Head and Neck Flashcards
First Branchial Arch derivates
Trigeminal nerve
Incus
Muscles mastication, mylohyoid, anterior belly of digastric, tensor tympani, tensor palati
Second Branchial Arch derivates
Facial nerve
Stapes, styloid process, upper body of hyoid, cornu of hyoid
Posterior belly of digastric, stylohyoid, stapedius.
Third Branchial Arch derivates
Glossopharyngeal
Lower body of hyoid, greater cornu
Stylopharyngeus
Fourth to Sixth Branchial Arch derivates
Vagus, Laryngeal and Recurrent laryngeal
Thyroid, Aryteroid, corniculate and cuneiform
Pharynx, larynx, palate
First Pharyngeal Pouch derivates
Eustacian tube, middle ear, mastoid, antrum
Second Pharyngeal Pouch derivates
Palatine tonsil (tonsillar fossa)
Third Pharyngeal Pouch derivates
Thymus, inferior parathyroid
How many branchial arches
6
How many pharyngeal pouches
4
Fourth Pharyngeal Pouch derivates
superior parathyroid, part of thyroid
Why do some people get thyroglossal cysts?
traces remaining of diverticulum from thyroglossal duct (foramen caecum)
Why do some people get cleft lip?
failue of fusion of frontonasal ad maxillary processes
Why do some people get cleft palate?
failure of fusion of primary (premaxillary) and secondary (hard and soft) palates
Why do some people get spina bifida?
failure to fuse of neural arches
What is the difference between spina bifida occulta and manifesta
occulta = vertebral anomaly, meninges intact
manifesta - meningicoele or meningomyelocoele - associated with hydrocephalus
What are the fascial layers of the neck?
Platysma - superficial layer of muscle anterior neck
Investing fascial layer - around muscles of neck and partotid/submandibular glands
Prevertebral layer - vertebrae and prevertebral muscles. brachial and cervical plexuses, floor of posterior triangle
Pretracheal layer - hyoid to pericrardium. Thyroid, larynx, pharynx, trachea, oesophagus.
Contents of carotid sheath
common (-internal) carotid artery
vagus nerve
internal jugular vein
What is most lateral in the carotid sheath
IJV
Borders of anterior triangle
ramus of mandible
midline of neck
anterior border of SCM
Which nerve innervates the infrahyoid muscles?
ansa cervicalis
What are the infrahyoid muscles?
sternohyoid
sternothyroid
thyromyoid
onohyoid
What action do the infrahyoid muscles produce
open mouth against resistance
Origins of common carotid arteries
right - brachiocephalic
left - aortic arch
At what level does the common carotid bifurcate?
C3 - anterior thyroid
How do you tell the difference between the internal and external carotid in the neck
internal carotid - in sheath and no branches
What are the branches of the external carotid in the neck
Some Attendings Like Freaking Out Potential (Med Students)
Superior thyroid
Ascending pharyngeal
Lingual
Facial
Occipital
Posterior auricular
What are the terminal branches of the external carotid and where do the bifurcate?
Superficial temporal and maxillary
In the parotid gland
Where is the internal jugular vein formed?
continuation of sigmoid sinus
jugular foramen
What is the relation of the IJV to the ICA?
starts posterior and then lateral as it descends
Where does the IJV terminate and what vein does it become?
between heads of the SCM
IJV + subclavian = brachiocephalic
What is the blood supply to the thyroid and the branches?
Superior thyroid - external carotid
inferior thyroid - thyrocervical trunk of subclavian
Thyrodica ima - variant - aotic arch
Superior and middle thyroid veins - IJV
Inferior thyroid vein - brachiocephalic
What are the 3 compartments of the larynx?
supraglottic - above false cords
glottic between false and tru cords
infraglottic - true cords to 1st tracheal ring
Lymphatic drainage of epiglottis
above cords - superficial
below cords - deep
What are the 3 parts of the pharynx?
nasopharynx
oropharynx
laryngopharynx
Epithelium of the pharynx
naso - pseudostratified collumnar
oro and laryngo into oesophagus = stratified squamous
Borders of the posterior triangle
front - posterior border SCM
back - anterior border trapezius
apex - SCM and trapezius attachments
base - middle 1/3 clavicle
Floor - scalene
roof - investing layer cervical fascia
Relations of accessory nerve
posterior to SCM and under trapezius - supplies both
sits on levator scapulae
Course of phrenic nerve
cervical plexus - C234, lateral border scalene anterior - over the scalene anterior, lateral to subclavian vein - leaves neck between the subclavian artery and vein
Branches of subclavian artery
vertebral
internal mammary (thoracic)
thyrocervical trunk
costocervical trunk
termiates at axillary artery
brachial plexus relations to scalenes and subclavian artery
between scalene anterior and medius, which are btih infront of artery.
Where is Erb’s point on brachial plexus?
C5-6
Where is Klumpke’s point on brachial plexus
C8-T1
Brachial plexus sections
roots (5) trunks (3) divisions (6) cords (3)
Where does the long thoracic come of brachial plexus?
roots c3,4,5
Where does Supraspinatus come off brachial plexus?
upper branch
Where does Supraspinatus come off brachial plexus?
upper trunk
Where do subscapularis and thoracodorsal come off brachial plexus?
posterior cord
How many nuclei facial nerve?
4
motor
trigeminal (sensory)
solitarus (taste)
salivary (preganglionic parasympathetic)
Where does rigeminal nerve originate?
pons
Where does the facial nerve converge when leaving the brainstem?
cerebello pontine angle
where does the trigemnial nerve converge
meckels cave
What foramen does the facial nerve branch through?
internal auditory meatus
greater petrosal nerve - formaen lacerum
What foramina do the trigeminal nerve branches pass though?
ophthalmic - suprioe orbital fissue
maxillary - rotundum
mandibular - foramen ovale
What is the first branch of the facial nerve and where?
greater petrosal
at the geniculate ganglion
before entering the middle ear
What are the branches of the facial nerve before entering the stylomastoid foramen
posterior auricular and chorda tympani
nerve to stapedius
What does the chorda tympani supply?
submandubular and lacrimal glands
taste anterior 2/3 tongue
what muscles does the trigeminal nerve supply?
muscles of mastication
masseter
temporalis
medial and lateral pterygoids
anterior belly digasttric
mylohyoid
tensor tympani and palatini
where do the motor fibres if trigeminal nerve run?
along the mandibular branch
Most superficial structure passing thorugh submandubular gland
marginal mandibular nerve
Artery damaged during excision of submandibular gland
facial
name for submandibular gland
whartons ducts
