an over view of anatomy of neck, defintions and diiferent types of neck dissections

1. Neck Dissections
By
Dr P Lalityaswarna
IInd yr resident

2. Objectives
• Introduction
• History
• Anatomy
• Diagnosis and staging
• Treatment guidelines
• Surgical procedures
Head and Neck cancers

3. Introduction
• Head & Neck cancer - common problem
• Neck secondaries + in > 70% at presentation
• Metastases of Unknown origin(MUO)/ Cancer of
Unknown Primary(CUP) Neck- 5-7%
• Rate of mets in N0 Neck < 20%->50%
• Proper treatment of Neck improves Survival by
50%

4. History
• 1880 - Kocher - Removal of Neck node mets
• 1906 – George Crile – RND
• 1933-41 – Blair and Martin - Popularized RND
• 1953 – Pietrantoni - Spared SAN
• 1967 – Bocca and Pignataro - FND for N0 Neck
• 1975 – Bocca – Established Oncological safety of FND
• 1980 -2016– Various Classifications of NDs

5. Anatomy
• The side of the neck - quadrilateral outline
Posterior
triangleAnterior
triangle

6. Anterior Triangle

7. SUBMENTAL TRIANGLE

8. SUBMANDIBULAR TRIANGLE
•Submandibular triangle is paired
• Arteries
–Facial
–Sublingual
–Submental
•Veins: same as arteries
•Nerves : Mylohyoid and
hypoglossal nerve
•Structures
–Submandibular gland
–Inferior portion of parotid gland
–Submandibular lymph node

9. CAROTID TRIANGLE
•Contains arteries,veins,nerves and structures
Arteries:
–Common carotid (with carotid body)
–Internal carotid (with carotid sinus)
- Superior thyroid
- Lingual
- Facial
-Ascending pharyngeal
- Occipital
Veins:
–Internal Jugalarvein
–Common facial vein
–Lingual Vein
–Superior Thyroid vein
–Middle thyroid vein

10. Carotid triangle
•Nerves
- Vagus
- External laryngeal
- Internal laryngeal
- Spinal Acessory
- Hypoglossal
- Ansacervicalis
- Sympathetic trunk
•Structures
-Larynx
-Thyroid

12. MUSCULAR TRIANGLE
•Arteries
–Superior thyroid
•Veins
–Inferior thyroid
–Anterior jugular
•Nerves: Ansa cervicalis
•Structures
–Strap muscles
–Thyroid gland
–Parathyroid gland
–Larynx
–Trachea
–Esophagus

13. Posterior triangle

14. Contents of Posterior triangle
Nerves:
• Spinal acessory nerve.
• Great auricular
• Lesser occipital
• Branches of Cervical plexus
• Transverse cervical
• Supraclavicular
• Roots and trunks of brachial
plexus.
• Dorsal scapular
• Long thoracic
• Phrenic
•Arteries
–Subclavian artery
–Transverse Cervical artery
–Suprascapular artery
•Vein
–External jugular vein
(terminal part)
•Lymph Nodes
–Occipital
–Supraclavicular

15. • First echelon nodes:
These are the first group of nodes to which
the lymph from a site drains to.
• So they are the first group to be involved by
mets
• Absence of mets in First echelon nodes
indicate absence of mets in other groups in
general

16. • Cervical lymph nodes are classified into groups
by Memorial Sloan Kettering Cancer centre in
the 1930’s

17. Level I: Lymph node groups – submental and
submandibular
• Level Ia*: Submental triangle
Boundaries – anterior bellies of the digastric
muscle and the hyoid bone
• Level Ib*: Submandibular triangle
Boundaries – body of the mandible,
anterior and posterior belly of the digastric
muscle

18. • Level II: Lymph node groups – upper jugular
Boundaries:
1) anterior – lateral border of the sternohyoid muscle
2) posterior – posterior border of the sternocleidomastoid
muscle
3) superior – skull base
4) inferior – level of the hyoid bone (clinical landmark) or
carotid bifurcation (surgical landmark)

19. • Level III: Lymph node groups – middle jugular
Boundaries –
1) anterior – lateral border of the sternohyoid muscle
2) posterior – posterior border of the
sternocleidomastoid muscle
3) superior – hyoid bone (clinical landmark) or carotid
bifurcation (surgical landmark)
4) inferior – cricothyroid notch (clinical landmark) or
omohyoid muscle (surgical landmark)

20. • Level IV: Lymph node groups – lower jugular
Boundaries –
1) anterior – lateral border of the sternohyoid muscle
2) posterior – posterior border of the sternocleidomastoid
muscle
3) superior – cricothyroid notch (clinical landmark) or omohyoid
muscle (surgical landmark)
4) inferior – clavicle

21. • Level V: Lymph node groups – posterior triangle
Boundaries –
1) anterior – posterior border of the sternocleidomastoid
muscle
2) posterior – anterior border of the trapezius muscle
3) inferior - clavicle
Level Va – along the SAN
Level Vb – along the
Transverse cervical artery

22. • Level VI: Lymph node groups – prelaryngeal (Delphian),
pretracheal, paratracheal, and precricoid (Delphian)
lymph nodes - also known as the Anterior compartment.
• Boundaries – 1) lateral – carotid sheath
2) superior – hyoid bone
3) inferior – suprasternal notch

23. • Level VII: Lymph node groups
– Upper mediastinal
Boundaries –
1) lateral – carotid arteries
2) superior – suprasternal
notch
3) inferior – aortic arch

24. Platysma muscle:
• Situated within the superficial fascia of neck

25. Sternocleidomastoid Muscle (SCM)
• invested in the superficial layer of the deep cervical
fascia.

26. Omohyoid muscle Trapezius muscle

27. Digastric Muscle
• “residents friend”.

28. Marginal Mandibular Nerve (ramus mandibularis)
• Extension-The marginal mandibular nerve lies either
along the body of the mandible (80%) or it may briefly
enter the neck, where it lies within 1.2 cm of the lower
border of the body (20%).

29. Spinal Accessory Nerve
• The spinal root of the accessory nerve is a union of
motor neurons whose cell bodies originate in the spinal
nucleus located in the anterior grey column of the spinal
cord.
• course:

30. Brachial Plexus
• Formed by the union of the ventral rami of the lower
four cervical nerves and the greater part of the ventral
ramus of the first thoracic nerve (C5-8 and T1)

31. Phrenic nerve
• The phrenic nerve
comprised of fibers
from cervical roots 3-5
• It runs obliquely
toward the midline
along the anterior
surface of the anterior
scalene muscle and is
covered by
prevertebral fascia

32. Hypoglossal Nerve
• The hypoglossal nerve is
the motor nerve of the
tongue. Its cell bodies
originate in then
hypoglossal nucleus in the
medulla oblongata.
• The nerve exits the skull via
the hypoglossal canal of
the occipital bone.
• As it exits the canal it lies
deep to the IJV, the
internal carotid artery, and
CN IX, X, and XI

33. Ansa cervicalis

34. Thoracic Duct
• In the neck - lies anterior to the vertebral artery and vein,
the sympathetic trunk and the thyrocervical trunk.
• It is separated from the phrenic nerve by the prevertebral
fascia.

35. Presentation of Head & Neck cancers
• Apparent Primary with enlarged nodes
- The N+ Neck
• Apparent Primary with normal neck
nodes - The N0 Neck
• Enlarged neck nodes with no apparent
primary - MUO Neck

36. Diagnosis
• Diagnosis and Staging with Obvious Primary
• Clinical examination
• ? Significant nodes
Size > 1 cm Suspicious > 2cm Significant
- Shape – Round
- Hard
- Fixity

37. • Risk of mets in N0 Neck depends on
-Site -Thickness
-T Status -Depth of invasion
-Morphology -Borders
-Histology - Lymphovascular invasion
-Grade - perineural invasion

39. Metastasis of Unknown Origin(MUO):
• Neck Mass – Site and histology are the most
important indicators of the Primary.
• Complete Head & Neck examination with special
attention to skin
• Palpation of Oropharynx
• Mirror and fibre optic examination of
Nasopharynx , Oropharynx ,Hypopharynx and
Larynx as clinically indicated

41. • FNAC is the key
Squamous Cell Carcinoma
Adenocarcinoma
Thyroid Carcinoma
NPC
Melanoma
• Lymphoma, Poorly Dif.Carcinoma,
Undiff.Malignancy - Needs Biopsy, IHC

42. • Endoscopies based on Symptoms, Site,
Histology
• PET-CT definite Role
• HPV, EBV Testing for SCC, Undiff.Mal
• EUA –Inspection , Palpation , Biopsy of
suspicious Areas, Tonsillectomy

43.  MUO Neck / CUP Neck
Chronically enlarged neck nodes DD
-Carcinoma
-Lymphoma
-Tuberculosis
-Others
Any lymph node enlargement
-Look for primary
- Rest of RES

44. Staging
Regional Lymph Nodes (N):
• Lip, oral cavity, oropharynx, hypopharynx, larynx, trachea,
paranasal sinuses,major salivary glands
 NX - Regional lymph nodes cannot be assessed
 N0 - No regional lymph node metastasis
 N1 - Single ipsilateral lymph node <3 cm
 N2
N2a - Single ipsilateral lymph node 3-6 cm
N2b- Multiple ipsilateral nodes < 6 cm
N2c - Bilateral lymph nodes < 6 cm
 N3 - Any node > 6 cm

45. Nasopharynx:
NX - nodes cannot be assessed
N0 - no regional lymph node metastasis
N1 - Unilateral metastasis in lymph nodes < 6 cm above
the supraclavicular fossa
N2 - Bilateral metastasis in lymph nodes < 6 cm above
the supraclavicular fossa
N3 - Metastasis in a lymph node(s)
• N3a > 6 cm
• N3b extension to the supraclavicular fossa

46. Thyroid:
NX - Regional lymph noses cannot be assessed
N0 - No regional lymph node metastasis
N1 Regional lymph node metastasis
• N1a - Metastasis in ipsilateral cervical lymph node(s)
• N1b - Metastasis in bilateral, midline, or
contralateral cervical or mediastinal lymph node(s)

47. Treatment guidelines
• Practically every patient with Head and Neck Cancer
needs treatment of Neck
• Primary found – Treat as per Primary
• Primary not found
Operable – Surgery+PORT (Include NP)
Inoperable – RT – Reassess for Surgery
• Prognosis depends on stage as if primary is under
control

48. • N0 Neck must be treated if risk is >20%
• N0 Neck – RT if Primary treated with RT
• N0 Neck–Surgery if Primary treated with
Surgery
• N1 - Surgery/RT Based on Primary →
RT/Surgery as needed
• N2-N3 – Surgery→ PORT

49. • Surgery – The “Gold Standard” Management

50. Classification of Neck dissections
• Committee for Head and Neck Surgery and Oncology of
the American Academy of Otolaryngology/Head and
Neck Surgery(1991):
1) Radical neck dissection (RND)
2) Modified radical neck dissection (MRND)
3) Selective neck dissection (SND):
a. supra-omohyoid type
b. lateral type
c. posterolateral type
d. anterior compartment type
4) Extended radical neck dissection

51. Medina’s classification: 1989
1) Comprehensive neck dissection
• Radical neck dissection
• Modified radical neck dissection
- Type I (XI preserved)
- Type II (XI, IJV preserved)
- Type III (XI, IJV, and SCM preserved)
2) Selective neck dissection

52. • When Neck Dissection is done in N0 Neck it is called
Elective Neck Dissection
• This is called ‘ Elective’ as we elected to do it even
though there is no evidence of disease
• Selective Neck Dissections should be done in the
setting of Elective Neck Dissection only i.e. in N0
Neck only .
• SNDs should always be followed by postop
radiotherapy

53. Radical neck dissection
• Gold Standard
• It involves removal of levels I-V, few nodes located in the
tail of the parotid gland, the perifacial and buccinator
nodes, the retropharyngeal nodes, and the paratracheal
nodes.
• In addition,removal of nonlymphatic structures including
the SAN,IJV,SCM.
Indications:
• Extensive cervical lymph node metastasis and/or
extension beyond the capsule with invasion into the
spinal accessory nerve, IJV, and SCM.

55. Modified Radical Neck Dissection
• Modified radical neck dissection involves excision of
the level I-V lymph nodes bearing tissues from one
side of the neck with the preservation of one or
more nonlymphatic structure including the spinal
accessory nerve, the IJV, or the SCM.
• Medina subclassifies the MRND into Types I-III
• MRND is analogous to the “functional neck
dissection”

56. Indications
• Gross nodal metastasis to the neck that does not directly
infiltrate or adhere to the non-lymphatic structures.
• Bilateral MRND - contralateral nodal involvement.
• Here,it is important to plan ahead if sacrifice of both IJVs
is anticipated because bilateral resection results in
massive edema and cases of blindness (ischemic optic
neuropathy), stroke, and death have been reported.

57. Rationale
• Modifications of the classic RND aim to reduce
postsurgical neck pain and shoulder dysfunction
encountered when the spinal accessory is resected
without compromising adequate oncologic treatment.
• Sacrifice of the SCM and IJV is less debilitating
• SCM preservation - improves cosmetic appearance and
protects the carotid artery if adjuvant radiotherapy is
employed.
• Preserving the IJV becomes more significant in patients
requiring bilateral neck dissections.

58. • MRND type II is rarely planned, as it is uncommon for
metastatic disease to invade the SCM and not the IJV so
when gross invasion of the SCM is not seen preservation
of both the SCM and IJV should be considered.
• MRND Type III evolved from work by Suarez (1963) who
observed in autopsy and surgical specimens of the larynx
and hypopharynx that the lymph nodes were in fibrofatty
tissue, and even when near blood vessels but did not
share the same adventitia.

60. Management of Secondaries Neck

61. Management of Secondaries Neck

62. Selective neck dissection
• Definition:
- cervical lymphadenectomy with
preservation of one or more grps of lymphnodes
Four common subtypes:
1. Supraomohyoid neck dissection
2. Posterolateral neck dissection
3. Lateral neck dissection
4. anterior neck dissection

63. SND: Supraomohyoid type
• Most commonly performed SND
• Definition: enbloc removal of cervical
lymohnodes levels I – III
• Posterior limits – cervical plexus and posterior
border of SCM
• Inferior limit is the omhyoid muscle overlying the
IJV
• INDICATION: oral cavity carcinoma with N0 neck

66. SND: Lateral type
• Defintion: Enbloc removal of the jugular
lymphnodea – levels II- IV
• Indications: carcinomas of oropharynx,hypopharynx,
supraglottis,larynx

67. SND: Anterior compartment
• Definition: Enbloc removal of lymph structures in level
VI
• Limits of dissection – hyoid bone,suprasternal notch,
carotid sheaths
Indications:
• Selected cases of ca. Thyroid
• Parathyroid carcinoma
• Suglottic carcinoma
• Laryngeal carcinoma with subglottic extension
• Carcinoma of the cervical oesophagus

70. SND: Posterolateral type
Definition: Enbloc excision of
lymph bearing tissues of level
II – V and additional node grps
– suboccipital , postauricular
Indications:
• Cutaneous malignancies –
Melanoma,SCC, Merkel cell
carcinoma
• Soft tissue sarcomas of scalp
and neck

71. Extended radical neck dissection

72. Pre-op considerations:
• Pre-op counselling.
• Reserve 2 units of Packed RBC.
• Pre-op antibiotics
• Measures to secure airway – fiber optic intubation /
tracheostomy
• Plan and mark the incision
• Local infiltration - 1% lidocaine with 1:1,00,000 epinephrine

74. Procedure

75. • Anesthesia :General endotracheal anesthesia
• Position: supine position with the head elevated to
30 degrees.
• The neck is hypererxtended and rotated to the
opposite side.
Incision:
• For MRND type l - a single trifurcate neck incision is
the most frequently employed incision
Neck dissection

76. Complications
• Hemorrhage,shock
• Carotid Blow out – occurs in 7-14 days
-due to sepsis,wound breakdown,arterial
adventitious stripping and necrosis
• Flap necrosis
• Infection
• Lymph ooze
• Seroma formation
• Frozen shoulder

77. Conclusions
• Almost every Pt with Head and Neck Cancer needs
treatment of Neck
• Proper management of Neck results in almost 100%
control of neck with 50% ↑ Survival
• Sound understanding of anatomy and patterns of
spread has reduced the morbidity of Neck
Dissections with introduction of MRND and SND

78. References
• Fischer Mastery of Surgery,6th Edition
• ZOLLINGER’S atlas of surgical operations
• Farquharson’s textbook of operative general
surgery
• Jatin shah Head and Neck surgery and oncology
• Skandalakis surgical anatomy
• Sabiston text book of 19th edition
• Netter atlas of anatomy