Clinical Anatomy of the Ear Flashcards
where is the mastoid process in relation to the external acoustic meatus?
mastoid process is posterior to ear
which nerves does the temporal bone contain?
the facial and vestibulocochlear nerves
what is the Pterion?
- H-shaped suture where frontal, parietal, temporal and sphenoid meet, it is the thinnest part of the skull
what are the 2 parts of the temporal bone?
squamous part and petrous part
which bones make up the anterior cranial fossa?
frontal, ethmoid and sphenoid
which bones make up the middle cranial fossa?
sphenoid and temporal
which bones make up the posterior cranial fossa?
temporal and occipital
through which base of skull foramen does CN I pass through?
cribriform plate of ethmoid
foramen for CN II?
optic canal
foramen for CN III?
superior orbital fissure
foramen for CN IV?
superior orbital fissure
foramen for CN V1?
superior orbital fissure
foramen for CN V2?
foramen rotundum
foramen for CN V3?
foramen ovale
foramen for CN VI?
superior orbital fissure
foramen for CN VII?
internal acoustic meatus
foramen for CN VIII?
internal acoustic meatus
foramen for CN IX?
jugular foramen
foramen for CN X?
jugular foramen
foramen for CN XI?
jugular foramen
foramen for CN XII?
hypoglossal canal
function of external ear?
collects and conveys sounds waves to tympanic membrane
function of middle ear?
amplifies and conducts sound waves to the internal ear
what is the oval window?
opening into internal acoustic meatus (internal ear)
what does the internal ear convert special sensory information into?
into fluid waves then action potentials
what makes the skeleton of the external ear?
temporal bone
what type of cartilage is in the ear?
elastic
what produces earwax in the external ear?
ceruminous glands
what is the helix?
outer rim of the ear anteriorly
general sensory supply to the helix of the ear?
anterior rami of C2 and C3 spinal nerves
what is the general sensory supply to the superior parts of EAM and most of the tympanic membrane ?
CN V3
where in the outer ear does vagus nerve supply general sensory innervation to?
inferior parts of EAM and some of tympanic membrane