ILE HEARING AID DISPENSER EXAM REVIEW - WRITTEN EXAM 100% GRADED A
4 views 0 purchase
Course
Hearing aid dispenser
Institution
Hearing Aid Dispenser
ILE HEARING AID DISPENSER EXAM REVIEW - WRITTEN EXAM 100% GRADED A
ILE HEARING AID DISPENSER EXAM REVIEW - WRITTEN EXAM 100% GRADED A
REAL EXAM DEFINITIONS FOR SUCCESS GUARANTEED
ILE HEARING AID DISPENSER EXAM
REVIEW - WRITTEN EXAM 100%
GRADED A
db loss of a perforation of TM - 10-15db loss
procedure done to fix perforation - tympanoplasty or myringoplasty
monomeric spots - looks like a hole in TM, but reflects light like a mirror. holes that have healed.
aka "mirror membranes"
average dimentions of an adult eardrum - 2.3-2.9cm in length, .7cm in diameters
pars tensa - lower 4/5 of TM and tight
pars flaccida - upper 1/5 of TM and flaccid
otis externa - "swimmers ear" - inflammation of the walls of the EAM. will not cause loss unless
swelling blocks canal. treat: warm salt water, drying it, topical antibiotics
polyps - masses of tissue that grow outward from a surface
cholesteatoma - non-cancerous tumor in the middle ear. oderous discharge. sometimes perforates
upper TM. invasions of skin into the middle ear - sac of concentric rings of protein. causes
conductive loss. most dangerous pathology.
enlarged canal - result of ear surgery. often have no ear drum or ossicular chain. need approval of
physician before fitting
tympanosclerosis - white, chalky calcium deposits caused by degeneration of tissue on eardrum,
thicking and scarring from peforations and infections
epitympanic cavity - attic of middle ear. allows air into mastoid cells of temporal bone. branches
several nerves
incudotapedial junction - top of incus to head of stapes
annular ligament - footplate of stapes that is held in the oval window
speed of sound - 700mph or 340 m/s (4x as fast through water, 14x as fast through steel)
, reflection - is an echo or a reverberation
reverberation - often in a small room, 17m or less, reverbs can mask high frequencies
echo - heard and perceived later than original sound (more than 1/10s after)
absorption - aborbs sound. can improve environments w/ reflection or reverb. better in warmth
and moist
diffraction - sharpness in the change in direction of sound, bending. high diffraction=bigger
wavelengths (low freq)
refraction - sound passes through one medium to another, change in speed and wavelength
infrasound - below audible range of 20 Hz
ultrasound - above audible range of 20K Hz
octave - anytime the frequency doubles. f(2) = on octave; f(3)= two octaves
faintest sound a human can hear - 10 ^ -16 watts/cm^2 and pressure of .0002 dynes/cm^2
threshold of pain - 1000 dynes/cm^2
when SPL levels double how many db levels increase? - 6 db
db HL expresses: - threshold levels
db SPL expresses: - voices or environmental sounds
pinna function: - gather sound, aid in localization, enahnce high freq bw 2k-5k hz
aperture - entrance to canal, first bend
isthmus - narrowing of canal
resonance frequency - between 3k-4k (or 2k-5k in other studies) range, natural boost of 10db,
when combined w/ high freq enhancement of the pinna - 15-20 db increase around 2700 hz
stenosis - narrowing of ear canal
atresia - absense of an ear canal
microtia - smaller than normal pinna
anotia - absence of one or both external ears
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller ROSELYNE. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $10.99. You're not tied to anything after your purchase.