Middle Ear (week 3) Flashcards
What two branches of the External carotid artery supply blood to the External ear
Posterior Auricular and Superficial Temporal
What innervates the external ear
- Cervical Plexus - Great Auricular
- CN V3 - Auriculotemporal nerve
- CN VII, X - Small auricular branches
What branch of the Maxillary artery supplies blood to external ear
Deep Auricular
All branches of arteries that supplies blood to external ear
Deep Auricular, Superficial Temporal and Posterior Auricular
two parts that make up the tympanic membrane
Flaccid part and Tense part
Where is the flaccid part of the tympanic membrane in relation to the tense part?
Superior
What innervates the external portion of the tympanic membrane
- Cervical Plexus - Great Auricular
- CN V3 - Auriculotemporal n.
- Cn VII, X - Small auricular branches
What innervates the internal portion of the tympanic membrane
CN IX - Tympanic Plexus
What does the Tegmen Tympani do?
Separates middle ear from middle cranial fossa
What does the floor of the middle ear do?
Separates middle ear from internal jugular vein
What is in the lateral portion of the middle ear
Chorda Tympani, Tympanic membrane and Epitympanic recess
What is contained in the medial wall of the middle ear
Promontory, Tympanic Plexus, Oval (vestibular) window and Round (cochlear) window d
What is in the Anterior portion of the middle ear wall
Auditory Tube and Canal for Tensor Tympani
Which auditory ossicle is attached to the tympanic membrane?
Malleus
What are the three auditory ossicles
Incus, Malleus and Stapes
What shape does the stapes look like?
A stirrup
What shape does the malleus look like
Hammer
Two muscles in the ear
Tensor Tympani and Stapedius
Attachment of Stapedius
Pyramidal process on posterior wall to Stapes
Attachment of Tensor Tympani
Pharyngotympanic tube to the malleus
Innervation of Tensor Tympani
V3
Innervation of Stapedius
CN VII
Action of Stapedius
Decreases vibrations of stapes
Action of Tensor Tympani
Pulls malleus medially to tense tympanic membrane
Purpose of Pharyngotympanic tube
Purpose is to equalize pressure between exterior and middle ear
What three muscles are involved in opening of the pharyngotympanic tube?
Levator Veli Palitini, Tensor veli palitini and Salpingopharyngeus muscles
Which two of the three muscles are attached to the pharyngotympanic tube
Tensor Veli Palitini and Salpingopharyngeus muscles