Head and Neck Anatomy Flashcards
CN I
Olfactory
Special sensory: smell
CN II
Optic
Special sensory: vision
CN III
Occulomotor
Motor: -
superior rectus
- inferior rectus
- medial rectus
- inferior oblique
- levator palpebrae superioris
Parasympathetic:
- changes lens shape for accommodation
- constricts pupil and ciliary muscle
CN IV
Trochlear
Motor: superior oblique
CN V
Trigeminal
SENSORY!!! and motor (V3 only)
V1 = Opthalmic
V2 = Maxillary
V3= Mandibular
CN VI
Abducens
Motor: lateral rectus
CN VII
Facial
Sensory: taste on anterior 2/3 of tongue
Motor:
- facial expression
- Stapedius muscle to dampen sound
- Orbicularis occuli to close eyes
Parasympathetic: “spitting and crying” - lacrimal gland - nasal mucosa - 2/3 salivary gland
CN VIII
Vestibulocochlear
Sensory: balance and hearing
Motor: inhibitory efferents allow hair cells to modify sounds coming in
CN XI
Glossopharyngeal
Sensory: gag reflex, sensation in the back of the tongue, hearing,
Parasymathetic: parotid salivary glands
CN X
Vagus
Sensory: Parasympathetic: Motor:
CN XI
Spinal Accessory
Motor: to sternocleidomastooid then trapezius muscle to lift shoulders up and down, move head side to side
CN V1
Opthalmic nerve
Sensory: forehead, cornea, tip of nose
CN V2
Maxillary nerve
Sensory: cheek, upper lip, roof of mouth
CN V3
Mandibular nerve
Sensory: chin, bottom lip
Motor:
- Anterior belly of digastric (nerve to myohyoid)
- Myohyoid (nerve to myohyoid)
- Temporalis (deep temporal)
- Tensor palati
- Tensor tympani- to dampen sound
- Lateral pterygoid nerve
- Medial pterygoid nerve
- Masseter
Branches of V1
NFL
Nasocilliary
Frontal
Lacrimal
Branches of CN VII that innervate orbicularis occuli
Temporal branch: superior eyelid
Zygomatic branch: inferior eyelid
CN XII
Hypoglossal
Motor: movement of tongue
Three cranial nerves whose nuclei are not located in brainstem
CN I, II, XI
Spinal roots of CN XI
C1-C5
Cranial nerves that contain PRESYNAPTIC PARASYMPATHETIC fibers
3, 7, 9, 10
Special sense only CN
1, 2, 8
Motor only (striated)
IV, VI, XI, XII
Two layers of dura
Periosteal layer (continuous with bone) Intermeningial layer (continuous with spinal cord dura)
3 cranial meninges
- Pia mater 2. Arachnoid mater 3. Dura mater
How is the arachnoid mater held against the dura?
pressure from CSF
3 parts of the arachnoid space
- granulations (allow CSF absorption into venous structures) 2. trabeculae (merges with pia) 3. sub arachnoid space
rupture of middle meningeal artery
due to hard blow to the head
blood strips dura from cranium
arterial in origin
Epidural hemorrhage
separates dura/arachnoid
due to blow to head that jerks brain inside cranium
venous in origin
Subdural hemorrhage
due to aneurysm
arterial in origin
Subarachnoid hemorrhage
what exits the supraorbital foramen?
V1 supraorbiral branch
what exits the infraorbiral foramen?
V2
Portion of skull the middle meningial arteriy lies under
Pterion
skull fracture at middle meningial artery causes
epidural hematoma
is the groove/hiatus for greater or lesser petrosal more ANTERIOR?
Lesser petrosal nerve
Which is more ANTERIOR, jugular foramen or internal auditory meatus?
internal auditory meatus
What passes through the stylomastoid foramen?
Facial Nerve (CN VII)
What passes through the jugular foramen?
jugular vein
CN IX, X, XI
What passes through the carotid canal?
internal carotid artery
What exits through the hypoglossal canal?
Hypoglossal nerve
What passes through the foramen spinosum?
Middle meningial artery
What exits through foramen rotundum?
V2
What exits through foramen ovale?
V3
What exits through the cribiform plate?
Olfactory nerve
What exits through the optic canal?
Optic nerve and opthalmic artery
What exits through the superior orbital fissure?
CN III, IV, V1, VI
What exits through the internal acoustic meatus?
CN VII, VIII
What exits through the hypoglossal canal?
CN XII
infection of the arachnoid and pia mater
meningitis
dizziness, nausea, fatgue, metalic taste in mouth
CSF leak from subarachnoid space to dura
interruption of normal SCF absorption through the arachnoid granulations
Hydrocephalous
Stroke vs TIA
Stoke: results in impaired neurological function after 24 hours
TIA: Impairment resolves within 24 hours
CN I exits cranial cavity..
cribriform plate/foramina
CN II exits the cranial cavity…
Optic canals
CN III exits the cranial cavity…
superior orbital fissure
CN IV exits the cranial cavity…
suprior orbital fissure
V1 exits the cranial cavity…
superior orbital fissure
V2 exits the cranial cavity…
foramen rotundum
V3 exits the cranial cavity…
foramen ovale
CN VI exits the cranial cavity…
superior orbital fissure
CN VII exits the cranial cavity…
internal auditory meatus
CN VIII exits the cranial cavity…
internal auditory meatus
CN IX exits the cranial cavity…
jugular foramen
CN X exits the cranial cavity…
jugular foramen
CN XI exits the cranial cavity…
jugular foramen
CN XII exits the cranial cavity…
hypoglossal canal
levator palpebrae superioris innervation
CN III and sympathetics
what do the levator palpebrae superioris and superior tarsal muscles attach to?
tarsal plate
superior tarsal muscle innervation
sympathetics
layer of the eye that contains blood vessels to give “blood shot” appearance
bulbar conjunctiva
ptosis
drooping eyelid due to loss of sympathetics to superior tarsal muscle
2 symptoms of Horner’s Syndrome
- ptosis
- miosis
Horner’s syndrome results from
loss of sympathetic nerve supply to the head
Lesion to CN III (2 things)
- completely closed eyelid
- mydriasis (due to unopposed sympathetics)
Flow of tears
- lacrimal gland
- puncta
- lacrimal canaliculi
- lacrimal sac
- nasolacrimal duct empties into nasal cavity
CN III innervates what eye muscles
levator palpebrae superioris
superior rectus
medial rectus
inferior rectus
inferior oblique
CN IV innervates what eye muscles
superior oblique
CN VI innervates what eye muscles
lateral rectus
Branches of the nasocilliary nerve
Short ciliary
Long ciliary
Anterior and Posterior Ethmoidals
branches of frontal nerve
supraorbital
supratrochlear
Long and short ciliary nerves go to
globe of eye
ethmoidals of V1 nasociliary go to
nose
what branch of V1 supplies sensation to the forehead?
Frontal
Supraorbital is more superior to supratrochlear
long ciliary nerve has what type of fibers from what ganglion
postsynaptic sympathetic
superior cervical ganglion
short ciliary nerve has what two types of fibers
- postsynaptic parasympathetic from ciliary ganglion
(presynaptic fibers are from CNIII)
- postsynaptic sympathetic
(from superior cervical ganglion)
What do postsynaptic parasympathetic fibers in short ciliary nerves do?
accommodation and pupil constriction
where does the superior cervical gangion come from?
carotid plexus
what nerves are responsible for the corneal reflex?
long and short ciliary fibers of V1
Presynaptic parasympathetic fibers to the ciliary ganglion are from what?
CN III
4 things pass through the cavernous sinus
CN III, IV, VI on their way to the superior orbital fissure
Internal Carotid Artery
Pathway of postsynaptic sympathetic fibers to orbit
- come from superior cervical ganglion
- hitchhike on ICA
- jump off ICA and hitchhike on long and short ciliary nerve fibers
- go to globe of eye and to levator palpebrae superioris
Pathway of parasympathetic fibers to orbit
CN III to ciliary ganglion through SHORT ciliary fibers to globe of eye
4 parasympathetic ganglion to head
3977 COPS
CN III: ciliary ganglion
CN IX: otic ganglion
CN VII: pterygopalatine ganglion
CN VII: submandibular ganglion
Opthalmic venous drainage pathway
superior orbital fissure > cavernous sinus > internal jugular via superior and inferior petrosal sinuses
Pathway of opthalmic artery
internal carotid branch > through optic canal > ceneral artery of the retina dives into CN II
Lesion of CN VI will result in
adducted eye (due to unopposed action of MR)
CN III lesion results in…
- closed eyelid (loss of innervation to levator palpebrae superioris)
- mydriasis (loss of parasympathetics to iris, unopposed sympathetics)
- abducted eye (unopposed action of lateral rectus, CN VI)
CN IV lesion results in…
- extorted and slightly elevated eye (unopposed IO)
- pt compensating by tilting away from the affected side and flexing head
Outer layer of the globe (3 parts)
- sclera
- cornea
- (corneal) limbus
Middle layer of the globe/uveal tract (3 parts)
- choroid
- ciliary body with ciliary processes
- iris stroma
embryonic origin of melanocytes of the iris
neural crest
Inner layer of the globe (5 parts)
- retinal pigment epithelium (RPE)
- neural retina
- ora serrata
- anterior projections of ciliary processes
- posterior iris
Near Synkinesis Reflex is a response to stimulus consisting of: (3 things)
- Acommodation
- Convergence
- Miosis
Lens looses elasticity with age and does not get FATTER despite the same contraction of circumfrential muscle in the ciliary body
presbyopia
Termination of the retina
ora serrata
2 vascular supplies to retina
- central retinal artery to inner 2/3
- choroidal vasculature to the outer 1/3
what does rhodopsin do?
It’s in the photoreceptor cells of the retina… it phototransduces light into an electrical signal that excites neurons.
These excite ganglion, which send AP through CN II
VISION
Primarily for dim light, black and white
rods
Primarily for brigh light, color
Cones
where retinal nerve fibers come together to exit the eye as the optic nerve
optic disc
“blind spot”
optic disc
responsible for central vision
macula
greatest density of cones
macula
multiple layers of ganglion here as opposed to only one elsewere in the eye
macula
center of the macula
fovea centralis
Loss of central vision is due to
macular degeneration
neural retina attaches to the RPE by
ion pumping of the RPE
Histological components of the lens (3)
- capsule (type IV collagen)
- epithelium (simple cuboidal epithelium)
- fibers (crystalin alpha, beta, gamma)
Embryologic origin of the lens
surface ectoderm
3 anatomical layers of the lens
- capsule
- cortex
- nucleus
Disease associated with lens dislocation
Marfan’s Syndrome
= a crystaline lens that has lost its transparency
cataract
Risk factors for cataracts
DM
UV light
Smoing
Trauma
Aging
Meds (steroids)
Systemic Dz (Down’s, myotonic dystrophy)
Histology of the conjunctiva
stratified columnar epithelium with goblet cells
Embryologic origin and type of collagen in the sclera
neural crest; type 1 collagen
Why is the sclera opaque?
IRREGULAR distribution of type 1 collagen
Why is the cornea clear?
REGULAR distribution of type 1 collagen and complete avascularity
Where the sclera and the cornea meet
limbus
Major focusing power of the eye
cornea
curvature irregularities of the cornea causes
astygmatism
What nerve triggers the blink reflex?
V1
If the cornea is avascular, how does it recieve nurtrition? (3)
- tear film
- lateral diffusion from limbus vasculature
- aqueous humor in anterior chamber
5 layers of the cornea
Elephants Bring Silly Dumbo Everywhere
- Epithelium
stratified, squamous non-keritonized
- Bowman’s layer
- Stroma
type I collagen
- Descement’s layer
type IV collagen
- Endothelium
contains ATP-driven pumps that remove water from teh stromal matrix to preserve the spacing that maintains corneal optic clarity
degenerative dz that causes protrusion of the cornea into a cone shape
keratoconus
Which layer of the cornea is affected in keratoconus?
Bowman’s layer
2 fun facts about corneal transplants
- only part of the eye we can transplant
- does not require HLA or blood type matching
the space formed where the cornea and the iris meet
the angle
Flow of aqueous humor
- produced by epithelial cells of the ciliary processes in the posterior chamber
- flows behind iris
- flows through the iris into the anterior chamber
- drained by Schlemm’s canal in the angle
Formation of aqueous humor and secretion into the posterior chamber is the result of three things:
- active secretion
- ultrafiltration
- simple diffusion
purpose of aqueous humor
to provide nutrients to the cornea and lens
2 major routes of aqueous humor outflow
- trabecular outflow: pressure-dependent
- uveoscleral outflow: pressure-independent
pathway of trabecular outflow for aqueous humor
out of anterior chamber through trabecular meshwork > Schlemm’s canal > scleral veins > cavernous sinus
Pathophysiology of open-angle glaucoma
dysfunctional outflow/obstruction leads to increased IOP, which kills optic nerve cells
Describe loss of vision in open-angle glaucoma
SLOW and painless. goes from periphery to the center. patients don’t realize it’s happening
3 main risk factors for open-angle glaucoma
increasing age
FHx
African American
4 portions of the optic nerve
- nerve fiber
- prelaminar
- laminar
- retrolaminar
the primary site of axonal injury to ganglion cells in glaucoma
lamina cribrosa
lamina cribrosa
= specialized part of the sclera where the optic nerve passes through
3 C’s of a glocomatous optic nerve
Cupping: central depression of the optic disc is larger than normal
Color: pale instead of pink
Contour: sharp margins
2 muscles attach to to mastoid process
- SCM
- postior belly of digastric
What cranial nerve exits the skull through the stylomastoid foramen?
CN VII
Carotid canal terminates at articuation with the sphenoid bone to form what?
foramen lacerum
Where does corda tympani exit the temporal bone?
petrotympanic fissure
The gap between the petrous portion of temporal the bone and the occipital bone
jugular foramen
What runs in the hiatus of facial canal?
greater petrosal nerve
The petrous ridge of the petrous portion of the temporal bone is the location of two things:
- attachment of the tentorium cerebelli
- superior petrosal sinus
Real name for eustacian tube
pharyngotympanic tube
3 branches the facial nerve gives off before exiting the skull
- greater petrosal nerve
- chorda tympani
- tiny branch to the stapedius muscle
Tensor tympani muscle innervation
CN V3
where does the largest portion of CN VII exit the skull?
stylomastoid foramen
the opening of the posterior wall of the middle ear cavity that leads to the mastoid air cells
aditus ad antrum
portion of the malleus that attaches to the tympanic membrane
handle of the malleus
tip of the handle of the malleus attaches to the…
umbo
hyperaccusis is associated with lesion of what cranial nerve?
VII (stapedius muscle)
stapedius originates from where?
posterior wall of the middle ear cavity
the head of the stapes articulates with what?
long process of incus
the base of the stapes attaches to the…
oval window
innervation of the stapedius muscle
CN VII
Mastoiditis endangers what nerve?
Facial nerve
the promontory in the middle ear cavity is due to what?
deeper lying cochlea
what nervous structure is found on the promontory in the middle ear cavity?
Tympanic plexus
the tympanic plexus is from what nerve?
sensory of CN XI
Some branches of CN XI go into the temporal bone via canaliculi. What’s the risk?
otitis media
describe the fibers that make up the greater petrosal nerve
preganglionic parasympathetic
from CN VII
going to the lacrimal gland
describe the fibers that make up the lesser petrosal nerve
preganglionic parasympathetic
from CN IX
to the parotid gland
continuation of the tympanic plexus
part of the tympanic membrane that doesn’t vibrate as much
pars flacida
pars flaccida is in what quadrant of the TM?
posterosuperior
cone of light is in what quadrant of the TM?
anteroinferior
TM quadrant location for myringotomy and tube placement
posteroinferior
what provides general sensory innervation to the middle ear cavity?
tympanic plexus of CN IX
nerve that supplies sensation to the helix of the outer ear
auriculotemporal nerve - a branch of V3
nerve that supplies sensation to the lobe of the outer ear
greater auricular nerve - C2, C3
VERY thin bone creating the roof of the middle ear cavity
tegmen tympani
What sits on top of the tegmen tympani?
dura of the middle cranial fossa
what comes next if otitis media is not treated?
mastoiditis
swimmer’s ear
otitis externa
signs of otitis externa
pulling on auricle and/or applying pressure to the tragus increases pain
what if you see a bulging red tympanic membrane on exam?
sign of otitis media
incision to release pus from a middle ear abscess
myringotomy
complication of mastoiditis
osteomyelitis of tegmen tympani
what part of the temporal bone forms the anterior wall of the external auditory canal?
tympanic plate
what separates the middle and posterior cranial fossa?
petrous ridge of the petrous portion of the temporal bone
pain info associated with otitis media will be carried by…
tympanic plexus of CN IX
special sensory innervation to the inner ear is provided by…
vestibular and cochlear portions of CN VIII
what features are located in the posterior wall of the middle ear cavity?
mastoid air cells and the facial nerve
the concavity of the TM is pointed…
anteriorly, laterally, inferiorly
where does the transmission of sound from bone to fluid occur?
oval window
stylohyoid is innervated by…
CN VII
posterior belly of digastric is innervated by…
CN VII
muscles of facial expression are innervated by…
CN VII
innervation of the anterior belly of digastric
nerve to myohyoid
Where does the greater petrosal nerve terminate/what is it’s function?
- lacrimal gland for tear production
- nasal cavity for mucous production
describe the fibers of the deep petrosal nerve
postsynaptic sympathetic fibers that have jumped off the ICA
describe the fibers of the nerve of the pterygoid canal
postsynaptic sympathetic fibers of the deep petrosal nerve + presynaptic parasympathetic fibers of the greater petrosal nerve
greater petrosal nerve hitchhikes on what other nerve to get to the lacrimal gland and mucous glands of the nasal cavity?
V2
where does chorda tympani terminate/what is its function?
- anterior 2/3 of tongue for taste sensation
- submandibular gland for mucous production
- sublingual gland for saliva secretion
chorda tympani hitchhikes on what nerve to the floor of the mouth?
lingual nerve of V3
synaps of chorda tympani’s parasympathetic fibers occurs at which ganglion?
submandibular ganglion
synapse of greater petrosal nerve’s parasympathetic fibers occurs at which ganglion?
pterygopalatine ganglion
describe the fibers of chorda tympani
parasympathetics to the submandibular and sublingual glands
sympathetics for taste to the anterior 2/3 of the tongue
where does chorda tympani exit the skull?
petrotympanic fissure
In a lesion with facial paralysis/Bell’s palsey: if there is preserved taste function, where did the lesion occur?
distal to chorda tympani
In a lesion with facial paralysis/Bell’s palsey: with NO taste function, where did the lesion occur?
proximal to chorda tympani
If you have a lesion that is resulting in Bell’s palsey, do you also have louder hearing on one side?
yes. an infection producing Bell’s palsey also affects stapedius
Mumps has what consequence in the face?
enlarged parotid gland
parotid duct function
carries saliva from the parotid gland and dumps it into the mouth
parotid gland function
saliva synthesis and secretion
innervation of the parotid duct
lesser petrosal nerve (CN IX)
things that pass through the parotid gland
external carotid artery
retromandibular vein
major portion of facial nerve (will supply muscles of facial expression)
auriculotemporal branch of V3 (with hitchhiking secretomotor fibers from otic ganglion (IX))
parotid duct
termination of the parotid duct? (Stenson’t duct)
pierces the buccinator and ends opposite the upper second molar
6 named branches of the facial nerve to muscles of facial expression
“To Zanzibar By Motor Car”
- Temporal
- Zygomatic
- Buccal
- Maxillary
- Cervical
- Posterior Auricular
temporal branch of CN VII innervates…
upper eyelid of orbicularis occuli and superior to that
zygomatic branch of the facial nerve innervates…
the lower eyelid of orbicularis occuli
buccal branch of facial nerve innervates…
upper lip and buccinator muscle
mandibular branch of facial nerve innervates…
lower lip and chin
cervical branch of facial nerve innervates…
platysma
posterior auricular branch of facial nerve innervates…
occipitalis muscle
special sensory taste fibers going to the tongue have their soma in which ganglion?
geniculate ganglion
what defines the superficial and deep portions of the parotid gland?
passage of the facial nerve
what is the terminal branch of the nasocilliary nerve?
external nasal nerve
what branches of CN V2 carry hitchhiking fibers of CN VII to the lacrimal gland?
zygomaticofacial and zygomaticotemporal
nerve supplying sensation to the inside of the cheek
buccal branch of V3
nerve supplying sensation to the chin
mental branch of V3
named nerve supplying sensation to the tip of the nose
external nasal banch of V1
named nerve supplying sensation to the bridge of the nose
infratrochlear branch of V1
named nerve supplying sensation to the middle forehead
supratrochlear branch of V1
named nerve supplying sensation to just above the eyebrow
supraorbital branch of V1
named nerve supplying sensation to the lateral eyebrow
lacrimal branch of V1
named nerve that supplies sensation to the cheek just below the eye
infraorbital branch of V2
named nerve that supplies sensation to the temporal region
zygomaticotemporal branch of V2
named nerve that supplies sensation to the tip of cheek bone area
zygomaticofacial branch of V2
named nerve that supplies sensation to the jaw line
greater auricular nerve (C2, C3)
named nerve that supplies sensation to the ear lobe
greater auricular nerve (C2, C3)
Named nerve that supplies sensation to the proximal helix of the outer ear (concha?)
auriculotemporal branch of V3
named nerve that supplies sensation to the skin behind the ear
lesser occipital nerve (C2, C3)
named nerve that supplies sensation to the skin on the posterior head
greater occipital
frontalis muscle is innervated by…
CN VII temporal branch
occipitalis muscle is innervated by…
posterior auricular (occipital) branch of CN VII
orbicularis oris muscle is innervated by…
buccal and mandibular branches of CN VII
embryonic origin of the muscles of facial expression
2nd pharyngeal arch
5 layers of the scalp
SCALP
1. Skin
- Connective tissue
- aponeurosis (gala aponeurotica)
- Loose areaolar tissue
- pericranium
innervation of skin superficial to platysma
transverse cervical nerve
function of buccinator muscle
pushes food medially when eating, sucking on a straw.
food accumulates between teeth and gums if buccinator muscle looses nerve supply
the retromandibuolar vein is formed by the junction of what two veins?
superficial temporal vein + maxillary vein
common facial vein is formed by the junction of what two veins?
anterior division of the retromandibular vein + facial vein
the anterior division of the retromandibular vein drains into…
internal jugular vein
the posterior division of the retromandibular vein drains into the…
external jugular vein
describe the clinical significance of the danger triangle
infections of the face near the nose may spread into the cranial cavity by passing through the emmissary veins associated with the pterygoid plexus of veins (may also spread through opthalmic veins of the orbit). Opthalmic veins and emmisary veins of the pterygoid plexus will drain into the cavernous sinus.
what makes the facial nerve of newborns so vulnerable and puts them at risk for facial paralysis (especially during the birthing process)?
their skulls lack a mastoid process, so the facial nerve is not well-protected
which cranial nerve does Bell’s palsey affect?
CN VII
which muscle is important for swallowing without drooling?
orbicularis oris
which muscle plays a role in eating but NOT mastication??
buccinator
Where do the branches of CN V exit the cranial cavity?
“Standing Room Only”
V1: Superior orbital fissure
V2: foramen Rotundum
V3: foramen Ovale
function of the masseter
elevation of the mandible
function of the temporalis muscle
elevation and retraction of the mandible
innervation of the temporalis muscle
DEEP temporal nerve of V3
what is the doorway from the infratemporal fossa to the pterygopalatine fossa?
pterygomaxillary fissure
the pterygomaxillary fissure connects the infratemporal fossa to the…
pterygopalatine fossa
petrotympanic fissure
where chorda tympani exits the skull
pterygopalatine fossa
houses the pterygopalatine ganglion (in which presynaptic parasympathetic fibers of GPN synapse onto postsynaptic parasympathetic fibers)
located between the maxilla and the pterygoid process of the sphenoid bone
pterygomaxillary fissure
the doorway/connection between the infratemporal fossa and the pterygopalatine fossa
infratemporal fossa
inferior to zygomatic arch, medial to ramus of the mandible, lateral to the lateral pterygoid plate of the sphenoid bone
what exits the mental foramen?
inferior alveolar nerve
what is on the body of the mandible and holds the teeth in place?
alveolar process
what ENTERS the mandibular foramen?
inferior alveolar nerve
what does the inferior alveolar nerve supply?
sensation to lower teeth
what is the function of the lateral pterygoid muscle?
protraction and lateral grinding of the mandible
what is the function of the medial pterygoid muscle?
elevation and grinding of the mandible
does the lateral or medial pterigoid muscle have a vertical orientation?
medial pterygoid muscle
describe the differences in attachmets between the lateral and medial pterygoid muscles
Lateral: from LATERAL aspect of the lateral pterygoid plate and the inferior surface of greater wing of the sphenoid
Medial: from MEDIAL aspect of the lateral pterygoid plate and posterior surface of the maxilla
These TWO muscles contribute to the protrusion and lateral grinding motion of teeth
medial and lateral pterygoid muscles
two things that live in the pterygopalatine fossa
- branches of V2
- pterygopalatine ganglion
Contraction of pterygoid muscles on the LEFT will move the mandible…
to the RIGHT
what two branches of V3 come out between the lateral and medial pterygoid muscles in the infatemporal fossa?
- lingual
- inferior alveolar
what is the function of the lingual nerve?
general sensory to the anterior 2/3 of the tongue (chorda tympani does TASTE here and hitchhikes on the lingual nerve to the tongue)
nerve to myohyoid is a branch of what nerve?
inferior alveolar nerve
auriculoemporal nerve forms a loop around what artery?
middle meningial artery
auriculotemporal nerve runs with what artery?
superficial temporal artery
what supplies sensation to the upper teeth and mandible?
posterior superior alveolar nerve
posterior superior alveolar is a branch of what nerve
V2
8 muscles with motor innervation from V3
- anterior belly of digastric
- temporalis
- lateral pterygoid
- medial pterygoid
- masseter
- myohyoid
- tensor tympani
- tenor palati
specific innervation of anterior belly of digastric (motor)
nerve to myohyoid (branch of V3)
specific name of motor innervation to lateral pterygoid muscle
lateral pterygoid nerve (branch of V3)
speciffic innervation of medial pterygoid muscle (motor)
medial pterygoid nerve (branch of V3)
specific innervation of masseter (motor)
masseteric nerve (branch of V3)
termination of the middle meningial artery
sphenopalatine artery
nasal cavity is supplied by which artery?
sphenopalatine artery
secretomotor parasympathetic fibers to the parotid gland are supplied by what?
CN IX
how do postsynaptic parasympathetic fibers of CN IX (coming from otic ganglion) get to the parotid gland?
they hitchhike on the auriculotemporal nerve
describe the lesser petrosal nerve
presynaptic parasympathetic nerves of CN IX coming from the tympanic plexus going to the otic ganglion
lateral wall of the temporal bone
squamous portion
floor of the temporal bone
petrous portion
what artery runs on the inside of the squamous portion of the temporal bone?
middle meningeal
what comes out of foramen spinosum?
middle meningeal artery
foramen lacerum is a gap between what two things?
greater wing of the sphenoid and the petrous portion of the temporal bone
jugular foramen is a gap between what two things?
occipital bone and the petrous portion of the temporal bone
lesser petrosal nerve exits the skull where after going through the middle ear and running along the petrous portion of the temporal bone?
foramen ovale
the common carotid bifurcates what what vertebral level?
C3/C4
what is the vertebral level of the lower pharynx/larynx?
C5/C6
what holds the dens against the anterior arch of the atlas?
cruciate ligament of the atlas
what joint turns the head side to side, “no”
atlantoaxial joints
what joint nonds the head “yes”
atlantooccipital joints
what prevents over extension of the head?
anterior atlanto-occipital membrane
what prevents hyperflexion of the head?
posterior atlanto-occipital membrane
what syndromes cause laxity of the the craniovertebral ligaments?
spinal cord injury
Down’s
RA
25% of stroke occur…
in the vertebral artery
where does the vertebral artery enter the cranial cavity?
foramen magnum
right and left vertebral arteries form to become the…
basilar artery
hyoid bone sits at what vertebral level?
C3
clinical correlation of the cricothyroid ligament
important for emergency access to lower airway when the upper airway is blocked
cervical plexus includes what spinal cord levels?
C1-C4
C1-C7 exit the spinal canal above or below their respective vertebrae?
ABOVE. beginning with C8 spinal cord level, the nerves will exit above their corresponding vertebrae
motor portion of the cervical plexus
Ansa cervicalis
investing fascia of the neck contains what two muscles?
- trapezius
- SCM
which fascia layer extends laterally as the axillary sheeth?
prevertebral fascia
contents of the carotid sheath (3)
- carotid arteries
- internal jugular vein
- vagus nerve
carotid bodies are innervated by CN…
IX and X
carotid sinus are innervated by CN…
IX
carotid sinus detect…
blood pressure (baroreceptors)
carotid bodies detect…
O2 content (chemoreceptors)
this vessel pierces the investing fascia just above the clavicle
external jugular vein
4 muscles of the suboccipital triangle
- rectus capitus posterior major
- rectus capitus posterior minor (doesn’t define triangle)
- obliquus capitus inferior
obliquus capitus superior
2 important facts about the suboccipital triangle
- it is the region of passageway for the vertebral artery FROM foramen transversarium of C1, PIERCES the posterior atlanto-occipital membrane, and goes INTO the vertebral foramina on it’s way to the skull
- only area where aspects of posterior rami are seen and given names
Named posterior ramus of C1
suboccipital nerve
named posterior ramus of C2
greater occipital nerve
named posterior ramus of C3
third occipital nerve
what nerve runs on the surface of anterior scalene muscle
phrenic nerve (C3, C4, C5)
two triangles of the lateral neck
- occipital triangle (larger)
- subclavian/omoclavicular triangle (smaller)
sensory branches of the cervical plexus (and spinal roots)
- lesser occipital (C2)
- greater auricular (C2, C3)
- transverse cervical (C2, C3)
- supraclavicular (C3, C4)
which lymph nodes lie along the EJV?
superficial cervical lymph nodes
which lymph nodes lie along the IJV?
deep cervical lymph nodes
sentinel lymph node of the tonsils
jugulodigastric
sentinel lymph node of the tongue
jugulo omo-hyoid
SCM innervation
CN XI
geniohyoid innervation
C1
stylohyoid innervation
CN VII
posterior belly of digastric innervation
CN VII
anterior belly of digastric innervation
V3
thyrohyoid innervation
C1
sternothyroid innervation
C1-C3, ansa cervicalis
sternohyoid innervation
C1-C3, ansa cervicalis
omohyoid innervation
C1-C3, ansa cervicalis
spinal cord levels of superior root of ansa cervicalis
C1, C2
spinal cord levels of inferior root of ansa cervicalis
C2, C3
boundaries of the submandibular triangle
- hyoid
- anterior bellies of digastric
- myohyoid muscles (floor)
- mandibular symphysis
muscular triangle boundaries
- superior belly of omohyoid
- anterior border of SCM
- midline of the neck
carotid triangle borders
- superior belly of omohyoid
- posterior belly of digastric
- anterior border of SCM
borders of submandibular triangle
- inferior border of mandible
- anterior and posterior bellies of digastric
- mylohyoid (floor)
3 cervical ganglion and their roots
superior (C1, C2)
middle (C6)
inferior (C7)
*** NO white rami communicans
embryologic origin of the thyroid gland
foramen cecum
superior thyroid artery is a branch off the..
external carotid artery
inferior thyroid artery is a branch off the…
thyrocervical trunk
the one muscle in the suprahyoid region innervated by C1
geniohyoid
C1 innervates what 2 muscles
geniohyoid
thyrohyoid
Roots of the cervical plexus (dorsal/sensory + ventral/motor)
C1-C4
Roots of sensory branches of the cervical plexus
C2-C4
Roots of the motor branches of cervical plexus (=ansa cervicalis)
C1-C3
What nerve runs on the anterior surface of anterior scalene?
Phrenic (C3-C5)
Location of the jugulodigasctic deep cervical lymph node
Where the postior belly of the digastric crosses the internal jugular vein
Location of the Jugulo-omohyoid deep cervical lymph node
At the tendon of omohyoid
What drains to the Jugulodigastric lymph node?
Tonsils
What drains to the jugulo-omohyoid lymph node?
Tongue
What vertebral level does the cricoid cartilage sit at and what does it represent?
C6
End of the pharynx, beginning of the esophagus
Omohyoid innervation
Superior belly: superior root of ansa cervicalis
Inferior belly: inferior root of ansa cercicalis
Embryological remnant of the thyroglossal duct
Foramen cecum
Which tonsil lies between the palatoglossal and palatopharyngeal folds?
Palatine tonsil
Four intrinic tongue muscles
- Superior longitudinal
- Inferior longitudinal
- Transverse
- Vertical
What do the intrinsic tongue muscles do?
Change the shape of the tongue
(no boney attachments)
Innervation on the intrinsic tongue muscles
Hypoglossal (CNXII)
Four extrinsic muscles of the tongue
- Genioglossus
- Hyoglossus
- Styloglossus
- Palatoglossus
What do the extrinsic tongue muscles do?
Move the tongue
(they have boney attachments)
Action on palatoglossus
Lift tongue up
Action of genioglossus
Stick tongue out
Styloglossus action
Bring tongue backwards
Hyoglossus action
Move tongue down, towards bottom of oral cavity
Innervation of the extrinsic tongue muscles
All are innervated by hypoglossal nerve (CN XII), EXCEPT… palatoglossus, which is innervated by glossopharyngeal (CN IX)
What would a patient with a lesion to the hypoglossal nerve present with?
Tongue deviating TO the AFFECTED side… away from the healthy side
Taste innervation of the tongue
Anterior 2/3: CN VII via chorda tympani
Posterior 1/3: CN IX
Epiglotis/behind tongue: CN X
Somatic sensation (touch, pain) innervation of the tongue
Anterior 2/3: Lingual nerve, CN V3
Posterior 1/3: CN IX
Epiglotis/behind tongue: CN X
Arterial supply to the tongue
Lingual artery from the external carotid artery
submandibular, sublingual, and microscopic mucosal glands are innervated by what?
chorda tympani
3 structures superficial to hyoglossus muscle:
- Lingual nerve (of CN V3)
- Warton’s duct
- Hypoglossal nerve (CN IX)
2 structures deep to the hyoglossus muscle:
- Glossopharyngeal nerve (CN IX)
- lingual artery
What causes cleft palate?
failure of the mesenchymal masses in lateral palatine processes to meet and fuse…
maxillary and palatine bones to fuse in the midline as the intermaxillary and interpalatine sutures
Four soft palate muscles
- Tensor veli palatine (above)
- Levator veli palatine (above)
- Palatoglossus (below)
- Palatopharyngeous (below)
Innervation of the soft palate muscles
All are innervated by Vagus nerve (CN X), EXCEPT…
Tensor veli palatine, which is CNV3
If unilateral Vagus nerve is paralyzed, what would the patient present as?
Uvula deviating AWAY from the affected side, toward the healthy side
The Greater and Lesser Palatine Arteries come from where?
They come from the pterygopalatine fossa, and are branches of the maxillary artery (branchh of external carotid)
The Nasopalatine, Greater Palatine, and Lesser Palatine nerves contain what type of fibers?
- Somatosensory from CN V2
- Parasympathetic visceral motor from CN VII
- Sympathetics
The hard palate recieves most of its sensory innervation from terminal branches of the Maxillary nerve division of the Trigeminal nerve (CNV2), what is the acception?
Buccal nerve is a branch of the Mandibular division of CN V3, and innervates the lateral, posterior teeth
Where do you administer nerve blocks for upper and lower teeth?
Upper: multiple injections
Lower: one injection at mandibular foramen
Borders of the nasopharynx
Choana to the uvula
Borders of the oropharynx
Uvula to the epiglottis
Borders of the laryngopharynx
Epiglottis to cricoid cartilage
Anterior boundary of the nasopharynx
choana
anterior boundary of the oropharynx
palatoglossal arch
anterior boundary of the laryngopharynx
laryngeal inlet
origin of all 3 pharyngeal constrictors
pharyngeal raphe
anterior attachments of superior pharyngeal constrictor (3)
- medial pterygoid plate
- hamulus
- pterygomandibular raphe
anterior attachments of the middle pharyngeal constrictor (2)
- stylohyoid ligament
- hyoid bone
anterior attachments of the inferior pharyngeal constrictor (2)
- thyroid cartilage
- cricoid cartilage
2 layers of the pharyngeal fascia
Buccopharyngeal fascia (outside)
Pharyngobasilar fascia (inside)
Three pharyngeal lifters
- Stylopharyngeus
- Palatopharyngeus
- Salpingopharyngeus
projection of the medial end of the cartilagenous pharyngeotympanic tube is called…
torus tubarius
Mucous membrane found just inferior to the pharyngeal orifice in the nasopharynx
lebator veli palatine
lies under the mucus membrane along the arch of the torus tubarius, deep to levator veli palatine
tensor veli palatine
2 functions that levator veli palatine and tensor veli palatine do together, at the same time
- raise the soft palate
- opent the PT tube
all muscles of the palate are innervated by _____, EXCEPT _____, which is innervated by _____.
Vagus
Tensor veli palatine
V3`
all muscles of the pharynx are innervated by _____, EXCEPT _____, which is innervated by ______.
Vagus
stylopharyngeus
only motor branch of IX
Boundary between the oral cavity and the pharynx
palatoglossal fold
Three muscles originate from the styloid process
- stylohyoid
- stylopharyngeous
- styloglossus
Vertebral level of superior cervical ganglion
C2, C3
vertebral level of middle cervical ganglion
C6
vertebral level of inferior (Stellate) cervical ganglion
C7
All muscles of the larynx are innervated by _____, EXCEPT _____, which is innervated by ______.
recurrent laryngeal nerve (Vagus)
cricothyroid
superior laryngeal nerve (external branch)
8 muscles innervated by V3
- masseter
- temporalis
- medial pterygoid
- lateral pterygoid
(4 muscles of mastication)
- tensor tympani
- tensor veli palatine
(2 tensors)
- mylohyoid
- anterior belly of digastric
(2 accessory muscles of mastication)
4 tonsils from superior to inferior
PTPL
Pharyngeal
Tubal
Palatine
Lingual
Where does lymph from the tonsils generally drain to?
jugulodigastric (superior deep) lymph nodes
6 locations of superficial lymph nodes
- scattered along external jugular vein
- occipital
- posterior auricular (mastoid)
- parotid
- submandibular
- submental
3 locations of deep lymph nodes
- scattered along internal jugular vein
- jugulodigastric: at posterior belly of digastric crossing the internal jugular vein
- jugulo-omohyoid: at intermediate tendon of omohyoid
Sentinel lymph nodes primarily targeted by cancer mets
jugulodigastric
juguloomohyoid
jugulodigastric gets drainage from where?
roof of oral cavity and posterior tongue
Floor of oral cavity and anterior tongue drains to which lymph nodes…
to submental or submandibular nodes, then to deep cervical nodes
what runs through the pterygoid canal (2)
- parasympathetic greater petrosal nerve
- sympathetic deep petrosal nerves
Both >>> to pterygopalatine ganglion
maxillary and sphenoid sinuses drain properly when head is in what position?
flexed
spenoid ostium are higher than the floor of the phenoid sinues, which maes drainage in the erect position difficult
anterior and posterior ethmoidal arteries come from where?
opthalmic artery
sphenopalatine artery is the TERMINAL branch of what artery
TERMINAL branch of maxillary artery
Greater palatine artery is a branch of which artery
maxillary artery
septal branch of superior labial artery is a branch of which artery
facial artery
4 arteries of the nasal septum
- ethmoidals (from opthalmic artery)
- greater palatine artery (from maxillary artery)
- sphenopalatine artery (terminal branch of mexillary artery)
- septal branch of superior labial artery (from facial artery)
site of anastamoses of nasal arteries
Kiesselbach’s area
Nasopalatine nerve contains… (3)
- sensory fibers from V2
- parasympathetic fibers from pterygopalatine ganglion (VII)
- sympathetics from pterygopalatine ganglion
what nerves run at the very top of the nasal septum
anterior and posterior ethmoidals from V1 nasocilliary nerve
4 spaces on lateral wall of nasal cavity
- inferior nasal meatus
- middle nasal meatus
- superior nasal meatus
- spheno-ethmoidal meatus
what drains into spheno-ethmoidal meatus
sphenoid sinus
what drains into superior nasal meatus?
posterior ethmoidal sinus
what drains into middle nasal meatus?
frontal sinus
maxillary sinus
anterior ethmoidal sinus
middle ethmoidal sinus
what drains into inferior nasal meatus
nasolacrimal duct
CN V2 sensory + VII p/s + sympathetics gives rise to 5 nerves of the nasal cavity:
- superior nsal branch (on middle concha)
- inferior nasal branch (on inferior concha)
- nasopalatine nerve
- greater palatine nerve
- lesser palatine nerve
function on the nasal conchae
increase surface area of nasal canal for cleansing, warming, and humidifying incoming air
parasympathetics cause ______ of the nasal mucosal arteries
vasodilation
sympathetics cause ______ of the nasal mucosal arteries
vasoconstriction
4 sets of nasal sinuses
- frontal (2)
- maxillary (2)
- sphenoid (1 or 2)
- ethmoidal air cells (3 per side)
3 functions of sinuses
- lighten skull
- add resonance
- protect brain from temperature of inspired air
drainage of frontal sinus
anterior hiatus semilunaris through ethmoidal infundibulum
Maxillary sinus drainage
middle hiatus semilunaris through maxillary ostium
Sphenoid sinus drainage
through spheno-ethmoidal recess
ethmoidal air cell sinus drainage
- posterior ethmoidal air cells: superior nasal meatus
- middle ethmoidal air cells: semilunar hiatus >> middle nasal meatus
- anterior ethmoidal air cells: ethmoidal infundibulum >> middle nasal meatus
nasolacrimal duct drains into…
inferior nasal meatus
Maxillary, sphenoid, and poisterior ethmoidal sinuses ONLY drain when head is in ______ positoin
flexed
which sinus has the poorest drainage?
maxillary sinus: its location is lower than the drain opening
lymph from anterior nasal cavity drains to…
submandibular lymph nodes then to jugulodigastric nodes
posterior nasal cavity lymph drains to…
tonsils, then to jugulodigastric nodes
Length and thickness of the vocal cords are fixed, how do you change the tension?
- stretch the strings by rocking the thyroid back and forth
- harden the strings by contracting the muscle and stretching
2 muscles shorten the vocal cord
vocalis
thyroarytenoid
what does the cricothyroid muscle do to the vocal cords
elongate and tense the vocal cords
muscles that adduct the vocal cords (4)
- lateral cricoarytenoid
- thyroarytenoid
- oblique arytenoid
- transverse arytenoid
ONLY muscle to abduct (open) the vocal cords
posterior cricoarytenoid
muscle that pulls the epiglottis toward the arytenoid cartilages and CLOSES the larynx
aryepiglottis muscle
what is the ligament at the inferior tip of the epiglottis?
thyroepiglottic ligament
what ligament is in the glossoepiglotic fold?
hyoepiglotic ligament
the hyoepiglottic ligament is in what fold?
glossoepiglottic fold
function of the hyoepiglottic ligament
pulls the epiglottis back into its vertical position
these are spaces that hold saliva to delay the swallowing reflex
valleculae
false vocal cord is in what fold?
vestibular fold
superior laryngeal artery brances from what?
superior thyroid artery
- superior laryngeal nerve branches from what?
- and gives off what branches?
- Vagus
- internal branch and external branch
internal branch of superior laryngeal nerve’s function
sensory to vestibule
external branch of superior laryngeal nerve’s function
motor to cricothyroid
All laryngeal muscles are are innervated by _____, EXCEPT ______, which is innervated by ______.
recurrent laryngeal nerve (from vagus)
cricothyroid
external branch of superior laryngeal nerve
Sensory innervation above the true vocal cord (entire vestibule)
internal branch of superior laryngeal nerve
Sensory innervation below the true vocal cords
recurrent (inferior) laryngeal nerve