2. FASCIAL LAYERS OF THE NECK
Superficial cervical fascia
Deep cervical fascia
Superficial layer
SCM,
Strap muscles,
Trapezius
Middle or Visceral Layer
Thyroid
Trachea
Esophagus
Deep layer (also prevertebral fascia)
Vertebral muscles
Phrenic nerve
3. FASCIA OF NECK
Superficial fascia:
- Connective tissue below
dermis
- Completely surrounds neck -
thin and hard to demonstrate
- Contains Platysma
4. DEEP CERVICAL FASCIA
Form the boundaries of compartments
Used as a guide to surgical dissection
Allow the neck structures to glide past one another
Supports the thyroid, lymph nodes and blood vessels
Fascial spaces can communicate infection or fluid to
other regions of the body
8. Platysma
•Muscle of Facial Expression
•Innervated by the cervical
branch of the facial nerve
•Blood supply to skin through
this muscle
•Strength to flap
9. EXTERNAL JUGULAR
VEIN
• The vein is formed by the union of the
posterior division of the retromandibular
vein with the posterior auricular vein and
begins near the mandibular angle just
below or in the parotid gland.
• It descends from the angle,
running obliquely, superficial
to the sternocleidomastoid, to
the root of the neck.
• Here it crosses the deep fascia and ends in
the subclavian vein, behind the clavicle.
10. MARGINAL MANDIBULAR NERVE
Present-
Superficial layer of deep cervical
fascia and advantasia of facial vein
More than one branch often present
Should be preserved in neck
dissections
Can be preserved by-
Identifying then dissecting along its
course and reflecting superiorly it flap
12. STERNOCLEIDOMASTOID MUSCLE
(SCM)
• Origin –
1) medial third of the clavicle
(clavicular head)
2) manubrium (sternal head)
• Insertion – mastoid process
• Nerve supply – spinal accessory
nerve (CN XI)
• Blood supply –
1. occipital a. or direct from ECA
2. superior thyroid a.
3. transverse cervical a.
13. OMOHYOID MUSCLE
• Origin – upper border of the scapula
• Insertion –
Intermediate tendon
1. hyoid bone lateral to the sternohyoid muscle
• Blood supply – Inferior thyroid a.
Innervation – Upper belly-Superior root of ansa
Inferior belly- Ansa Cervicalis
• Function –
1. depress the hyoid
2. tense the deep cervical fascia
14. OMOHYOID MUSCLE
Surgical considerations
– Landmark demarcating level III from IV
– Inferior belly lies superficial to
• The brachial plexus
• Phrenic nerve
• Transverse cervical vessels
– Superior belly lies superficial to IJV
15. DIGASTRIC MUSCLE
• Origin – digastric fossa of the mandible (at
the symphyseal border
• Insertion –
1) hyoid bone via the intermediate tendon
2) mastoid process
• Function –
1) elevate the hyoid bone
2) depress the mandible (assists
lateral pterygoid)
17. DIGASTRIC MUSCLE
Intermediate tendon-
Associated superficially with-
• Submandibular gland
• Facial artery
o Anterior belly
• Landmark for identification of mylohyoid for
dissection of the submandibular triangle
18. TRAPEZIUS MUSCLE
• Origin – 1) medial 1/3 of the sup. Nuchal line
2) external occipital protuberance
3) ligamentum nuchae
4) spinous process of C7 to T12
• Insertion – 1) lateral 1/3 of the clavicle
2) acromion process
3) spine of the scapula
• Function – elevate and rotate the scapula and
stabilize the shoulder
23. Submental Triangle
formed by
• the anterior bellies of
the digastric,
• hyoid,
Content-
• Submental lymph nodes;3 or 4 in
no. situated in the superficial fascia
below the chin
• Submental branch of facial artery
• Commencement of ant. Jugular
vein
Floor- mylohyoid
26. Muscular Triangle
formed by
the midline, superior belly of
the omohyoid, and SCM
CONTENT
• No significant structures
• Beneath its floor lie thyroid
glands,larynx,trachea,esophagus
• Infrahyoid muscle are present in this
triangle
31. CONTENTS OF SUBMANDIBULAR TRIANGLE
• Submandibular gland and its lymph
nodes
• Subamdibular duct
• Facial vein
• Facial artery
• Hypoglossal nerve and
accompanying vein
• Lingual artery
32. CONTENTS OF CAROTID TRIANGLE
CCA and its two terminal branches
In the carotid triangle the ICA is posterolateral while
ECA is anteromedial
Branches of ECA
1. Superior thyroid artery
2. Lingual artery
3. Facial artery
4. occipital artery
5. Ascending pharyngeal artery
INT CAROTID artery does not give any branches in
this triangle
Arteries
33. NERVES IN CAROTID TRIANGLE
Portion of spinal part of
accessory nerve
Loop of hypoglossal
Ansa Cervicalis
Vagus nerve; passes downward
within carotid sheath between
IJV laterally and carotid system
of arteries medially
34. SPINAL ACCESSORY NERVE
• Originates from jugular foramen
• Crosses the IJV
• Downward backward to upper part of SCM
• Descends obliquely in level II (forms Level IIa
and Iib
• Penetrates the deep surface of the SCM
• Exits posterior surface of SCM deep to Erb’s
point
•
35. SPINAL ACCESSORY NERVE
• In posterior triangle and lies between
superficial cervical fascia and prevetebral
fascia ;above the levator scapulae
• Before it enters SCM joined by C2
• Before it enters Trapizus joined by C3 and C4
• Enters the trapezius approx. 5 cm above the
clavicle
36. CLINICAL SIGNIFICANCES
While operating in the posterior triangle one should
keep in mind that this nerve runs in the roof and not
floor and hence can be damaged during elevation
of flap itself.
Damage to spinal accessary leads to-
Paralysis of SCM and Trapizius
• leading to asymmetric neckline
• a drooping shoulder
• Winged Scapula
• weakness of forward elevation of the shoulder
37. ERB’S POINT
• At posterior border of the SCM where the four
superficial branches of the cervical plexus emerge
from behind the SCM.
greater auricular
lesser occipital
transverse cervical
supraclvicular nerve
• approximately at the junction of the upper and
middle thirds of this muscle.
• the accessary nerve courses through the to enter
the anterior border of the trapizius muscle
• The spinal accessory nerve can often be found 1 cm
above Erb's point
39. ANSA CERVICALIS
• Part of the cervical plexus
•
• It lies superficial to the IJV in carotid
triangle.
• Superior root
• Inferior root
• Branches from the ansa cervicalis
innervate
• sternothyroid
• sternohyoid
• omohyoid muscles .
40. VEINS PRESENT IN THE CAROTID TRIANGLE
Internal jugular vein; extends
from the base of skull to the
root of neck and collects
blood from the brain
,superficial part of the face
and neck
Also present are the
tributaries of IJV such as
sup. Thyroid, lingual
,common facial,
pharyngeal,and sometimes
occipital veins
41. LIGATION OF INTERNAL JUGULAR VEIN
Lower end of internal jugular vein is approached first by
dividing the SCM because it reduces chances of air emboli
and vessel doesn't get collapsed.
Care should be taken not to harm a thoracic duct
Upper end can be identify by dividing SCM
The position can be located by palpation of transverse portion
of atlas over which it lies .
42. CONTENTS OF OCCIPITAL TRIANGLE
Cutaneous branches of cervical
plexus
1. lesser occipital nerve(c2)
2. great auricular nerve(c2,c3)
3. transverse cervical nerve(c2,c3)
4. Supraclavicular nerve(c3,c4)
• Lies on levator scapulae and
Saclenus medius muscle
• Lies deep to Prevertibral fascia,
IJV , SCM
44. PHRENIC NERVE
Formed by nerve roots C3-5
Runs obliquely toward midline on the anterior surface of
anterior scalene
Covered by prevertebral fascia
Lies directly on anterior surface of anterior scalene muscle
Lies posterior and lateral to the carotid sheath
Sole nerve supply to the diaphragm
45. CONTENTS OF POSTERIOR TRIANGLE
OCCIPITAL
ARTERY
GREAT
AURICULAR N.
LESSER
OCCIPITAL N.
ACCESSORY N.
SUPRA
CLAVICULAR
NERVES
TRANSVERSE
CERVICAL
NERVE
EXTERNAL
JUGULAR
VEIN
46. CONTENTS OF SUPRACLAVICULAR TRIANGLE
[1]nerves-
(a)trunks of brachial plexus
[2]vessels-
(a)Third part of subclavian
artery and subclavian vein
(b)Suprascapular artery and
vein
(c) transverse cervical artery
(d)Lower part of external
jugular vein
[3]lymph nodes-
[4] Thorasic duct
47. POSTERIOR TRIANGLE - deeper
BRACHIAL
PLEXUS ROOTS
&TRUNKS
TRANSVERSE
CERVICAL
ARTERY
SUPRASCAPULAR
ARTERY
SUBCLAVIAN
ARTERY
PHRENIC NERVE
NOSE
SUBCLAVIAN
VEIN
NOTE: SUBCLAVIAN VEIN IS NOT IN POSTERIOR TRIANGLE
48. THORACIC DUCT
• Conveys lymph from the entire
body back to the blood
• Enters the base of neck lies
between right subclavian and
CCA
• Arches upwards, forwards
laterally runs infront of vertibral
artery
• Arches above subclavian artery
passes between IJV and
ant.scalene
• Enters the junction of the left
subclavian and the IJV
49. CLINICAL CONSIDERATION THORACIC DUCT
Injury to thoracic duct may lead to Chyle leak
Chyle extravasation can result in
• delayed wound healing
• dehydration
• malnutrition
• electrolyte disturbances
• immunosuppression
o Prompt identification and treatment of a chyle leak
are essential for optimal surgical outcome
50. CLINICAL CONSIDERATION THORACIC DUCT
Intraoperative Diagnosis of Chyle leak-
• Maneuvers that increase intrathoracic or intra-abdominal
pressure may facilitate the identification of a CL as well.
• Trendelenburg positioning and Valsalva maneuver while the
anesthesiologist applies positive pressure to raise
intrathoracic pressure
• manual abdominal compression
• Can propagate hydrostatic forces through the course of the
thoracic duct to increase chyle flow
• Distend the distal thoracic duct to improve visibility.
51. CLINICAL CONSIDERATION THORACIC DUCT
Management- intraoperative Chyle leak
• Thoracic duct may be ligated with surgical clips or
nonabsorbable suture.
• Locoregional flaps may be incorporated for additional
coverage of the surgical bed.
• The clavicular head of the sternocleidomastoid can be
dissected free and sutured to the wound bed
52. CLINICAL CONSIDERATION THORACIC DUCT
Postoperative Diagnosis of Chyle leak-
• Increases in drain output, especially following resumption of
feedings that contain fat .
• Neck may exhibit erythema, lymphedema, or a palpable fluid
collection in the supraclavicular region.
• Creamy or milky drain contents.
• Drain fluid with triglyceride level >100 mg/dL
58. CLASSIFICATION OF NECK DISSECTIONS
61
• Academy’s Committee for Head and Neck
Surgery and Oncology publicized standard
classification system
59. CLASSIFICATION OF NECK DISSECTIONS
62
• Academy’s classification
– 1) Radical neck dissection (RND)
– 2) Modified radical neck dissection (MRND)
– 3) Selective neck dissection (SND)
• Supra-omohyoid type
• Lateral type
• Posterolateral type
• Anterior compartment type
– 4) Extended radical neck dissection
60. CLASSIFICATION OF NECK DISSECTIONS
63
• Medina classification (1989)
– 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)
– Selective neck dissection
61. CLASSIFICATION OF NECK DISSECTIONS
• Spiro’s classification
– Radical (4 or 5 node levels resected)
• Conventional radical neck dissection
• Modified radical neck dissection
• Extended radical neck dissection
• Modified and extended radical neck dissection
– Selective (3 node levels resected)
• SOHND
• Jugular dissection (Levels II-IV)
• Any other 3 node levels resected
– Limited (no more than 2 node levels resected)
• Paratracheal node dissection
• Mediastinal node dissection
• Any other 1 or 2 node levels resected
62. RADICAL NECK DISSECTION
65
Definition-
All lymph nodes in Levels I-V
including spinal accessory nerve
(SAN), SCM, and IJV
Indications-
Extensive cervical involvement
or matted lymph nodes with
gross extracapsular spread and
invasion into the SAN, IJV, or
SCM
–
63. MODIFIED RADICAL NECK DISSECTION
66
• Type I:Preservation of SAN
• Type II: Preservation of SAN
and IJV
• Type III: Preservation of SAN,
IJV, and SCM ( “Functional
neck dissection”)
64. SELECTIVE NECK DISSECTIONS
68
• Definition
– Cervical lymphadenectomy with preservation of one
or more lymph node groups
– Four common subtypes:
• Supraomohyoid neck dissection
• Posterolateral neck dissection
• Lateral neck dissection
• Anterior neck dissection
65. SND: SUPRAOMOHYOID TYPE
• Most commonly performed
SND
• Definition
– En bloc removal of cervical
lymph node groups I-III
– Posterior limit is the
cervical plexus and
posterior border of the
SCM
– Inferior limit is the omohyoid
muscle overlying the IJV
66. SND: SUPRAOMOHYOID TYPE
70
• Indications
– Oral cavity carcinoma
• Subsites - Lips, buccal mucosa, upper and lower alveolar
ridges, retromolar trigone, hard palate, and anterior 2/3s of
the tongue and FOM
– Bilateral SOHND
• Anterior tongue
• Oral tongue and FOM that approach the midline
– SOHND + parotidectomy
• Cutaneous SCCA of the cheek
• Melanoma (Stage I – 1.5 to 3.99mm) of the cheek
67. SND: LATERAL TYPE
71
• Definition
– En bloc removal of the jugular lymph
nodes including Levels II-IV
• Indications
– N0 neck in carcinomas of the
oropharynx, hypopharynx,
supraglottis, and larynx
68. SND: POSTEROLATERAL TYPE
• Definition
– En bloc excision of lymph bearing tissues in Levels II-IV and
additional node groups – suboccipital and postauricular
• Indications
– Cutaneous malignancies
• Melanoma
• Squamous cell carcinoma
• Merkel cell carcinoma
– Soft tissue sarcomas of the scalp and neck
69. SND: ANTERIOR COMPARTMENT
• Definition
– En bloc removal of lymph structures in Level VI
• Perithyroidal nodes
• Pretracheal nodes
• Precricoid nodes (Delphian)
• Paratracheal nodes along recurrent nerves
• Indications
– Selected cases of thyroid carcinoma
– Parathyroid carcinoma
– Subglottic carcinoma
– Laryngeal carcinoma with subglottic extension
– CA of the cervical esophagus
70. EXTENDED NECK DISSECTION
• Definition
– Any previous dissection which includes removal of one or more
additional lymph node groups and/or non-lymphatic structures.
– Usually performed with N+ necks in MRND or RND when
metastases invade structures usually preserved
• Indications
– Carotid artery invasion
– Other examples:
• Resection of the hypoglossal nerve resection or digastric
muscle,
• dissection of mediastinal nodes and central compartment
for subglottic involvement
• removal of retropharyngeal lymph nodes for tumors originating in
the pharyngeal walls.
71. REFERENCES
• Gray H. Anatomy Descriptive and Surgical:(" Gray's
Anatomy"). Classics of Medicine Library; 1981
• Netter FH. Atlas of Human Anatomy, Saunders Elsevier,
2014: Atlas of Human Anatomy. Bukupedia; 2014 Nov 14
• Textbook of Surgical Anatomy- Hollingshead
• Shah JP, Johnson NW, Batsakis JG. Oral cancer. CRC Press;
2002 Dec 19
• Press CR. Stell & Maran's textbook of head and neck surgery
and oncology. CRC Press; 2011 Dec 30
The various structures of neck are surrounded by different facias which is actully a thickening of connective tissue
Contains variable amount of fat
Platysma is embeded in this region
Supeerficial layer of dCp thoughy to arise from vertebral spinous process enclosing trapizius muscle two layers unite runs forwards devides at post border of scm and joins again
Facia around strap muscles superiorly attaches to hyoid bone and inf. Goes downward splits into 2 layers just abouve the sternum ant and post to sternum forms presternal space of burns
Carotid sheath- surrpunds IJV, CCD, X between superfial and pretracheal fasica
Pretracheal fasica- behind strap muscles facial anterior to trachea blends with cervical facial laterally trached doen it fuses fibrus pericardium
Prevertibral fascia – arise from vertbral spinal process lies on outer surface of muslces of back deep to trapizius muscle
Passes upward laterally
Enclosed by sperfical layer of deep fasica
Transverse colli, GAN EJV lie above this muscle
Lower part it covers lateral part of strap muscles
Occipital – at hyoid level
Sup.thy.-at lower part of carotid triangle
Trans cerval- lower end
Formed by lower border of mandible, scm and midline
and drains the lymph from the central part of lower lip,adjoining gums,floor of the mouth and tip of tongue
Duct passes over post border of mylohyoid muscle
Facial vein crosses over the gland while artery loops around gland to go between gland and muscle
Pass just above the hyoglossus muscle
l.a.- close to angle formed by 2 bellies
Infrahyoid muscles are arranged in two layers;
Superficial –sternohyoid and omohyoid
Deep-sternothyroid and thyrohyoid
Duct passes over post border of mylohyoid muscle
Facial vein crosses over the gland while artery loops around gland to go between gland and muscle
Pass just above the hyoglossus muscle
l.a.- close to angle formed by 2 bellies
Ligation-
In fact vagus is not a content of this triangle as it overlapped by SCM
Originates from jugular foramen -Crosses the IJV- Crosses lateral to the transverse process of the atlas- Descends obliquely in level II (forms Level IIa and Iib- Penetrates the deep surface of the SCM
- Exits posterior surface of SCM deep to Erb’s point
- Traverses the posterior triangle and lies in superficial cervical fascia and above the levator scapulae
- Enters the trapezius approx. 5 cm above the clavicle
Originates from jugular foramen -Crosses the IJV- Crosses lateral to the transverse process of the atlas- Descends obliquely in level II (forms Level IIa and Iib- Penetrates the deep surface of the SCM
- Exits posterior surface of SCM deep to Erb’s point
- Traverses the posterior triangle and lies in superficial cervical fascia and above the levator scapulae
- Enters the trapezius approx. 5 cm above the clavicle
C1 gives fibers to join hypo to form superior root of ansa
Fibers from c2 and c3 inferior root of ansa
Formed by union od anterior rami of 2,3,4 cevrical nerves .
C1 gives fibers to join hypo to form superior root of ansa
Fibers from c2 and c3 inferior root of ansa
Cutaneous branches derived from simple loop of 2,3,4
Lesser occipital- skin over side of neck behind ear
GAN- skin over parotid,almost all auricle, skin over mastoid
TC-turns around scm moves forvrds divdes in ascending descing branches supply skin of ant.portion of neck
SCN- divides in 3 sets- anterior,middle,lateral
Occipital artery emrges under cover of splinus capitus muscle and pentrate trapizius muscles