Sievert-Superficial & Deep Neck Flashcards
In cervical cross section, all of the muscle are covered in cervical investing fascia except for one muscle. What is this exception?
the platysma muscle. It is more superficial than the muscles in the investing fascia.
it is superficial to the cervical investing fascia & deep to the superficial fascia.
There are four compartments in cervical cross section. What are they?
- Cervical Investing Fascia Compartment
- Prevertebral Fascia Compartment
- Pretracheal Fascia Compartment
- Carotid Sheath
So almost everything on cervical cross section is deep to the cervical investing fascia…but what are the 2 muscles that are directly invested in cervical investing fascia? This helps to form the ____ triangle.
trapezius
sternocleidomastoid
**posterior triangle
What are the 2 ridges on the temporal region of the skull?
- temporalis attachment
- the second one above that is the cervical investing fascia attachment.
The cervical investing fascia has an extensive origin & insertion. Describe it roughly.
clavicle–>zygomatic arch & superior temporal line
Which muscles does the pre vertebral fascia surround? This fascia splits into which 2 layers? Where does it split?
It surrounds the muscles that surround the vertebrae.
Fascia splits into prevertebral layer & alar layer near the anterior portion of the vertebral body.
What is the retropharyngeal space & why is it considered dangerous? Where does it run? What is its fcn?
- *this is the space b/w the alar & pre vertebral layers of the pre vertebral fascia
- *considered dangerous b/c of possibility of spread of infection
- *runs b/w base of skull to thorax (superior mediastinum)
- *normal fcn: allows for movement of the esophagus & larynx during swallowing
Of the cervical compartments…which is considered a visceral compartment? What is found there?
the compartment covered in pre tracheal fascia.
in here is the larynx & trachea, the esophagus, thyroid gland, and strap muscles
What is the name of the fascia directly posterior to the esophagus?
buccopharyngeal fascia
Which fascia layers make up the carotid sheath? What is contained in here?
a bunch of different fascia layers!! cervical investing fascia, prevertebral, & pretracheal fascia! contains: common carotid artery & internal carotid artery internal jugular vein CN10 Branches of CN9 Deep Nodes
How might you get an infection in the retropharyngeal space?
perhaps by falling w/ a popsicle stick in your mouth–puncture the pharynx thru the buccopharyngeal fascia.
Where is the sympathetic trunk found on cross section?
in the retropharyngeal space.
What are the superficial veins of the neck? Are they easy to puncture?
They are easy to puncture b/c they are so superficial–esp the external jugular vein.
- Facial Vein
- External Jugular Vein
- Anterior Jugular Vein
- Internal Jugular Vein
T/F There are a lot of anastomoses b/w the superficial veins of the neck.
TRUE
Where does the facial vein mainly drain?
mainly into the internal jugular vein
Which of the superficial veins empty into the subclavian vein?
All of them pretty much.
Def the facial, external jugular, and internal jugular. Sometimes the anterior jugular. Sometimes the anterior jugular vein empties into the external jugular vein.
What happens if you nick a superficial neck vein?
it is bad b/c the CT that they are invested in keeps them open even after they are punctured. This allows air into them & the air will enter the heart & cause immediate block of blood flow.
What are the main triangles of the neck?
Posterior & Anterior
What are the borders of the posterior triangle?
sternocleidomastoid (anterior)
trapezius (posterior)
clavicle (inferior)
What are the important nerves that you can find in the posterior triangle?
- spinal accessory nerve (CN11) on its way to the trapezius. (True spinal part of CN11. embedded in investing fascia & tortuous course)
- Cervical plexus nerves
- Roots of the brachial plexus
The cervical plexus nerves emit behind which muscle?
the sternocleidomastoid muscle
There is the true spinal part of CN11 & the _______ part, which courses w/ CN____.
cranial part which courses w/ CN10
Which muscles are found in the posterior triangle of the neck?
Scalenes (anterior, middle, posterior)
Omohyoid muscle courses across (not sure if technically a part of it)
levator scapulae muscle
splenius cervicis muscle
(borders-sternocleidomastoid & trapezius)
Which arteries are found in the posterior triangle of the neck?
Subclavian Artery
- thyrocervical trunk (off the subclavian)
- -suprascapular
- -transverse cervical (both branches of thyrocervical trunk)
A knife wound to the posterior triangle of the neck could cause a severe hemorrhage, esp if it caught the ______ artery.
subclavian artery
Where can you see the roots of the brachial plexus in the posterior triangle?
b/w the anterior & middle scalene muscles.
Which vein is seen in the posterior triangle?
the external jugular vein
The anterior triangle of the neck can actually be subdivided into 4 sub triangles. What are they? Which of these is the most important? Which of these are filled in with muscles?
Submandibular Triangle
Submental Triangle-filled with muscle
Muscular Triangle-filled with muscle
Carotid Triangle-most important!!
What are the borders of the anterior triangle?
Sternocleidomastoid (lateral) Anterior Midline (medial) Mandible (superior)
The carotid sheath & its contents are found in which triangle?
surprise surprise…the carotid triangle.
Aside from the carotid sheath & its contents, what other important structures are found in the anterior triangle?
ansa cervicalis-in carotid triangle too
thyroid gland
muscles (of larynx, hyoid bone)
viscera
T/F There are 2 triangles of the anterior triangle bilaterally, making 4 total.
False. There are 4 bilaterally of the anterior triangle.
What are the borders of the carotid triangle?
posterior belly of the digastric muscle (superior)
anterior border of the sternocleidomastoid muscle (posterior)
superior belly of the omohyoid muscle (anterior)
What are the boundaries of the submandibular triangle? Why is this triangle sort of important?
anterior & posterior bellies of the digastric muscle
mandible
**important b/c there is the submandibular gland here.
Aside from the brachial plexus, what else do you find coming out b/w the anterior & middle scalenes?
the subclavian artery pops off posterior to omohyoid belly.
What happens in anterior scalene syndrome? Where does this happen in relation to the 1st rib?
this occurs w/ compression of brachial plexus or subclavian artery b/w the anterior & middle scalene.
this can happen if the tone of these muscles is increased or there is randomly a cervical rib.
this happens superior to the 1st rib.
may notice numbness in the periphery
What happens in thoracic outlet syndrome? Where does this happen in relation to the 1st rib?
this happens with compression of your subclavian vein or other structures b/w your clavicle & 1st rib
may notice numbness in the periphery
The nerves of the cervical plexus begin in which triangle? They peek out around which muscle? What are they invested in?
begin in the posterior triangle
they peek out around the sternocleidomastoid muscle
they are invested in fascia
Compare & contrast the greater & lesser occipital nerves.
Greater occipital nerve: goes thru the sub occipital triangle; dorsal ramus of a spinal nerve
Lesser occipital nerve: gives cutaneous innervation to the back of the head & part of the ear & starts posterior laterally. Root of cervical plexus. Ventral ramus of spinal nerve.
What are the 4 branches of the cervical plexus that we will talk about–that peek out over the sternocleidomastoid muscle?
- Lesser Occipital Nerve
- Greater Auricular Nerve
- Transverse Cervical Nerve
- Supraclavicular Nerve
What’s the course & innervation for the greater auricular nerve?
comes out from under the sternocleidomastoid & then courses over it.
mainly gives cutaneous innervation to the ear
What’s the course & innervation of the transverse cervical nerve?
comes out from underneath the sternocleidomastoid muscle & courses over the SCM (but lower than 1st & 2nd cervical plexus nerves)…goes to the neck
gives cutaneous innervation to anterior cervical neck region
What’s the course & innervation of the supraclavicular nerve?
the supraclavicular comes out from behind the SCM & courses down. It branches into the internal, medial, & lateral branches.
it supplies cutaneous innervation to clavicle & part of the shoulder
T/F Anesthesiologists do local blocks that affect different branches of the cervical plexus.
True.
The cervical plexus is made up of C_ –>C _?
C1-C4
Describe the contribution of C1 to the cervical plexus.
It gives a little contribution to the bulk of the plexus, but not much & not sensory. It mainly combines with CN12 for a while to give a motor component to geniohyoid & thyrohyoid muscles. it also gives off a branch that forms the superior limb of the ansa cervicalis.
What is the sensory contribution of C2 in the cervical plexus?
C2 combines with C3 & goes up to give off the lesser occipital & greater auricular nerves
What is the sensory contribution of C3 in the cervical plexus?
C3 combines with C2 to go up & give off the lesser occipital & greater auricular nerves.
It also goes straight across to give off the transverse cervical nerve.
It also combines with C4 to give off supraclavicular branch that goes down!
What a busy guy!!
What is the sensory contribution of C4 in the cervical plexus?
C4 combines with C3 to give off the supraclavicular nerve.
What gives the motor contributions from the cervical plexus that make up the phrenic nerve?
C3, C4, a little C5
they form the phrenic & this courses down to innervate the diaphragm.
Which triangle of the neck is the phrenic nerve a part of?
It isn’t a part of any triangle! It courses right behind the SCM & on top of the anterior scalene.
What do you have to be careful of when doing an anesthetic injection in the cervical plexus?
you have to be careful of the phrenic nerve…otherwise you could paralyze a hemi-diaphragm.
The ansa cervicalis is a motor loop from the cervical plexus. It has an inferior & superior limb. What’s the deal with this thing?
Superior Limb: From C1 (after it traveled with CN12)
Inferior Limb: From C2 & C3
Its fibers innervate the hyoid muscles (like sternohyoid, omohyoid).
What does the ansa cervicalis lie on top of? What does it wrap around?
Lies on top of the carotid sheath
Wraps around the internal jugular vein.
We know that the genohyoid muscle is innervated by contributions from C1, after it traveled on CN12 for a bit. What’s the deal with this muscle?
This muscle is seen above the hyoid bone. Connects the chin to the hyoid bone.
We know that the thyrohyoid muscle is innervated by contributions from C1, after it traveled on CN12 for a bit. What’s the deal with this muscle?
This muscle is seen below the hyoid bone. Connects the hyoid bone to the thyroid gland.
Which areas of the body can refer pain to the shoulder? Why does this make sense?
diaphragm
liver
gallbladder
**these are all areas that can affect the peritoneum on the undersurface of the diaphragm-an area innervated by the phrenic nerve.
**phrenic nerve–dorsal horns of C3, C4, C5
**supraclavicular nerve–dorsal horns of C3, C4–skin over the shoulder.
Therefore, pain in these areas becomes pain in the shoulder b/c of overlap of fibers in the dorsal horns.
When you are doing a parotid endarterectomy you have to be careful about which nerve? What would happen if you did damage it?
CN12! innervates intrinsic & extrinsic tongue muscles
trouble speaking b/c tongue muscles on one side would be damaged
dysarthria
lower motor neuron syndrome.
What do the intrinsic muscles of the tongue allow you to do?
allow you to flatten & roll your tongue
You could also get dysarthria from damage to what other nerves besides CN12?
CN7, Recurrent Laryngeal, maybe some others
What is the difference b/w dysarthria & aphagia?
dysarthria–is difficulty speaking b/c of muscle problem
aphagia–inability to speak b/c of a brain problem.
What does CN12 innervate?
both the extrinsic & intrinsic tongue muscles
anything with glossal in its muscular name except for palatoglossus.
What innervates palatoglossus & most of the palate muscles?
CN10
**but CN10 doesn’t innervate tensor veil palatini b/c this is innervated by CN5.
Describe the course of CN12.
Starts out in the hypoglossal nucleus (from post-otic somites in the medulla) & then goes thru the hypoglossal canal.
Does the hyoid bone articulate with other bones?
Nope. It is free floating. there are muscles above & below it.
The muscles above & below the hyoid bone help it to do what?
help it to elevate & depress in vocalization & swallowing
When is the greater horn of the hyoid bone palpable?
only when the hyoid bone is steadied on the other side.
When does the hyoid bone move up?
when you swallow
when you sing a high note
The muscles attached to the hyoid bone can be accessory jaw muscles. What is the main jaw muscle, though?
lateral pterygoid muscle
What are the supra hyoid muscles?
mylohyoid
stylohyoid
digastric
genohyoid
Describe the mylohyoid & its innervation.
This is a big muscle that forms the floor of the mouth. It is a sling w/ a big midline seam connecting it to the mandible.
Innervated by the mylohyoid nerve (branch off inferior alveolar-V3)
Describe the digastric muscle & its innervation.
This muscle has an anterior belly & posterior belly & is found superficial to the mylohyoid muscle. Its anterior belly is innervated by CN5 & its posterior belly is innervated by CN7. Therefore, this muscle comes from 2 different arches, the 2nd & 4th.
Describe the stylohyoid muscle.
This goes from the styloid process to the hyoid bone.
It surrounds the sling of mylohyoid.
What are the infra hyoid muscles?
sternohyoid
thyrohyoid
sternothyroid
omohyoid
Describe the sternohyoid muscle.
this is a full length infra hyoid muscle. it connects from the sternum to the hyoid bone.
Describe the sternothyroid muscle.
this connects from the sternum to the thyroid cartilage
innervated by C1 fibers coming off of CN12
Describe the thyrohyoid muscle.
this connects from the thyroid cartilage to the hyoid bone.
Describe the omohyoid muscle.
this connects from a tubercle on the scapula to the hyoid bone
has superior & inferior bellies & a tendinous part
Where is the genohyoid muscle located?
behind the mylohyoid muscle
a suprahyoid muscle
innervated by C1 coming off of CN12
In general the supra hyoid muscles are innervated by _____ & the infra hyoid muscles are innervated by ______.
Suprahyoid Muscles: Cranial Nerves (exception genohyoid)
Infrahyoid Muscles: Ansa cervicalis –cervical plexus (exception thyrohyoid)
What is the general action of the infra hyoid muscles?
they depress the hyoid bone & the thyroid cartilage.
T/F In terms of muscle length: sternohyoid=sternothyroid + thyrohyoid.
TRUE!!!
What are the infra hyoid muscles also known as?
the strap muscles
What are the 3 muscles of the styloid process?
Stylohyoid
Styloglossus
Stylopharyngeus
What is the course of the stylohyoid muscle? What is its embryological derivative? What is its innervation?
styloid process–>hyoid bone
splits around the digastric muscle
2nd pharyngeal arch
CN7
What is the course of the styloglossus muscle? What is its embryological derivative? What is its innervation?
styloid process–>tongue
post-otic somites
CN 12
What is the course of the stylopharyngeus muscle? What is its embryological derivative? What is its innervation?
styloid process (medial)–>pharynx (posterior lateral)
branchial arch 3
CN9
CN9 hits the stylopharyngeus & innervates it on its way to what job?
on its way to providing sensory innervation to the posterior 1/3 of the tongue
Why does Dr. Sievert like the styloid muscles so much?
b/c it is 3 different embryological derivatives & cranial nerves for 3 muscles from the same place.
What direction does the geniohyoid muscle run on the inside of the mouth?
inferiorly & posteriorly.
Review…what all is found in the carotid triangle?
Carotid Sheath= Common Carotid Artery Internal Jugular Vein Vagus Nerve \+ Ansa Cervicalis
when does the internal carotid artery branch?
not until it enters the cranial cavity
Where does the external carotid artery have its branches?
in the face & neck only
Are there anastomotic connections b/w the internal & external carotid arteries?
Yes, of course! : )
The internal carotid artery goes thru which special bony structure?
the carotid canal
ends up in the circle of willis
T/F The orbit is an important anastomotic connection b/w the internal & external carotid arteries.
True
Describe the course of the internal carotid artery.
goes thru the carotid canal
close relationship w/ the cavernous sinus
The vertebral artery is a branch of what?
the subclavian artery
Describe the course of the vertebral artery.
branches off the subclavian artery goes thru the transverse foramina of C1-C6 passes over the posterior lamina of C1 goes thru the foramen magnum turns into the basilar artery
Describe the relationship of the carotid canal with the foramen lacerum & the jugular foramen on the base of the skull.
the internal opening of the carotid canal is near the foramen lacerum.
The foramen lacerum contains an emissary vein & some cartilage.
the external opening of the carotid canal is more lateral, anterior to the jugular foramen.
What goes thru the jugular foramen? Where does this end up?
the internal jugular vein goes thru the jugular foramen & it ends up in the posterior cranial fossa
When the internal carotid artery goes thru the carotid canal…where does it end up?
in the middle cranial fossae
What’s the deal with the carotid sinus?
it is a swelling at the base of the internal carotid artery
innervated by CN9 (GVA part)
baroreceptor-senses pressure
What’s the deal with the carotid body?
this is a mass of tissue found at the bifurcation of the common carotid artery
innervated by CN9 (GVA part)
chemoreceptor-pO2, pCO2 etc.
If you are looking at the branches of the carotid artery & you see branches off of one of the trunks in the neck..which carotid is this?
Def the external carotid artery b/c the internal won’t branch until it gets into the skull.
So…these GVA fibers from the carotid body & sinus go where in the brainstem?
to the nucleus solitariis tract. the caudal part.
then some of the fibers ascend into the cranial cavity
some of the fibers are involved in reflexes
What types of reflexes are the GVA fibers from the carotid body & sinus involved in? Which structures are involved?
Change BP back to equilibrium via parasympathetics response or sympathetic response.
Parasympathetics: Its neighbor, DMX
Sympathetics: down to preganglionic sympathetic inputs w/ other descending inputs (in a pathway next door to the corticospinal tract)
Change Respiration: phrenic nucleus
What does DMX stand for?
dorsal motor nucleus of the vagus
What are some of the things that go down to the preganglionic sympathetic inputs?
hypothalamus
nucleus solitariis tract
cortex
Which spinal nerves are involved in the phrenic nucleus?
C3, C4, C5
So why does anyone get high BP if you have this awesome carotid sinus as your baroreceptor that can be involved in all of these reflexes?
b/c the carotid sinus & body respond to transience. AFter a while, the body will think that 180/100 mmHg is normal. Yikes!
What is the rostral part of the nucleus solitariis involved in?
taste
The fibers from the baroreceptor of the carotid sinus go in on what? Out on what?
In on CN9
Out on CN10 or sympathetics
What are the branches of the external carotid artery (the lowest branches to the tops)?
SAL FOP MS S: Superficial Thyroid A: Ascending Pharyngeal L: Lingual F: Facial O: Occipital P: Posterior Auricular M: Maxillary S: Superficial Temporal
Describe the course of the superficial thyroid branch of the external carotid artery.
it shoots inferiorly & goes to the thyroid gland
Describe the course of the ascending pharyngeal branch of the external carotid artery.
this is from the posterior aspect of the external carotid artery
it ascends & is a deep branch
it is also small
Describe the course of the lingual branch of the external carotid artery.
this is an easy branch to identify b/c it dives into the oral cavity
**it sometimes comes off of a common facial-lingual trunk.
Describe the course of the facial branch of the external carotid artery.
this branch can be seen over the mandible
**it sometimes comes off of a common facial-lingual trunk
Describe the course of the Occipital branch of the external carotid artery. What is something you always see caught up in it?
it runs to the back of the head
**always see the hypoglossal nerve caught up in it.
Where is the vagus nerve found in the neck?
in the carotid sheath…tucked right b/w the internal jugular vein & the common carotid artery
What is the swelling of the vagus nerve called that is seen after the vagus nerve comes out of the jugular foramen?
it is called the superior & inferior ganglion.
What are the 3 important branches that come off the vagus nerve in the neck region?
- pharyngeal branch–off really high
- superior laryngeal nerve–>internal & external branches
- recurrent largyneal branch aka inferior laryngeal nerve
Where does the internal branch of the superior laryngeal nerve go?
this goes internally into the larynx
gives sensory innervation above the vocal cords, above the laryngeal fold
Where does the external branch of the superior laryngeal nerve go?
this gives motor innervation to the cricothyroid muscle
What is the course of the recurrent laryngeal nerve?
it descends & hooks around the ligamentum arteriosum on the left side, both sides descend into the thorax.
it then ascends & ends up near the thyroid gland (watch out for this in thyroidectomy)
innervates all the muscles of the larynx except the cricothyroid.
gives sensory innervation below the vocal cords, below the laryngeal fold
What is the clinical significance of the recurrent laryngeal nerve descending into the thorax?
this means that lung cancers can easily spread up via this nerve.
What are the 5 components of the vagus nerve?
General Sensory
GVA (w/ it special sense-taste)
Visceromotor
Branchiomotor
How far down does the visceromotor go w/ the vagus nerve?
all the way to the left colic flexure
Which 2 things travel on the nucleus solitariis tract?
GVA & taste
What’s the deal with the branchiomotor of the vagus nerve?
it supplies the structures of the 4th & 6th pharyngeal arches (laryngeal muscles etc)
Which reflexes is the vagus nerve involved in?
carotid-BP reflex (out on 10)
cough reflex
gag reflex
vomit reflex
What are some of the important things that you will see in a slice of medulla?
a line separating the basal plate (motor columns) from the alar plate (sensory columns) inferior cerebral peduncle pyramids medial lemniscus tract & the descending MLF tract spinal tract 5 branchiomotor nucleus hypoglossal nucleus DMX-yeah!
Describe the anastomoses of the arterial supply of the thyroid gland.
superior thyroid artery–from the external carotid artery
inferior thyroid artery (from thyrocervical trunk)–from subclavian artery
What are some of the branches of the thyrocervical trunk?
inferior thyroid artery
transverse cervical artery
suprascapular artery
Describe the venous drainage of the thyroid gland.
superior thyroid veins-IJV
middle thyroid veins-IJV
inferior thyroid veins-brachiocephalic veins directly
What is some weird variant that you can see on the thyroid gland?
can sometimes see a little tongue of thyroid gland sticking out–called the pyramidal lobe. From the descent of the tongue.
What are some of the names of the remnants of the thyroid gland when it descended?
lingual intralingual sublingual prelaryngeal intratracheal substernal (goes into the superior mediastinum)
Describe the sympathetic trunk in the neck region.
it has ascending pre gang fibers from T1-T3 (thorax).
They synapse in 1/3 ganglia.
they travel on cervical spinal nerves as post gang or on blood vessels into the cranial cavity (internal carotid)
What are the ganglia that the pre gang fibers could synapse in?
superior cervical ganglion
middle cervical ganglion
inferior cervical ganglion
Where do you find the sympathetic chain?
deep to the carotid sheath
lying along the pre vertebral muscles
What is Horner’s Syndrome?
disruption to sympathetic chain causes it
Symptoms:
ptosis
flushed face (blood vessel dilation)
dry face (no sweat glands)
constricted pupil (parasympathetic tone dominates)
What are 4 causes of Horner’s Syndrome?
- Damage to sympathetic chain: cut chain above T1–get no post gang sympathetics
- Damage to spinal cord: T1-T3 pregang neurons in lateral horn
- Damage to symp on arteries: on internal carotid artery
- Damage to symp in brainstem: disruption of input to pregang symp from nucleus solitariis tract.
What are the branches off of the subclavian artery?
vertebral artery
internal thoracic artery
thyrocervical trunk
costocervical trunk
What does the costocervical trunk supply?
the rhomboids & the brachial plexus
Describe the lymphatic drainage of the head & neck.
Superficial nodes in the pericervical collar
Superficial nodes in Anterior & posterior cervical groups
These superficial nodes drain to the deep cervical nodes that surround the IJV.
Deep nodes drain to the right lymphatic duct on rights side. Drain to the thoracic duct on the left side.
What are the nodes that are a part of the superficial pericervical collar?
occipital retro-auricular parotid buccal submandibular submental
Some of the pericervical collar lymph nodes can drain to either side of the body. Which ones? What is the clinical significance of this?
submandibular & submental lymph nodes
can drain to either side
Significance: these drain the lips & tongue and can cause spread of cancer
what are the deep cervical nodes?
jugulodigastric node
jugulomyohyoid node
inferior deep cervical node
supraclavicular node/transverse cervical nodes
Which of the deep cervical nodes are called sentinel? What is the clinical significance of this?
these are the supraclavicular nodes
these are a tip off for pathologists about cancer b/c the head, neck, and thorax can drain to these nodes.
The thoracic duct ascends on the ____ side & comes up behind the jcn of which 2 veins?
left side
behind the jcn of the subclavian vein & IJV
