Neck Flashcards
What is the common carotid artery?
Artery that provides the blood supply to the head and neck
Left and Right have different origins
Runs in the carotid sheath with the IJV + vagus N
Sits lateral to the pharynx
What is the gross anatomy of the carotid artery?
Runs in the carotid sheath, with the IJV laterally and vagus N between the two
IJV -> vagus N -> CCA
What is the origin and course of the common carotid artery?
Origin - Left - comes off the aortic arch. Right comes off the brachiocephalic trunk.
Courses up - behind sternocleidomastoid in the carotid sheath,
lateral to the trachea and thyroid and (superiorly) lateral to the pharynx
Splits into terminal branches ECA + ICA at the level of C3 / C4
What are the relations of the carotid artery?
runs in carotid sheath, vein, nerve, artery
anterior - sternocleidomastoid
posterior - prevertebral fascia, sympathetic ganglion, transverse process of C4-C6
medial - thyroid, trachea, pharynx
lateral - Vagus N, IJV, SCM (anterolateral)
What are the anatomical variants associated with the carotid artery?
can birfurcate earlier into ICA + ECA
bovine arch -
left CCA / left subclavian A have common origins
What is the external carotid artery?
It is a branch of the common carotid artery
Supplies the structures to the face and neck
Where does the external carotid artery sit?
90 percent of the time, the ICA will sit posteromedially to the ECA
Styloglossus and stylopharyngeus will divide the ICA and ECA
What is the gross anatomy of the external carotid artery?
It is distinguishable from the ICA as it has branches, while the ICA does not have branches. The ICA courses posteromedially.
origin of the external carotid artery is the bifurcation at C3-C4.
ascends in the neck, lateral to the larynx and pharynx
Ends as the maxillary artery, as superficial temporal artery in the parotid
What are the branches of the external carotid artery?
T - superior thyroid artery
P - ascending pharyngeal artery
L - lingual artery
F - facial artery
O - occipital artery
P - posterior auricular artery
T - superficial temporal artery
M - maxillary artery
What are the relations of the external carotid artery?
Terminal division of ECA is in the parotid gland as maxillary artery , superficial parotid artery
Medial - internal carotid artery (posteromedial), pharynx, larynx
Anterior - sternocleidomastoid
Lateral - sternocleidomastoid
Inferior - Common carotid bifurcation is at C3- C4
Styloglossus and stylopharyngeus will divide the ICA and ECA into two parts.
What are the common anatomical variants associated with the external carotid artery?
All branches of the external carotid artery can come off the common carotid.
Can have common trunks of:
- lingual and facial - linguofacial trunk
- superior thyroid and lingual artery - thyrolingual trunk
- superior thyroid and lingual and facial - thyrolingualfacial trunk
- occipital and posterior auricular - occipitoauricular trunk
What is the gross anatomy and function of the cervical portion of the internal carotid artery?
- runs in the carotid sheath with the internal jugular vein and the vagus N
- divided from the external carotid artery by the stylopharyngeus and styloglossus
- Differentiate between the ICA and ECA as the ICA does not have any branches in the neck, the ICA starts more lateral and then moves posteromedial, divided from ECA by muscles of styloid process
What is the origin, course, and termination of the internal carotid artery?
Begins at the common carotid bifurcation - C3/C4.
ascends in neck lateral to pharynx
Runs in the carotid sheath, will be postero - vagus, medial - IJV both from the jugular foramen
terminates in the carotid canal in the petrous temporal bone
no branches
supplies the brain
What are the relations of the internal carotid artery?
anterior: ECA - anterolateral
sternocleidomastoid
Posterior:
sympathetic trunk
transverse processes of C4-C1
Superior:
carotid canal (for ICA)
Jugular foramen (for IJV and vagus)
Inferior:
bifurcation at C3-C4
Medial:
pharynx and larynx
Lateral:
Styloglossus and stylopharyngeus
What is the thyroid gland?
It is a midline neck gland
Single endocrine gland
Where does the thyroid gland sit?
Sits in the visceral space of the neck
Enveloped in deep cervical fascia
From C5-T1, infront of the 3 tracheal rings
What is the gross anatomy of the thyroid gland?
Is made of an superior + inferior pole
2 lobes joined by an isthmus
Parathyroid glands posterior
How many parathyroid glands are there?
4 parathyroid glands
However can be less than 3 or greater than 4
Found in different positions
What are the relations to the thyroid gland?
Anterior: strap muscles; sternohyoid, sternothyroid
Posterior: trachea, oesophagus, tracheooesophageal groove, recurrent laryngeal N, parathyroid glands
Lateral: common carotid A, internal jugular vein
What is the arterial supply of the thyroid gland?
Superior thyroid artery (First branch of the external carotid artery, with the superior laryngeal N)
Inferior thyroid artery (thyrocervical trunk, w recurrent laryngeal N)
What is the venous drainage of the thyroid gland?
Superior thyroid vein (drains to IJV)
Middle thyroid vein (drains to IJV)
Inferior thyroid vein (drains to BCV)
What is the lymphatic drainage of the thyroid gland?
first drains to perithyroid lymph nodes, then to level 6 lymph nodes
What is the nerve supply to the thyroid gland?
Superior laryngeal N - related superior thyroid A
Inferior laryngeal N - related to inferior thyroid A
What are the muscles/ligaments / fascia involved with the thyroid?
sternohyoid, sternothyroid
sternocleidomastoid
is all sheathed in deep cervical fascia
What are the anatomical variants associated the thyroid?
thyroid ima
pyramidal lobe
thyroglossal duct cyst
ectopic thyroid tissue
lingual thyroid
thyroid lobe hemiagenesis
What are the parathyroid glands?
paired endocrine glands, involved in calcium homeostasis with the thyroid gland
Where do the parathyroid glands sit?
In the tracheooesophageal groove
In the visceral space of the neck in the tracheooesohgaeal groove
posterior to the thyroid (can be intra capsular or extra capsular)
What is the gross anatomy of the parathyroid gland?
usually two pairs - superior pair and inferior pair
bean shaped
variation in terms of location, from carotid bifurcation down to anterior mediastinum -
BUT USUALLY SIT posterior to thyroid in the tracheooesphageal groove
What are the relations to the parathyroid gland?
Anterior - trachea, thyroid
Posterior - oesphagus
superior - cricopharyngeus, inferior constrictor
inferior - anterior mediastinum, cervical oesophagus
Medial - tracheooesophageal groove (with recurrent laryngeal N and paratracheal lymph nodes)
Lateral - common carotid artery
What is the arterial supply of the parathyroid artery?
Superior thyroid artery (for superior pair) - comes off external carotid artery
Inferior thyroid artery (for inferior pair) - thyrocervical trunk
What is the venous drainage of the parathyroid gland?
Superior / middle / inferior thyroid veins
What is the lymphatic drainage of the parathyroid glands?
Perithyroid veins - level 6 lymph nodes
What is the nerve supply of the parathyroid gland?
superior laryngeal N (with superior thyroid artery)
recurrent laryngeal N (with inferior thyroid artery) - also in tracheooesophageal groove
What are the anatomical variants associated with the parathyroid gland?
ectopic parathyroid
greater than > 4 glands
Less than < 3 glands
can be intracapsular vs extracapsular
postition - can be from carotid bifurcation to anterior mediastinum
What is the sternocleidomastoid muscle?
It is responsible for dividing the neck into anterior and posterior triangles of the neck
What is the motion of the sternocleidomastoid?
To allow for lateral flexion + forward flexion of the neck
What is the gross anatomy of the sternocleidomastoid?
Has two heads which meld into one insertion
Sternal head
Clavicular head
Between two heads of sternocleidomastoid can access the IJV
Insert onto the mastoid process of the temporal bone
What is the nerve supply of the sternocleidomastoid?
Cranial N XI - accessory N
What is the action of the sternocleidomastoid?
Lateral flexion, forward flexion
What are the relations involved with the sternocleidomastoid?
is the anterior border of the posterior triangle
is the posterior border of the anterior triangle
SCM divides the internal and external jugular veins
Cervical plexus comes out behind SCM
What are the relations involved with the sternocleidomastoid?
Anterior - external jugular vein
platysma
Posterior - internal jugular vein
cervical plexus - transverse cervical N, greater auricular N, accessory N, dorsal scapular N
Inferior - clavicle
Medial - STRAP muscles, ICA/ECA/CCA, vagus N, IJV
Superior - mastoid process of temporal bone, mandible
What is the sternocleidomastoid arterial supply?
superior thyroid artrery
What is the nerve supply of sternocleidomastoid?
the accessory N
What are the borders of the posterior triangle of the neck?
anterior border of trapezius
posterior border of sternocleidomastoid
middle 1/3 of clavicle
What is the roof of the posterior triangle?
investing fascia
platysma
external jugular vein
spinal accessory nerve crosses obliquely
What is the floor of the posterior triangle?
prevertebral fascia - covers scalenus anterior, medius, posterior
levator scapulae, splenius
fascia forms axillary sheath
subclavian artery
branches of brachial plexus + cervical plexus
What are the contents of the posterior triangle of the neck?
Arteries - occipital, superficial cervical, suprascapular, 3rd part of the subclavian A
Veins - suprascapular, external jugular, transverse cervical
Nerve - branches of cervical plexus: lesser occipital N, greater auricular N, transverse nerve of neck, supraclavicular N, spinal accessory N, supraclavicular branches of the brachial plexus: dorsal scapular N, long thoracic N, nerve to subclavius
Muscle - omohyoid with its sling; divides the triangle into upper and lower
Lymph nodes - occipital nodes, supraclavicular nodes
What is the oesophagus?
Muscular tube from oropharynx down to the stomach
Function is to propel food bolus down via peristalsis to stomach
What are the parts of the oesophagus?
Cervical - from cricopharygngeus C6 to superior thoracic aperture T1
Thoracic - superior thoracic aperture T1 to oesophageal hiatus in diagphram T10
Abdominal - from oesophageal hiatus of diagphram to GOJ
What are the narrowings of the oesophagus?
cricopharyngeus (C6)
Arch of Aorta at T3 + left main bronchus at T4
Oesophageal hiatus of diagphram at T10
What is the course of the oesophagus?
Continuous with oropharynx + cricopharyngeus
Courses through the posterior mediastinum
Through oesophageal hiatus, Blends with cardia / GOJ of stomach
What is the arterial supply of the oesophagus?
Cervical - inferior thyroid artery
Thoracic - oesophageal branches of aorta
Abdominal - left gastric artery (oesophageal branches)
What is the venous drainage of oesophagus?
Cervical - inferior thyroid vein (to brachiocephalic vein)
thoracic - to azygos vein
abdominal - left gastric vein (to portal vein)
What is the lymphatic drainage of the oesophagus?
Cervical - To deep cervical chain
Thoracic - to posterior mediastinal nodes
Abdominal - to left gastric + coeliac nodes
What is the nerve supply of the oesophagus?
upper 1/3 - recurrent laryngeal N
lower 2/3 - oesophageal plexus (from vagus N)
Left vagus becomes anterior vagal plexus
Right vagus becomes posterior vagal plexus
What are the muscles involved with the oesophagus?
the diagphramatic crus - left and right
What is the anatomical variation associated with the oesophagus?
oesophageal atresia
oesophageal bronchus
abberant right subclavian artery
What is the nasopharynx?
Area posterior to the choanae
But before lower limit of soft palate
Links the nasal cavity to the oropharynx
What is the gross anatomy / boundaries of the nasopharynx?
Anterior:
Nasopharynx
Posterior:
adenoids
pharyngeal constrictor
longus capiitis/collis, clivus of occiput, C1/C2
Lateral:
torous tubarius (cartilaginous top of eustachian tube)
tensor veli palatini
lateral pharyngeal recess
parapharyngeal space
Superior:
sphenoid sinus
Inferior:
soft palate
oropharynx
What are the contents of the nasopharynx?
Adenoid
Torus tubarius
lateral pharyngeal recess
What are the relations of the nasopharynx?
Laterally - parapharyngeal space
Eustachian tube - torus tubarius opens in the lateral nasopharynx
What is the arterial supply of the nasopharynx?
Pharyngeal A
Sphenopalatine A
Greater palatine A (from maxillary)
What is the venous drainage of the nasopharynx?
ptyergoid venous plexus
What is the lymphatic drainage of the nasopharynx?
The adenoids (part of waldyers ring)
Drains to level 2 nodes
What is the nerve supply of the nasopharynx?
The nasopharynx is innervated by the pharyngeal plexus except for tensor veli palatini (CN V)
What are the muscles / ligaments / fascia involved with the nasopharynx?
tensor veli palatini
Levator veli palatini
- both accompany eustachian tube - tensor anterior, levator posterior
Both will raise the soft palate during swallowing, stopping reflux of food in the nose
What is the larynx?
The entrance to the airway
Protects the airway and produces voice
What is the gross anatomy of the larynx?
1 bone
4 cartilages
Hyoid bone - U shaped, greater cornu, lesser cornu, joined to thyroid by cricothyroid membrane
What is the gross anatomy of the epiglottis?
epiglottis
leaf shaped
divided into suprahyoid and infrahyoid
What is the gross anatomy of the thyroid cartilage?
thyroid cartilage
shield shaped
2 lamina - each lamina has a superior horn / cornu and inferior horn/ cornu
oblique attachment - (this is where muscles attach), cricothyroid ligament joins the cricoid and thyroid anteriorly
*it is the aim in emergency tracheostomy
What is the gross anatomy of the arytenoid cartilage?
pyramid shaped
attachment of vocal ligament
What are the key sinuses / recesses of the larynx?
Vallecula - between the epiglottis and hyoid bone
Vestibular fold
Ventricle / sinus of larynx (between vestibule and true vocal fold)
piriform sinus - either side of laryngeal recess
What is the course of the larynx?
Continuous superiorly with oropharynx, and inferiorly with trachea
What are the relations of the larynx?
Anterior - thyroid gland
Lateral - great vessels of the neck, CCA/ICA/ECA, IJV
Posterior - pharynx/oesophagus, tracheooesophageal groove (RLN, PT, LN)
What is the arterial supply of the larynx?
Superior thyroid A - superior laryngeal A (with superior laryngeal N)
Inferior thyroid A - inferior laryngeal A (with recurrent laryngeal N)
What is the venous drainage of the larynx?
Superior laryngeal vein - drains to superior thyroid vein
Inferior laryngeal vein - drains to inferior thyroid vein
What is the lymphatic drainage of the larynx?
level 6 lymph nodes
What is the nerve supply of the larynx?
Superior laryngeal N + Recurrent laryngeal N - both come off vagus N
What does the superior laryngeal N supply in the larynx?
Sensory - all sensation above the vocal cords (internal branch of superior laryngeal N)
Motor - cricothyroid only (external branch of superior laryngeal N)
What does the recurrent laryngeal N supply in the larynx?
Sensory - sensation below the vocal cords
Motor - all intrinsic muscles of the larynx except cricothyroid
Including the posterior cricoarytenoid - which is the adductor of the vocal cords
What are the muscles / ligaments / fascia involved with the larynx?
vocal ligaments - true cords
vestibular folds - false cords
What is the most key muscle of the larynx?
posterior cricoarytenoid
This is a key muscle in the larynx
Adductor of the vocal folds
If it gets damaged during neck surgery e.g. thyroidectomy bilaterally - bad!
What is the anatomical variant associated with the larynx?
laryngomalacia - immature cartilage which collapses with inspiration, causing stridor
What is the mucosa of the larynx?
pseudostratified ciliated columnar
Mucus glands in the sinus
What is the lymphatic drainage of the larynx?
above cords: upper deep cervical nodes
below cords: lower deep cervical nodes
What are the pharyngeal constrictor muscles?
They are muscle slings which are superior and continuous with the oesophagus
Function is to deliver a food bolus to the oesophagus
What is the gross anatomy of the pharyngeal constrictor muscles?
3 slings - designed to interdigitate with the next
What is the origin and insertion of the superior pharyngeal constrictor?
origin:
ptyergoid hamulus
ptyergomandibular raphe
insertion:
pharyngeal raphe
middle constrictor
What is the origin and insertion of the middle pharyngeal constrictor?
origin:
greater cornu of hyoid
stylohyoid ligament
insertion:
pharyngeal raphe + inferior constrictor
What is the origin and insertion of the inferior pharyngeal constrictor?
origin:
oblique line of thyroid, cricoid (fibrous arch)
insertion:
pharyngeal raphe
cricopharyngeus
What is the course of the pharyngeal constrictor muscles?
Continuous with the oropharynx superiorly
Continuous with cricopharyngeus and oesophagus inferiorly
What are the relations of the pharyngeal constrictor muscles?
anterior - nasopharynx, oropharynx, laryngopharynx
posterior - retropharyngeal fascia, prevertebral space
lateral - CCA, ICA, ECA, vagus, IJV in carotid sheath
What is the arterial supply of the pharyngeal constrictor muscles?
ascending pharyngeal A (comes off the ECA)
What is the venous drainage of the pharyngeal constrictor muscles?
drain to superior, middle and thyroid veins
and eventually to IJV
What is the lymphatic drainage to the pharyngeal constrictor muscles?
deep cervical -> drain to level 3 + 4 nodes
What is the nerve supply to the pharyngeal constrictor muscles?
vagus / pharyngeal plexus
superior laryngeal nerve - external branch
What is the muscles / ligaments / fascia involved with the pharyngeal constrictor muscles?
posterior pharyngeal raphe
has contributions from all the constrictor muscles
What is the vagus N?
It is the 10th cranial N.
Is responsible for the parasympathetic supply of the body
What is the function of the vagus N?
Responsible for parasympathetic supply to GIT + heart
Motor + Sensory supply to pharynx (pharyngeal constrictors) + larynx (RLN, SLN)
Where does the vagus nerve sit?
In the posterolateral medulla -> perimedullar cistern-> jugular foramen -> carotid sheath -> posterior mediastinum -> oesophageal hiatus -> anterior + posterior vagal plexus
What is the origin, course and termination of the vagus N?
Origin: medulla (posterolateral medulla)
Though premedullar cistern / pre pontine cistern
jugular foramen (with internal jugular vein)
In carotid sheath - ICA medial, IJV lateral
- anterior scalene is posterior
Anterior to subclavian A
- left vagus goes lateral to aortic arch and gives off RLN which hooks under
- right vagus goes anterior to right subclavian and gives off RLN which hooks under
- Both then travel to midline, and course posterior to lung hilum
- Wraps around esophagus
-travels through oesophageal hiatus (with left gastric A+V)
- terminate as anterior + posterior vagal trunk
What does the vagus N supply?
larynx
pharynx
oesophagus
GIT parasympathetics
What are the branches of the vagus N?
Superior laryngeal N
- sensation above vocal folds
- only supplies cricothyroid, sup-mid-inf constrictors
Recurrent laryngeal N
- sensation below vocal folds
- all muscles of the larynx except cricothyroid
What are the core relations of the vagus N?
In the head - runs through the jugular foramen with internal jugular vein
In carotid sheath - runs with internal carotid artery + internal jugular vein
In the neck, carotid sheath - runs anterior to anterior scalene
In superior thoracic aperture -
- Right goes anterior to R subclavian A
- Right RLN will hook under R subclavian A to enter tracheooesophageal groove
- left goes lateral to aortic arch
- left RLN hooks under aortic arch, lateral to ligamentum arteriosum, and enters tracheooesophageal groove
Mediastinum will be posterior to pulmonary hilum
- phrenic N is the N which runs anterior to lung hilum
At oesophageal hiatus, vagal trunks travel through T10 with LEFT GASTRIC A + VEIN
Left vagus - anterior trunk, Right vagus - posterior trunk
What is the phrenic nerve?
It is the motor and sensory supply to the diagphram
What is the origin, course and termination of the phrenic N?
Origin: C3, C4, C5
Course: descends on anterior scalene, all relations of left phrenic are arterial, right phrenic are venous
Terminates - left pierces the hemidiapghram independently
RIGHT PHRENIC TRAVELS THROUGH VENA CAVAL FORAMEN AT T8
What are the relations of the left phrenic N?
anterior to subclavian A
lateral to aortic arch
lateral to left auricle
anterior to lung hilum
lateral to left ventricle
pierces dome of left diagphram (through entire course, runs with pericardiophrenic A + V)
What are the relations of the right phrenic N?
posterior to subclavian V
lateral to superior vena cava
lateral to right atrium
anterior to lung hilum
lateral to right ventricle
passes through vena caval foramen of diaphgram at T8 (through entire course runs with pericardiophrenic A + V)
What does the phrenic N supply?
The diaphragm - motor function and sensory function
Mediastinal pleura
Pericardium
Where are the level 1 lymph nodes of the neck?
Under mylohyoid: submental (1A) + submandibular (1B)
What are the level 2 lymph nodes of the neck?
internal jugular chain - deep cervical
adjacent to posterior belly of digastric / upper 1/3 of sternocleidomastoid
What are the level 3 lymph nodes of the neck?
internal jugular chain
related to middle 1/3 of sternocleidomastoid
What / where are the level 4 lymph nodes of the neck?
internal jugular chain
related to lower 1/3 of sternocleidomastoid
Where / what are the level 5 lymph nodes of the neck?
Posterior triangle / spinal accessory nodes
Runs with spinal accessory N
5A (upper) + 5B (lower)
What / where are the level 6 lymph nodes of the neck?
pre tracheal lymph nodes
delphian node
What / where is the level 7 lymph nodes of the neck?
Superior mediastinal nodes
Adjacent to the carotid arteries
What are the additional lymph nodes involved in the spaces of the neck?
Parotid lymph nodes (in the parotid space)
Retropharyngeal lymph nodes (in retropharyngeal space, above hyoid)
Supraclavicular lymph node (final common channel of lymphatic pathway) Contains virchows node on the left side
What are the boundaries of the anterior triangle?
anterior border of the sternocleidomastoid
Midline
What are the subdivisions in the anterior triangle?
Carotid
Posterior belly of digastric
Superior belly of omohyoid
Anterior border of sternomastoid
Roof is skin - superficial fascia
Floor is pretracheal fascia (over larynx + pharynx)
Deep to posterior digastric belly / submandibular / submental / muscular
What are the contents of the anterior triangle?
Carotid sheath
Common internal/ external carotid sinus
Internal jugular vein / upper and deep nodes
Vagus N
External laryngeal N
Recurrent laryngeal N
Accessory N
Ansa cervicalis
Sympathetic trunk
What are the contents of the anterior triangle deep to the posterior belly of digastric?
Deep to digastric posterior belly
- large NV bundle which runs between head + neck
- Structures include - carotid sheath, internal + external carotid arteries, ascending pharyngeal artery, internal jugular vein
Nerves
- vagus N
- superior layrngeal N
- accessory N
- hypoglossal N
- sympathetic trunk
What are the boundaries in the submandibular triangle?
Contained within the anterior triangle of the neck
Boundaries:
Lower border of mandible
anterior border of digastric
posterior border of digastric
floor - styloglossus, omohyoid
What are the contents of the submandibular triangle?
superficial part of submandibular gland
facial vessels
submandibular lymph node
hypoglossal N
N to mylohyoid
What are the boundaries of the submental triangle?
Located in the anterior triangle of the neck
Boundaries
Midline - body of hyoid bone
Anterior belly of digastric
Floor is mylohyoid
Roof is skin, superficial fascia
What are the contents of the submental triangle?
submental lymph nodes
anterior jugular vein origins
What are the boundaries of the muscular triangle?
Located within the anterior triangle
Boundaries:
C6 level midline
Roof is skin/ fascia
Superior belly omohyoid
Floor is larynx
What is contained in the muscular triangle?
infrahyoid muscles
