5. Anomalies of the thyroid gland
• Anomalies of shape
• Anomalies of position
– Lingual thyroid
– Intralingual thyroid
– Suprahyoid thyroid
– Infrahyoid thyroid
– Intrathoracic thyroid
• Ectopic thyroid tissue
6.
7. Congenital anomalies because of
persistence of cervical sinus
• Branchial cyst
• Branchial sinus
– External
– Internal
• Branchial/Cervical fistula
Arch syndrome
• Treacher Collins syndrome
(Mandibulo-facial dysostosis)
• Pierre Robin syndrome
• DiGeorge syndrome
8. Branchial
cleft fistula
% of
cases
External opening Internal opening Associated
structures
1st Work
Type I
5% Anterior and inferior
to tragus
External ear canal
or middle ear
VII
Work
Type II
Posterior to angle of
Mandible
Conchal bowl or
external ear cana
VII
2nd 90% Anterior border of
SCM
Tonsillar fossa between ICA
and ECA
XII
3rd and 4th <5% Anterior border of
sternocleidomastoid
muscle, lower neck
Piriform fossa
(3 rd superior and
4 th inferior to
superior laryngeal
nerve)
thyroid gland
17. •Platysma
• depressing the angle
of the mouth
• facial artery -
superior
suprascapular artery
- inferior
18. • MARGINAL MANDIBULAR :
• the sub-platysmal
• ligating the facial
vein(Hayes Martin maneuver)
• CERVICAL BRANCH:
• Platysma and corner of mouth
19. 1. Boundaries of compartments
2. Communicate infection or fluid to other regions of the
body
3. Guide to surgical dissection
4. Allow the neck structures to glide past one another
5. Supports the thyroid, lymph nodes and blood vessels
Surgical importance
20. Rule of Twos:
Two muscles crossing the neck
Two muscles above the hyoid
Two salivary glands
Two fascial compartments
Superficial layer SCM
Trapezius
22. Deep layer
This fascia divides to form the prevertebral fascia and the alar fascia.
Alar fascia- base of the skull to T2
Prevertebral fascia- entire length of the vertebral column.
28. Parapharyngeal Space
- Ant: ptreygomandibular raphe
- Post: prevertebral fascia
- Med: buccopharyngeal fascia
- Lat: investing layer of deep
cervical fascia
- Prestyloid compartment:
- Fat, CT, Inf alveolar, lingual,
auriculo.T nerve, Maxillary
artery
- Post-styloid compartment
- IX, XII, Carotid sheath
contents, Sympathetic
trunk
29. Displacement of the
parapharyngeal fat pad
1. Pre-styloid: deep lobe of
the parotid: postero-
medially
2. Post-styloid: carotid
body tumours or vagal
schwannomas, or
neuromas of the
sympathetic chain:
anteriorly
31. Retropharyngeal Space
Anteriorly: Buccopharyngeal fascia
Posteriorly: Alar fascia
Superiorly: Base of skull
Inferiorly: Second Thoracic Vertebra
Laterally: Carotid sheaths
Fused down the midline
Contents: Lymph Nodes
32. Danger Space
Anteriorly: Alar fascia
Posteriorly: Prevertebral fascia
Superiorly: Base of skull
Inferiorly: Diaphragm
Laterally: Carotid sheaths
Contents: loose areolar tissue
33. Prevertebral Space
Anteriorly: Prevertebral Fascia
Posteriorly: Bodies of vertebrae &
deep cervical musculature
Superoinferiorly: Entire length of
vertebral column
Spinal osteomyelitis and cord
compression
Extension of malignancy
35. Anterior Visceral/Pretracheal Space
• Bounded by Visceral division of middle layer
• Anteriorly: Infrahyoid strap muscles
• Posteriorly: Posterior wall of esophagus
• Superiorly: Thyroid cartilage
• Inferiorly: aortic arch and pericardium
Trachea
Thyroid gland
Anterior wall of Esophagus
36.
37. • Sternocleidomastoid
• Trapazius
• 2 heads- complex action
• Sup 1/3-occipital and posterior auricular
artery,
Mid 1/3-superior thyroid artery,
Inf 1/3-suprascapular artery.
• Sensation and proprioception -C2–4
• Torticolis
• Manti-gravity muscle of the shoulder;
• XI, Cervical plexus C3 C4
• Elevates, depresses and rotates the
scapula;
• Shoulder droop and a winged scapula
38. SPINAL ACCESSORY NERVE
Pass deep to the styloid process and
posterior belly of digastric muscle.
Courses across level II before penetrating
SCM
Posterior aspect of the SCM one
centimeter above Erb’s point,
All-important structures of the posterior
triangle are located caudal to the nerve.
Iatrogenic accessory nerve damage is
during level V neck dissection
Preserve all potential branches
39.
40. Supra-hyoid
Muscle
• Digastric
• Stylohyoid
• Mylohyoid
• Geniohyoid
posterior belly at the digastric ridge - landmark - depth of the facial nerve (exits the
stylomastoid foramen.)
42. • Prevertebral muscles
• Anterior prevertebral
muscles:
• Lateral prevertebral muscles
(scalene muscles):
phrenic – superficial to ant
scalene
2nd subclavian- post to scalenus
medius
Brachial plexus roots- b/w ant
and medius
Axillary sheath.
43. • Supplementary motor supply –
SCM & trapezius
• prevertebral muscles - longus
capitis, longus colli , scalene
muscles
• Ansa cervicalis:
• Phrenic nerve: deep to the
prevertebral fascia - runs
lateral to medial
CERVICAL PLEXUS NERVES:
44. • Lesser occipital nerve: skin
posterior to pinna upto
superior nuchal line
• Greater auricular nerve: neck
dissection & parotid surgery –
insensate lobule and
numbness over upper neck
and peri auricular skin
• Transverse cervical nerves:
sensory innervation- anterior
neck
• Supraclavicular nerves: skin till
sternoclavicular joint; anterior
chest wall; skin over deltoid
45. CERVICAL SYMPATHETIC TRUNK
• Runs on anterior surface of prevertebral
fascia, deep to carotid sheath
• Superior cervical ganglion: Symp: face,
neck
• Middle cervical ganglion: Parasymp:
thyroid, parathyroid
• Inferior cervical / Stellate ganglion
• Horner syndrome: i/l ptosis + meiosis +
anhydrosis of the facial skin
• Rare connections between the recurrent
laryngeal nerve and cervical sympathetic
trunk which, if divided, can result in
ptosis following thyroidectomy.
46. • Anterior and middle scalene muscles
• Inferior aspect of the posterior
triangle, deep to the prevertebral
fascia
BRACHIAL PLEXUS
47. 1 Submental
2 Submandibular
3 Parotid, superficial and deep
4 Posterior auricular
5 Occipital
6 Jugulodigastric
7 Jugulo-omohyoid
8 Supraclavicular
9 Deep cervical lymph chain
around the internal jugular
vein
10 Superficial cervical lymph
chains around external and
anterior jugular veins
CERVICAL LYMPHATICS
48. CERVICAL LYMPHATICS
• LEVEL IA:
• submental triangle, anterior floor of mouth,
lower lip, ventral tongue.
• LEVEL IB:
• submandibular triangle, lateral tongue, floor of
mouth, buccal cavity
• LEVEL II:
• oropharynx, oral cavity, nasopharynx,
hypopharynx and larynx, parotid gland.
XI nerve subdivides- IIa and IIb
• LEVEL III:
• lower areas of the oropharynx, hypopharynx,
larynx.
• LEVEL IV: hypopharynx and larynx,
49. • LEVEL V: all other nodal areas
• subdivided into Va and Vb by an imaginary
horizontal line at the level of the inferior
border of the cricoid cartilage
• LEVEL VI: The paratracheal, peri-thyroid
and precricoid (Delphian). thyroid, the
glottis or subglottic larynx, the apex of the
piriform fossa or the cervical oesophagus.
• LEVEL VII: superior mediastinal. thyroid,
subglottic, tracheal, cervical oesophageal
53. • Superior laryngeal nerve
• The internal laryngeal nerve-sensory
innervation-laryngeal, piriform fossa
mucosa, motor-interarytenoid muscle and
motor and sensory supply to the cervical
oesophagus and trachea.
• external laryngeal branch-motor-crico-
thyroid muscle
• The human communicating nerve (45%)
additional motor-thyroarytenoid muscle and
sensory-subglottic mucosa.
• Anastamose with RLN or directly supply
54. • Recurrent laryngeal nerve:
• Left RLN -ligamentum arteriosum
and arch of the aorta
• Right RLN-subclavian artery
• Non-recurrent course (1%)
• The relationship of the RLN and the
inferior thyroid artery is variable
but of great significance in thyroid
surgery as the nerve may run deep
to the artery, superficial to it or
between its branches
56. • Jolls triangle(sternothyrolaryngeal triangle)
Joll’s triangle
Lat- upper pole of thyroid + superior
thyroid vessels
med- midline
Sup- attachement of strap muscles +
deep investing layer of fascia to hyoid
Roof-strap muscle
57. BLOOD VESSELS
Common carotid artery:
• The vertebral, superior thyroid, inferior thyroid,
ascending pharyngeal or occipital arteries may arise
directly.
External carotid artery:
• ascending pharyngeal branch may arise
Internal carotid artery:
Subclavian artery:
59. • Internal jugular vein:
• Tributaries from the inferior
petrosal vein, the common facial
vein, the pharyngeal venous
system and the superior and
middle thyroid veins.
• Back flow - right atrium
• Facial veins:
• Face and oral cavity
• Plexus-submandibular triangle
• Superficial jugular veins:
• Anterior jugular vein and the
external jugular vein
• Subclavian vein
absence or malformation
microtia, hearing loss and facial asymmetry
Cleft- sinuses cyst and fistula
1. The relaxed skin tension lines of the neck run perpendicular to the fibres of the underlying platysma
2. anterior cervical skin- superior thyroid artery and the transverse cervical artery.
posterior cervical skin- occipital artery and the deep cervical branches
superior neck- occipital artery
anterior upper neck- submental and submandibular branches of the facial artery
inferior neck- transverse cervical and suprascapular branches of the subclavian artery via the thyrocervical trunk
3. Parotid lymph nodes are a common site for occult nodal involvement in skin cancers so parotidectomy should be considered for any neck dissection procedure for skin cancer.
The superficial cervical fascia underlies the skin of the head and neck in a continuous plane extending from the head down to the shoulders, axilla and thorax
Although the area contained within this fascial plane is not considered a deep neck space, it may serve as an additional barrier for containing oedema and pressure caused by infections in the underlying muscular and visceral compartments of the neck.
Superficial neck muscles
PLATYSMA: depressing the angle of the mouth, facial artery superiorly and the suprascapular artery inferiorly
Knowledge of the anatomy of cranial and cervical nerves in the neck is key to operating safely in the neck.
reliably located at point it crosses the mandible to leave the neck, running with the facial artery,
raising the flap in the sub-platysmal plane and locating the nerve before incising fascia inferior to it
ligating the facial vein inferior to the lower border of the submandibular gland and retracting the vein and fascia upwards
Surgical importance
Superficial layer courses from the posterior spinous processes of the vertebrae to its ant insertion into the sternum, hyoid, mandible and zygomatic arches.
It splits to envelop:
2 muscles that cross the neck:scm, and trapezius
2 muscles above the hyoid: ant belly of digastric and masseter
2 salivary glands: submand and parotid
2 fascial compartments: parotid and masticator spaces
This layer originates from the spinous processes of the vertebral column and spreads circumferentially around the neck, covering the sternocleidomastoid and trapezius muscles. In the midline, it attaches to the hyoid and continues superiorly to enclose the submandibular and parotid glands. Here it also covers the anterior bellies of the digastrics and the mylohyoid, thereby forming the floor of the submandibular space. At the mandible, the fascia splits into an internal layer, which covers the medial surface of the medial pterygoid to the skull base and an outer layer that covers the masseter and inserts on the zygomatic arch.
The middle layer of deep cervical fascia has two divisions:
The muscular division and the visceral division
Muscular division: surrounds the infrahyoid strap muscles (sternothyroid, sternohyoid, thyrohyoid)
The superior extent of the muscular division is the hyoid and thyroid cartilage, inferiorly it inserts on the sternum and clavicle.
Visceral division: envelops the trachea, pharynx, oesophagus and thyroid
The antero-superior extent of the visceral division is the hyoid and thyroid cartilage, while posteriorly this fascia covers the buccinator and the pharyngeal constrictors to the skull base—this portion is also called the buccopharyngeal fascia. Inferiorly, it continues into the mediastinum
The postero-superior aspect of the middle layer is also known as the buccopharyngeal fascia which forms the anterior boundary of the retropharyngeal space
The deep layer encloses the deep neck musculature and the vertebral column
originates from the spinous processes of the cervical vertebra and the ligamentum nuchae
The deep layer of deep cervical fascia divides as it reaches the longus colli muscle and anterior aspect of the vertebral bodies to form the prevertebral fascia and the alar fascia.
The alar fascia extends from the base of the skull to the second thoracic vertebra, where it joins the visceral fascia
The prevertebral fascia lies just anterior to the vertebral bodies and extends the entire length of the vertebral column.
Its formed from all three layers of the deep cervical fascia:
Anterolaterally by the Anteromedially by the r
Posteriorly, by the
• The anatomical triangles of the neck help to compartmentalize the anatomy of the neck.
• The travel from one triangle to another facilitates the concept of neck dissection.
• Sound knowledge of both triangles and contents converts two-dimensional knowledge into three-dimensional surgical reality.
2. The proximal superior thyroid artery, ascending pharyngeal artery, lingual artery, facial artery and occasionally the occipital artery may be found in this triangle.
SUBCLAVIAN TRIANGLE: branchial plexus, transverse cervical artery and suprascapular artery , domes of the pleura , supra-pleural fascia and the subclavian artery and vein
Submental space
Space enclosed between the mandible and the hyoid spanning from the mucosa of the floor of mouth till the superficial layer of deep cervical fascia
Divided by the myohyoid into two potential spaces
Communicate freely along the posterior aspect of mylohyoid
lateral pharyngeal or pharyngomaxillary space
Inverted pyramid shape from base of skull above till hyoid below
Boundaries:
-
+The styoid process divides the parapharyngeal space into a prestyloid muscular compartment and poststyloid neurovascular compartment
Prestyloid compartment:
Fat
Muscles
Lymph nodes
Connective tissue
Internal maxillary artery
Bounded by tonsillar fossa medially and medial pterygoid laterally
Post-styloid compartment
9, 10, 11, 12 cranial nerves
Ijv
Ica
Sympathetic trunk
The stylopharyngeal aponeurosis of Zuckerkandel and Testus separates the two compartments and prevents spread of infection from prestyloid to poststyloid space
Parapharyngeal infections have many sources because of the shear number of neighboring deep neck compartments, which include the submandibular, retropharyngeal, parotid, and masticator spaces
. The parapharyngeal space is a central connection for other deep neck spaces and as a result is a common site for deep neck abscess formation
3. Parapharyngeal space infection may occur directly or because of spread from the submandibular or peritonsillar spaces.
Tonsills
Trismus
The prevertebral fascia is the deep margin of neck dissec-
tion surgery, protecting the phrenic nerve and branchial
plexus which run deep to the fascia.
• Access and definitive surgery through the fascial planes
of neck is best facilitated with tissues under tension and
sharp dissection.
- Only deep space exclusively below the hyoid
STERNOCLEIDOMASTOID: origins as two separate heads, action is complex, superior third-occipital and posterior auricular artery, middle third-superior thyroid artery, inferior third-suprascapular artery. sensation and proprioception supplied by the ventral rami of C2–4
TRAPEZIUS: main anti-gravity muscle of the shoulder; elevates, depresses and rotates the scapula; shoulder droop and a winged scapula
Fibres from the anterior horn cells in the upper five or six segments of the cervical spinal cord pass intracranially through the foramen magnum to join fibres from the cranial root.
Care should be taken in posterior neck dissection to preserve all potential branches
Commonest cause of iatrogenic accessory nerve damage is during level V neck dissection
• The supra-hyoid and infra-hyoid muscles act antagonistically to elevate, depress or stabilize the hyoid for speech and swallowing
The origin of the posterior belly at the digastric ridge is a landmark for the depth of the facial nerve as it exits the stylomastoid foramen.
• The supra-hyoid and infra-hyoid muscles act antagonistically to elevate, depress or stabilize the hyoid for speech and swallowing
The origin of the posterior belly at the digastric ridge is a landmark for the depth of the facial nerve as it exits the stylomastoid foramen.
• phrenic nerve - superficial surface - anterior scalene muscle
the second part of subclavian artery - posterior to the scalenus anterior
The roots of the brachial plexus - scalenus anterior and scalenus medius
Branches of brachial plexus carry with them a layer of prevertebral fascia, which also encases the subclavian artery and becomes the axillary sheath.
• Access to lymphatic level II is facilitated by retraction of the digastric; when doing so it is important to remember that vital vascular structures lie immediately deep to the muscle.
lymphatics of level V receive drainage from all other nodal areas but are also a common location for metastatic involvement from nasopharyngeal or cutaneous scalp primary lesions.
is the space between
the longus colli muscle, the anterior scalene muscle as it
attaches to the C6 tubercle (Chassaignac’s tubercle) with
the subclavian vein as the inferior border.
sensory - laryngeal and piriform fossa mucosa, motor -interarytenoid muscle and motor and sensory supply to the cervical oesophagus and trachea.
Auricular branch
Carotid body branches
Pharyngeal branch
Superior laryngeal nerve
Cardiac branches
Recurrent laryngeal nerve
• It is important to remember the ICA has no branches in the neck and lies deep and lateral to the external carotid.
• Both the internal and external carotid arteries are intimately related to the glossopharyngeal nerve and the pharyngeal and laryngeal branches of the vagus nerve, as well as the vagus nerve itself, the hypoglossal nerve and the cervical sympathetic trunk.
Subclavian artery: first part of the subclavian artery lies deep to sternocleidomastoid and the strap muscles but may extend above the clavicle so is at risk during procedures in the supraclavicular fossa.
Drainage of the face and oral cavity is via the facial and lingual veins which then form a venous plexus in the submandibular triangle.
Drain into jugular vein.
Both the anterior jugular vein and the external jugular vein are part of a variable superficial venous system that drains the face and scalp. Drain into subclavian vein.
