Ear

Question 1

Auricle

Answer 1

elastic cartilage + skin
concha, helix and tragus
Muscle innervation: facial nerve
Blood supply: anterior auricular, posterior auricular

Question 2

External acoustic meatus

Answer 2

S shaped
between auricle and tympanic membrane
lateral 1/3 cartilaginous, glands produce earwax
medial 2/3 bony

Question 3

Tympanic membrane

Answer 3

oval, semitansparent
oscillate in respons to sound waves
pars flaccida, pars tensa
malleolar stria, umbo, malleolar prominence
4 quadrants: anterosuperior, anteroinferior, posteroinferior, posterosuperior
Innervation: auricotemporal, glossopharyngeal

Question 4

Medial wall of tympanic cavity

Answer 4

promontory
oval window
round window
prominence of facial canal
prominence of lateral semicircular canal
inlet of mastoid antrum
tympanic sinus
sulcus promontory
opening of auditory tube
tensor tympani m.

Question 5

Posterior wall of tympanic cavity

Answer 5

antrum mastoideum
fossa incudis
eminentia pyramidalis
canaliculus chordae tympani
facial canal

Question 6

Inferior wall of tympanic cavity

Answer 6

jugular fossa
styloid process
foramen of tympanic canaliculus

Question 7

Superior wall of tympanic cavity

Answer 7

tegment tympani
temporal bone
groove for minor and major petrosal nerve

Question 8

Anterior wall of tympanic cavity

Answer 8

carotid canal
opening of auditory tube
tensor tympani m.
canaliculi caroticotympanici

Question 9

Lateral wall of tympanic cavity

Answer 9

tympanic membrane
epitympanic recess
manubrium mallei
chorda tympani
anulus fibrocartilagineus

Question 10

Content of tympanic cavity

Answer 10

auditory ossicles
nerves: 7th, 9th and 10th cranial nerves, sympathetic fibers
Vessels
Muscles: tensor tympani m., stapedius m.

Question 11

Pharyngotympanic tube

Answer 11

posterior half bony, anterior half cartilaginous and membranous
medial lip of cartilage- torus tubarius
Muscles: salpingopharyngeal, levator veli palatini, tensor veli palatini
Function: equalize air pressure

Question 12

Endolymphatic spaces

Answer 12

utriculus
sacculus
ductus semicirculares
ductus cochlearis

Question 13

Perilymphatic spaces

Answer 13

membranous and bony labyrinth
scala vestibuli and scala tympani
vestibulum
canales semicirculares
cochlea

Question 14

Corticolymphatic spaces

Answer 14

organ of Corti

Question 15

Semicircular canals

Answer 15

Anterior semicircular canal:
-perpendicular to long axis of pyramid
Lateral semicircular canal:
-smallest canal
-closer to horizontal plane
Posterior semicircular canal:
-parallel with the long axis of pyramid

Question 16

Vestibule

Answer 16

Lateral wall: oval window
Medial wall: sperical recess, elliptical recess, cochlear recess, vestibular aqueduct
Posterior wall: five openings to semicircular canals
Anterior wall: elliptical opening to scalavestibuli of cochlea

Question 17

Structures passing through fundus of internal acoustic meatus

Answer 17

1. Facial area: facial nerve and n.intermedius
2. Cochlear area: cochlear nerve, labyrinthine artery and vein
3. Sup. vestibular area: utriculoampullar nerve
4. Inf. vestibular area: saccular nerve
5. Foramen singulare: posterior ampullar nerve

Question 18

Hearing

Answer 18

vibration of tympanic membrane - vibration of stapes - pressure waves of perilymph - displacement of basilar membrane - shear between hair cells and tectorial membrane - bending of stereo cilia -> electrical signal

Question 19

Blood supply of bony labyrinth

Answer 19

Middle meningeal artery
Ascending pharyngeal artery
Internal carotid artery

Question 20

Blood supply of membranous labyrinth

Answer 20

labyrinthine artery -> common cochlear / ant. vestibular -> spiral / vestibulocochlear

Question 21

Lateral bending of stereo cilia

Answer 21

opening of cation channels - K+ (Ca2+) influx - depolarization - opening of voltage sensitive Ca2+ channels - release of glutamate - triggering action potential in afferent fiber

Question 22

Medial bending of stereo cilia

Answer 22

decrease in cation channel conductance - hyper polarization