Audiometry Flashcards
what is human auditory range
20 - 20,000 HZ
what is conversational vocal range
250 - 4,000 HZ
what does 0 db represent
normal - sound that individuals with the best hearing should detect 50% of the time
what is normal hearing for adults and children
adults - <25 db
children - <15 db
how do we grade hearing loss
mild - 25-40db
moderate - 40-65db
severe - 65-90db
profound - > 90db
how do we perform audiometry
check hearing at 1,000 HZ
check hearing at 2,000 - 3,000 - 4,000 - 6,000 - 8,000
then retest at 1,000 - before testing 500 - 250
when response to tone is not heard in an ascending series, present a tone that is __ until response is head
when response to tone is heard, present a tone that is ___ , then perform another ascending series
not head - increase 5 db
heard - decrease 10 db
what is threshold hearing
lowest decibel hearing level at which heard responses occur in at least 1/2 the series of ascending trials
minimum number of responses to determine threshold hearing is 2/3 presentations at a single db level
what hearing condition would result in the highest frequency lost on the audiometry scale
sensory neuro loss
how does the audiometry appear if there is a conductive loss
what are some causes
normal bone conduction
air conduction decrease by 10db
causes cerumen object in canal middle ear infection middle ear effusion perforated tympanum ossicle abnormality
what hearing condition has the lowest frequency lost on the audiometry scale
conductive loss
how does the audiometry appear if there is a sensory neural loss
what are some causes
bone and air conduction are within 10db of normal
causes presbycusis meniere disease acoustic neuroma noise induced hearing loss
what are clinical features of acoustic neuroma
slow growing benign tumor usually in internal auditory meatus
hearing loss
ringing in ears - tinnitus
unsteadiness
balance issues
what are the clinical features of prebycusis
progressive, bilateral hearing loss with age
after age 50
due to structure changes of organs of hearing - degeneration of hair cells, change in basilar membrane, leads to decreased hearing loss at HIGH tones and decreased ability to discriminate HIGH pitches
eventually LOW pitch sounds will become harder to hear as well
what are the clinical features of menieres disease
distended endolymph
hearing loss that changes
ringing in ears - tinnitus
rotatory dizziness - vertigo
fullness in the ears
