Area under SCM Flashcards
What are the general contents of the carotid sheath
common and internal carotid aa internal jugular v vagus n ansa cervicalis (superior root is in the sheath) inferior on its lateral surface deep cervical lymph nodes
within the carotid sheath where do the a and v and n lay respectively
a lies medial and anterior
v lies lateral and posterior
n between vessels
Where do the common carotids branch from
left from arch of aorta
right from brachiocephalic trunk
what fascias of the neck contribute to carotid sheath
investing, pre-tracheal, pre-vertebral and cervical fascias
where is the carotid sinus found
dilated distal common carotid and proximal internal carotid
what does the carotid sinus sense
Pressure changes, HR
where is the carotid body located
at carotid bifurcation
what does the carotid body sense
changes in O2 tension, increase in rate and depth of respiration
what n carries afferents from carotid body
IX
Where does the internal carotid a enter skull
carotid canal
what are the branches of the external carotid a
superior thyroid ascending paryngeal lingual facial occipital posterior auricular terminates as maxillary and superficial temporal aa
what are the boundaries of the carotid triangle
anterior border SCM, posterior border of superior belly omohyoid, inferior border of posterior belly digastric
What can be found in the carotid triangle
carotid bifurcation, internal jug v, vagus and hypoglossal nn and sympathetic trunk
if patient has voice changes after manipulation to carotid triangle area what nn are responsible
vagus and recurrent laryngeal because innervate mm of larynx
Why do atherosclerotic plaques form at carotid bifurcation?? which side is most common
turbulence
internal carotid area is usually more occluded
what is a carotid endarterectomy
removal of plaque from carotid bifurcation
What are the major branches of the superior thyroid a
superior laryngeal a
anterior branch
posterior branch
What are the branches of the ascending pharyngeal a
pharyngeal
palatine
inferior tympanic
meningeal
what are the branches of lingual a
dorsal lingual
deep lingual
sublingual
what is a “wet stroke”
hemorrhagic stroke, inside or around brain tissue
what is a “dry stroke”
ischemic stroke, occluded artery supplying brain tissue
where does facial a arise from off external carotid
either as trunk with lingual or right after it
what are the submandibular branches of the facial a
tonsillar, ascending palatine, glandular, muscular, submental
where does the occipital a run
passes in groove between transverse process of atlas and mastoid process
pierces fascia where trapezius and SCM come together
parallels greater occipital n
what are the main branches of occipital a
sternocleidomastoid meningeal a auricular mastoid descending branch
what structure crosses over the occipital a where it branches of external a
hypoglossal n
what are the branches of the posterior auricular a
muscular branches parotid branches stylomastoid auricular occipital
How does the internal jugular v receive blood
from dural venous sinuses
where does the internal jugular v begin
at jugular foramen as superior jugular bulb
where does the internal jugular vein end
as inferior bulb posteiror to sternoclavicular joint where it joins subclavian v to form brachiocephalic v
what are some tributaries to internal jugular veins
occipital vv pharyngeal vv lingual v facial v as common facial v superior and middle thyroid v
where can the right internal jugular v be accessed for Dx purposes
apex of triangle between clavicular and sternal heads of SCM with needle inserted lateral to common carotid pulse at 30 angle inferiorly to ipsilateral nipple
What type of fibers are in vagus CN X
SVE, SVA, GVA, GSA and GVE-P
what mm are inn by the SVE portion of vagus
pharynx, palate and laryngeal mm also proximal 1/3 esophagus
What are the general afferents from vagus
GVA carotid body, epiglottis, larynx, respiratory system, GI to terminal colon
GSA to external ear, external auditory meatus, tympanic membrane, posterior cranial fossa dura mater
What is the SVA portion of vagus
taste for epiglottic portion of tongue
what is the GVE-P of vagus
PAN to heart, lungs and GI system
where does vagus n exit brainstem
at medulla
where does the vagus n exit skull
jugular foramen
where does the vagus n eneter the thorax
R- between subclavian a and right brachiocephalic v
L- between junction of L common carotid with L subclavian and L brachiocephalic v
What other nn does the vagus communicate with
IX, XI XII superior cervical ganglion and spinal nn C1 and C2
What are the branches of vagus n in the neck
meningeal auricular pharyngeal nerve to carotid body superior laryngeal cervical cardiac branches recurrent laryngeal n
describe meningeal branch of vagus n
GSA to dura of posterior cranial fossa
describe auricular branch of vagus n
GSA posterior surface of pinna, auditory canal and external surface of tympanic membrane
describe pharyngeal branch of vagus n
SVE branches to mm of pharynx and soft palate
describe nerve to cartoid body off vagus
from pharyngeal, afferent limb from O2 chemoR in bifurcation
GVA
where does superior laryngeal n course in regards to the carotid sheath
medial
What are the branches of superior laryngeal n
internal SVA GVA GVE-P
external SVE
what does the internal branch of superior laryngeal n provide
taste and general sensation and PAN to base of tongue (mucous glands), also to epiglottis, aryepiglottic folds and internal portion of larynx above true vocal fold
What a does the external branch of superior laryngeal run with
superior thyroid a
what type of fibers are in external branch superior laryngeal n and inn what?
SVE
circothyroid m and inferior constrictor m
what are the cervical cardiac branches of vagus and type of fiber information
GVE-P GVA
superior and inferior cardiac nn
where are the superior cardiac nn found
near origin of superior laryngeal n and descend medial to carotid sheath
where are the inferior cardiac nn from vagus found
in root of neck near 1st rib
what nn form deep cardiac plexus
superficial cardiac plexus?
deep: superior cardiac nn and right inferior cardiac nn
superficial: left inferior cardiac n
What type of fibers are within the recurrent laryngeal n
SVE GVE-P and GVA
what structures are inn by recurrent laryngeal
mm of larynx, secretory to mucous
sensory to mucosa inferior to true vocal folds
where are the recurrent laryngeals found
R n recurs around subclavian a
L n recurs around aortic arch at ligamentum arteriosum
Once the recurrent laryngeal nn are in the larynx what are they called
inferior laryngeal nn
what are the branches off recurrent laryngeal nn
cardiac branches to deep cardiac plexus
branches to mm and glands of trachea and esophagus
pharyngeal branches to inferior constrictor
laryngeal branches to all m of larynx EXCEPT cricothyroid
What divides the deep cervical lymph nodes into superior and inferior
omohyoid m
what lymph nodes are found in superior carotid triangle
superior deep cervical
retropharyngeal, deep parotid, jugulodigastric and jugulo-omohyoid
where do the superior deep nodes drain to
inferior nodes
where do the inferior deep cervical nodes receive lymph from
superficial cervical superior deep accessory chain of posterior triangle transverse cervical nodes juxtavisceral nodes of anterior triangle: infrahyoid, pre-laryngeal, pre-tracheal and paratracheal
what are the jugular lymph trunks
on L: thoracic duct
R: subclavian and right bronchi-mediastinal trunks join to make right lymphatic duct that enters where internal jug meets subclavian
in radical neck dissection ofr metastatic cancer in supraclavicular nodes what lymph is taken out
all of the deep cervical lymph and cutaneous branches of cervical plexus
Where does CN XII leave skull
hypoglossal canal medial to internal jugular v and internal carotid a
What spinal nn make up cervical plexus
C1-C4 ventral rami
what is inn by cervical plexus
motor: deep cervical mm, infra hyoids and diaphragm
sensory: lateral head, neck, superolateral shoulder and upper anterior thorax
carries all postganglionic sympathetics for C1-4
What are the sensory nn off cervical plexus and contributing levels
lesser occipital C2-3
great auricular C2-3
transverse cervical n C2-3
supraclavicular nn C3-4
phrenic C345
sensory fibers C1C2 join hypoglossal to post dura
proprioceptive C2-4 in spinal accessory: 2-3 to SCM 3-4 to trapezius
What are the motor nn off cervical plexus
ansa cervicalis
C1 in hypoglossal
muscular branches to longus capitis, longus coli and middle scalene
phrenic
What levels give rise to superior root of ansa cervicalis and inn what
C1-C2
what levels give rise to inferior root of ansa cervicalis
C2-C3
what mm are inn by the ansa cervicalis individual branches
infrahyoid mm
sternothyroid sternohyoid and omohyoid
what cord level inn the geniohyoid and thyrohyoid mm
C1- run in hypoglossal
where does accessory phrenic n most commonly arise from
C5 spinal n
