Hearing and Balance Flashcards
Ear mass determines restriction of high/low frequencies
high
Ear stiffness determines restriction of high/low frequencies
low
What determines ear stiffness?
air pocket
What is the function of the auditory tube?
equalize pressure of inner ear and middle ear using the pharynx
Pathology of cauliflower ears
repeated tearing of ear cartilage off bone
hematoma
cartilage growth –> abnormal healing
What 4 nerves innervate the external ear
greater auricular (cervical)
lesser occipital (cervical)
auricular branch of CNX
auriculotemporal branch of V3
What is cerumen?
ear wax
What/where is cerumen secreted?
modified apocrine glands near external auditory meatus
What/where is the pars tensa?
vibratory portion of tympanic membrane–lower portion
External innervation of tympanic membrane
anterior: auriculotemporal V
posterior: auricular X
Internal innervation of tympanic membrane
tympanic branch of IX
3 ossicles
malleous
incus
stapes
Function of tensor tympani (malleous n. V3) and stapedius (facial n.)
stiffen ossicles chain
Auditory tube function
keep pressure equal between external auditory canal and middle ear space
40-55 dB
hearing loss if middle ear was completely shot
