ENT - 208 Flashcards
What are the functions of the ear?
- To collect sound from the environment, amplify it and convert it into neural impulses.
- Contribute to detection of gravity
- Detect movement of the head and body
- Stabilise vision
Name the parts of the outer ear
Pinna Ear Canal Lobule Helix & antihelix Tragus
Name the constituents of the middle ear
Ear drum, ossicles, facial nerve, auditory tube
Name the parts of the inner ear
Cochlea, semicircular canals, utricle, saccule
What are the ossicles?
Small bones of the middle ear - Malleus, Incus, Stapes
Outer and middle ear pathologies/problems cause what kind of deafness?
Conductive deafness
Inner ear problems causes what kind of deafness?
Sensorineural
Give some examples of disorders of the outer and middle ear
- Perforations and retractions
- Cholesteatoma
- Otosclerosis
- Glue ear
- Otitis externa
What is the function of the outer ear?
Sound amplification
What kind of abnormalities can affect the pinna?
Deformed pinna, canal atresia, pinnal atresia
What is the medical term for surfer’s ear? What is surfer’s ear?
Exostoses. This is bone growth that can block the ear canal
Which ossicle is the ear drum attached to?
The malleus
What can cause ear drum perforations?
Infection, trauma, surgery.
How are perforations usually treated?
The normally aren’t. Some might require a hearing aid or surgery but this is rare
Name a common cause of ear drum retraction
Glue ear
What does glue ear predispose to>
Acute suppurative otitis media
What is a cholesteatoma?
Skin in the middle ear, caused by a combination of normal migration and abnormal ear pressure (-ve middle ear pulls pars flaccida inwards)
What is the role of the eustachian tube and where does it run to/from?
It runs from the nasopharynx to the middle ear. It is responsible for maintaining atmospheric air pressure within the middle ear.
- Conductive hearing loss
- Foul, green discharge,
- Painless
- Complications e.g. facial N paralysis, meningitis, mastoid abscess, brain abscess
These are all characteristics of WHAT?
Cholesteatoma
What is otosclerosis?
Abnormal bone growth near the middle ear -> at the fissula ante finestram. This causes ankylosis of footplate and poorer sound transmission to cochlea.
Results in conductive hearing loss
What are the treatment options for otosclerosis?
Hearing aid -> these are v. helpful
Surgery -> piston placed through stapedotomy and wire put around incus
Name some treatment options for glue ear
Conservative ‘watch and wait’
Grommets
Hearing aid
Name some disorders of the inner ear
Presbyacusis Noise damage Acoustic neuroma Vestibular syndromes (e.g. meniere's) Vestibular neuritis (e.g. BPPV)
What is BPPV?
Benign paroxysmal positional vertigo
