdivisions
 a. Pretracheal fascia
 i. Covers larynx and trachea; splits to enclose thyroid gland (forming false or
surgical capsule)
 ii. Attached superiorly to hyoid bone and thyroid cartilage; posterolaterally
continuous as buccopharyngeal fascia; inferiorly enters thorax to join fascia of
aorta and pericardium
 iii. Suspensory ligaments of thyroid gland: thickenings run from upper inner part
of thyroid gland to cricoid cartilage, anchoring gland to larynx; must be cut
before thyroid gland can be properly mobilized
 b. Buccopharyngeal fascia
 i. Covers buccinator muscle and posterior surface of pharynx and esophagus
 ii. Attached superiorly to pharyngeal tubercle and medial pterygoid plates
Deep Cervical Fascia

13.  D. Prevertebral fascia
 1. Forms tubular investment of vertebral column and its muscles; covers prevertebral
muscles and forms floor of posterior triangle; thicker than visceral fascia
 2. Attachments
 a. Laterally: transverse processes of cervical vertebrae
 b. Superiorly: occipital bone near jugular foramen, superior nuchal line, and mastoid
process
 c. Inferiorly: continues into mediastinum; forms
 2 structures
 Suprapleural membrane (Sibson’s fascia): scalene muscle fascia covering cervical pleura.
 Axillary sheath: scalene fascia covering axillary vessels and brachial plexus as they pass
through interscalene triangle
 E. Carotid sheath
 1. Adjacent deep fascial layers blend to form investment of carotid arteries (internal and
common) medially, internal jugular vein laterally, and vagus nerve between
 2. Adherent to visceral fascia on thyroid and superficial layer of deep cervical fascia under
SCM
 3 Attached superiorly to margins of jugular foramen and carotid canal; continues
inferiorly into thorax.
Deep Cervical Fascia

14. Deep Cervical Fascia

15. Deep Cervical Fascia

16. Fascial Spaces
 A. Retropharyngeal space
 1. Between buccopharyngeal and prevertebral fascia
 2. Extends from skull into mediastinum; major pathway for infection from neck into thorax
 a. Alar fascia: thin layer of fascia subdivides this space; attached in midline to buccopharyngeal
fascia; laterally, joins carotid sheath
 b. Retropharyngeal abscess can cause dysphagia, dysarthria, and mediastinitis
 B. Suprasternal space (of Burns)
 1. Between layers of superficial layer of deep cervical fascia, which splits at jugular notch to
attach to posterior and anterior sides of manubrium
 2. Contains jugular venous arch
 C. Pretracheal space
 1. Potential space in front of trachea and behind infrahyoid muscles and pretracheal fascia
 2. Limited above by attachment of pretracheal fascia to thyroid cartilage, but continues into
mediastinum to level of pericardium
 D. Parapharyngeal (lateral pharyngeal) space
 1. Lateral to pharynx
 2. Limited laterally by connective tissue capsule of parotid gland and pterygoid muscles,
posteriorly by prevertebral fascia, superiorly extends to skull base, and inferiorly continues with
connective tissue layer of carotid triangle.

17. Superficial Veins
 A. Location: within superficial fascia covered by platysma muscle
 B. Major superficial veins
 1. External jugular vein
 a. Formed by union of posterior division of the retromandibular vein with posterior auricular
(which can unite with the occipital vein)
 b. Descends vertically beneath platysma.
 c. Lies anterior to and roughly parallels great auricular nerve; obliquely crossing SCM muscle
 d. Pierces deep cervical fascia in posterior triangle and drains into subclavian vein; venous
valve located at termination
 e. Near termination, receives anterior jugular, transverse cervical, and suprascapular veins
 2. Anterior jugular vein
 a. Begins as union of small cutaneous veins in submental triangle; may receive connections
with external jugular or facial veins
 b. Descends near midline, parallel with its opposite partner; may be unilateral or absent
 c. Pierces superficial layer of deep cervical fascia above jugular notch of manubrium
 d. Jugular venous arch may unite paired anterior jugular veins across midline within
suprasternal space
 e. Each vein passes deep to SCM muscle to empty into external jugular

18.  3 Common facial (facial) vein
 a. Union of facial vein with anterior division of retromandibular vein; often referred to as facial
vein
 b. Pierces deep fascia to drain to internal jugular vein within upper part of carotid triangle
 4. Communicating vein (of Kocher)
 a. Frequent branch of common facial that descends along anterior border of SCM muscle
 b. Drains into anterior jugular vein
 C. Other superficial veins
 1. Posterior auricular vein
 a. Originates as small vein behind ear
 b. Joins posterior division of retromandibular to form external jugular vein
 2. Transverse cervical vein
 a. Drains trapezius muscle and posterior triangle region
 b. May unite with suprascapular before draining into external jugular vein
 3 Suprascapular vein
 a. Drains posterior shoulder region
 b. Drains to external jugular vein.
Superficial Veins

20. Cutaneous Nerves
 A. Posterior rami
 1. Greater occipital nerve (posterior ramus of C2)
 a. Passes below obliquus capitis inferior to penetrate semispinalis capitis and reach skin
 b. Distributes to skin on back of head up to vertex
 2. Occipitalis tertius (posterior ramus of C3): to skin of upper posterior neck
 3 Cutaneous branches of posterior rami of C4–C8: posterior neck and upper back laterally to
rib angles approximately

 B. Anterior rami (cervical plexus, C1–C4)
 1. Cervical plexus is represented by multiple looping connections between adjacent anterior
rami

21.  2. Cutaneous branches of cervical plexus
 a. Segmental distribution
 i. C1 has no cutaneous sensory distribution
 ii. C2: borders on sensory area of trigeminal nerve (CN V) and is limited mainly to cutaneous area behind
pinna of ear up to vertex of head
 iii. C3: passes cranially up to margin of mandible; extends over entire anterior cervical triangle and spreads
out laterally beyond SCM muscle area into posterior cervical triangle
 iv. C4: supplies root of neck and cutaneous area of thoracic wall to level of 1st intercostal space (borders on
distribution of anterior ramus of T1)
 b. Specific cutaneous nerves of cervical plexus:
 4 cutaneous branches emerge at posterior margin of SCM muscle (near its midpoint)
1. Lesser occipital nerve (C2): hooks around spinal accessory nerve, ascends along posterior border of SCM
muscle, and ends behind ear
2. Great auricular nerve (C2–C3): exits from under middle of posterior border of SCM muscle; branches pass to
skin of ear and adjacent areas
3. Transverse cervical nerve (C2–C3): exits below great auricular nerve, crosses SCM muscle transversely to
reach anterior triangle (crossing under external jugular vein), and supply skin between sternum and chin
4. Supraclavicular nerves: (C3–C4): exit from posterior middle border of SCM muscle and divides into 3 terminal
branches
 a) Medial: innervates skin as far as 2nd intercostal space and sternoclavicular joint
 b) Intermediate (middle): descends over middle 1/3 of clavicle, may pierce bone resulting in persistent
neuralgia if involved in callus following bone fracture
 c) Lateral: distributed to skin over point of shoulder and acromioclavicular joint.
Cutaneous Nerves

22. Cutaneous Nerves

23. Cutaneous Nerves

24. Anterior Triangle of the Neck
 Boundaries:
 A. Medially: midline
 B. Posterolaterally: anterior border of SCM muscle
 C. Superiorly: inferior border of mandible
 D. Roof: skin, superficial fascia, platysma muscle II.

25.  Subdivisions
 A. Carotid triangle
 1. Boundaries: posterior belly of digastric, superior belly of omohyoid, and anterior border of SCM muscle
 2. Floor: thyrohyoid, lowest portion of hyoglossus, and middle and inferior pharyngeal constrictor muscles
 3 Contents: bifurcation of common carotid artery; origins of external carotid artery and its 1st 5 branches;
hypoglossal and superior laryngeal nerves; superior root of ansa cervicalis
 a. Carotid sinus
 b. Carotid body
 c. Branches of external carotid artery within carotid triangle
 i. Superior thyroid artery
 ii. Lingual artery
 iii. Facial artery
 iv. Ascending pharyngeal artery
 v. Occipital artery
 d. Hypoglossal nerve (CN XII)
 i. Swings forward below lower border of posterior belly of digastric muscle.
 ii. Crossed by occipital artery and its SCM branch
 iii. Gives off superior root of ansa cervicalis (C1–C2 fibers)
 iv. Lies on hyoglossus muscle; passes forward into genioglossus muscle
Anterior Triangle of the Neck

26.  B. Muscular triangle
 1. Boundaries: superior belly of omohyoid muscle, anterior border of SCM muscle,
midline
 2. Contents: sternohyoid, sternothyroid, and thyrohyoid muscles; thyroid and parathyroid
glands; larynx; and trachea
 C. Submandibular triangle
 1. Boundaries: mandible and both bellies of digastric muscle
 2. Floor: mylohyoid muscle
 3 Contents: superficial portion of submandibular gland, facial vessels (vein crosses
superficial to gland, artery lies deep), mylohyoid vessels and nerve
 D. Submental triangle
 1. Boundaries: body of hyoid bone, anterior belly of digastric muscle, and midline
 2. Floor: mylohyoid muscle
 3 Contents: submental lymph nodes, submental branch of facial artery, and small
tributaries of anterior jugular vein.
Anterior Triangle of the Neck

33. Contents of Carotid Sheath
 A. Carotid arteries
 1. Common carotid
 a. Right: from brachiocephalic trunk
 b. Left: arises as second branch of aortic arch
 c. Both: course superiorly in carotid sheath with internal jugular vein laterally and vagus
nerve posterolaterally
 d. 2 terminal branches at superior border of thyroid cartilage: internal and external
carotid arteries
 e. Carotid body
 i. Small, flattened, ovoid nodule of specialized cells (0.5 cm) in outer connective tissue of
bifurcation of common carotid artery
 ii. Functions as chemoreceptor that monitors oxygen content of blood before it reaches
brain, such that a decrease in partial pressure of oxygen, which can occur at high altitudes
or in pulmonary disease, activates aortic and carotid chemoreceptors, increasing alveolar
ventilation; also sensitive to changes in blood acidity (relative amount of carbon dioxide)
 iii. Innervated by carotid sinus nerve (Hering’s nerve) of glossopharyngeal (CN IX), vagus
(CN X), and sympathetics

34.  2. Internal carotid artery
 a. Continues in carotid sheath to enter carotid canal in base of skull
 b. No branches in neck; supplies brain and orbit;
 c. Carotid sinus
 i. Slight dilation of terminal portion of common carotid and proximal part of internal carotid
artery
 ii. Functions as baroreceptor important in regulating arterial blood pressure
 iii. Innervated mainly by carotid sinus nerve from glossopharyngeal (CN IX); also supplied by
vagus (CN X) and sympathetic fibres
 3. External carotid artery
 a. Leaves carotid sheath by passing anterosuperiorly within carotid triangle
 b. 8 branches: 5 below posterior belly of digastric within carotid triangle, 3 above
 i. Superior thyroid artery: 1st branch; passes anteromedially to supply infrahyoid muscles,
thyroid gland, larynx, and laryngopharynx; gives off superior laryngeal artery that passes
through thyrohyoid membrane with internal branch of superior laryngeal nerve
 ii. Ascending pharyngeal artery: often 2nd branch; arises from medial surface to pass
superiorly to supply oro- and nasopharynx, prevertebral muscles, palatine branch to soft palate
 iii. Lingual artery: 2nd anteromedially directed branch; passes above greater horn of hyoid to
supply tongue, suprahyoid region, sublingual gland, and palatine tonsils
Contents of Carotid Sheath

35.  iv. Facial artery: 3rd anteromedial branch; passes deep to posterior belly of digastric and
stylohyoid muscles and superficial portion of submandibular gland to reach mandibular
margin and enter face anterior to masseter insertion; supplies submandibular gland and
face up to orbit
 v. Occipital artery: arises posteriorly near lower border of posterior belly of digastric
muscle, crosses hypoglossal nerve superiorly; passes posterosuperiorly roughly medial to
posterior belly of digastric to eventually distribute on head posteriorly; supplies SCM
muscle, meningeal branches, and scalp posteriorly
 vi. Posterior auricular artery: posteriorly directed branch arising between posterior belly of
digastric and stylohyoid muscles; ends in occipital and auricular branches; branches to
parotid gland; enters stylomastoid foramen to medial wall of middle ear, mastoid air cells,
stapedius muscle, and middle ear bones
 vii. Maxillary artery: anteromedially directed terminal branch; supplies muscles of
mastication, meninges, midface including upper teeth, nasal cavity, and hard and soft
palates
 viii. Superficial temporal artery: superiorly directed terminal branch; supplies scalp
laterally
Contents of Carotid Sheath

36.  B. Internal jugular vein
 1. Origin: in jugular fossa, as continuation of sigmoid sinus
 2. Course: in carotid sheath, first with internal and then common carotid artery
 3 Termination: joins subclavian vein just lateral to sternoclavicular joint to form
brachiocephalic vein
 a. Superior bulb: dilation at its origin
 b. Inferior bulb: dilation 1 in above termination, below pair of valves
 4. Tributaries (variable)
 a. At origin: inferior petrosal sinus and a meningeal vein
 b. Pharyngeal plexus, near angle of jaw
 c. Common facial (formed from anterior division of retromandibular and facial vein)
enters at level of hyoid bone
 d. Lingual, from tongue, may enter with or just below common facial, drains tongue and
sublingual area
 e. Superior thyroid, from upper thyroid gland, enters with or just below common facial
vein
 f. Middle thyroid vein, from the lateral portion of gland.
Contents of Carotid Sheath

37.  C. Vagus nerve (CN X) in neck
 1. Exits skull at jugular foramen to enter carotid sheath and lie between and behind internal
jugular vein and internal and common carotid arteries
 2. Gives off superior laryngeal nerve and superior cardiac branch below base of skull
 3. Gives multiple small branches to pharynx
 4. Gives off inferior cardiac branch in root of neck
 5. Passes anterior to right subclavian artery or lateral to left common carotid to enter thorax D.
 D. Other contents of carotid sheath
 1. Superior laryngeal nerve (from CN X): passes medial to internal carotid artery to leave
sheath and pass to larynx
 2. Accessory nerve (CN XI): leaves sheath near base of skull to pass laterally toward SCM
muscle
 3. Glossopharyngeal nerve (CN IX): leaves sheath to pass inferoanteriorly onto posterior
wall of pharynx
 4. Hypoglossal nerve (CN XII): passes inferoanteriorly between internal jugular vein and
internal carotid artery to reach tongue
 5. Deep cervical lymph nodes: lie along internal jugular vein and between it and common
carotid artery; not always easily visible, being small and scattered, but are important in
carcinoma of mouth, larynx, or other head and neck structures.
Contents of Carotid Sheath

39. Key points of history and examination

40. Lymphatic Spread
 The cervical lymphatic nodal basins contain 50 to 70 lymph nodes per side and are
divided into seven levels.
 The lymph nodes of the neck are somewhat arbitrarily divided into groups, which are then
described according to the position in which they lie.
 • Submental and submandibular nodes drain the floor of the mouth and the tongue. These
nodes are described as level I cervical nodes.
 • Deep cervical nodes lie deep to the sternocleidomastoid muscle and the deep cervical fascia.
They lie both outside and within the carotid sheath, in contact with the internal jugular vein.
They drain the tonsil, the pharynx, the larynx, the trachea and the thyroid gland.
Inflammation within them is therefore common with upper respiratory infections, and
carcinoma of the pharynx, larynx or thyroid may present with an enlarged metastatic node in
this group. They are subdivided into level II, III and IV cervical nodes, representing the upper,
middle and lower nodes of this group.
 • Preauricular, mastoid and occipital nodes are superficial nodes that drain the skin and
superficial tissue of the face and scalp.
 • The posterior triangle nodes are deep to the investing fascia. They are classified as level V
nodes.
 • Supraclavicular nodes are continuous with the superior mediastinal nodes and with the
axillary nodes. Metastatic involvement is seen in breast, bronchial and upper gastrointestinal
cancer. Supraclavicular nodes are also classified as level V cervical nodes.
 • Anterior compartment nodes surround the midline visceral structures and include the
retropharyngeal, paratracheal, prelaryngeal and pretracheal nodes. They are classified as the
level VI group.

41.  Level I is subdivided:
 • Level IA is bounded by the anterior belly of the digastric muscle, hyoid bone,
and midline.
 • Level IB is bounded by the anterior and posterior bellies of the digastric muscle
and the inferior border of the mandible. Level IB contains the submandibular gland.

42.  Level II is bounded superiorly by the skull base, anteriorly by the stylohyoid muscle, inferiorly
by a horizontal plane extending posteriorly from the hyoid bone, and posteriorly by the
posterior edge of the sternocleidomastoid muscle. Level II is further subdivided:
 • Level IIA is anterior to the spinal accessory nerve.
 • Level IIB, or the so-called submuscular triangle, is posterior to the nerve.
 Level III begins at the inferior edge of level II and is bounded by the laryngeal strap muscles
anteriorly, by the posterior border of the sternocleidomastoid muscle posteriorly, and by a
horizontal plane extending posteriorly from the inferior border of the cricoid cartilage.
 Level IV begins at the inferior border of level III and is bounded anteriorly by the strap
muscles, posteriorly by the posterior edge of the sternocleidomastoid muscle, and inferiorly by
the clavicle.
 Level V is posterior to the posterior edge of the sternocleidomastoid muscle, anterior to the
trapezius muscle, superior to the clavicle, and inferior to the base of the skull.
 Level VI is bounded by the hyoid bone superiorly, the common carotid arteries laterally, and
the sternum inferiorly. Although level VI is large in area, the few lymph nodes that it contains
are mostly in the paratracheal regions near the thyroid gland.
 Level VII (superior mediastinum) lies between the common carotid arteries and is superior to
the aortic arch and inferior to the upper border of the sternum.

46.  Lymphatic drainage usually occurs in a superior to inferior
direction and follows predictable patterns based on the
primary site. Primary tumors of the lip and oral cavity
generally metastasize to nodes in levels I, II, and III, although
skip metastases may occur in lower levels. The upper lip
primarily metastasizes ipsilaterally, whereas the lower lip has
ipsilateral and contralateral drainage.
 Tumors in the oropharynx, hypopharynx, and larynx usually
metastasize to levels II, III, and IV. Tumors of the nasopharynx
spread to the retropharyngeal and parapharyngeal lymph
nodes as well as to levels II through V. Other sites that
metastasize to the retropharyngeal lymph nodes are the soft
palate, posterior and lateral oropharynx, and hypopharynx.
Tumors of the subglottis, thyroid, hypopharynx, and cervical
esophagus spread to levels VI and VII. In addition to the lower
lip, the supraglottis, base of the tongue, and soft palate have
a high incidence of bilateral metastases.

47. Surgical management of neck
 Retropharyngeal abscess
 The retropharyngeal space lies between the pharynx and the
posterior layer of the deep fascia, and extends from the base of
the skull to the level of the tracheal bifurcation in the posterior
mediastinum. In the adult, retropharyngeal abscesses are usually
tuberculous, secondary to cervical spine involvement.
 In contrast to pyogenic retropharyngeal abscesses in the child,
which are drained into the oropharynx, the tuberculous pus should
be drained to the exterior. A horizontal incision is made, one finger
breadth below the angle of the jaw. The tail of the parotid gland is
dissected from the sternocleidomastoid, which is then retracted.
The carotid sheath is retracted posteriorly. The superior constrictor
is then identified and, by passing a finger lateral and posterior to
the pharynx, the retropharyngeal space can be entered. Locules
are broken down, the pus evacuated and a deep drain left in the
cavity.

49.  Parapharyngeal abscess
 The parapharyngeal space lies lateral to the pharynx. It is bounded laterally by the lateral
pterygoid muscle and the parotid gland. It extends from the base of the skull to the level
of the hyoid bone, where it is limited by the fascia over the submandibular gland. The
carotid sheath lies posteriorly. An abscess in this space may be associated with a tonsillar
infection and a quinsy, or with an infected lower third molar tooth. The primary
pathology should be addressed first. However, drainage of pus will probably still be
inadequate, and direct drainage of the parapharyngeal space may still be required. A
horizontal incision is made over the anterior border of sternocleidomastoid, two finger
breadths below the jaw. The sternocleidomastoid muscle is retracted posteriorly and the
deep cervical fascia incised to enter the abscess cavity. This abscess is deep and often
multiloculated, and is best explored with blunt finger dissection. It will also require a
drain left in situ after initial drainage.
 Drainage of purulent lymphadenitis
 Purulent lymphadenitis can occur secondary to a tonsillitis or other upper respiratory tract
infection, and is encountered most frequently in infants. The upper deep cervical chain is
the most commonly involved, but by the time it is apparent that there is pus and that the
infection will not resolve with antibiotics, there is simply a collection of pus laterally in
the neck, which must be drained. A formal dissection with identification of the
sternocleidomastoid and incision of the deep fascia to enter the deeper planes is
seldom necessary. A small transverse incision over the most prominent part of the
swelling, which is then deepened until pus drains, is normally sufficient. This incision will
leave a satisfactory scar but will provide inadequate continuing drainage unless a drain is
placed into the depth of the abscess and sutured to the skin.

50.  Diagnostic lymph node biopsy
 The differential diagnosis of an enlarged cervical lymph node includes inflammation,
lymphoma and metastatic malignancy. Up to one in five patients with a carcinoma of the
nasopharynx, oral cavity, oropharynx, larynx or hypopharynx presents with a nodal
metastasis. Such nodes should be excised en bloc with the other drainage nodes and
the primary malignancy to maximise the chance of cure. Nodal biopsy in isolation for
diagnosis should be avoided as there is evidence that this increases morbidity, and
possibly decreases long-term survival, in patients with squamous carcinoma. A general
surgeon who sees a patient with an isolated neck node, particularly in the submandibular
area or in the deep cervical chains, should seek an ENT opinion prior to biopsy, so that
malignancy within the drainage area can be excluded. The position of the enlarged node
is a guide as to the site of the primary pathology. Thyroid cancer can also present with a
cervical node metastasis, but in this cancer an initial excision of the node does not so
adversely affect prognosis.
 Malignant supraclavicular nodes are usually associated with advanced malignancies,
often from a primary in the breast, chest or abdomen, which is no longer surgically
curable. Isolated excision biopsy is therefore oncologically harmless. Fine-needle
aspiration may be sufficient to confirm metastatic cancer cells, but often cannot
differentiate between inflammatory and lymphomatous changes, for which a node
biopsy is necessary. The histologist must be able to study the architecture of the
gland and, ideally a whole node is excised, with the dissection on the capsule of the
node. If this is not possible due to the proximity of vital structures or when nodes are
matted together, a generous wedge excision is a safe compromise.

51.  Occipital and posterior triangle nodes are relatively superficial with no large vessels
nearby. Local anaesthesia is therefore suitable. The operation, however, should not be
underestimated or undertaken for insignificant nodes. The surgeon must be aware of
the surface markings of the accessory nerve when removing level V nodes, as the nerve
crosses the posterior triangle at the level of the deep fascia. The nodes lie in close
proximity to the nerve, which is thus extremely vulnerable to injury either from surgical
division or diathermy damage. Accessory nerve injury results in significant shoulder
dysfunction.
 Deep cervical nodes are deep to sternocleidomastoid and general anaesthesia and a
protected airway are recommended. A transverse incision through skin and platysma,
followed by posterior retraction of the sternocleidomastoid muscle after incision of the
deep cervical fascia along its anterior border, will bring the surgeon into the correct plane.
Care must be taken not to damage the internal jugular vein; its anterior tributaries, such
as facial and thyroid veins, may have to be ligated and divided.
 Supraclavicular nodes are often deceptive and found at operation to be deeper than
initially suspected. They may merely be the only accessible part of a huge mass of
matted mediastinal nodes, which are compressing the trachea and distorting the
anatomy of the great vessels at the root of the neck. The surgeon should dissect with
caution under optimum surgical and anaesthetic conditions. Tracheal compression in the
superior mediastinum can make a general anaesthetic hazardous, but this is also a
hazardous area for a surgeon to operate under local anaesthesia.

52. Advantages and disadvantages larynx and pharynx examination
techniques

53. The TNM staging system

54. Clinical and pathologic T category for oral cavity cancer

55. Clinical and pathologic T category for HPV-associated (p16-positive) oropharyngeal cancer

56. Clinical and pathologic T category for non–HPV-associated (p16-negative) oropharyngeal
cancer

57. Tumour–node–metastasis (TNM) classification of laryngeal carcinoma.

58. Classification of Different Types of Neck Dissection with Clinical Indication

60. Clinical N category for oral cavity, larynx, and hypopharynx cancer and Clinical N category for non–HPV-
associated (p16-negative) oropharyngeal cancer

62. Skin incisions for various types of neck dissections

63.  Comprehensive Modified Neck Dissection: Type 1
 Anaesthesia: General endotracheal anaesthesia with muscle relaxation is essential for performing
a neck dissection. The patient is usually placed in a supine position with the head elevated to
30 degrees. The neck is hyperextended and rotated to the opposite side.
 Incision
 For MRND type l a single trifurcate neck incision is the most frequently employed incision.
 Procedure
 The dissection begins with elevation of the posterior skin flap. Skin is incised with the scalpel
and then the remainder of the procedure is carried out using electrocautery. The skin incision
is deepened through the subcutaneous tissue and then through the platysma muscle. The
posterior flap is then raised in the subplatysmal plane by applying traction to the flap with skin
hooks and countertraction of the deeper soft tissues. The flap is elevated up to the anterior
border of the trapezius muscle. During this elevation. care is taken not to enter the posterior
triangle fat pad to prevent any injury to the spinal accessory nerve. The anterior border of
trapezius muscle is skeletonized and then care is taken to identify the spinal accessory nerve.
This can be done either by identifying it as it passes onto the undersurface of the trapezius
muscle in the lower part of the neck. or by identifying it 1 cm superior to Erb's point (which is
a plexus of cervical cutaneous nerves on the posterior border of the sternocleidomastoid muscle
approximately 6 cm from the inferior lobule of the ear). Once identified. the nerve is dissected
out from its entry in the trapezius muscle up to the posterior border of sternocleidomastoid
muscle. The nerve is then followed up through the sternocleidomastoid muscle. dividing the
muscle with electrocautery while protecting the nerve with an Adson clamp under direct vision
at all times.

65.  Retracting the anterior portion of the sternocleidomastoid muscle cephalad and the
posterior portion caudad assists in the dissection of the nerve. The nerve is then
carefully dissected out in a cephalad direction along the lateral border of the internal
jugular vein up to its exit from the jugular foramen at the skull base under the
posterior belly of the digastric muscle. Once this is done the nerve is then carefully
separated from underlying tissue using the Martin forceps and Reynolds scissors. The
superior attachment of the sternocleidomastoid muscle is then detached from the
mastoid process, and fibrofatty tissue lying in the supraaccessory triangle is dissected
off the muscular floor. working from a lateral-to-medial direction. The tissue is
sequentially dissected off the splenius capitis muscle followed by the levator scapulae. At
this point. the tissue is then able to be passed under the dissected accessory nerve
and dissected off the rest of the muscular floor of the posterior triangle. Working in
a lateral-to-medial direction the anterior border of each subsequent muscle is
exposed. The posterior scalene muscle is exposed and then the inferior belly of
omohyoid muscle is divided at its attachment on the scapula. Transverse cervical
vessels are encountered inferiorly and are divided between clamps and ligated with
silk ties. This allows the specimen to be retracted medially:. allowing further
dissection of the muscular floor. first exposing the middle scalene muscle and then
the anterior scalene muscle with the brachial plexus in between. On the anterior
surface of the anterior scalene muscle. the phrenic nerve is identified passing in a
lateral-to-medial direction. Care should be taken not to elevate this nerve with the
overlying block of soft tissue. Once the phrenic nerve is identified and preserved.
the dissection then continues in a cephalad direction, identifying the cutaneous
cervical branches as they separate off the cervical rootlets. These branches are
divided and the stumps of the nerve roots are ligated.

66.  This allows the specimen to be further retracted medially to expose the internal
jugular vein, common carotid artery, and the vagus nerve. At this point. the
specimen is allowed to drop back into its natural position in the posterior triangle.
Attention is then turned to the anterior skin flap. The transverse skin incision is
completed from the trifurcation point up to its medial end. The skin, subcutaneous
tissue, and platysma muscle are divided. and an anterior subplatysmal flap is
elevated up to the midline superiorly and to the medial end of the
sternocleidomastoid muscle at its attachment to the sternum inferiorly. A large loop
retractor is used to increase exposure inferiorly. Using electrocautery with
coagulating current. the sternal and clavicular heads of sternocleidomastoid muscle are
divided. The muscle is then retracted in a cephalad direction and loose areolar
tissue is dissected to expose the carotid sheath. '1he lateral border of the strap
muscles are retracted medially.. allowing the carotid sheath to be fully exposed. The
sheath is opened and the common carotid artery, vagus nerve, and internal jugular
vein identified and dissected. The internal jugular vein is then divided between clamps
and doubly ligated with 2-0 silk ties . A 3-0 chromic catgut transfixion suture is used
to secure the distal end of the vein. Lymphatic tissue lying lateral to the internal
jugular vein encompassing the thoracic duct on the left side and unnamed
lymphatics on the right-hand side of the neck are carefully divided in clamps and
ligated with silk ties to prevent chyle leakage

67.  At this juncture, the proximal portion of the transverse cervical vessels are dissected.
divided. and ligated with 3-0 silk. The soft tissue including sternocleidomastoid muscle
and internal jugular vein, is now retracted in a cephalad direction and carefully
dissected in the avascular plane off the vagus nerve and carotid artery The middle
thyroid vein needs to be identified. divided. and ligated with 3-0 silk as it enters
the medial aspect of the internal jugular vein. Working in a cephalad direction. the
hypoglossal nerve is then identified beyond the bifurcation of the carotid artery.
Additional medial mobilization of the specimen is obtained by dividing the superior
cervical plexus. The anteromedial limit of the dissection is the anterior belly of the
omohyoid muscle. The is incorporated into the specimen by dissecting it up to its
attachment to the hyoid bone. where it is then detached. Careful dissection at this level
allows identification of the superior thyroid vessels. The superior thyroid vein is
divided and ligated and the superior thyroid artery is preserved. The superior skin
flap is then elevated. Having divided the platysma muscle. the fascia on the inferior
aspect of the submandibular gland is divided and dissected allowing the superior skin
flap to be raised in this plane. This allows the marginal mandibular branch of the
facial nerve to be exposed. protected. and preserved. This nerve lies just anterior to
the submandibular fascia and superficial to the posterior facial vein. The vein is
ligated and its upper stump retracted cephalad protecting the marginal branch of
the facial nerve. Anteriorly this dissection is carried out sharply elevating the nerve
with the skin flap. In performing this manoeuvre, the cervical branch of the facial
nerve is identified and it may be divided distal to its separation from the marginal
mandibular branch.

68.  Dissection now proceeds along the lower border of the mandible. The fascial
attachment between the sternocleidomastoid muscle and angle of mandible are
divided and then dissection along the inferior border of the mandible allows the
delivery of the prevascular facial lymph nodes. The facial vein and artery are divided
at this point on the posterior superior aspect of the submandibular gland.
Identification of the anterior belly of the ipsilateral and contralateral digastric muscles
is then carried out.
 Nodal tissue in the submental triangle is dissected out, ligating vessels in the apex
of the triangle with 3-o silk ties. The soft tissue from the submental triangle is then
dissected off the ipsilateral anterior belly of the digastric muscle followed by the
mylohyoid muscle. The neurovascular bundle to the mylohyoid muscle is identified.
divided, and ligated. Several clamps are used to apply gentle traction on the
submandibular gland. allowing it to be mobilized from its bed. A loop retractor is
placed under the free edge of the mylohyoid muscle, retracting it superiomedialy.
This manoeuvre allows exposure of the lingual nerve and the secretomotor fibres to
the submandibular ganglion. These fibres are divided. taking care to protect and
preserve the lingual nerve. Following this, the submandibular duct is dissected.
divided. and ligated.

69.  Care is taken not to enter the fascia of the hyoglossus muscle as it is in this plane
that the hypoglossal nerve is located. The submandibular gland is now retracted
laterally and separated from the posterior belly of the digastric muscle. The
proximal portion of the facial artery is then identified on the posteromedial aspect
of the posterior belly of the digastric muscle. It is divided in clamps and ligated with
3-0 silk . Following this the tail of parotid is retracted cephalad. allowing access to
the posterior belly of the digastric muscle. Several small pharyngeal veins need to be
divided and ligated. After this, the posterior belly of the digastric muscle is retracted
cephalad with a deep right-angled retractor. The occipital artery and vein lying
superficial to the internal jugular vein are divided and ligated. allowing exposure of
the upper end of the internal jugular vein at the base of the skull. The vein is then
skeletonized circumferentially and then doubly ligated with 2-0 silk. The specimen is
then able to be delivered. Meticulous haemostasis is then secured with clips or
electrocautery and the wound irrigated with a plentiful amount of saline. Large
suction drains are inserted through stab incisions in the lower skin flaps. One drain
is placed along the anterior border of the trapezius muscle and held in p06l.tion with
a loop of chromic catgut suture. An anterior drain is placed along the strap muscles.
medial to the carotid artery. and again secured in place with a loop of chromic
catgut suture. Both drains are secured to skin with a purse-string silk suture. The
incision is then closed in two layers using 3-0 chromic catgut interrupted sutures for
the platysma muscle and 5-0 nylon for skin. Suction on the drains is maintained while
the wound is being closed. An airtight closure is required to ensure adherence
between the skin and deep structures of the neck. The drains remain in place for 4 to 7
days and are removed only once minimal serous drainage is present.

72. Thankyou...