Answers:
If the following tympanogram was accompanied by an elevated EAC volume what would the likely diagnosis be?
A) Otosclerosis
B) Ossicular discontinuity
C) Middle ear effusion
D) TM perforation
E) Eustachian tube dysfunction
B) Ossicular discontinuity
C) Middle ear effusion
D) TM perforation
E) Eustachian tube dysfunction
This is a Type B tympanogram which indicates either a middle ear effusion or a TM perforation. The tympanogram is flat because there is a lack of compliance. If the middle ear has an effusion, then the TM is noncompliant due to resistant from the fluid, but EAC volume should be normal. However, in a perf the TM is noncompliant because pressure applied to the tympanogram is simply transferred into the middle ear and out the eustachian tube. EAC volume will be elevated because the volume of the middle ear is counted in this total due to communication via the perf. Eustachian tube dysfunction is indicated by a Type C tympanogram which has negative peak pressure. Otosclerosis and Ossicular discontinuity are indicated by Type As and Ad tympanograms respectively.
If acoustic reflex testing is performed and the pt only has an ipsilateral reflex of the left ear, what would be the most likely explanation for these findings?
A severe CHL in the right ear. No acoustic reflex is elicited when the CHL ear is stimulated as the signal is not intense enough to trigger it. Additionally, you may not always see a contralateral reflex if the normal hearing ear is stimulated if the middle ear pathology of the CHL ear involves the stapedius and prevents it from contracting. Thus, in severe CHL only the ipsilateral reflex of the normal hearing ear is present.
MC Questions:
Wave II in the following image corresponds to signal transduction through what structure?
B) Brainstem
C) Cochlear Nucleus
D) Peripheral CNVIII
E) Central CNVIII
Free Response Question:
What is the primary use of CHAMP?
Quick Facts:
Otoacoustic Emissions
-Objective, noninvasive, rapid measures of cochlear hair cell function.
-Byproduct of biomechanical motility
-Good probe fit and low ambient noise necessary.
-OAE detected in normal/near-normal hearing.
-Not detected if CHL/SNHL of 25-30 db or greater.
-Even middle ear pathology will eliminate OAE as stimulation intensity is decreased and signal cannot travel back to microphone.
-3 types = spontaneous, transient evoked and distortion
-Objective, noninvasive, rapid measures of cochlear hair cell function.
-Byproduct of biomechanical motility
-Good probe fit and low ambient noise necessary.
-OAE detected in normal/near-normal hearing.
-Not detected if CHL/SNHL of 25-30 db or greater.
-Even middle ear pathology will eliminate OAE as stimulation intensity is decreased and signal cannot travel back to microphone.
-3 types = spontaneous, transient evoked and distortion
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