This document describes the anatomy of the neck relevant to neck dissection surgery. It outlines the boundaries of the neck, key muscles and structures like the platysma, sternocleidomastoid, trapezius and vessels. It discusses the lymph node levels and types of neck dissection surgeries like radical and selective dissections. The document provides details of the surgical approach including skin incisions and dissection of structures to completely remove lymph nodes while preserving nearby nerves and vessels.

1. Neck Dissection
Dr Yasha Gupta
LADY HARDINGE MEDICAL COLLEGE

2. Neck Boundaries
1 = Mandible
2 = Zygomatic Process Of The
Temporal Bone
3 = External Auditory Canal
4 = Mastoid
5 = Superior Nuchal Line
6 = External Occipital Protuberance
7 = Manubrium Sterni
8 = Clavicle
9 = Acromioclavicular Joint
10 = Spinous Process Of Seventh
Cervical Vertebra

3. The Surgical Anatomy
Platysma muscle:
Wide muscular sheet embedded in superficial fascia
Origin
Insertion
Action
Skin flap

4. The Surgical Anatomy
Sternocleidomastoid Muscle:
Differentiated from the platysma by the direction of its fibres
Crossed by the IJV and the great auricular nerve
Origin
Insertion
Nerve supply
Action
boundary of posterior triangle & nodes level II - IV

5. Change to picture with labels
sterno mastpoid

6. The Surgical Anatomy
Trapezius muscle:
Origin
Insertion
Nerve supply
Action

7. The Surgical Anatomy
Digastric Muscle
Posterior belly, intermediate tendon, anterior belly
Origin
Nerve supply
The external and internal carotid artery, 12th
& 11th
cranial nerves
and the IJV lie medial

9. The Surgical Anatomy
Omohyoid Muscle:
Superior & inferior bellies, intermediate tendon
Origin
Nerve supply
Action
Surgical landmark for nodal levels III and IV
The inferior belly is superficial to the brachial plexus, phrenic nerve
and transverse cervical vessels
The superior belly is superficial to the IJV

10. Blood Supply of
Head & Neck

11. Arteries of Head & Neck
• Common Carotid Artery
• External Carotid Artery
• Internal Carotid Artery
• Subclavian Artery

12. Common Carotid Arteries
Right Common Carotid Artery:
 Arises from brachiocephalic artery
(Behind right sternoclavicular joint)
Left Common Carotid Artery:
 Arises from Arch of Aorta
 Runs upwards in the neck from sternoclavicular
joint to upper border of thyroid cartilage

13. Common Carotid Arteries

14. Relations of Common Carotid Artery
Anterolaterally:
 Sternocleidomastoid
 Sternohyoid
 Sternothyroid
 Superior belly of omohyoid
Posteriorly:
 Prevertebral muscles
Medially:
 Larynx
 Pharynx
Laterally:
 Internal jugular vein

15. Branches of Common Carotid Artery
 External Carotid Artery
 Internal Carotid Artery

16. Common Carotid Arteries

17. Branches of External Carotid Artery
 Superior thyroid artery
 Ascending pharyngeal artery
 Lingual artery
 Facial artery
 Occipital artery
 Posterior auricular artery
 Superficial temporal artery
 Maxillary artery

18. Internal Carotid Artery
 Begins at the level of upper border of thyroid
cartilage
 No branches in the neck
 Through carotid canal enters into cranial cavity
 Supplies brain, eyes, forehead and part of the nose

19. Subclavian Artery
Right Subclavian Artery:
 Arises from brachiocephalic artery
(Behind right sternoclavicular joint)
 At outer border of 1st
rib it becomes Axillary Artery
Left Subclavian Artery:
 Arsis from Arch of Aorta in the thorax
 Runs upwards to the root of the neck & arches

20. Jugular Vein
INTERNAL JUGULAR
VEIN
ANTERIOR JUGULAR VEIN
EXTERNAL JUGULAR
VEIN

21. External jugular Vein
 Formed behind the angle of jaw by the union of
Posterior branch of retromandibular vein with
posterior auricular vein.
 It drains into subclavian vein
 Tributaries:
 Posterior external jugular
 Transverse cervical


22. Internal jugular Vein
 Receives blood from brain, face and neck.
 Continuation of sigmoid sinus and leave the skull from jugular foramen.
 Ends by joining subclavian vein to form brachiocephalic vein.
• Tributaries:
 Facial vein
 Pharyngeal vein
 Lingual vein
 Superior thyroid vein
 Middle thyroid vein

23. The Surgical Anatomy
Spinal Accessory nerve: SAN
Emerge from the jugular foramen medial to the digastric
and stylohyoid muscles and lateral and posterior to IJV
It passes obliquely downward and backward to reach the
medial surface of the SCM near the junction of its
superior and middle thirds, Erb’s point

24. The Surgical Anatomy
Thoracic duct:
• Conveys lymph from the entire body back to the blood
• Begins at the cisterna chyli
• Enters posterior mediastinum between azygous vein & thoracic
aorta
• Courses to left into neck anterior to the vertebral artery and vein
• Enters the junction of the left subclavian vein and the IJV

26. Triangles Of The Neck
29
Stylohyoid
Mandible
Digastric
Digastric
triangle
Submental
triangle
Carotid triangle
Muscular
triangle
Omohyoid
ANTERIOR
TRIANGLE
Sternocleidomastoid
Trapezius
Occipital
triangle
Supraclavic
ular triangle
POSTERI
OR
TRIANGLE

27. Anterior Triangle
Boundaries
Sub-mental triangle
Digastric triangle
Carotid triangle
Muscular triangle

28. Posterior Triangle
Boundaries
Contents

29. Lymph Node Levels/Nodal Regions
Developed by Memorial Sloan-Kettering Cancer Center
Ease and uniformity in describing regional nodal
involvement

30. AAOHNS Classification Of Cervical
Lymph Nodes
LEVEL I – Submental /
Submandibular Lymph Nodes
LEVEL II – Upper Jugular Lymph
Nodes
LEVEL III – Middle Jugular Lymph
Nodes
LEVEL IV– Lower Jugular Lymph
Nodes
LEVEL V – Posterior Triangle
Lymph Nodes
LEVEL VI –Anterior Compartment
Lymph Nodes
LEVEL VII- Superior Mediastinal
Lymph Nodes
VIVI

31. Metastatic Nodal Disease
Level I – lip, anterior tongue, anterior floor of mouth, buccal
mucosa
Level II, III – tonsil, base of tongue (scalp, external auditory
canal)
Level IV – hypopharynx & larynx
Level V – nasopharyngeal malignacy
Level VI – thyroid, subglottic

32. Clinical Staging
 Joint UICC/AJCC classification (2009)
 Not only for presence of lymph node but also size, number & laterality
 Applies for all head & neck tumour except nasopharynx, thyroid
 Only clinical classification

33. Staging Of The Neck
NX: Regional lymph nodes cannot be Assessed
N0: No regional lymph node metastasis
N1: Metastasis in a single ipsilateral lymph node, < 3cm
N2a: Metastasis in a single ipsilateral lymph node 3 to 6 cm

34. Staging of the Neck
N2b: Metastasis in multiple ipsilateral
lymph nodes, none more than 6 cm
N2c: Metastasis in bilateral or contralateral
nodes < 6cm
N3: Metastasis in a lymph node more than
6 cm in greatest dimension

36. Nasopharyngeal Carcinoma
N1 – Unilateral < 6cm
N2 – Bilateral < 6 cm
N3a > 6 cm
N3b – Extension to supraclavicular fossa
Thyroid
N1 – Regional node
N1a - Ipsilateral
N1b - Bilateral, midline, contralateral cervical or
mediastinal LN

37. Types Of Neck Dissection
Radical neck dissection
Modified radical dissection
Selective neck dissection
Extended radical neck dissection

38. Classification of Neck
Dissections
Academy’s classification
– Based on 4 concepts
1. RND is the standard basic procedure for cervical lymphadenectomy
against which all other modifications
2. Modifications of the RND which include preservation of any non-
lymphatic structures are referred to as modified radical neck
dissection (MRND)

39. Classification of Neck
Dissections
3) Any neck dissection that preserves one or more groups or levels of
lymph nodes is referred to as a selective neck dissection (SND)
4) An extended neck dissection refers to the removal of additional
lymph node groups or non-lymphatic structures relative to the RND

40. Skin Incision
Vascularisation of flaps
Exposure
Protection of major vessels
Localization of primary tumour
Consider previous radiotherapy & reconstruction
Cosmesis
Previous surgical field

41. Blood Supply Of Cervical Neck Skin
Blood enters from above, below and either
side with a resultant watershed in the
middle of the neck. Incisions can be
planned to utilize this so as to maximize
blood supply to each of the neck flaps.

46. Radical Neck Dissection
Lymph nodes level I – V
Non-lymphatic structures
Accessory nerve
Internal jugular vein
Sternocleidomastoid muscle

47. Indications
Significant operable neck disease (N2a,N2b,N3) with spinal
accessory or IJV involvement
Extensive recurrent disease after previous selective surgery

48. Contraindication
Untreatable primary tumour or unresectable neck disease
Patient unfit
Distant metastasis
Simultaneous bilateral dissection

49. Surgical Boundaries
Superior- angle of mandible
Anterior- contralateral anterior belly of digastric
Inferior- clavicle
Posterior- anterior border of trapezius

50. With traction and countertraction, the skin is incised in one
movement with a No. 10 blade through the platysma muscle
In the posterior part of the neck, the fibers of the sternomastoid
muscle are inserted directly into the skin which makes the
dissection and identification of the appropriate plane more
difficult.

51. Marginal mandibular nerve
Cervical branch of facial nerve
Both nerves curve downwards below and in front of the angle of the
mandible across the facial vessels about one finger‘s breadth below
the mandible .
The marginal mandibular nerve then runs Immediately superior to the
submandibular gland while the cervical branch runs lateral and
inferior to this gland . Both of the nerves then curve upwards again

52. 2 approaches can be used
Hayes martin (upward approach)
Downward approach

53. Hayes Martin Approach
Sternocliedomastoid is divided just above sterno clavicular attachment
Internal jugular vein identified
Carotid sheath is opened to expose internal jugular vein & ligated
The dissection extends laterally to approach chaissaignac's triangle.
Divide and retract the omohyoid muscle upwards.
Mobilize the fat pad overlying the prevertebral fascia.
Identify and preserve the brachial plexus and phrenic nerve.

57. Dissection Of The Posterior Triangle
Dissection continues up the anterior border of trapezius to the
mastoid tip
First accessory nerve is identified
Branches from cervical plexus C3,4 are saved
Accessory nerve dissected away from muscle
Upper end of sternocleidomastoid is cut under tension &
digastric is retracted to show IJV

59. Division of upper end of IJV
Identify and preserve the hypoglossal nerve.
Specimen is mobilized both top and bottom
Top section is completed by finding and ligating the posterior
branch of the posterior facial vein.
The dissection of the posterior triangle is completed by lifting the
specimen & dissect between the contents of the posterior triangle
and prevertebral fascia.

60. Dissection of the Submandibular
Triangle
 The fat is divided in the submental area and anterior belly of digastric is
identified.
 The anterior part of the submandibular gland is then identified and is
dissected to the posterior border of the mylohyoid muscle.
 The upper border of the submandibular gland is freed by dividing and tying
the Vessels
 The lingual nerve is identified, branch to the submandibular ganglion is
divided
 The submandibular duct is tied and divided
 Facial artery is divided and specimen is removed

62. Above Downward Approach
 Incision given and flaps are raised
 Clearance of posterior triangle
 Incision along anterior border of trapezius and SCM s divided
 Posterior belly of digastric is identified
 Clearance proceed downwards
 Accessory nerve, inferior belly of omohyoid, transverse cervical vessels,
brachial plexus covered with fascia identified

63.  Supraclavicular dissection
 Fat is divided to locate inferior belly of omohyoid
 Omohyoid is divided and dissection is continued upto the level of prevertebral fascia
 External jugular vein is divided
 SCM is divided at it’s lower end
 IJV is dissected and divided
 Clearance is continued from posterior triangle to midline
 Clearance is done close to artery and nerve
 Tributaries of IJV are carefully divided
 Submandibular triangle clearance

64. Modified Neck Dissection
Medina classification (1989)
Modified radical neck dissection
– Type I (XI preserved)
– Type II (XI, IJV preserved)
– Type III (XI, IJV, and SCM preserved)

65. MRND Type I

66. Indications
Operable palpable neck disease ( N1, N2a, N2b) not
involving the accessory nerve
N0 neck (occasionally)

67. MRND Type II

68. MRND Type III

69. Indications
Treatment of No neck disease
Treatment of undifferentiated thyroid cancer
Skin tumours eg. Melanoma, SCC

70. Approaches for MRND
Anterior approach (Ballantyne)
Posterior approach (Bocca)

77. Selective Neck Dissection
Any type of cervical lymphadenectomy with preservation of one
or more lymph node groups
Four subtype:
Supraomohyoid neck dissection
Posterolateral neck dissection
Lateral neck dissection
Anterior neck dissection

78. Removal of lymph nodes
in regions I –III
The posterior limit
The inferior limit
SCC oral cavity (T1-T4) with
N0
Single palpable LN in level I or
II (controversial) with Ca oral
cavity, lip

79. Posterolateral Neck Dissection
Removal of levels II-V
Skin cancer posterior to
tragus

80. Lateral neck dissection
Remove lymph nodes in
levels II – IV
Ca larynx, orophaynx,
hypopharynx T2-4 N0

81. Anterior Neck Dissection
Removal of LN surrounding the
visceral structure in the anterior
aspect of the neck, level VI
Superior limit
Inferior limit
Laterally
Differentiated and medullar Ca
of thyroid with thyroidectomy

82. Extended Radical Neck Dissection
Removal of additional lymphatic structure other than RND
Retrophayngeal LN
Level VII LN
Hypoglossal nerve
Carotid artery
Skin of neck

83. Complications
General
Local

84. General Complications
Anaesthetic complications
Post operative atelectasis with basal collapse
Pneumonia
Ischaemic heart diaease
Urinary retention
Deep vein thrombosis

85. Local Complications
Hemorrhage
Wound infection
Carotid artery rupture
Nerve injuries
Chylous fistula
Pneumothorax
Cerebral edema

86. ThankYou