06.1 The Ear Flashcards
What does the external ear consist of?
Pinna
External auditory canal
Tympanic membrane
What is a pinna haematoma?
Haematoma between the cartilage and perichondrium preventing the oxygenation of tissue
What can a pinna haematoma lead to if not treated quickly?
Cauliflower ear
What are the contents of the middle ear?
Ossicles+muscles
Eustachian tube
Mastoid air cells
Cranial nerve VII - Chorda Tympani
What are the 3 ossicles called?
Malleus
Incus
Stapes
What are the ossicle muscles innervated by?
Tensor tympani - CNV
Stapedius - CNVII
What do the ossicle muscles do in response to loud noise?
Contract so that no sound is propagated forward to protect the inner ear
What conditions can occur in the middle ear?
Acute otitis media (w. or w.out effusion)
Cholesteatoma
What is a cholesteatoma?
Dead cells accumulating due to negative middle ear pressure
Lytic enzymes erode middle ear and bone
What happens if the chorda tympani is damaged?
Loss of special sensation of the anterior 2/3 of tongue
What does the inner ear consist of?
Cochlear
Vestibular
What is the vestibular compartment for?
Balance
What is the cochlear compartment for?
Hearing
What is benign positional paroxysmal vertigo?
Displacement of cells in the vestibular compartment
Vertigo lasts for a few seconds upon turning head
What is Meniere’s disease?
Vertigo, hearing loss, tinnitus due to fluctuations in the production of endolymph fluid (endolymphatic hydrops)
