Aud & Vestib Disorders Flashcards
What is an ABR? What does it assess? What is one clinical app of it?
It is used to assess the neural auditory pathway. The ABR tests and assesses the electrical potentials generated by the auditory neural pathway and it is an electrophysiologic test called an auditory evoked potential. We clinically use waves 1, 3, and 5 and as intensity decreases latency increases.
To diagnose ANSD
To confirm results of behavioral tests & establish site of lesion
How do we know OAEs are a measure of OHC fxn? What are different stimuli used for TEOAE and DPOAE?
Absence or damage of OHCs is associated with absence of OAEs further supporting the hypothesis that OAEs are generated by OHCs
TEOAE: brief acoustic stimulus (click or tone burst)
DPOAE: Simultaneously presented pure-tones of two appropriate frequencies (fi & f2) presented at two intensity levels (L1 & L2)
2f1-f2 elicits the best DPOAEs in humans
Baby failed screening and the audiologist did ABR and diagnosed sensorineural HL. 3 months later had normal hearing and passed.
What could have been done to cross check the loss?
What could have been the cause of the fail?
OAEs
Neuromaturation
What disorder should you not use alternating clicks to determine?
ANSD
A decrease in intensity should also cause a decrease in latency
f
CM are produced by OHC
t
Actual hearing threshold is typically ~10 to 15 dB HL better than the ABR threshold
t
normative Peak Latency Values at 80dB nHL
Wave I: 1.5 ms (mean)
(SD = + 0.25 ms)
Wave II: 2.6 ms (mean)
(SD = + 0.25 ms)
Wave III: 3.7 ms (mean)
(SD = + 0.25 ms)
Wave IV: 4.7 ms (mean)
(SD = + 0.5 ms)
Wave V: 5.5 ms (mean)
(SD = + 0.5 ms)
Inter-peak values at ~80 dB nHL presentation level
I - III IPL: 2.25 ms
(SD = + 0.5 ms)
III - V IPL: 2.0 ms
(SD = + 0.5 ms)
I - V IPL: 4.0 ms
(SD = + 0.5 ms)
abr transducer
insert
abr stim
click, chirp, tone bursta
abr rate
> 20/s
90/s useful for neurodiagnosis
abr intensity
variable in db nHL
10-90 dB
Relationship BW latency and Intensity
As intensity decreases the latency of the waves (wave V) increases
As intensity decreases the morphology of the ABR response deteriorates
abr & CHL
absolute latencies are pushed out but relative interwave latencies were retained within normal limits
abr & SNHL
wave 1 is prolonged (~ 2 ms)
wave 5 has normal latency (~ 6 ms)
Latency-intensity function shows a wave V not repeatable at 45 dB nHL – a higher hearing threshold
retro path & abr (vestib schwan
diminished wave I and absent wave III & V
What is congenital aural atresia? What is a condition associated with it? What is the FDA approved device for it and at what age?
failure of canalization results in this
associated with microtia & ME anomalies
spontaneous, can occur with Treacher collins, trisomy 22, crouzon’s & hemifacial microsomia
BAHA, after age 5 years old
man with bilateral mixed HL from 500-4000 in the high frequencies. What could be the cause?
Collapsing canals
What is the external canal condition caused by radiation to the head and neck?
ORN
OSTEORADIONECROSIS
what are the signs of impacted cerumen?
Mild CHL
tymps <.02 ml
Coughing
Dizziness
All the above
all
What is not the sign of it?
Otalgia
Tymps >.03 ml?
Complaints of fullness
Mild CHL
Dizziness
Tymps >.03 ml?
most common viral infection
accompanies VII N paralysis
earliest symptoms = painful rash in ear canal, concha, or below/behind auricle
rash caused by virus localizing in skin & results in painful vesicular (blister) eruptions
herpes zoster oticus (shingles)/ramsay hunt syndrome
outward scar tissue growth
follows ear trauma, piercings, viral infections (like herpes)
can spread
keloid
what is the most common cause of ear canal atresia
treacher collins
problem for younger children - cartilage is not fully developed
older adults - cartilage is deteriorating
collapsing canals
irregular & multiple
bony growth
most common
exostosis
less common
smooth and regular
osteomas
ALL PT PRESENTING WITH NON HEALING GRANULATION TISSUE IN EAC SHOULD GET BIOPSY
t
most serious complication that happens because of radiation that was used at the base of the skull bones due to cancer
can occur years after radiation
Osteoradionecrosis
List 2 surgical complications of otosclerosis & discuss one of them
OTSC surgery can result in a perilymphatic fistula and a decrease in WRS. Regarding PLF, if implanted prosthesis gets misplaced after surgery it can puncture a hole into the inner ear space allowing perilymph to escape into the ME cavity
Another complication is
Cholesteatomas are pseudotumors. Justify this. What are tymps findings of one that caused ossicular chain disarticulation? What is preferred treatment.
they are this because they are not considered tumors but they have same mannerisms like bone erosion, growth, and vasculature. They will take over and invade all structures that they contact, similarly to a tumor. In the R ear, tymps would show a type Ad with high static admittance. Surgery is the preferred treatment and antibiotics can be given beforehand to reduce inflammation and bleeding for surgery.
Define paraganglioma and give an example
paragangliomas arise from the paraganglia cells. it is a tumor along the jacobsons or arnolds nerves and an example is the glomus tympanicum. they can also arise from the bulb of the internal jugular and an example would be a glomus jugulare
What is inner ear homeostasis? What as an example of a condition/agent that can disrupt it
it is the balance of the ions and fluids in the inner ear and the maintenance of keeping it. An example is endolymphatic hydrops which is when there is an excess amount of endolymph as seen in Meniere’s disease.
What is TTS and PTS
both occur as a result of loud noise exposure. TTS happens when exposed to noise exposure and it can recover from 15 mins-14 hours and the threshold shift can return to baseline. PTS however doesn’t return to baseline due to irreversible damage to the cochlea. It usually doesn’t recover after 14 hours of noise exposure. HHL (need to look up to add)
What demographic group is most prone to otosclerosis
white women bw 20-40 yrs
What is correct for ossicular disarticulation?
only caused by temporal bone fractures
typically self correcting condition
hemotympanum is never reported with this
can be caused by a single exposure to very high intensity sound
ARTs are normal if tympanic membrane is intact
can be caused by a single exposure to very high intensity sound
Otosclerosis is a focal disease of
otic capsule
For NIHL, what is wrong
is caused by both dose and duration of disease
daily dose of noise exposure that doesn’t cause TTS usually doesn’t cause a PTS
consistent exposure to loud industrial noise can cause a NIHL but consistent exposure to loud music does not
noise notch in 3 and 6 kHz range is characteristic of NIHL
primarily NIHL will always progress to profound SNHL
consistent exposure to loud industrial noise can cause a NIHL but consistent exposure to loud music does not
primarily NIHL will always progress to profound SNHL
SSCD is differential diagnosis for otosclerosis. Clinically, they are differentiated by
purulent OM
tinnitus
normal ARTs
low static admittance (type C) or normal tymps
LF (rising) SNHL
normal arts
Jerger type Ad can be clinical finding in which disorders
ossicular disarticulation
cholesteatoa
Jerger type b HV can be clinical finding in which disorders
cholesteatoma
Glomus jugulare tumor can present with
unilateral CHL
unilateral mixed HL
tymp with jagged edges corresponding to PT pulse
intact but inflamed looking ™
all
all
FN weakness/paralysis potential complication for what conditions EXCEPT
glomus tympanicum
chronic suppurative OM
cholesteatoma
NIHL
gunshot wound to temporal bone
NIHL
which conditions are contraindications to surgery for OTSC
abg >/= 20 dB HL in affected ear
OTSC involvement of endolymphatic duct with meniere’s disease like s/s
SNHL in contralateral ear
SSCD in contralateral ear
none
OTSC involvement of endolymphatic duct with meniere’s disease like s/s
which infectious disease affect mother that results in congenital HL in fetus
CMV infection
rubella (german measles)
AIDS
All
a and b
all
17 yr old female has chronic bilateral OM since 6 mos old. Has had plenty of PE tubes but none for the last 3 years. Has significant allergies and frequency neg ME pressure (type c) bilaterally. Last ME infection was reported 3 yrs ago. She noticed hearing in right ear is worse for the last year. Copious foul smelling discharge noted on otoscopy in R ear. Pure tones show mild - moderate CHL in R and normal in L. Type b HV in R and type A tymp in left.
She most likely developed which condition due to chronic OM and/or negative ME pressure in R ear
what is the best treatment for this?
cholesteatoma
surgery
what is incorrect for glomus tumors
can arise from paraganglia cells on dome of internal jugular vein, arnold & jacobsons
glomus tympanicum can commonly grow to large size and cause hoarseness and dysphagia
several genes are associated with thee but most are sporadic
involvement of XII N indicates extensive growth of jugulare tumor
glomus tympanicum can commonly grow to large size and cause hoarseness and dysphagia