Ear Flashcards
Why is otitis media more common in infants than adults?
Infant auditory tubes are horizontal and cannot drain fluid and mucous from the middle ear effectively leaving it prone to infection, adults’ tubes are pointed down and thus drain well
Where does the auditory tube drain to?
Nasopharynx
Where does the tensor tympani m insert into the malleus?
Manubrium of the malleus
What landmark notates the sharp posterior turn of the facial n in the middle ear?
Geniculate ganglion
What is otosclerosis?
Scaring or ossification of the small joints between the ossicles that causes hearing loss because vibrations are no longer properly conducted, genetic
What innervates tensor tympani m? Stapedius m? What do they do?
Mandibular n (V3)
Facial n
TT pulls the tympanic membrane tight to prevent vibration conduction, while Stapedius yanks on the neck of the stapes pulling it out of the fenestra vestibuli
What are the R’s in the semicircular duct ampullas and what do they detect?
Crista AAAAmpullaris
Detect AAAAngular acceleration of head
What are the R’s in the saccule and utircle? What do they detect?
Maculas
Saccule version detects low-frequency vibrations (sac.. Man’s low voice..)
Utricle version detects linear acceleration
Thrombosis of what a leads to vertigo, nausea, and inner ear abnormalities?
Labyrinthine a
What forms the endolymphatic duct of the ear?
Utricular and saccular ducts coming together
What part of the vestibule communicates with the semicircular ducts?
Utricle
Prolonged exposure to loud noises can damage what?
Organ of Corti
What blood vessels are associated with an auricular hematoma? If not treated immediately, what can result?
Superficial temporal a, posterior auricular a
Permanent disfiguration of the auricle/pinna called cauliflower ear
Where are otoliths located? What do they do?
Saccule and utricle
Shift upon stirring of the endolymph from movement.. Shift happens inside an otolithic membrane, this displaces the kinocilium and stereocilia mounted on hair cells
Which cilia type rests on a plate and which doesn’t? Why?
Stereocilia rest on a plate while the kinocilium doesn’t
The kinocilium dips and deforms the plasma membrane causing a depolarization
