Ear and Auditory Tube Flashcards
What innervates the sup. and post. aspect of the external acoutic meatus?
CNX
Which middle ear bone connects directly to the tympanic membrane?
Malleus
What are the muscles that act on the bones of the middle ear? Which nerve innervates them?
Stapedius (CNVII)
Tensor tympani (CNV)
What is the name of the glands in the ear that produce wax?
Cerumen
What are the names of the three ossicles?
Stapes
Incus
Malleus
What is important about the epitympanic recess?
It communicates to some areas of the mastoid therefore infections of the middle ear can spread there and be difficult to drain
What is the chorda tympani?
A branch of the facial nerve that travels through the middle ear. Innervates the salivary glands and tongue
What are the main features of the bone labyrinth?
Swirled cochlea and three semicircular canals connected by the vestibule
Which labyrinth contains perilymph?
The bony labyrinth
How does the tympanic membrane transmit sound?
It vibrates at the same freq and amplitude of the sound waves that impact upon it
What are the major parts of the auricle?
The helix
Tragus
Lobule
Ear Canal
What is the function of the auricle of the ear?
Collect sound and localise it
What is the function of the auditory tube?
Pressure equilisation between the middle ear and nasopharynx
What are the two windows in the middle ear?
Round window
Oval window
T/F the membranous labyrinth contains perilymph
False, it contains endolymph
What is the function of the ampulla in the inner ear?
They are fluid filled sacks with sensory receptors for dynamic equilibrium for the sensation of head movements
What nerve supplies the ant. and sup. wall of the external acoutic meatus? Why is it important?
Auriculotemporal nerve (a branch of the mandibular nerve of CNV)
Ear pain can be referred to the jaw
What is the function of the bones of the middle ear?
Vibrate to transmit sounds into the inner ear
How do the muscles of the middle ear dampen sound?
Tensing to prevent the ossicles from vibrating as much
What is the difference between the bony labyrinth and membranous labyrinth?
The bony labyrinth contains the membranous labyrinth inside it
Where is the inner ear located?
In a potential shape in the petrous part of the temporal bone
What are the bones of the middle ear called?
Ossicles
What is the cone of light of the tympanic membrane and why is it important?
The cone of light will appear if light is shined on the membrane.
It will appear different if there is pressure behind the membrane
Which artery runs close to the middle ear and what is the implication of its presence?
Internal carotid artery
Throbbing when there is fluid in the middle ear
