Week 3 - The ears Flashcards
what are 2 muscles found within the ear and which one do you see on a model?
tensor tympani
stapedius
you will only see tensor tympani
what is the nerve innervation of tensor tympani and stapedius muscles?
stapedius = maxillary V2
tensor tympani = mandibular V3
what is the function of the stapedius and tensor tympani?
they pull on the stapes and tympanic membrane to dampen sound i.e. when chewing or when someone shouts in your ear, as to protect your ear
what 2 areas of the body does the middle air communicate with?
the nasopharynx via the eustachian tube
the mastoid air cells via audits
within the inner ear, what are the bone lined chambers known as?
the bony labyrinth
what type of lymph is found within the bony and membraneous labyrinth?
bony labyrinth = perilymph
membranous = endolymph
what nerve is found attached to the cochlear and what does it enter via?
the vestibulococchlear nerve CN VIII which enters via the internal acoustic foramen
what nerve innervates the middle ear?
the facial nerve
what nerve innervates the inner ear?
the vestibulococchlear nerve
through which foramina does the facial nerve exit the posterior cranial fossa?
through the internal acoustic foramen
where does the facial nerve run in the middle ear?
it runs along a canal on the medial wall of the middle ear cavity called the facial canal
when the facial nerve is in the middle ear, what branch does it give off?
chord tympani
what does the chord tympani supplies parasympathetic fibres to?
submandibular & sublingual salivary glands
parotid gland receives innervation from the glossopharyngeal
what does the chord tympani supply sympathetic fibres to?
anterior 2/3rds of the tongue for taste
what are the different groups of nodes which drain lymph from the face and scalp?
buccal submental submandibular mastoid parotid occipital
