Head and Neck Review Flashcards
What embrological tissue gives rise to the facial bones?
Neural crest cells
What foramen does CN V traverse to supply subcutaneous innervation to the skin superficial to the frontal bone?
Supraorbital foramen (supraorbital branch of CN V-1)
What foramen does CN V traverse to supply subcutaneous innervation to the skin superficial to the maxilla?
The infraorbital foramen
from CN V-2
What foramen does CN V traverse to supply subcutaneous innervation to the skin superficial to the maxilla?
Cutaneous branches of CN V-1
Supraorbital n.
Supratorchlear n. (more medial)
Infratrochlear n.
External nasal n. (from an. ethmoidal branch of CN V-1)
Lacrimal (CN VII hitchikes)
Cutaneous branches of CN V-2
Infraorbital n. (medial aspect of cheek)
Zygomatico temporal n.
Zygomatico facial n.
Cutaneous branches of CN V-3
Mental n. (continuation of inf. alveolar)
Buccal n.
Auriculotemporal n. (skin on the side of the head and TMJ) - CN IX hitchhikes after synapsing on otic ganglion
Cutaneous branches supplying the posterior head and neck
Supraobital and supratrochlear nerves branch from ______ ?
The frontal n. (branch of CN V-1)
All of CN V-1 is sensory
Internal and external nasal and infratrochlear nn. branch from ______ ?
The Nasocilliary n. (branch of CN V-1)
What supplys the affarent fibers for the corneal reflex?
CN V-1 (the ciliary branch of the nasociliary n.)
Type of fibers of CN V-2
Only sensory
Trigeminal ganglion
Purely sensory cell bodies (no synapses)
What supplies sensory fibers to the upper teeth and gums?
The superior alveolar nn (from CN V-2)
What supplies sensory innervation of the hard and soft palates?
Hard palate - greater palantine branch of CN V-2
Soft palate - lesser palantine branch of CN V-2
Hitchhikers of CN V
CN III ciliary ganglion
CN VII pterygopalantine ganglion - greater petrosal n (hithchike CN V-2) to supply mucosa and lacrimal gland
CN VII - chorda tympani travels with the lingual n. (CN V-3) and synapses at the submandibular ganglion
CN IX otic ganglion - lesser petrosal branch synapses at otic ganglion and exits via the auriculotemporal nerve (carrying parasympathetic fibers from CN IX) to innervate parotid
Accomodation
Postsynaptic parasympathetic postganglionic cell bodies - ciliary
Lens balls up (ciliary m. contracts), iris constricts, and eyes move medially - converge (focus on close object)
Sensory ganglion of CN VII
Geniculate ganglion
What level does the carotid bifurcation occur?
At CV4
List the levels of the hyoid bone, carotid bifurcation, laryngeal prominence, and cricoid cartilage
Important ligaments of superior cervical vertebrae
Tissue that connects frontalis m. and occipitalis m.
The galea aponeurotica
Muscles of facial expression
What innervates the platysma m.
CN VII
Muscles supplied by ansa cervicalis n.
Sternohyoid
Omohyoid
Sternothyroid
Fibers from C1-3
What innervates the thyrohyoid m.?
C1 only (not part of ansa cervicalis) - hitchhikes with CN XII (hypoglossal n.)
What innervates the geniohyoid?
C1 only (not part of ansa cervicalis) - hitchhikes with CN XII (hypoglossal n.)
What innervates the stylohyoid
CN VII
What joins the facial vein to drain into the IJ?
The facial vein joins the retromandibular to drain into the internal jugular
Innervation of submandibular gland
CN VII chorda tympani (parasympathetic from submandibular gland)
What nerves hitchhike with the hypoglossal nerve?
C1 to the thyrohyoid/geniohyoid mm. and the superior root (ansa cervicalis)
Where does the descending cervicalis of ansa cervicalis originate?
The C1-2 loop of the cervical plexus
What muscles attach to the styloid process?
Stylohyoid (CN VII)
Stylopharyngeus (CN IX)
Styloglossus (CN XII)
Stylopharyngeus is the only muscle supplied by CN IX
Where does the phrenic n. originate?
Off the C3-4 loop of the cervical plexus and C5 from the brachial plexus
Branches of the right subclavian artery
What parasympathetic n. innervates the carotid sinus?
CN IX is the afferent (sensory portion)
-Also afferent to carotid body (detects pCO2)
Main branches of the external carotid artery
External carotid a
6 branches in neck/face
1 medial:
Ascending pharyngeal a
2 posterior:
Post auricular a
Occipital a
3 anterior:
Facial a
Lingual a
Sup thyroid a
Internal laryngeal a
Structures that drain into the nasopharynx
Three areas draining into to one area each
Structures that drain into the nasopharynx
Three areas draining into one area
Arterial supply to nasopharynx mucosa
Nerves of the nasopharynx
Sympathetics that innervate carotid
Carotid nerve becomes the deep petrosal and joins with the great petrosal (CN VII) to form the vidian nerve before the sympathetic fibers pass through the pterogopalantine ganglion
Parasympathetics of the nasopharynx
Via the greater petrosal nerve (CN VII) that synapse at the pterygopalantine ganglion and hitchhike on CN V-2 to innervate the mucosal glands
Parasympathetic innervation of the lacrimal gland
Autonomic innervation of nasopharynx
Ciliary ganglion
Parasympathetic ganglia
Otic ganglion
Pterogopalantine ganglion
Submandibular ganglion
Ciliary ganglion
Where does the lesser petrosal n. synapse before reaching its target tissue?
The lesser petrosal n. (CN IX) synapses at the otic ganglion where the auriculotemporal branch (carrying hitchhiking postsynaptic parasympathetic fibers) leaves innervating the parotid gland
Sensory ganglia
Trigeminal ganglion
Geniculate ganglion
Only muscle of mastication that retracts mandible?
Opposite of protrusion
Posterior fibers of temporalis
How does the mandible fully open?
Submandibular muscles that are innervated by CN VII
Only muscle supplied by CN IX
stylopharyngeus
Styloglossus (CN X)
How to determine the lingual (CN V3) vs hypoglossal nn at the mandible
Lingual wraps around the submandibular duct
What lies deep to the hyoglossus muscle?
The lingual artery
What muscles in the face/neck are innervated by C1
The geniohyoid and the thyrohyoid mm. are innervated by C1 from cervical plexus hitchiking with the hypoglossus n.
The chorda tympani hitchhikes onto what nerve to innervate the sublingual and submental glands?
Onto the lingual n.
The tongue
Posterior 1/3 gets taste and general sense from CN IX
Root of tongue gets general sense and taste from CN X
Embryonic tissue derivation of the tongue
Anterior 2/3 - ectoderm (from stomodeum) - no gag reflex
Posterior 1/3 - (endoderm down to rectum - afferent limb of gag reflex (CN IX)
Efferent portion of gag reflex - to constrictors (controlled by CN X)
Arteries of the palantine tonsil
What borders the palantine tonsil
Where does the retropharyngeal space run longitudinally
From the base of the skull to the superior mediastinum
What is the only scalene muscle that attaches at the second rib (as opposed to the first)
The posterior scalene m.
What does the tensor veli palatini arch around to tense the soft palate?
The hammulus of the pterygoid plate
Closes off the soft palate
Pterygomandibular raphe
What attaches the superior pharyngeal constrictor m. to the buccinator m.
Salpingopharyngeus
What node swells with infections of the palatine tonsils?
The jugulodigastric node
What node swells due to metastatic disease of the anterior 2/3 of the tongue?
The submental nodes
What connects the right and left lobes of the thyroid?
The isthmus
The thyroid is derived emryonically from the foramen cecum - the pyramidal lobe is a remnant of the thyroglossal duct
What innervates the cricothyroid m..
The external laryngeal n. (only structure it innervates) the internal laryngeal nerve is only sensory fibers
Ext. laryngeal n travels with the sup thyroid a.
The ext/int laryngeal nn. are branches of the superior laryngeal n.
Veins of the anterior larynx
What is the opening into the larynx
Space between the two vocal chords
The rima glottidis
Unpaired cartilagenous elements of the larynx
Three paired cartilagenous elements of the larynx
Remember arytenoid - adjust position and tension of vocal cord for phonation
Attached to cricoid cartilage
Site of emergent airway
At the cricothyroid membrane
Only cartilagenous element of larynx with a complete ring
The cricoid cartilage
How the airway is closed off naturally
The suprahyoid muscles pull up (contract) the larynx, and the hyoglossus muscle pulls the tongue back to close the epiglottis
Superior internal fibers of the thyroaretenoid m.
vocalis m. - can contract discretely along its longitudinal axis
What is the only muscle of the vocal chord that abducts?
The posterior cricoarytenoid m.
Horner’s syndrome ptosis
Mild ptosis (superior tarsal muscle is smoot m. that is innervated by sympathetic fibers)
Parasympathetic portion of CN III
The lower division synapses at the ciliary ganglion and go to muscles of the ciliary body (ball up lens) and iris (constricts pupil) via short ciliary nn.
Sensory for the corneal reflex
Nasociliary branch of CN V-1 (opthalmic n.)
Remember:
Motor is from CNVII (greater petrosal n.) innervating the orbicularis oculi m. to close the eye
Where does the chorda tympani n. exit the middle ear
The petrotympanic fissure into the mandibular fossa
Remember - parasympathetic to para and submandibular glands
Chorda tympani is internal to malleus and external to the incus
Where does the tympanic n. enter the middle ear?
The tympanic branch of the glosspharyngeal n. enters the inferior wall of the middle ear through the tympanic canaliculus (opening between the carotid canal and the jugular foramen)
Exits the middle ear into the medial cranial fossa and then back out of the skull foramen ovale/spinosum/other unamed foramen
What is posterior to the antrum?
Ethmoidal air cells
Most of the venous system is in what meningeal layer?
The subarachnoid space
Where do the ophthalmic veins drain?
Into cavernous sinus,
Remember opthalmic v. anastomoses with facial v. and the pterygoid plexus
What structures can be affected by infection/tumor of the cavernous sinus?
Int carotid a (sympathetics on carotid)
CN III, IV, CN V-1 and V-2
Sympathetics and CN VI are most likely to be affected by something affecting the cavernous sinus
What structures can be affected by infection/tumor of the cavernous sinus?
Int carotid a (sympathetics on carotid)
CN III, IV, CN V-1 and V-2
Sympathetics and CN VI are most likely to be affected by something affecting the cavernous sinus
What surrounding structures are most likely impacted by a tumor of the pituatary gland?
Optic chiasm
Structures running longitudinall (posterior to anterior) through the cavernous sinus.
All muscles of the glossus receive motor supply from _____ except for _____
All muscles of the glossus (tongue) receive motor innervation from CN XII except for the palatoglossus m. which receives innervation from CN X (because it is a muscle of the palate)
All muscles of the palate receive motor innervation from _____ except for _____
All muscles of the palate receive motor innervation from CN X except for tensor veli palatini which is supplied by CN V-3
