ENT Flashcards
what CN gives you sense of smell (olfaction)
CN 1 - the olfactory nerve
what supples somatic sensory innervation for olfaction
top 1/2 of nose = CN V1 - ophthalmic division
bottom 1/2 of nose = CN V2 - maxillary division
which artery does the maxillary and facial artery originate from
external carotid
the ophthalmic artery is a branch of which artery
internal carotid
what is kiesselbach’s area
a site of anastomoses between arterial contributions, it is the cause of nose bleeds
located anterioinferiorly on nasal septum
what do conchae do
cause turbulent airflow through nasal cavity.
this increases the opportunity for humidifying, filtering and warming air
what are each sinus lined by
respiratory epithelium
what is the thinnest part of skull called
pterion
its an ‘H’ shaped suture between the frontal, parietal, temporal and sphenoid bone
sensory nerve supply to the external surface of the tympanic membrane
CN V3 mostly
BUT
also some CNX (vagus!)
sensory nerve supply to the internal surface of the tympanic membrane
CN 9 (glossopharyngeal)
what does the glossopharyngeal nerve supply sensory nerve supply to and why is this significant
middle ear cavity
Eustachian tube
naso and oro pharynx
tonsils
you can get referred pain from nasopharynx to middle ear
why tonsillitis and pharyngitis can cause earache
what are the 3 bones of the middle ear
malleus
incus
stapes
what are the 2 muscles of middle ear and what are they innervated by
stapedius - CN 7 (facial)
tensor tympani - CN V3
what is the chorda tympani
a branch of the facial nerve
responsible for taste on the anterior 2/3rds of tongue
parasympathetic nerve supply to submandibular and sublingual glands
innervation of stapedus muscle
chorda tympani
what is the purpose of the stapedus muscle
reduces movement of stapes to protect internal ear from excessive noise
where does octic capsule sit
in the temporal bone
what does octic capsule contain inside
cochlea, semi circular canals and vestibule
the semicircular canals are for balance. yes?
yes
what part of the vestibular apparatus detects angular movement change
utricle (horizontal) and saccule (vertical)
what nerve supples taste to posterior 1/3 of tongue
CN 9 (glossopharyngeal)
what’s the innervation of submandibular and sublingual salivary glands
CN 7 (facial)
what’s the innervation of parotid salivary gland
CN 9 (glossopharyngeal)
innervation of the anterior 2/3 of tongue
general sensory = CN V3 (mandibular)
taste = CN 7 (facial)
innervation of posterior 1/3 of tongue
general sensory and taste = CN IX (glossopharyngeal)
what CN does sticking your tongue out test
CN 7 - facial nerve
the tongue will point towards the side of CN damage
what is the innervation of all the muscles of the soft palate
the VAGUS nerve (CN10)
except the tensor veil palatine - CN V3
what CN does asking px to say ‘AHHHH” test
CN10 - VAGUS nerve
in the case of nerve damage, uvula will be pulled AWAY from the damaged side by the functioning side
what nerve are the muscles of the pharynx innervated by
CN10 - VAGUS nerve
except the stylopharyngeus - innervated by CN 9 - glossopharyngeal
in a laryngoscopy/intubation, what structure is the blade pressed against
the vallecula
what nerve innervates the intrinsic muscles of larynx
the inferior laryngeal nerve - a branch of the vagus nerve
the recurrent laryngeal nerve becomes the inferior laryngeal nerve at the level of the cricothyroid joint
which sinus is predisposed to infection
the maxillary sinus - the ostium is located superior to the cavity
this means the cilia must work against gravity to empty the sinus
what nerve provides sensation to the sinuses
sensation is provided by CN V1 and V2
what nerve conducts APs from the semicircular ducts to the brainstem?
the vestibular nerve
where are both the cochlear duct and the semicircular duct located
within the membranous labyrinth
the membranous labyrinth is suspended within the bony labyrinth by perilymph
what are semicircular canals and what are they filled with
they are interlinked ballon like structures within the semicircular canals
they are filled with ENDOLYMPH
how long is the lifespan of a tastebud and how are they replaced
they have a lifespan of around 10 days
they are replaced from basal cells within the taste bud, which differentiate into taste buds
where do the majority of taste buds sit
the papillae of the tongue
name the 4 types of papillae
- filiform
- fungiform
- vallate
- follate
which papillae is the only one not to contain taste buds
filiform
which nerve allows afferent taste nerve fibres to reach brainstem
ant 2/3 of tongue - the chorda tympani branch of facial nerve
post 1/3 of tongue - glossopharyngeal
epiglottis and pharynx - vagus nerve
main innervations of the pinna
facial nerve (CN VII) mandibular branch of the trigeminal nerve
