Ear Flashcards
Identify the indicated features of the external ear
What two arteries supply the external ear?
Superficial temporal artery and vein
posterior auricular artey and vein
What two nerves supply sensation to the ear pinna?
auriculotemporal (anterosuperior)
great auricular (posteroinferior)
What is the external auditory canal composed of?
Until where is it lined with skin?
1/3 cartilage
2/3 bone
lined with skin until lateral surface tympanic membrane (sits obliquely)
How to physicians manipulate the pinna to get a better view of the tympanic membrane?
up and back
In addition to posterior auricular and superficial temporal, which artery supplies blood to the external auditory canal?
deep auricular off of the maxillary
What nerves supply sensation to the external auditory canal?
auricular temporal (mandibular division V3)
and auricular branch of vagus nerve (X)
What is the name of the space medial to the tympanic membrane?
What is the space superior to this space?
tympanic cavity
epitympanic recess
What is the middle ear continuous with posteriorly?
mastoid air cells
How is sensory innervation supplied to the middle ear cavity?
tympanic plexus via glossopharyngeal
Identify the indicated features of the middle ear cavity
The tip of the malleus is located where on the tympanic membrane?
What impact does this have on the shape of the membrane?
umbo
makes is conves to the middle ear and concave to to the external auditory canal
Identiy the indicated features of a healthy tympanic membrane as observed from an otoscope
Identify the indicated features of the middle ear cavity from a lateral perspective
In what direction does the facial nerve interact with the middl ear cavity?
middle to posterior
What are the names of the middl ear bones shown in the image?
the yellow articulates with what feature?
- blue: malleus
- green: incus
- yellow: stapes
- articulates with oval window (vibrades it)
Identify the indicated features of the middle ear bones.
ossification of which joint is a common cause of diminished sound
Identify the following criteria for the tensor tympani muscle and the stapedius muscle
direction they enter the middle ear cavity
attachment points
- Tensor tympani
- anteromedial direction
- Attachments
- maleus
- auditory tube
- Innervation
- mandibular nerve
- Function
- reduce vibration of the ossicles/sound prodution in the cochlea
- stapedius
- posterior direction
- attachment
- stapes
- Function
- mitigate sound
- innervation
- nerve to the stapedius from the facial, when you hear a loud sound, reduce the vibration on the oval window
Identify the branches of the facial nerve as it enters the middle ear cavity
draw these relationships
Identify the indicated featrures of the cochlea
What is the name of the membranous, bony canal system that spirals to the apex of the cochlea?
What is the name of of the apex? What connects here?
What is the name of the canal system that brings carries the infor back out to the round window?
What is sandwitched between?
scala vestibuli
hlicotrema (connection scala vestibuli and scala tympani)
scala tympani
chochlear duct
What structures are found within the cochlear duct?
- spiral organ
- hair fibers that change shape and transmit fibers to create the cochlear nerve
What sensation can occur due to problems with the tympanic membrane? Why is this?
you can get nausea, because the vagus provides GI parasympathetic innervation as well as sensatin of the external auditory canal
