Ear Anatomy Flashcards
Name the part of the ear that collects sound waves and funnels them into the external acoustic meatus.
Pinna (auricle)
Name cranial nerve VII.
Facial nerve
Name the artery that lies anterior to the tragus.
Superficial temporal artery
What is the main function of the tympanic cavity?
Conducts sound waves in the air towards the fluid-filled cavities of the inner ear.
What is the role of the tensor tympani muscle?
Dampens sound by reducing vibrations of the tympanic membrane.
Which cranial nerve innervates the tensor tympani muscle?
CN V3
What does the stapedius muscle do?
Dampens sound by reducing vibrations of stapes on oval window.
Which cranial nerve innervates the stapedius muscle?
CN VII
Which muscles help to equalise pressure in the ear?
Palate muscles
Which cranial nerve supplies the otitis media?
CN IX
What can cause osteomyelitis in the ear?
Infection or inflammation of the mastoid
What is the bony labyrinth filled with?
Peri lymph
Similar to extracellular fluid
What is the membranous labyrinth filled with?
Endo lymph
Similar to intracellular fluid
Where is the organ of Corti located?
On the basilar membrane of the cochlear duct
Name the two parts that the cochlear canal is divided into.
Scala vestibuli
Scala tympani
What do the utricle and saccule detect?
Linear movement change
Utricle (horizontal)
Saccule (vertical)
Name CN VIII
Vestibulocochlear nerve
Where does the labyrinthine artery branch from?
The anterior inferior cerebellar artery
What are some symptoms of facial nerve dysfunction?
Dry eyes Dry mucosa Lack of taste anterior 2/3rds of the tongue Dry mouth Facial paralysis
Which cranial nerve supplies the posterior 1/3rd of the tongue?
CN IX
Which cranial nerve supplies the anterior 2/3rds of the tongue?
CN V3 and CN VII
What are causes of reffered otalgia from the facial nerve (CN VII)?
Geniculate herpes
Ramsay Hunt syndrome linked to facial palsy
Nasal pathology including foreign bodies
Sphenoid or ethmoid sinus pathology
What are causes of reffered otalgia from the glossopharyngeal nerve (CN IX)?
Tonsillitis or quinsy
Post-tonsilectomy
Carcinoma at the base (posterior 1/3) of the tongue
Neuralgia of the glossopharyngeal nerve
What are causes of referred otalgia from the vagus nerve (CN X)?
Foreign body in piriform fossa
Carcinoma or the piriform fossa
Carcinoma of the larynx
Post-cricoid carcinoma
Sepsis - piriform abscess
