12: Hearing and Equilibrium (Lab)

consisting of the pinna and the external auditory canal

Outer ear

entire outside part

Pinna(auricle)

External acoustic canal

the bottom piece

Lobule

blue arrow

Tympanic membrane

the chamber between the eardrum and cochlea that has the bones and auditory tube

Middle ear

ossicles

hammer, connects directly to the tympanic membrane

Malleus

anvil, black arrow

Incus

stirrup, green arrow

Stapes

red outline

Auditory tube

Very easy, just for clarity, green section

Inner ear

What structure is underneath the structure pointed at?

Oval window

blue circle

Round window

Blue section

Round window

the hard shell surrounding the entire thing, has perilymph fluid inside

bony labyrinth

soft shell, has endolymph inside

Membranous labyrinth

yellow arrow

Vestibulocochlear nerve(VIII)

for hearing

Cochlear nerve branch

for balance

Vestibular nerve branch

the entirety of the circled area

Vestibular apparatus

Rings

Semicircular canals

The clear section, has endolymph inside

Semicircular ducts

The thin blue section

Semicircular ducts

light blue bulb

Ampulla

Inside the ampulla, the hill that goes up (has the star)

Cristae ampullaris

What is the microscope pointing to? (the whole mass)

Cristae ampullaris

What is A pointing to?

Cupula

Yellow boxed arrow

Cupula

What is B pointing to

(Crista) Hair cells

Its obvious but just so you know, the hair cells are right before the cupula

(Crista) hair cells

Purple arrow (think "south")

Saccule

Red arrow (think "up")

Utricle

Inside the Utricle and saccule

Maculae

what is this in histology?

Maculae

Red highlighted area

Otolithic membrane

Green arrow, the white area

Otolithic membrane

Green highlighted area

otoliths

Blue arrow, the pink little dots

Otoliths

Blue highlighted area

(maculae) hair cells

White arrow, all of the cells in this layer

(Maculae) hair cells

Snail

Cochlea

Vestibular duct(scala vestibuli)

Vestibular duct(scala vestibuli)

Tympanic duct(scala tympani)

Tympanic duct(scala tympani)

Cochlear duct(scala media)

Cochlear duct(scala media)

Vestibular membrane

Vestibular membrane

Basilar membrane

Black arrow(without the O), flat pink layer

Basilar membrane

Spiral organ(Organ of corti)

The entirety of the specific area being pointed at

Organ of corti

Tectorial membrane

Blue arrow

Tectorial membrane

(Organ of corti) Hair cells

Green arrow

(Organ of corti) Hair cells

What test uses a tuning fork that you place on your head to see if you have hearing loss in one ear?

Weber test

Which test uses a tuning fork that you place behind your ear, then in front of your ear to see if you can still hear it?

Rinne test

Which test do you spin in a chair to test vestibular ocular reflex and see if someone has nystagmus? (Nystagmus is a normal response, NO nystagmus is an abnormality)

Barany test

What is nystagmus?

Involuntary rapid eye movement

What test is used to check for equilibrium/balance by having the patient close their eyes and stand still?

Romberg test

What areas of the inner ear contain perilymph?

Vestibular duct (Scala vestibuli), Tympanic duct (Scala tympani), inside bony labyrinth

What areas of the inner ear contain endolymph?

Cochlear duct (Scala media), inside membranous labyrinth

What does it mean if someone does the weber test and one ear hears the frequency louder/quieter than the other?

Potential conductive (loud) or sensorineural (quiet) hearing loss, need to preform the Rinne test to determine which.

What does it mean on a Rinne test if the sound you hear when you touch the bone is louder than when it is in front of the ear?

Conductive hearing loss in the ear, need to test other ear if it is the same.

What does it mean on a Rinne test if the sound you hear when you touch the bone is quieter than when it is in front of the ear?

Normal hearing, need to test both ears and preform the weber test again to rule out if it sensorineural.

After conducting a Rinne test with no abnormalities, you perform the weber test again to check what?

To check if the patient has sensorineural hearing loss. This would be indicated by uneven hearing when preforming the weber test after no abnormalities with the Rinne test

function of OHC

cochlear tuning

function in ICH

what we hear as sound/vibration

conductive deafness

any condition that interferes with the transmission of vibrations to the inner ear

sensorineural deafness

death of hair cells or any of the nervous elements from the cochlear nerve to brain tissue that is concerned with hearing (VIII)